Productivity Improvement Using VSM with Continuous Improvement and Addition of Auxiliary Devices into Conventional Machines: A Case StudyA DISSERTATIONSUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE AWARD OF THE DEGREEOFMASTER OF TECHNOLOGYINMANUFACTURING TECHNOLOGYSubmitted by:LAVNISH KUMAR SAROJROLL NO. 16205207UNDER THE GUIDANCE OFDr. RAJEEV TREHANANDDr. AJAY GUPTADEPARTMENT OF INDUSTRIAL & PRODUCTION ENGINEERINGDr.
B. R. AMBEDKAR NATIONAL INSTITUTE OF TECHNOLOGY, JALANDHAR – 144011 JULY – 2018DEPARTMENT OF INDUSTRIAL AND PRODUCTIONENGINEERINGDR. B R AMBEDKAR NATIONAL INSTITUTE OF TECHNOLOGYJALANDHAR, PUNJABCERTIFICATEThis is to certify that thesis titled “Productivity Improvement Using VSM with Continuous Improvement and Addition of Auxiliary Devices into Conventional Machines: A Case Study” being submitted by Lavnish Kumar Saroj to Department Of Industrial And Production Engineering, Dr. B R Ambedkar National Institute Of Technology, Jalandhar for the award of Master of Technology in Manufacturing Technology is a bona fide research work carried out by him under the supervision and guidance of the undersigned. His thesis has reached the standard of fulfilling the requirements of the regulations related to the degree. The contents of this thesis in full or in parts have not been submitted to any other university for the award of any degree or diploma.Dr.
Rajeev TrehanAssistance ProfessorDeptt. Of Industrial & Production Engg.Dr B R Ambedkar NIT Jalandhar Dr. Ajay GuptaAssociate ProfessorDeptt. Of Industrial & Production Engg.
Dr B R Ambedkar NIT JalandharCertified that M. Tech Viva-Voce examination of Lavnish Kumar Saroj (Roll no. 16205207) was held on…
. Successfully.Head, IPE Deptt. External Examiner Dissertation SupervisorsCANDIDATE’S DECLARATIONl hereby certify that the work which is being presented in the thesis titled “Productivity Improvement Using VSM with Continuous Improvement and Addition of Auxiliary Devices into Conventional Machines: A Case Study” in partial fulfilment of the requirement of the degree of Master of Technology submitted in the Department Of Industrial And Production Engineering, Dr. B R Ambedkar National Institute Of Technology, Jalandhar is an authentic record of my own work carried out during a period from July, 2017 to July, 2018 under the supervision of Dr.
Rajeev Trehan (Assistance Professor, Department of Industrial ; Production Engineering) and Dr. Ajay Gupta (Associate Professor, Department of Industrial ; Production Engineering)The report presented for the thesis has not been submitted by me for the award of any other degree of this or any other university.Date.
… LAVNISH KUMAR SAROJRoll No. – 16205207AcknowledgmentI would like to express my special thanks of gratitude to my supervisors (Dr.
Rajeev Trehan, Asst. prof. and Dr. Ajay Gupta, Asso.
Prof.) who gave me the golden opportunity to do this wonderful project on the topic (Productivity Improvement Using VSM with Continuous Improvement and Addition of Auxiliary Devices into Conventional Machines: A Case Study), which also helped me in doing a lot of Research and I came to know about so many new things I am really thankful to them.I want to thank Mr. Ramesh Kaliya and Mr.
Aman for allowing me in their company and trusted me for carrying out my work. I want to thank Mr. Aman, for showing me around a supporting me along the way. Special thanks go out to all the employees of Nivia Sport Pvt ltd, for being open and honest about their work and for answering all my questions. I wish all of you the best for the future. Thanks to my amazing friends group called as chicken buddy group including Praveen Kumar, Anurag Deepak, Deepak Kumar Singh, and Mahesh Nadiyala for giving their support. I will oblige to Mr.
Anurag Deepak, till my whole life, for providing me the greatest financial support. Thanks to my dear sister Ms. Rekha Regar for motivating and supporting me at all level. I want to pay special thanks to Radhe Shyam Sharma, Vivek Kumar, Mukesh Kumar, Vipul Kumar Gupta, Sudhanshu Tiwari ; Gaurav Yadav for assisting me.
I wish you well and hope we will meet again and again. I will oblige to my ex HOD, Dr. Vishal S. Sharma and Dr. Sarabjit Singh (Associate Professor) for being friendly with me in this institute.Finally, I want to thank my parents, grandfather, uncle and my elder sister Ms. Shalini Kumari for supporting me in many ways. Without their help and guidance, none of my experiences would have been possible.
Thanks to my girlfriend ‘Priya Singh’, for always being there, even at a distance.AbstractDue to a changing competitive environment, SMEs have to improve their production performance. A commonly applied philosophy to improve production performance is called lean thinking. This method, derived from the Toyota Production System, banishes wasteful activities while increasing the competitive strength and responsiveness of a company. Many companies fail in their attempt to become lean and therefore techniques are needed to guide the implementation. This thesis proposes to use Value Stream Mapping as an implementation technique for SMEs. This technique is tested in a company as a case study. By applying the Value Stream Mapping tool to a specific process (tennis ball manufacturing) within this company, substantial improvement potential is revealed.
Work content, process lead time and takt time can be decreased by 8.702%, 43.087% and 20.207% respectively.
Production and Productivity (in terms of production and worker) is increased by 25.351 and 31.049 respectively.
The thesis concludes that lean thinking is applicable to SMEs, at least under certain circumstances. Furthermore, Value Stream Mapping can be a valuable tool in revealing improvement potential.Table of Contents TOC o “1-3” h z u CERTIFICATE PAGEREF _Toc518773184 h iCANDIDATE’S DECLARATION PAGEREF _Toc518773185 h iiAcknowledgment PAGEREF _Toc518773186 h iiiAbstract PAGEREF _Toc518773187 h ivCHAPTER 1 PAGEREF _Toc518773188 h 1INTRODUCTION PAGEREF _Toc518773189 h 11.
1 Introduction PAGEREF _Toc518773190 h Error! Bookmark not defined.1.1.1 Productivity: – PAGEREF _Toc518773191 h 11.1.
2 Techniques to Improve Productivity PAGEREF _Toc518773192 h 21.2 Kaizen PAGEREF _Toc518773193 h 21.3 VALUE STREAM MAPPING PAGEREF _Toc518773194 h 31.3.
1 Waste and Value Streams PAGEREF _Toc518773195 h 31.3.2 Value Stream Mapping Process PAGEREF _Toc518773196 h 51.4 Line Balancing Method PAGEREF _Toc518773197 h 101.5 Thesis description and purpose PAGEREF _Toc518773198 h 111.6 Delimitation PAGEREF _Toc518773199 h 111.7 Goals PAGEREF _Toc518773200 h 11CHAPTER 2 PAGEREF _Toc518773201 h 12LITERATURE REVIEW PAGEREF _Toc518773202 h 122.
1 LEAN MANUFACTURING PAGEREF _Toc518773203 h 122.1.1 History PAGEREF _Toc518773204 h 122.1.2 5S PAGEREF _Toc518773205 h 172.1.3 Kaizen PAGEREF _Toc518773206 h 172.1.
4 Just-in-Time (JIT) PAGEREF _Toc518773207 h 182.1.5 Single Minute Exchange of Dies (SMED) PAGEREF _Toc518773208 h 182.
2 Effects of lean PAGEREF _Toc518773209 h 192.3 APPLICABILITY OF LEAN PAGEREF _Toc518773210 h 202.3.1 Country specific conditions PAGEREF _Toc518773211 h 212.3.2 Industry specific conditions PAGEREF _Toc518773212 h 212.3.3 Size specific conditions PAGEREF _Toc518773213 h 232.
4 LEAN IMPLEMENTATION PAGEREF _Toc518773214 h 242.4.1 Implementation method characteristics PAGEREF _Toc518773215 h 242.4.2 Show benefits beforehand PAGEREF _Toc518773216 h 252.4.3 Enhance cultural change PAGEREF _Toc518773217 h 262.4.
4 Implementation methods PAGEREF _Toc518773218 h 26CHAPTER 3 PAGEREF _Toc518773219 h 27METHODOLOGY PAGEREF _Toc518773220 h 283.1 RESEARCH STRATEGY PAGEREF _Toc518773221 h 283.2 Case selection PAGEREF _Toc518773222 h 293.2.1 Case company description PAGEREF _Toc518773223 h 303.3 DATA GATHERING PAGEREF _Toc518773224 h 323.
4 VALUE STREAM MAPPING APPLIED PAGEREF _Toc518773225 h 333.4.1 PRODUCT FAMILY PAGEREF _Toc518773226 h 343.4.2 CURRENT STATE PAGEREF _Toc518773227 h 343.
5 In-process Inventory with Process Cycle Time PAGEREF _Toc518773228 h Error! Bookmark not defined.3.6 Process steps PAGEREF _Toc518773229 h 363.6.1 Process data PAGEREF _Toc518773230 h 443.6.2 FUTURE STATE PAGEREF _Toc518773231 h 46CHAPTER 4 PAGEREF _Toc518773232 h 52RESULTS DISCUSSION AND SUGGESTION PAGEREF _Toc518773233 h 534.1 COMPANY DISCUSSION PAGEREF _Toc518773234 h 564.
2 GENERAL DISCUSSION PAGEREF _Toc518773235 h 574.3 Suggestions. PAGEREF _Toc518773236 h 584.3.
1 Using of Auxiliary Devices PAGEREF _Toc518773237 h 584.3.2 Process rebalancing PAGEREF _Toc518773238 h 654.4 IMPLEMENTATION PAGEREF _Toc518773239 h 14.4.1 Dependable suppliers PAGEREF _Toc518773240 h 14.
4.2 Reduce the eighth waste PAGEREF _Toc518773241 h 24.4.
3 Workplace improvement PAGEREF _Toc518773242 h 34.4.4 Paced production (pilot) PAGEREF _Toc518773243 h 34.4.5 Machine redesign PAGEREF _Toc518773244 h 4CHAPTER 5 PAGEREF _Toc518773245 h 5CONCLUSION AND IMPLICATIONS PAGEREF _Toc518773246 h 55.1 RESEARCH QUESTION PAGEREF _Toc518773247 h 55.2 GENERALIZABILITY PAGEREF _Toc518773248 h 75.
3 ACADEMIC RELEVANCE PAGEREF _Toc518773249 h 75.4 MANAGERIAL IMPLICATIONS PAGEREF _Toc518773250 h 75.5 LIMITATIONS AND FUTURE RESEARCH PAGEREF _Toc518773251 h 75.5.
1 LIMITATIONS PAGEREF _Toc518773252 h 85.5.2 FUTURE RESEARCH PAGEREF _Toc518773253 h 8List of Figures TOC h z c “Figure” Figure 21 Demand and Supply PAGEREF _Toc518742389 h 22Figure 31 Value Stream Mapping Graph PAGEREF _Toc518742390 h 36Figure 41 Block diagram of Open loop control system PAGEREF _Toc518742391 h 59Figure 42 Block diagram of Open loop control system PAGEREF _Toc518742392 h 60Figure 43 PID Controller PAGEREF _Toc518742393 h 61Figure 44 Temperature Controlling Device PAGEREF _Toc518742394 h 63Figure 45 Pressure Controller Devices PAGEREF _Toc518742395 h 63List of Tables TOC h z c “Table” Table 41 PAGEREF _Toc518742359 h 53INTRODUCTIONRequirement of things and products depend on quality of service, availability and numbers of customers. At current, there are many numbers of companies to produce products and materials. Due to growth in population, demands of finish products are increasing and resources are shorting day by day. So that to compete to growing industries, there is a need of to improve productivity by eliminating the wastes using value stream mapping (VSM) lean tool which emphasize different types of wastes in running process.
By observing the wastes we need to reduce the wastes form the manufacturing process. 1.1Productivity: – It means that what to be obtained against what to be invested. Generally, it is a ratio of output to input. Here output refers to services or finish products or combination of both. And input refers to 5M i.e. manpower, machines, materials, money, and methods.
Sometime productivity refers in terms of total revenue generated to the total investment in the form of money. Mathematically it may be written asProductitvity=OutputInputProductivity can be increases by different things such as1.1.1 Increasing in output at constant inputProductivity may be increase as increasing the production rate with constant input. This type of increment takes place by changing the method of operation or by changing the work environment. Good relationship between supervisors and workers, creates motivation among them and due to motivation, workers work properly and enhance the production rate with constant investment of money, that’s why productivity would be increased.1.
1.2 Constant output with decreasing inputThis type of productivity increment occurs due to changing the working methods, upgrading the system form manual to the automation for example assume that we make a pool whose selling price is 2500000. If we make to dig that pool with manpower, then it becomes costly as compare to if we make to dig that pool with JCB (a bulldozer machine). It means in case of bulldozer machine input cost is less as compare to in case of manpower that’s why it will be decrease the investment with constant output. And such that productivity will be increased.1.1.3 Increasing in output with less amount of increasing in inputSuch type of productivity increases with changing the conventional methods to advance methods, improving the machine quality with addition of some auxiliary devices which are able to reduce the cycle time.
For example, if we cook mutton in handy it takes more time that’s why it needs more heat and due to which energy cost increases, but the cost of that pot is very less. If we use the pressure cooker in place of handy whose purchasing cost is very high as compare to handy but it takes lesser time than handy and that time period, it cooks more mutton than handy. That’s why it increases the output with less amount of increasing in investment.1.1.4 Eliminating of wastes.Productivity of a plant may be increased by eliminating the different types of waste which are classified as reducing the needless motion, lead time, over-processing, over-production, WIP, transportation, and defects. By removing of these type of wastes productivity would be increased.
Techniques to Improve Productivity or ProductionThere are many techniques to improve the productivity of a plant, organization, company or a service provider industry. But I have done a project which is based on production increment of tennis ball manufacturing plant using kaizen method, and also addition of some auxiliary devices which is used to reduce the cycle time of machine that’s why value added (VA) time would be reduced and also non-value added (NVA) time would be reduced. Reducing of VA and NVA time, lead time also reduced. Due to reduction in cycle time, production would be increased with less amount of investment i.e.
adding of auxiliary devices and that’s why productivity will be increased. Now I will discuss about different type of productivity improvements techniques which are given as follows.KaizenThis word is taken from japan which states that “change for better” with implicit meaning of either “philosophy” or “continuous” in Japanese dictionaries and in everyday use. Many times it is known as continuous improvement is a long-term perspective to work that systematically explores to achieve small, incremental changes in processes in order to improve efficiency and quality. Kaizen is more than just modus operandi for continuous reformation.
It is not a distinct tool or set of tools to enhance quality. Kaizen is a journey and not a target. The objective of Kaizen is to renovate productivity, detract wastes, eliminate unnecessary hard works and humanize the workplace.
It is effective at identifying the three basic types of wastes i.e. Muda, Mura and Muri. Kaizen philosophy enables everyone to suppose responsibility for their processes and improve them. With Kaizen, workers, machine operators, supervisor or all employees at all levels of the organization are engaged in constantly watching for and identifying opportunities for change and improvement. Kaizen or continuous improvement is not just a one-time event; more precisely, it is a process that occurs every day.VALUE STREAM MAPPING This section will describe Value Stream Mapping in more detail. Value Stream Mapping, known at Toyota as “Material and Information Flow Mapping”, is a method which helps practitioners to identify systemic sources of waste in a process and subsequently how to eliminate these source on a structural basis.
A key characteristic of the method is that it looks at a process as a whole, rather than at the level of sub-processes. The method allows for process wide improvement, rather than local optimizations which often negatively affect other areas on the process.Emiliani et al. show the wide applicability of VSM by using VSM for determining the beliefs, behaviors and competencies possessed by business leaders. Wastes and Value StreamsVSM revolves around two main concepts, “Waste” and “Value Streams”. According to Sugimori, “Waste is anything other than the minimum amount of equipment, materials, parts, and workers (working time) which are absolutely essential to production are merely surplus that only raises the cost”. According to TPS, there are the following seven wastes with possible examples of each waste: Waiting: Processes are ineffective and time is wasted when one process waits to begin while another finishes. Instead, the flow of operations should be smooth and continuous.
According to some estimates, as much as 99 percent of a product’s time in manufacturing, is actually spent in waiting. A processed part is waiting in a box to be moved to the next step in the process, because not all the parts from the batch of this part have been processed at this step. Transport: Moving a product between manufacturing processes adds no value, is expensive and can cause damage or product deterioration. A part is processed in one step, transported to the warehouse, put away and transported back to the production floor when the part is processed at the next step. Inappropriate processing: Overly elaborate and expensive equipment is wasteful if simpler machinery would work as well.
For example; cutting a part with a tolerance of 0.1 mm, while the customer only demands a precision of 0.5 mm. here it shows over processing which is inappropriate processing.
Overproduction: Manufacture of products in advance or in excess of demand wastes money, time and space. Producing more than demanded by the customer. This leads to excess inventory and possibly to obsolescence of products. Unnecessary inventory: Holding months of inventory of parts which are rarely used and available from a supplier on a short term basis without a cost premium.
It wastes resources through costs of storage and maintenance.Motion: unnecessary motion takes place to carry products or goods when tools or parts which are located far away from the place where they are used in the process. Resources are wasted when workers have to bend, reach or walk distances to do their jobs. Workplace ergonomics assessment should be conducted to design a more efficient environment. Defects: A mistake made in the beginning of the process is not detected until the product reaches a quality inspection at the end of the process. Mastroianni et al.
added an eighth waste to this list: “Not utilizing human resources”. This is the common phenomenon that ideas for improvement from (production) employees are not gathered or not implemented. Monden, et al. told that as wasteful activities are Non-Value-Added (NVA) activities, there are also Value-Added activities (VA). These are the activities the customer is willing to pay and wait for. Finally, there are activities which are wasteful, but currently necessary to the process.
This type of activities is classified as Necessary-Non-Value-Added activities (NNVA). An example of an NNVA activity is when parts are transported to a different production hall, because in that area toxics are used and special safety measures have to be in place to ensure the well-being of the employees. The transportation is wasteful, but essential to the production of the product. Rother et al. differentiated between VA, NVA, and NNVA activities leads to the second concept of VSM; the Value Stream. A Value Stream is “all the actions (both value added and nonvalue added) currently required to bring a product through the main flows essential to every product” Purely speaking this is the combination of all the steps from the production of raw materials to the delivery of the product to the final customer. To delimit the scope of the Value Stream, practitioners generally focus on the “door-to-door” production process inside a plant. This is practically more attainable and allows to focus on the process you can influence, namely the process inside your own factory.
Value Stream Mapping Process The Value Stream Mapping process consists of different steps. First, one product family, based on similar processing steps and required equipment, is chosen to be the focus of the improvement effort. This reduces the complexity of the studied process. The product family should be described and delimited clearly to avoid confusion in the following steps. 1.3.2.
1 Current State After choosing the product family the current state of the value stream is described in the typical VSM fashion. First, the information about customer demand is gathered. Essential information is the amount of products produced and the time frame in which this takes place, because this leads to the so-called “takt time”. Takt Time It is the average rate at which a product is demanded, spread over a certain production period. For example, if the average daily demand for product X is 450 pieces and the daily production time is 7.5 hours, or 450 minutes, the takt time is 1 minute.
To fulfil demand, the process should be able to deliver a product every minute on average. It should be noted that the length of the takt time is unrelated to the amount of work content which is needed to produce one item. All gathered data is represented in one overview, to visualize the entire process and all its relevant aspects. Then, all process steps the product family passes are defined.
Examples of process steps are master batch mixing, half core curing, cutting, grinding, full core curing, cloth wrapping etc. Per process step, some process characteristics are measured. Generally, these characteristics are data such as: Cycle time The average elapsed time from the moment one good piece is completed until the moment the next good piece is completed. Cycle time is measured at the last process step in the value stream, and it shows how often one acceptable unit of product can be completed and provided to the customer. Within the value stream, cycle time is used to show how often one unit of “good” work-in process is completed and moved to the next process step in the value stream. Cycle time is perhaps the single most important piece of data that is captured in Value Stream Mapping.
From this single piece of information associated with process steps throughout the value stream, you can see how the production process flows at the most basic of levels. Obviously, there are other things that happen throughout the value stream that affect this flow. But with just this one piece of information shown and compared to the Takt time, it is possible to see if there is an opportunity to meet customer demand.
It is represented by C/T.Change over time Changeover time is the elapsed time from the moment the last good piece of one product run is completed to the moment that the first good piece of a different product is completed. In other words it is the time to switch from the production of one type of product to the next. There are many instances where a changeover should be reported, but none are “scheduled” during the allotted mapping exercise time. The tendency of many mapping teams is to hold a mapping session with operators in the value stream and estimate this change over time.
This may be the least accurate piece of information that you can estimate from this type of session. Many operators historically greatly under- or overestimate changeover time, depending on the situation explained. Many operators will underestimate because they think that the time is just what it takes to change out the tooling. It is denoted by C/O.Available working timeIt is the working time allotted to the plant operation which is calculated as working time per day or per shift. The net available time is the time that the doors are open and the value stream is operating. Start with the total time that the doors are open and the lights are on.
Subtract out any time that the value stream is not operating due to meetings, breaks, lunch, or other scheduled downtime. If the process continues to operate during breaks, lunch, or other scheduled downtime, do not subtract this time. Idle time or any other time that the process is not operating, but is waiting on something, anything should also remain in the net available time. Just because we are not running the value stream does not mean that we do not count the time. We are looking at “time available” to run the value stream, not actual run time. Work contentWork content is the total amount of actual value-added and non-value-added labor time associated with a process.
Work content adds together the labour time used by each employee working within the process step. It is represented as W/C.Amount of workers Amount of workers are the number of worker who are needed for a particular operation or process simultaneously working at that process step. In other word the total number of workers which are needed for a particular operation.Defect ratesA defect is a unit of work that is scrapped or reworked within any step of the value stream. And defect rate is the ratio of total defective pieces to the total number of pieces produced.
Uptime Uptime is the percentage of time that a piece of equipment works properly when the operator uses it for the prescribed task. Asking someone how often a piece of equipment works or doesn’t work when he or she walks up to use it can be a confusing question for many people. Typically, operators want to discuss the percentage of the total time (i.e.
, the total time that the doors are open and the lights are on), rather than the percentage of time that equipment does or does not workInventory levels (work in process; WIP)It is the quantity of materials which are available between two consecutive processes.Note- Information is also gathered about the delivery frequency to customers and from suppliers. To fully understand the process and to improve data quality it is advisable to collect these data first hand. Material movements between processes are visualized with different types of arrows, depending on the type of material management and handling between the two steps. After describing the process steps, inventory levels between each step and at the beginning and end of the entire process are measured. Generally, the inventory levels are expressed in volume and inventory time in days, hours or minutes. For example, there are 3600 pieces waiting in front of process step Y which takes half a minute per product and is demanded at an equal rate. With a working day of 450 minutes, it will then take 4 days to process the stock in front of process step Y.
For reasons of simplicity down time and setup time are generally not taken into account. Practitioners argue that inventory levels only need to be measured once to give a general indication of how much time products spend waiting. They reason that even though inventory levels at each separate step can vary, normally the total level of inventory is more or less constant. Also, waiting time often represents such a significant fraction of the time it takes a product to flow through the entire process that even if this fraction varies it still shows that products spend too much time waiting.
Time LineAt the bottom of the process visualization a timeline is drawn. This timeline shows the total time a product takes to flow through the process, differentiating between value added time and non-value added time. This timeline can give striking insights, for example: “It takes us four weeks to perform ten minutes of value added time.” The percentage of value added time respective to the total time can strengthen this argument. Finally, all information flows are depicted.
Essential information flows are the incoming order process, the procurement procedure and the production planning within the focus process. This visualizes possible inefficiencies in how necessary information flows between different departments and other stakeholders. Now, the entire process and the relevant information and material flows are visualized in one picture. Also, there is some indication of the state of the process.
The following step is to devise the future state of the process. 126.96.36.199 Future State To come up with a future process which is lean and where root causes of waste are eliminated as much as possible.Rother et al. presented seven guidelines for lean value streams and eight guiding questions to analyse the parameters of the process.
The seven guidelines are as follows: Produce to your takt time: produce at the rate, customers demand your products. Continuous flow: where possible, let products flow one piece at a time, instead of in batches. Supermarkets if continuous flow is not possible: A ‘supermarket’ is a lean method to link a process step to an upstream step which still needs to be run in batches. When enough items have been taken from this supermarket, a signal is sent upstream to start production of one batch. In this way, total work in progress is limited and production is closely linked to actual customer demand.
Schedule production at one step only: as all the process steps are closely linked, either through supermarkets or through continuous flows, it is only needed to schedule production at one specific step. This is called the ‘pacemaker processes. Level the production mix: If multiple types of products are produced in the same flow, it is essential to mix the production of the types as much as possible. For example, if products A and B are produced in one line, it can be tempting to produce a batch of product A during one week and a batch of product B in the next to decrease the number of change overs. However, this leads to higher levels of work in progress and final product inventories. Furthermore, it creates an unlevelled demand for items which are used as input for the process. This, in turn, creates a ‘bullwhip effect’ of increasing fluctuation in demand throughout the entire supply chain.
Level production volume: release fixed amounts of work onto the production department. This allows the department to understand frequently if they are on schedule with their work and whether they should intervene. Shorten change over time: focusing on shortening change over time allows to decrease batch size and thereby improves stability and enables a levelled production. Linked to the seven guidelines there are eight questions which offer guidance to develop the future state of the process: What is the takt time? Will you build to a finished goods supermarket or directly to shipping? Where can you use continuous flow processing? Where will you need to use supermarket pull systems? At what point will you schedule production? What is the pacemaker process? How will you level the production mix at the pacemaker process? What increment of work will you release to the pacemaker process? What improvements are necessary to enable the implementation of the future state? By answering these questions, the future state becomes apparent. This future state is visualized in similar fashion as the current state.
The percentage Value Added Time should have increased significantly. Finally, necessary improvements to reach this future state are depicted in the same overview. The last element of the Value Stream Map analysis is planning the implementation towards the desired future state.
To do so, the future state process is split in different segments, or loops. Then, the order in which the segments are implemented is defined and per segment a plan is made, including steps to take, responsibilities and goals. There is no recipe for a lean implementation, but there are some guidelines about with what segment to start. It is advisable to start with a part of the process which is well-understood by the people involved in that area and where the odds of success are favourable. Furthermore, it is preferred to start in a field with large potential gains. It should be noted however, that this last criterion can be conflicting with the first two and this should be carefully dealt with. Line Balancing MethodAccording to this method firstly we calculate the line efficiency of production line which states that how much profit generated against invested cost.
It may be reduced by reducing of number of workstations. The number of workstations are reduced by eliminating not necessary process or by combining of sub workstations in to a main workstation. Typically,This method is used to reduce the idle time. Due to decrement in the idle time of the production line, the lead time of production line also decrease and also it decreases the cycle time indirectly. By these things of time reduction, the number of cycles produced in a day may be increase and that’s why productivity may be increased.Thesis description and purposeThe thesis will analyze the current situation at the tennis ball manufacturing section (TBMS), at Nivia Sports, to find production losses.
When the losses are found, they will be analyzed to find the underlining problems. The purpose of this project will therefore be to find solutions for the problems, to ensure that a high productivity is reached at a low cost, and that the lines capacity covers the demand of their products.DelimitationThe thesis work will be done during a 20-week period, at Nivia Sports Private Limited, Jalandhar. The analysis will be done on the tennis ball manufacturing (TBM) line and therefore it includes many workstations with visual inspection & finishing (VIF) station.
The description of the current situation is based on data gathered from August 2017 to March 2018 and therefore any changes in the production system past that time will not be considered, for future reference this period will be called the data gathering period. GoalsThe goal is to present a solution to increase the productivity of the TBM line at Nivia Sports. To reach this goal some sub goals has been constructed to help in the thesis.
These are: An analysis of the different work tasks and how the operators spend their days. An analysis of the machine data.An analysis of the changeover procedure.LITERATURE REVIEWIn this literature review first the history of lean manufacturing, its most commonly used tools, and the results which can be achieved by implementing lean will be elaborated upon.
Then, the applicability of lean manufacturing in different fields and types of companies will be discussed. Finally, the methods of implementing lean manufacturing are covered which results in the hypotheses of this research. LEAN MANUFACTURING This section will give an overview of the history of Lean and the Toyota Production System (TPS), its most prominent tools and finally the results which can be achieved through implementing lean thinking. History After the Second World War Japan suffered from high costs of raw materials due to a lack of resources. This made Japanese companies less competitive on the global market. Sugimori et al. discussed about Toyota production system that which recognized that in order to compete, company needed to “produce better quality goods having higher added value and at an even lower production cost than those of the other countries” (Normally, this would call for the implementation of mass production techniques, which dominated the industry at the time.
To decrease cost, Toyota put a severe focus on the elimination of waste, which is “anything other than the minimum amount of equipment, materials, parts, and workers (working time) which are absolutely essential to production are merely surplus that only raises the cost”It might sound trivial that the ‘secret’ of Toyota is eliminating all the process steps which do not add value, but studying the Toyota Production System more closely reveals some insights about how fundamentally different it is from traditional manufacturing views. All workers in Toyota factories are allowed to stop the line they are working on if they find a defect, by pulling a cord next to their working station. Also, every employee at Toyota has the right, and is encouraged, to make improvements to the production processHolweg et al. states that Eiji Toyoda, head of the Toyota Company at the time, was indeed determined to become a mass producer. This would require acquiring expensive production means which were specialized at producing large batch sizes of products. These large batches were necessary to spread the large investment over enough products, and to deal with lengthy setup times. However, the relatively small home market of Japan, combined with capital constraints, initially prevented Toyota from setting up such a mass production facility. They discover that the batch and queue method makes the producer incapable of delivering the product diversity demanded by consumers indirectly.
Also Toyota recognized what they had to do: make low cost, low waste, high value products by combining different production techniques into a system which would produce a wide mix of products with low volume per product variety. An important person in the quest of Toyota to reach this was Taiichi Ohno, who joined Toyoda Spinning and Weaving in 1932. High quality should be attained by decreasing batch size, since Ohno had recognized that large batches, amongst having other effects, resulted in high number of defects.Some believe that Toyota ‘invented’ a new production method, but actually it took some decades to become the Toyota Production System (TPS) as it became known to the rest of the world.TPS was first not understood by Western companies and academics and the superiority of TPS was sometimes bluntly negated. Then Holweg gives a clear insight in the development of understanding Toyota’s production methods and this will be elaborated upon next. Karmarkar et al.
discussed that Toyoda also recognized some major, structural flaws in the mass production methodology Apart from financial and economic restrictions. To be competitive, mass producers aim to benefit from economies of scale. To reduce unit setup and machine costs, they generally produce in large batches of identical products which work their way through the production facility.
As a result, “parts spend most of their time waiting in queues rather than in being actually processed”. In concurrence with Little’s Law, this results in longer lead times. This ‘batch and queue’ method is problematic for a number of reasons. By elongating the time period between fabrication of a part and its use in a following process step increases the risk of loss or deterioration while it also increases the time between fabrication and possible feedback about quality. Furthermore, the level of safety stocks grows more than proportionally with lead times, since the safety stocks have to protect against longer lead times as well as greater variability in forecasts due to a longer prediction horizon. Finally, long lead times decrease a company’s competitiveness due to distant due dates and make companies less responsive to customer demand.
Fujimoto discussed that over a span of several decades, starting in the 1950s, Toyota slowly developed its production system. The production managers at Toyota (such as Kiichiro Toyoda, Taiichi Ohno, and Eiji Toyoda) combined elements of a mass production system with their own ideas. Spear studied that it is different from traditional plants, where special teams implement improvements and where extensive quality controls check for defects at the end of the line. All employees at Toyota learn to make improvements according to the so called Scientific Method. When employees detect a problem, they try to find out the root cause and a countermeasure of that problem which copes with this cause.
They make a hypothesis about the effect of the countermeasure before they implement the countermeasure. Finally, they compare the actual to the predicted effect and investigate the possible difference. As such, they aim to truly understand not only the problem, but also the solution. The hypothesis based improvement process makes it ‘scientific’. Abernathy et al.
studied about TPS and they found that the first barrier to understand TPS was that it was not documented before 1965, when it was communicated, in Japanese, to Toyota’s supplier network. At this point, Toyota had already started a steady increase in market share. During the 1970s concerns amongst Western producers about Japanese imports rose. In 1980, 22.2 percent of personal cars sold in the United States came from Japan.
Trade agreements were instituted to restrict the number of imported cars. Toyota worked around these restrictions by setting up assembly plants in the United States. They understood that the competitive advantage was mostly explained by superior manufacturing practices. In 1985 the International Motor Vehicle Program (IMVP) started to investigate why Japanese companies were outplaying Western companies and how large the gap was. The IMVP was a research program focused on the automobile industry, consisting of researchers from all over the world, based at the Massachusetts Institute of Technology.
Krafcik et al. discussed that a major breakthrough in accepting the superiority of TPS was instigated by a collaboration between Toyota and General Motors (GM), called the New United Motor Manufacturing (NUMMI) joint venture. In this joint venture, initiated in 1984, Toyota and GM reopened a former GM plant to produce cars of both brands. After the first year, the productivity at the NUMMI plant was more than 50 percent higher than the productivity level at another GM plant which was technologically similar. Also, the NUMMI plant had the highest quality standards of all GM’s U.S.
plants. Under Toyota’s leadership, labour input per vehicle was reduced to 19 hours, down from 36 hours previously. Defects dropped from 1.5 to 0.5 per 100 vehicles, and absenteeism decreased from 15 percent to 1.
5 percent. NUMMI achieved these results without great changes in used technology and by hiring mostly the same 12 workforces of when the plant closed in 1982. This convinced the industrial sponsors involved in IMVP, of the fact that Toyota’s true advantage did not lay in factors such as culture, but in its production philosophy. One of the academics working for IMVP, was the first to use the term ‘lean production’. ‘Lean production’ is a more generic term for the principles instituted in TPS.Liker et al. states that lean is “a philosophy that when implemented reduces the time from customer order to delivery by eliminating sources of waste in the production flow”.
Elliot et al. states that the three basic principles of the lean philosophy are flow, harmony (pace set by customer demand), and synchronization (pull flow). He argues that these three principles should be present throughout the entire organization.Fawaz A. et al. demonstrate that a detailed simulation model can be used to evaluate basic performance measures and analyze system configurations. The availability of the information provided by the simulation can facilitate and validate the decision to implement lean manufacturing and can also motivate the organization during the actual implementation in order to obtain the desired results.R.
Radharamanan et al. discussed that it is important to point out that Kaizen methodology does not require large capital investments in comparison with the innovation (as in the case of reengineering), and the results can be improved significantly in some cases. Thus, the enterprises involved can guarantee better positions in the competitive market, generating profits and minimizing costs.Turfa emphasizes that lean manufacturing is not a tactic, but should be viewed as an endless journey a company embarks on.Blas Mola et al. discussed that Willow for bioenergy is a fairly new cropping system, with lower levels of related experience and development than most other agricultural crops.
The model developed in this study shows that the production of willow plantations in Sweden has increased during the last years at a good rate, starting with very poor results from plantations established in the mid-1980s but achieving significantly higher production levels in more recently established plantations. From this model, we can better understand the high variability of yields from plantations, resulting from changes in farmer attitudes and practices. Management, together with genetic improvements, are determining factors in the success of commercial plantations; it is expected that more experience among farmers, better advisory service, and improvements in varieties will result in a significant increase in mean yields during the next years. In this respect, the importance of breeding programmes together with training for growers is stressed, as well as mechanisms to encourage best practices in order to reduce the gap between actual and potential yield in commercial willow plantations. Despite its limitations, this study is the first known to the author that analyzes the increase of productivity in commercial willow plantations based on extensive empirical data, and it is a starting point for further research on the topic and for informing economic and policy decisions.Ohno remarks that apart from the critical focus on eliminating waste, respect for humanity was equally important.Hall states that Lean and TPS are similar, but not the same. According to him the key differences between lean and TPS are in the focus at the start of the process, the source of the solutions and the level of standardization.
TPS usually starts with optimizing each separate process to achieve zero defects and therefore takes a detailed perspective in the beginning, before optimally linking the steps together. Lean starts with a broader view, looking at the entire process and identifying main sources of waste, which often occur at the boundaries of processes. Lean generally focuses on the implementation of tools, coming from a predetermined set of tools, to eliminate waste. These implementations are more likely to be driven by staff, which prevents employees to increase their problem solving skills. TPS focuses strongly on employee skills and allows countermeasures to problems to evolve more organically. Finally, it seems that TPS emphasizes more strictly on the standardization and documentation of work methods. This allows them to continuously ‘test’ if the work methods are adequate or can be improved.
Naga Vamsi Krishna Jasti et al. studied that Indian automobile industry is one of the fast developing industries with growth rate of 14-18 percent per year. However, the major automobile organizations are facing problems to fulfil the customer requirements and to stay competition with the global Lean Tools players in terms of cost, quality and services. Some of the notable automobile industries are able to meet the customer requirements in the aspect of delivery time and demand. One of the reasons why most of the Indian manufacturing organizations or auto-component industries are still not able to implement advanced manufacturing systems (like LM) is due to lack of knowledge and information. Hence most of the auto-component industries are spending much of their resources to fulfil the customer requirements. The objective of the research is to check the application of VSM in Indian auto component industry.
The study clearly shows that VSM is important LM tool, which can be used to identify various wastes in the production system of Indian manufacturing industries. The study results clearly proved that all types of lean wastes can be identified with the help of VSM. Currently, it is in improvement phase and giving commitment for its uninterrupted efforts in elevating technological frame and quality improvement. The results obtained from the study may help other companies to find methodology to implement the LM tools like VSM.
5S This method aims to improve work area efficiency by strictly selecting what material is essential at certain workstations. This material is given a specific location close to where it is required. Non-essential materials are placed on less prominent locations. In the translated version, the five ‘S’s stand for Sort, Straighten, Shine, Standardize, and Sustain. The 5S methodology is aptly summarized by the following statement: Mastroianni et al. states that 5S stands for “A place for everything and everything in its place” Kaizen Kaizen is the Japanese expression for “improve for the better”.
It is the daily effort to constantly improve the process of a company. Origins of wasteful activities are identified and sought to be eliminated. Womack et al. discussed about kaizen according to them on top of the daily effort, special Kaizen events, called Kaikaku events can lead to more breakthrough improvements. In such events, a specific process is studied in great detail to achieve more substantial improvement.
Just-in-Time (JIT) By producing products and parts ‘just in time’ it is ensured that only the necessary amounts of products and parts are produced. Furthermore, parts arrive to the process where they are needed at the right time and are placed in the order in which they are needed. This decreases the amount of waste associated with excess inventories. Single Minute Exchange of Dies (SMED) In order to be able to produce in unitary batches with the flexibility demanded by the customers, it is essential to have extremely short change-over time. Holweg, et al. describe about SMED in 2007 which states that a great advancement in change-over reduction was achieved by Shigeo Shingo, who was hired as a consultant at Toyota. His method studies the process of a change-over with great detail and identifies wasteful activities and activities which can be performed while the machine is running.
Eliminating or relocating these activities can reduce change-over times from hours to minutes. Klefsjö et al. describe that one of the tools often mentioned in combination with lean is Six Sigma, a method developed at Motorola and made famous by the implementation at General Electric.
It is a method to identify and eliminate variability in a process and has the goal to improve quality. Kumar et al. studied that this method is especially useful when the source of defects and variability is not apparent).
Due to the strong statistical analyses required, Six Sigma projects are led by specially trained professionals. Smith et al. emphasize a research which shows that the most effective way to improve processes is to implement a combination of lean and Six Sigma tools, often termed Lean Sigma. Most companies combining lean and Six Sigma start by improving their process with lean tools. This eliminates a large fraction of errors and waste, but chronic problems might still exist. These chronic problems are then attacked by Six Sigma tools.
As implementing Lean Sigma starts with the implementation of lean, also for this combination it is relevant to understand how to start with lean. Spear et al. described that it should be emphasized that lean is more than just the tools, and should be seen more as a philosophy. For Toyota, none of its tools are key to its production system. It sees the implemented tools as countermeasures to problems not yet solved. Tools are not viewed as solutions, because that would imply a permanent fix. For instance, counter to popular belief, Toyota does have inventories of parts and subassemblies. These inventories are countermeasures to the problem that transportation time from supplier to assembly line is still higher than zero seconds and that no supplier can guarantee infinite quality and reliability. Many companies trying to imitate Toyota’s production system have focused on the tools, instead of on the principles. This may lead to a production system which is rigid and inflexible and, possibly more important, does not evolve and improve to cope with changing external factor. Effects of lean Soriano et al. states that the real benefit of lean stems from strengthening the entire system. Lean methods ensure that shortcomings of the systems reveal themselves quickly by the profound influence they have. This should trigger a quick response of the company to eliminate the shortcomings. The effect of this approach already became apparent in the early research on Toyota’s production performance Lathin et al. claimed that traditional mass producers should be able to reduce their lead time by 90 percent and inventory levels by 90 percent, and increase labour productivity by 50 percent. Ahlstrom has done a case study research showed substantial improvement potential as a result of lean practices as well. He reports a case where 85 percent reduction in the number of defects, 94 percent reduction of manufacturing lead time, and 50 percent reduction in sales lead time are achieved. Abdulmalek et al. described a case study based on industrial experiments. On the basis of that results and finding they report a potential of reducing production lead time with 70 percent of and work-in-progress levels by 90 percent. These statistics are taken from a variety of companies with little information of the initial state of the companies. Therefore, they have little predictive value of the improvement potential for any given organization contemplating a lean initiative. Then again, achieving a fraction of these substantial improvements could already be attractive for many companies. Allen et al. have expressed scepticism about the lean approach. Critics claim that success statistics of lean are overstated either due to neglecting unsuccessful lean efforts or by overly attributing improvements to partial conversion to lean. Landsbergis et al. studied other critique on the lean approach which concerns employee wellbeing. Some research reports that production employees encounter intensified work pace without gaining autonomy. Others even accuse companies such as Toyota of dangerous conditions for workers and accident cover-ups. These reports are contradicted by other research, which claim that even though work pace is high in lean environments, conditions are within an acceptable range. Conti et al. describe that the opposing findings limit a conclusive answer to the question if the lean approach has a positive or negative effect on employees. An extensive survey showed that the effect on employees is determined mostly by management behaviour, not by an intrinsic effect of the lean approach. In summary, by implementing lean thinking in an organization substantial results can be attained in terms of lead time reduction, efficiency increase and quality improvements. If managed correctly, this approach can also have a positive effect on the workforce. APPLICABILITY OF LEAN Lean terminology is used in many areas to overcome the production that to be demanded. It is mainly used to reduce the waste and produce only demanded quantity. It is applicable in all types industry like manufacturing and service providing industry.Womack et al. expressed that the applicability of the lean philosophy in other countries, industries, and company sizes was questioned from the moment it revealed itself to the world outside Toyota. This section will investigate the applicability of lean to different conditions. Country specific conditions When confronted with early studies about Toyota’s production performance, various Western researchers and automotive industry representatives negated the intrinsic advantage of Toyota’s system. Given explanations, some even in official hearing, revolved around country specific advantages, such as favourable exchange rates, cultural differences, and government policies. Abernathy et al. studied that Toyota itself believed that their production system was particularly ample in dealing with external issues specific to the Japanese economy and in capitalizing on traits specific to Japanese workers. Furthermore, Toyota indeed had the benefit of, for instance, a supportive government. Possibly, the proposed explanations where relevant enough to use them as a protection from accepting another’s superior thinking. Voss et al. showed that lean thinking also offers benefits for non-Japanese companies located outside Japan. They claim that lean thinking has now become implemented across Western industries. Industry specific conditions The lean philosophy was developed in an environment strongly focused on manufacturing. As it is often termed “lean manufacturing” or “lean production” it seems to keep the connotation of being applicable only to production environments. However, vast amounts of research have shown the benefits attainable by applying lean to service environments. Examples are call centres, healthcare institutions, car repair shops, software development companies and universities. Another non-production field in which lean is becoming increasingly relevant is the activity of developing new products. Conversely, there are some industry conditions which can impede the use of lean thinking. Lee et al. devised an “uncertainty framework” which indicates what type of strategy is most suitable for (members of) a supply chain. The horizontal axis represents demand uncertainty. Low demand uncertainty has characteristics such as predictable and stable demand, long product life, low profit margins, and low product variety. Conversely, products with high demand uncertainty have variable and unpredictable demand, a short selling season, high profit margins and high product variety. Supply uncertainty is found on the vertical axis. Supply chains with low supply uncertainty show less quality problems, more sources of supplies, more reliable and flexible suppliers, and a more mature production process than -31755257800Figure STYLEREF 3 s 0. SEQ Figure * ARABIC s 3 1 Demand and Supply Figure STYLEREF 3 s 0. SEQ Figure * ARABIC s 3 1 Demand and Supply -3175120967500supply chains with high supply uncertainty.Lee argues that only members of a supply chain with low supply and demand uncertainty should pursue an efficient, or lean, supply chain strategy. If there are uncertainties in the supply chain, these should be eliminated by uncertainty reduction strategies, before a supply chain can become lean. If uncertainties cannot be sufficiently reduced, a different supply chain strategy should be selected. To summarize, the literature shows that lean thinking can be used in a wide variety of industries. However, some external factors might prevent (a member of) a supply chain to become lean. These factors should be investigated before embarking on an effort to become lean. Size specific conditions Most research on lean thinking focuses on large organizations. As indicated before, due to lean thinking organizations are able to be more responsive to customer demand while requiring less equipment capacity and employ a more stable number of employees. Both elements, less equipment capacity and more stable number of workers are relevant for SMEs. SMEs generally do not have the financial capital available to acquire high 18 equipment capacity. Also, since SMEs often are family owned and have an (almost) family like relation with their employees, they generally aim to have a stable number of workers. Not having to hire temporary workers or having to fire people when sales are down being also less costly. This supports the assumption that implementing lean thinking is appealing for SMEs. White et al. have done a research about degrees of implementation of lean methods which shows a negative correlation between organization size and degree of implementation. It seems that smaller organizations are less able to implement a wide variety of lean methods, either due to a lack of organizational capability or financial resources, or due to an inapplicability of lean for smaller organizations. Rose et al. suggest that a lack of financial resources impedes lean implementation in SMEs and that SMEs should therefore focus on the methods which require little investment, such as 5S. Shah et al. have done a research which shows that when considering the combined effect of implementing different methods, large organizations are at a disadvantage. Smaller organizations seem to gain more operational improvement as an effect of implementing lean methods. Hence, even though smaller organizations implement less lean methods, they seem to be able to achieve superior performance improvements by the combined effects of the methods they implement. García et al. described a research which states that less focused on lean thinking, showed that SMEs can generate value by decreasing their inventory levels. Lower inventory level is a common effect of lean thinking. Based on the available literature it is difficult to state conclusively that lean is or is not particularly applicable for SMEs. Some research shows that smaller companies struggle more to implement lean methods. Other research reveals positive effects of lean in SMEs. This thesis aims to contribute to investigating if SMEs should pursue the implementation of lean thinking. The following section will describe the problems faced in implementing lean, the factors critical to successful implementation and various implementation methods. Finally, by evaluating the implementation methods by the critical success factors the most appropriate method will be identified. LEAN IMPLEMENTATION Implementing lean and achieving relevant results has proven to be difficult. Corboy et al. state that only ten percent of companies is successful when attempting to implement lean. One of the major barriers to successful implementation is the misapplication of tools. The misapplications can be of three kinds; using the wrong tool for a certain problem, using one tool to solve all problems and using all tools on every problem. Misapplying lean, manufacturing tools may waste additional time and money and it may decrease the confidence employees have in implementing lean manufacturing. The problems with the correct usage of tools shows that there is a need for guidance. For a lean implementation method to be useful it should at least offer this guidance. Below, critical success factors of improvement programs in general and for lean efforts specifically are linked to further implementation methods characteristics. Implementation method characteristics Indicate what tools to useA problem of lean implementations is that companies start with using one tool or a group of tools and push them through the entire organization. They then find out that their process does not improve.Hayes et al. studied that It should be taken into account that elements of lean tools and practices have systemic relationships and therefore cannot be implemented in isolation. Research shows that the effect of combined implementation of tools explain about 23 percent of the increase in operational performance. The critical number of implemented lean tools seems to be four. Companies implementing at least four lean tools show significantly higher productivity growth than their counterparts not implementing lean or not implementing enough lean tools. Merely starting with one of the popular lean tools is not sufficient. The implementation method should therefore take a holistic view of the process and indicate possibilities to implement various lean tools. Show benefits beforehand Emiliani et al. expressed that lean implementation efforts are tedious and require perseverance. On average, SMEs need three to five years to implement lean to a reasonable extent and to be able to maintain the effort on a long term basis. Portioli et al. emphasized that in SMEs as well as in large scale enterprises (LSEs), similar findings are reported for larger organizations Therefore, an essential factor in reaping benefits from a lean implementation is strong upper management 20 involvement. Furthermore, top management involvement is key in overcoming inevitable resistance to change, through leading. Sim et al. expressed that in order to convince top management, the initiative should have a clear link to the mission and goals of the company and it should be clear how the initiative will lead to a structural increase in profit. Preferably, the benefits of implementing lean methods are quantified before the actual implementation takes place. This allows management to understand the increase in performance when changing from the current system to a new, unknown system. Achanga et al. state that an implementation characteristic which holds the necessary changes to the process should be visualized to allow management to create a mental picture of the future process. This is especially relevant for SMEs, since they possibly have less opportunity to set up pilot programs, for instance in one department or on one production line. Such a pilot would possibly span the entire company, as SMEs sometimes only have one production line or department.Enhance cultural change Bhasin et al. described that critical for successful lean implementation is cultural change and acceptance of the new mindset throughout the organization. This change, and the acceptance of new tools, can be impeded by mistrust of employees. Kumar et al. experienced this in one of their case studies. Support of the production employees was achieved by convincing them their jobs would not be endangered by the lean implementation. Instead, they would be rewarded for improved performance. Karlsson et al. proposed a reward scheme aligning individual performance rewards with organizational goals. This element is more a managerial choice than a characteristic of an implementation method. It is included to emphasize the importance of cultural change. Summarizing, the implementation method indicates what lean tools to use where and visualizes the necessary changes, it quantifies the (financial) effects of the changes up front and possibly it supports the cultural change process. Implementation methods Various authors have proposed methods to implement lean thinking in organizations. The most important methods will have described and evaluated according to the characteristics as described before. Ahlström suggests that during the first phase of the project most focus should be on achieving zero defects and delayering the organization. Later, the focus should shift to continuous improvement. During the entire project, management should put efforts in eliminating waste, creating multifunctional teams, implementing pull scheduling, giving a lot of responsibility to team leaders, and instituting a vertical information system in which relevant information is shared amongst all employees. However, he does not offer a hands on approach on what tools to implement where and in what order. Neither does he propose a method to quantify the achievable benefits nor does his method include a clear visualization of the required changes or the potential benefits. Karlsson et al. proposed that companies should start lean efforts by implementing ‘quality circles’. These are small groups of employees who meet on a regular basis to discuss improvement possibilities. This increases the involvement of the employees in the lean implementation and subsequently the number of suggestions for improvement. Furthermore, for certain lean elements, such as ‘elimination of waste’, ‘continuous improvement’, or ‘multifunctional teams’, they identify key determinants and levels of implementation. This method gives some indication of how to increase the level of ‘leanness’, but lacks guidance in what tools to use or how to quantify the effect of the changes.Detty et al. proposed third method to implement lean is simulation. By modelling the current and future process and simulating them digitally, this method gives a precise prediction of the performance increase. The advantage of simulation is that results are detailed and offer strong insights in future performance. However, simulation is expensive and therefore possibly not practical for SMEs. Also, such simulation still requires an analysis of the system to choose what lean tools are needed. Simulation only provides validation of the expected results. Rother et al. described another method for companies to implement lean is Value Stream Mapping. The first step of VSM is to identify the current state of a selected process or product family. This results in a visual representation of all information and material flows and gives an insight of the ratio between value added and non-value added time. This current situation is then analyzed based on seven questions regarding the need and possibility of product flow in the process. This analysis results in a future-state map. The VSM process then analyzes what improvements should be made in the current process to enable the implementation of the future state. The final step includes planning and implementing the future state process. As described, VSM gives an indication of what tool to use where. The future state map is a visualization of the necessary changes and their effects. However, VSM lacks an evident connection to cultural change. METHODOLOGYThis section will describe the research strategy and methodology used to answer sub research questions. First, the considerations which are taken into account when choosing the research strategy will be discussed. Then, the research strategy will be developed further. Next, the VSM technique will be discussed in more detail. Finally, the data gathering methodologies will be described. RESEARCH STRATEGY The research strategy should have a number of characteristics. First, the research should take place in the context natural to the process, to be able to identify relevant contextual factors. Then, potential necessary data should be present and accessible to the researcher and the fact that the research is taking place should have a minimal effect on respective process. Finally, the research should be able to be performed during the time frame available for this research. These three characteristics are met by case study research. Gerring et al. defined a case study as “an intensive study of a single unit for the purpose of understanding a larger class of similar units. A unit evinces a spatially bounded phenomenon” This strategy distinguishes itself by examining a phenomenon in its real life context and therefore allows the researcher to understand what really happens in an organization and how processes lead to results. Case studies can combine different data collection methods, such as interviews, surveys, and observations. The gathered data can be qualitative, quantitative, or both. The possibility presented by case study research to understand a phenomenon in depth and to combine various types of data for different questions makes this strategy well suited for the combination of research questions researched in this thesis. The case study research strategy was heavily criticized as a strategy to develop relevant new knowledge. Critique was expressed in distinguishable terms. Such studies have such a total absence of control as to be of almost no scientific value. Any appearance of absolute knowledge, or intrinsic knowledge about singular isolated objects, is found to be illusory upon analysis. It seems well-nigh unethical at the present time to allow, as thesis or dissertations in education, case studies of this nature (i.e., involving a single group observed at one time only). Ellram et al. expressed that most critique revolved around two main assumptions about case studies First, case studies were thought of to only include qualitative data, which was expected to deliver less valuable insights. Second, case studies were seen as single data points, which limits the degree to which the conclusions of a case study research can be generalized. Work of various authors has shown that these assumptions are flawed and that relevant results can be obtained and valid theories can be developed through case study research. A variation of case study research is case-survey research. For this strategy, data of various cases is gathered and analyzed to draw conclusions about a certain phenomenon. As a result, this strategy could yield more statistically valid results. Two prerequisites for this strategy are that isolated factors are significantly interesting and that the number of case studies is large enough to be able to draw solid statistical conclusions. This research aims to capture various contextual elements of the lean implementation process and thus no single interesting factor can be isolated. Furthermore, the number of known cases of Indian SMEs implementing lean is limited. This leads to the conclusion that the two prerequisites are not met and the case-survey strategy is therefore not a viable option for this research. This study will therefore focus on a single case. The following section will describe the selection process of the case company. 3.2Case selection As described, lean manufacturing was primarily developed in the automotive industry. To be able to focus on the implementation method in SMEs, this research aims to research a case company which shares characteristics with this industry. This allows the use of the extensive literature about lean in such environments, without having to adapt the lean methodology to a significantly different field of use. According to Sugimori the companies in the automotive industry have to deal with a few distinguishing problems: Assembly of complex products consisting of thousands of parts, in high volume but with a large variation in product range, and high fluctuations in demand per product variation. Lasa et al. emphasized that they have to deal with relatively frequent tennis balls changes or renewal. Such companies can generally be categorized as discontinuous flow line manufacturing systems, where VSM was developed and where most results have been achieved with lean methods. If the case company is categorized as such, it is more likely that lean manufacturing methods are applicable, which is of course vital to this research. Furthermore, lean manufacturing was initially focused on increasing productivity and decreasing lead times. It is therefore preferred that the case company also predominantly has issues of these types. Finally, for considerations of generalization and relevance of the conclusions of the research it is preferred if the case company works in an industry which is relevant to the Indian economy. To find a suitable case company first an informal analysis of common production activities in the Indian economy was made. Prominent examples are machine production and metal processing. Through branch organizations and websites, and through the personal network of the author, various companies from these sectors were approached. Meetings with different companies resulted in a number of possible case studies. The company used as a case for this thesis was chosen, because they had lead time and efficiency, demand fulfilment issues, they were committed to improving their operations, and because they have a production facility in the India. Other companies were oblivious to their problems or had all production facilities abroad, which could both hinder the research. 3.3 Case company descriptionNivia Sports produces sprots goods for the different game industry around the world. They have a production facility in the India, with which they cater to the higher-end product range, and a wholly owned facility in India, where they produce a more basic product range. As such, both facilities deliver products globally, albeit most high end, more balls are delivered to customers in European, Asian, American countries, where labor costs are higher. At their production facilities, they assemble the sport products from parts delivered to them by various suppliers. NIVIA is a true Indian iconic sports brand involved in shaping the sports in the country. As the originator of breakthrough technologies, NIVIA manufactures world-class athletic equipment. High quality products at right price, superior design and integrated development make us second-to-none. Backed by generations of sportsmen, brand NIVIA has always challenged the unfamiliar and walked the less explored path to create opportunities for Indian sports sector. With state-of-the art facilities, NIVIA is Indian leading manufacturer of sports equipment, footwear & accessories for core sports like Football, Volleyball, Basketball and Running. Through continuous efforts in strengthening product innovation and enhancing R&D capabilities, NIVIA is set to achieve greater product differentiation and stronger product appealEstablished in 1934, NIVIA is now headquartered in Jalandhar, India with an employee force of more than 2000. Today, Nivia products are available in more than 1200 outlets across India. NIVIA is a Freewill Sports Pvt Ltd Brand.The production employees are multi-skilled and most of them are able to assemble sports products entirely or at least to a considerable extent. Some of the production employees also perform basic engineering tasks to improve product designs and technical drawings. The turnover rate of employees is very low. The machines of the company perform different, specified tasks in the production process of sport goods. These tasks are performed by hydraulically and electrically driven systems. These hydraulic and electric elements in the machines add to the complexity. The production volume is low and tennis balls are customized to customer order to some extent. The name and exact product of the case company cannot be disclosed due to confidentiality agreements. The complexity combined with low volume prevents the company from automating their production process. Therefore, labour costs constitute of a significant part of production cost. In light of growing global competition, the management of the company aims to improve production performance with productivity improvement. They have noticed that due dates are often surpassed while customers demand even shorter delivery times. Furthermore, the demand for sports goods built in the India is expected to increase. To meet this demand with the same personnel, productivity should increase. The management aims to maintain their production facility in the India, to keep a close link between production and product development. Their product development department is situated in the India as they find it easier to find qualified personnel there and due to issues with data and knowledge security in case of development in India. To be able to keep production in the India it essential to increase efficiency, to lower production cost, and to decrease delivery time. To improve production performance, the management has started a facility wide improvement effort, to which this research contributes. This research focuses on the production improvement. Applicability of Lean to understand if Nivia Sports is an appropriate case for this thesis, it will be compared to the various characteristics of potentially lean companies as described before. First, the case company should fall within the set delimitations. Nivia Sports can indeed be classified as a discontinuous flow line manufacturer and the company has production fulfilment and lead time issues. It therefore falls within the scope of this study. The volume and level of product variation at Nivia Sports are lower than in the automotive industry. On the other hand, Nivia Sports also has to deal with the problem of fluctuations in demand per product variation. This overlap in characteristics allows for the expectation that lean methods are applicable to this company. Finally, Nivia Sports should pertain to a supply chain which can be classified as an efficient supply chain in the uncertainty framework. The demand for each product variation fluctuates to some extent, but the total demand is rather stable. Innovations occur frequently, but they are generally improvements to current technology rather than technological breakthroughs. The margin on the products of Nivia Sports are high, but the product life cycle can be multiple decades. The demand uncertainty for the company is therefore considered to be medium. On the supply axis of the framework the following observations can be made. Most parts are fairly simple and the processes to manufacture them are mature. Also, all but one specific part can be produced by a wide base of suppliers. Breakdowns in this supply chain are limited and suppliers are generally dependable. Supply uncertainty can therefore have regarded to be low. The combined uncertainties in supply and demand lead to the conclusion that Nivia Sports is a member of an efficient supply chain. Some demand uncertainty reduction strategies might be useful to decrease demand uncertainty even further. Taking into account the various characteristics, Nivia Sports can be considered to be an appropriate candidate for this research. 3.4 DATA GATHERING To gather the required data, I observed during the production of tennis balls. I am able to perform all the tasks necessary to finish this type of operation. I focused on detailed and accurate data about the process. To support the observation process, an adapted version of the Process Activity Mapping tool was used. This tool allows me for process to take data about key information in a structured way. Each step in the process is written down separately, together with relevant data such as the time it takes to perform that step, the amount of people involved during that step. Furthermore, each step is categorized to differentiate between Value Added, Non Value Added and Necessary Non Value Added time. The categories, adapted to fit the work of the case company, are: Process: All the activities which add value in the eyes of the customer to the balls are included in this category. Move: Searching for and getting parts or tools. For this category, also the distance travelled is recorded. Install: As the balls need to be built with precision to work, it is necessary to position parts correctly respective to each other. These activities are necessary for the completion of the ball, but do not add value. Inspect: The production work in this facility consists mainly of curing, assembly tasks. This category includes all the work done to ensure incoming parts are fit for use. This consists of quality checks as well as corrective activities. Wait: Waiting, for example for tools or parts to be available, is recorded into this category. Consulting with fellow workers or management is also included. All data will be recorded in two ways, from the viewpoint of the employee and of the machine. In case of the machine, this means that the described action is performed on the machine. “Wait” then means that no action is performed on the machine during that period. The categories do not include all seven wastes. As all balls are not produced in order, there is underproduction. Furthermore, it is out of the scope of this research to investigate if the amount of processing and the precision applied are as the customer requires. During the observation period, improvement suggestions are identified and quantified in terms of saved time and walking distance. This offers additional improvement possibilities for the VSM analysis. The mere presence of an observer might influence the productivity of the employee under observation, which can endanger the validity of the gathered data. The effect of I is aimed to be minimized to have the highest validity of the data. First, an employee will be selected who is able to deal with the oddity of being observed while working. The selected employee is made to understand that he will not be judged on his performance as measured for this research. The employee will also get full insight in the data gathered and in the conclusions drawn from that data. The next section will elaborate on the VSM analysis of the case company3.5 VALUE STREAM MAPPING APPLIED This section will illustrate the results of the steps described in the methodology section. First, one product family is selected. Then, the current state is described and data is gathered to understand each process step in more detail. Subsequently, a future state is proposed accompanied by a description of the most important improvements suggested, and an implementation plan is offered. 3.5.1 PRODUCT FAMILY Nivia Sports has a variety of products, differing significantly in function. However, the production process across the different varieties is rather similar. Knowledge acquired about a certain product type can therefore be generalized to most other products. As a result, the choice of a specific product family was less critical in this case. As the chosen data gathering methodology was direct observation, it was essential that the chosen product was manufactured during the timeframe of the research. Second, all products are manufactured using the same (human) resources in the facility. Furthermore, the demand for most products is so high, that certain data, such as takt times, do not relate adequately to how the company serves its customers. Finally, the recommendations from this thesis will be applied to the entire production facility and this should be taken in consideration while performing certain analyses. It will be indicated clearly when analyses relate to the entire production facility.3.6 CURRENT STATE After the product family was selected, the current state of the process is described. First, takt time and other basic information about the process was gathered. Then, the process steps of production were described and data about each step was collected. Finally, information flows were analyzed. General process information The monthly production period of the company is 26 days. Over the span of this period 386540 balls are produced. Plant working duration is 54600 seconds per 2 shifts. There are total 2 shifts in a day (during 24 hours). So it is observed that time for morning shift and night shift are 28,200 and 26400 seconds respectively. This results in a takt time of 3.672 seconds per ball. Subsequently, the production facility should have the capacity to produce one ball in every 3.672 seconds. However, demand is not balanced evenly over the year. But during that year the average demand is estimated as 20000 balls per month. The takt time for this period is 2.73seconds. The facility should be able to cope with the ‘busy’ period demand and with the expected rise in demand One working day constitutes of 15 working hours and10 minutes. Breaks are not included in this period. Balls are shipped to the customer as soon as the balls, or total order consisting of a number of balls are finished. Value Stream Map All the information about the process is visualized in the following VSM diagram. To be able to relate to the quantities more easily, the times have been presented in seconds or hours. Figure 30.1 Current State Value Stream MapProcess steps The manufacturing process of ball consists of several discernible steps: Master batch mixing (MBM)It is a process of mixing of rubber with some type of chemical to enhance the property of the rubber and it also decreases the hardness of rubber and it would get soft by applying pressure at the time of operation which is performed by a machine called as Rula mixing machine. In this mixing process at the time of mixing a vulcanizing agent is mixed in to the base rubber with some types of colour according to customer demand. A lubricant is also provided at the time of mixing for overcoming the adhesiveness between rubber and rolls of steal. It also helps to remove the rubber sheet from the machine easily. The thickness and width of required dimension can be easily formed by the adjusting of gap between rolls. The raw material inserted in to this machine is depends upon the capacity, quality, power, and strength of the machine and it also depends upon the strength of the rubber. Generally, two operators are needed for this operation and one of them also perform sheet cutting operation when he is being idle. So for two continuous process including master batch mixing and sheet cutting operation only two workers cum operator are enough. From observation, Processing time of rubber in rula mixing machine= 595.79166 = 595.8 sec. In one cycle about 21 kg of rubber piece is used for master batch or rula mixing operation. Sheet cutting (SC)It is the type of a mechanical process in which a big sheet is cut into small pieces about 1-2 feet in length and about 1-1.5 feet in width with thickness of about to .5 inches. This process is fully manual. In this process a worker uses scissors to cut the big roll sheet of rubber which is already processed in master batch mixing. The weight of this big sheet is about to 21 kg. This big sheet is divided into near about 20 pieces. Weight of one small sheet is obtained by dividing the weight of a big sheet (released from master batch mixing) to the number of small sheets cut from it. From observation it is clear that weight of a small sheet=21/20= 1.05kg. And average cutting time which is taken by worker is 164 secs for 20 sheets, so cutting time for single piece taken by worker =164/20 =8.2 secondsPiece Cutting (PC)It is a semi-automatic process in which a rolling die cutter powered by an electric motor is used to cut the rubber sheet into small pieces whose average weight is generally depends upon demand and quality but also mostly pieces weight demanded in the range of about to 57.5 grams. The weight of piece is maintained by adjusting the die. For operating of this machine only one operator is needed. After cutting of sheets into small pieces, these small pieces are subjected to weighing process to fill the half core curing moulds. Half Core (HC) Making or Curing It is a process of making a half core of rubber by using die press. In die cavity we fill the piece of rubber according to the size and weight of the ball and then we apply the heat of steam with hydraulic pressure on it. By applying heat and high pressure it become soft and build up solid a solid rubber piece. In rubber we mixed the sulphur and heat it at high pressure then it forms a cross connection structure between elastomer and sulphur. This process done under high hydraulic pressure about to 1.5 ton/inch2. Steam is supplied under high temperature with high pressure about to 150±10 °C and 100 psi respectively. But in real situation temperature and pressure both are fluctuated due to heat rejection during transferring from steam generator to machine, in the form convection. Convection is a heat transfer under which heat is transfer from one solid boundary to the fluid boundary due to molecular momentum of fluid. The company uses three machines one of them has 192 HC capacity and remaining two machines have capacity of 144*2= 288 HC. Therefore, total capacity of the machines is 480 HC. The cycle time which is taken during this operation is equal to 515.226 sec. this cycle time is included process time loading and loading time also.Half Core CuttingIt is a process of cutting of half cores which are seemed as joined together after withdrawing from the half core curing machine. For cutting of half core or removing of half core from the sheet which is created after curing, is cut by hydraulic press by using the die whose shape is circular hallow ring, and these rings are fitted in a square box which contains normally 3*3 rings or 4*4 rings. It depends upon the no. of hemi cores which are joined together in a single piece of cured rubber of half core. If the size of half core sheet is 6*6 half cores or 8*8 half cores per sheet, then operator uses the 3*3 or 4*4 ring sized die. In half core cutting process kerosene oil is used on die for lubricant purpose which enables to ease withdraw of half core from die. Average cutting rate of half core is equal to 0.884 sec per HC.Half Core GrindingIt is a mechanical process which remove the unwanted material from the surface of rubber ball by using of a high-speed grinding wheel. A rubber grinding wheel consists of a steel wheel wrapped over abrasive paper. In abrasive paper coarse metallic carbide grains are pasted on a cloth and this cloth is further pasted on an annular steel wheel by using more valuable adhesive. This wheel is rotated by an electric motor. During grinding of rubber balls dust of rubber is created which is removed by a vacuum creation fan or exhaust fan. Generally, grinding is done to open the pours of half core. Half Core GluingIt is a manual process in which a worker dips the ring of half core in to the glue which is placed in a bowl. Gluing is used to joining of two half cores. This glue provides the adhesive property between two half cores made from rubber. A worker put the HCs on the belt drive for joining purpose. On belt drive these HCs are generally heated by hot air to dry the glue. The heating temperature varies from 40 to 45 ?C. For gluing operation at this time only one worker works to add glue on HC.Half Core JoiningHalf core joining of rubber ball is made by pasting of glue on the annular surface of rubber ball after it we put a very small tablet of chemical and water drop by syringe which the mixture of water and tablet created gas after heating or curing of full core, and it increases the co-efficient of restitution. After putting tablet and water inside the half core we align the annular shape of a pair of HC and it becomes like a sphere. And after that we put this ball inside a box for further process known as curing, each box contains 20 balls. Half core joining process is done on automated belt drive system inside which half core is heated about to 40-45oC. Heating is done to improve the strength of adhesive. After heating joining is take place. Gluing and joining both processes are established corresponding to each other. There is one man is needed for gluing and two men for joining including water, gas tablet inserting inside the half core, and these two men put these joined balls inside a steel box whose capacity is 20 balls. Filling in box is needed for curing of balls.Full Core (FC) CuringUnder this process, already joined pairs of half core are inserted in to the cavity of curing machine where these full core are heated under the high pressure with the help of steam. The temperature of steam varies from 130 to 160 oC and pressure of steam varies from 88 to 100 psi. Due to variation in temperature and pressure of steam the machine needed more time to heat it thereby cycle time of the curing is increased up to certain level. Increasing in cycle time productivity of a product is increased. In this process a hydraulic pressure is applied whose value is 0.5ton/inch2. Full Core GrindingGrinding is a process of surface finishing by abrasive particles with relative motion. It is done only when relative motion take place between work piece and tool. Tool is made by abrasive particles of carbide which are pasted at inner surface of cloth and this cloth is pasted on internal surface of a rotating drum inside which balls are filled. When abrasive cloth wrapped drum rotates then relative motion takes place between drum’s internal surface and outer surface of balls which are free to rotate, due to this finishing take place.Full Core GluingAfter grinding operation, it is needed to aid adhesive on the surface of ball for make to stick cloth on outer surface of balls easily. This machine is also like a full core grinding machine but main difference between them is rotation of grinding drum is vertical and rotation of gluing drum is horizontal. And a chief difference between gluing drum grinding drum is no abrasive cloth used in gluing drum. In a gluing drum we fill the full core and rotate it by electric motor at the time of rotation, an adhesive is squeezed by electric pump which is fitted. This pump lifts the liquid glue from low head to high dynamic head.Rula Mixing of Rubber Paste (RMRP) or Mixing of adhesive (MA)It is an operation to make the paste of adhesive rubber which is used to strengthen the bonding force between rubber ball and cloth. In this process paste is mixed by rula mixer with adding of some bleaching agents.Calendaring of Rubber Paste (RPC)It is a process to make the calendaring sheet of paste by rolling drum. The shape and size of calendaring sheet is depends upon the size and the shape of cloth sheet. In this machine a bulk material of paste is inserted into calendaring machine and this material passes through rolling cylinder to give the desired shape. Sticking of adhesive layer on cloth or Rubber Pasting on Cloth (RPC)In this process adhesive is added as a strip on sheet of cloth which is used for sticking it on outer layer of rubber ball. This adhesive increases the bonding strength between rubber ball and cloth. The standard size of cloth on which adhesive layer is pasted, is about to 80*50mm2. This machine is the type of roller mill, inside which we insert the adhesive piece and rolled it as a strip of adhesive which is automatically pasted on cloth due to rolling action. Because cloth is also inserted in to machine. This machine is a machine which is also used for calendaring of sheet. From observation we observed that the process time of sticking paste on cloth is about 9.45min for 100sheets of cloths or we can say that production rate is 10.58sheets/min.Punching of cloth Punching of cloth (PC) is done to cut the sheet of cloth according to required size and shape. The size and shape of punching die depends upon the size of ball. In punching machine, we use a hydraulic press which is connected to die, and this die further presses the cloth sheet and sheet become shear out. The shear out pieces are useful and remaining are scraps. Pasting of cloths on balls or Cloth Wrapping (CW)After punching of cloths other operation is done which is known as cloth wrapping on in process ball. Wrapping of cloth is done to improve the co-efficient of restitution. It is also done to improve the gripping property. The paste is added over the surface of cloth which is used to provide adhesiveness between cloth and rubber ball. This cloth also use for good looking of ball. In this industry this process is fully manually but some foreigner industries use the automated system to wrap the cloth on ball. But mostly small and medium size enterprises (SME) use the manual wrapping system are semi-automated system. Aligning of cloths (AC) on balls by rotating drumIt is a process which is done to align the cloth over the surface of tennis ball made from rubber. In this process, ball are filled inside a cylindrical box which is inclined between 30?-60? and it is connected to an electric motor via a bevel gear system, this gear system is used to transfer power between two non-parallel shaft with high speed reduction. When we on the power supply then that drum rotates and centrifugal force generated on balls which are filled on the cylinder, this introducing force generate pressure between internal layer of drum and external layer of ball due to this pressure cloth get equally distributed over ball surface and it strongly clinches the external surface of that ball. Rubber Band Pasting (RBP) on Balls.This process also known as rubber strip pasting. In this process a rubber wire is pasted over the surface of cloth wrapped ball to fulfil the gap between cloths wrapped. It also helps to make a bond between two consecutive layers of cloths. It disables to tear out the cloth due to notching. It strengthens the ball with increasing the toughness. It also improves the elastic co-efficient. Filling in Curing Box for Pressing (FCBP)This operation is done to checking the pressure wearing capacity of balls and also it helps to fit the balls in to curing box before inserting the box into curing machine for final curing. In this process a hydraulic press is used to press the balls which is powered by an electric pump. Some companies use the air compressor to press the balls. And also some manufacturing companies are uses mechanical press powered by quick return mechanism. But in those types of presses hydraulic press is better than other else because its accuracy is very high and controlling power is also very much. By these reasons this press is more efficiently used. Final Curing (FC)It is a process of heating of ball with steam to 15±5 min and after it get cool with water about to 20±5 min. heating is done at 150±10oC with high steam pressure which is about 100 psi. In this process a hydraulic pressure is also applied to hold the box and this hydraulic pressure also helps to active chemical reaction to create the good bonding strength inside the ball material. Final curing is done after pasting of cloths and rubber band to improve the toughness of ball. It also enables to enhance the bonding property between cloths and rubber ball. Steam BathIt is an operation to remove the dust from ball using steam flow. And also it used to swell the cloth which is already wrapped on the surface of ball, this cloth would become to shrinkage during final curing process. This process makes the ball beautiful and attractive. In this process a rotating drum is used in which balls are filled and this drum a steam flow pipe is connected. When we operate the system then drum rotates with electric motor and steam flows inside the cylinder and balls get wash out. Inspection and Finishing (IF)In this operation inspection of defects and finishing of ball both operation are simultaneously. On the basis of different types wastes like burry out, puncture etc. are identified and those defected ball separated from the non-defective balls. In finishing operation burr (raised edge or small piece of material remaining) are removed manually by tearing operation. In this over all process only visual inspection is done. StampingEvery company wants to promote own products by this prospective that company applies own stamp on the surface of ball. Stamp mark only shows that which company ball is used by you. It is semi-automatic process in which ball is put on s hemi-sphere and a printed stamp put over that ball then an air pressure is applied on ball and ink of stamp adhered on the external surface of ball. PackagingAfter stamping process balls are packed in wrapper by automatic machine. When balls are packed in wrappers then automatic cutter cuts the packets, and workers on that machine separate the pouch of balls. The workers visualize the wrappers in which balls are not packed and that wrappers are separated and reprocess is again done on those balls.DispatchingIt is an operation under which pouch of balls are packed according to company rule. But mostly company packs the balls in the product of dozen inside a box whose name in general form is cartoons. Sometime company pack the balls according to customer order. After dispatching process, these balls go to delivery via transportation system.Process data During the observation period it was also observed what actions were performed on various machines of the tennis ball manufacturing operations. At some point during the observation period a second production employee started to perform tasks on one of the machines. Recording the actions of both employees would have endangered the validity of the observations. The activities of the second employee were therefore not included.Discrepancies between times for different machines can have different causes. The fact that operation seems to have spent less time in the process is a result of not recording the actions of the second employee. Other differences are a result of the practical issue that I was not always present. Some activities for certain machines were performed when I was absent. The most apparent example of this is the difference in Install time. The Program step, which mostly included Install time, was only observed at machine As these observations are a combination of fragments of the manufacturing process of product tennis ball, it was necessary to combine the fragments to one generic process. This was done by lining up all the steps, which together form the process as if only one machine is produced, with the respective recorded distances and times. If process steps were recorded more than once, the average time and distance were taken. I have observed that the cycle time of FC curing, final curing as well as HC curing take more time. It happens because of fluctuation of steam temperature and pressure, steam is used to heat the rubber balls at high pressure. If we maintain the temperature and pressure at desired level then this type of problem would be short out. In this thesis I have make to try adding of some auxiliary devices in the curing machines to fix the temperature and pressure at constant level. Due to it temperature and pressure problem of steam is easily finished.By VSM it is clear that lead time and cycle time of different operations are very long. Defective pieces would be manufactured. The translation from the observation data to the generic process is prone to errors, thus verification of these data is required. However, triangulation of the data with data from the company was not possible, due to two main reasons. First, the company does not differentiate the time spent in different categories and some process steps are recorded collectively. Second, the data available at the company shows recordings of a period when the manufacturing process of tennis balls differed significantly from the current process. The data were therefore verified by the employee and his managers. They acknowledged the data and that they could be used for the remainder of the analysis. 188.8.131.52 Inventory levels There is more, or very large, inventory of finished balls. The vast majority of balls are produced to order and shipping is only delayed if other balls for the same customer are soon to be finished. Between the process steps, from Mechanic to Programming. For simplicity reasons, the process will be described as if only one employee works on the batch of balls. This is common practice in the facility. However, due to supplier issues delays often occur, resulting in additional waiting time for processes. As this extra waiting time is highly unpredictable, it will not be taken into consideration for the further analysis. Adding an arbitrary waiting time would cause discussion, distracting from the main analysis. Finally, there is inventory of rubber before the master batch mixing process step. To decrease transportation cost, material is stocked until a certain volume has been reached. Only then the materials are sent to the company which mixes them. On average, the materials are piled up for two days. Timeline The following step in the VSM process is to add a timeline, which shows the flow of balls through the process. The timeline differentiates Value Added time and (Necessary) Non Value Added time (NNVA). In high volume value streams the processing time, the time a part is actually in a machine or processed by an employee, is taken to be fully Value Added time. Non Value Added time mostly accumulates in inventory time and Necessary Non Value Added time in quality inspection at the end of the process. In the case of Nivia Sports a considerable portion of the NNVA time is found within the process steps. To clearly indicate this, the timeline for this case will differentiate Value Added time, Inventory time (IT), and NNVA time within the process. In this timeline Inventory time occurs after a process step, because this simplifies indicating that there is no Inventory time after the Programming step. Inventory time differs from Wait time, as Wait time occurs within the process step and Inventory time between two process steps. . Information Flows The sales force of Nivia Sports has close relationships with most customers and together they discuss the specific needs to which Nivia Sports can cater. Balls are customized to a certain level to fulfil the customer wishes. As this analysis focuses on production, the complex sales process has been left out of scope. The relevant information flow starts when a final sale is made and an order lead time is agreed upon. Normally this lead time is around three months plus transportation time from the factory to the client. Together with the CEO the sales force aims to predict upcoming sales of balls. This is then discussed in a monthly meeting between the CEO, the sales department, the production manager and the procurement manager. Together they decide what balls will be scheduled for production. This is put in the Manufacturing Resources Planning (MRP) system which then serves as an input for the procurement manager who orders products with the suppliers. The production manager bases the production plan on the MRP output as well. He communicates a daily and weekly production schedule to the production employees by a printed planning which is located centrally in the production hall. On a daily basis the production manager communicates changes in the planning, often caused by disruptions in the supply chain. Sometimes it occurs that the production planning is influenced by the CEO or the customer service manager. They receive inputs from clients and try to accommodate to their demands. FUTURE STATE The result of the previous section is a detailed description of the current state of the process. The visualization of the process indicates that there is potential for improvement. This section will first discuss the eight guiding questions for the future state analysis together with the improvement suggestions for the process. Finally the future state map is presented. Figure 3.2 Future State Value Stream MapThe implementation plan will be discussed in the following section. Guiding questions each of the eight guiding questions will be discussed separately in this section. What is the takt time? Takt is a German word that means beat. In essence, Takt is the beat of the line or cell; it is the speed that this value stream must operate at to keep pace with demand. Mathematically, Takt Time=Net available timecustomer demand in that periodAs discussed in the Current State section, the company does not have a constant demand throughout the year. However, since the facility should not be able to cope with ‘peak’ demand and demand is expected to rise, a takt time slightly higher than current ‘peak’ takt time is used for the future state map. As stated before, the used takt time is 3.672 seconds per ball. By improving the production system the takt time decreases to 2.93 seconds.Finished goods supermarket or direct shipping? Most balls produced by Nivia Sports, especially in the Indian facility, are built to specific customer orders and customized when needed. This means that there is no use for a finished goods supermarkets and therefore balls are shipped directly after manufacturing has finished. Where to use continuous flow? Continuous flow is possible downstream from the Subassembly step. From that step onwards, all production may be a one piece flow or batch flow. The flow of materials from local suppliers, some of which have to be blackened, should also link closer to the production pace and order of the main process. This requires more frequent deliveries, especially to and from that company. Where supermarkets? A supermarket system with half cores and full cores would greatly decrease delivery lead time. However, currently the variety of HC and FC prevents the company from doing so in a financially responsible manner. The amount of stock needed would be excessive. In order to make this a viable option, the company should increase their current effort to decrease the amount of varieties. This would in turn allow for an inventory of HC and FC to be held in the Indian facility. Orders for new casings and structures would then place with the Indian subsidiary to refill the supermarket. Pacemaker process? The pacemaker process is where the schedule is imposed on the process. Generally it is the most upstream process of the continuous flow, which in this case is the Subassembly step. Conversations with the production manager and production employees revealed some practical issues with electing the Subassembly step as the pacemaker process. Primarily this concerned the fact that production capacity at the Subassembly step can be changed promptly, by assigning more or less human resources. This is often necessary, because most production employees also fulfil tasks aside production. Furthermore, they indicated that it was easier to understand a production pace of different type of balls every week than a pace of a varying amount of subassemblies to be produced every week. This amount varies, because the number of balls per variety and the production time per variety varies as well. It was therefore decided the Mechanic step will be the pacemaker process and the Subassembly step will be scheduled according to the available capacity.How to level production mix? As the analysis focuses on tennis balls, there is no need to level the production mix. However, a wider variety of balls should be taken into consideration, because in the long term the entire production facility is aimed to be organized as the proposed future state map. Then, production mix should be levelled. Conveniently, this naturally happens by the nature of demand for the products of Nivia Sports. Customers either require small amounts of similar balls or, and this happens more often, they need different balls in one order. By planning production in the order in which balls are sold, production is already levelled to a great extent. What increment of work? Generally the increment of work released at the pacemaker process is a multiple of the takt time. In this company, after using of improvements takt time may decrease up to 2.93seconds. It means that in a desired time span more balls are produced. Hence it is proved that increment in work take place. It would be favourable to release smaller increments of work in order to have a more frequent feedback about progress. However, the nature of the work prevents that. An indication could be given per step what progress should have been made after a certain amount of hours to give intermittent feedback. What improvements are needed? This section will describe the key improvements relevant for the entire process. The following section elaborates on the improvements within the process steps and the subsequent possibility to rebalance the production process. Produce to takt time: To cope with future demand the facility should produce one ball in every 2.73sec. but after applying lean thinking we produce only 2.93sec as takt time. This pace should be set for the entire production facility. This is commonly achieved by organizing production in a line configuration. The different process steps get specific workstations and the tennis balls pass each workstation. On average in every 2.93sec, all balls are moved to the next workstation.Schedule at specific steps: As described, scheduling will be needed at four steps. It is key to only schedule at these four steps. The rest of the process products should flow through the process in a ‘First In First Out’ (FIFO) order. This makes the process predictable. Supermarket of Rubber: In order to decrease delivery lead time substantially, it is necessary to have some inventory of parts in the facility. This is especially relevant for products which need to come from other states by transportation. Further rationalization of ball design is needed to achieve this. Stable delivery of balls: As the company will be producing at a fixed pace, the delivery of balls should be at a stable, dependable pace. Balls will also need to be delivered in the correct order. If balls are delivered at a steady pace and in the right order, they can be delivered just in time for when they are needed. This decreases handling time of those balls within the facility of Nivia Sports. Process step improvements During the observation period, various possibilities to increase performance within the process steps were identified. To check the viability of the suggestions, they were discussed with different employees of the company. The main categories of improvements are: Quality of incoming material: On a regular basis throughout the entire process incoming materials need adjusting to be usable. This is either a result of poor supplier performance or of suppliers provided with faulty order information. Correct electronic schemes: Mistakes in electronic schemes occur sporadically, but when they happen they cause major disruptions in the production process. It is hard to recognize that a problem is caused by an error in the electronic schemes rather than by a physical inaccuracy in the machine. Then, when it becomes apparent an error in the electronic schemes is the cause, it takes time to identify the exact mistake. Clear work instructions: Since demand for specific types of balls is high, employees encounter specific balls types irregularly. This means it takes time to remember what steps to take. Some employees keep personal work instructions, but these are not commonly shared and are often not complete. A common work instruction would decrease the time employees spend on thinking what to do next and on updating their personal work instructions. Place in process material closer to workstation: Employees need a considerable amount of time to locate and get the necessary parts. Parts are placed in a confused way in the production area without indications of which parts are where. Parts intended for a specific process should be placed together on one or two carts which have clearly indicated for what orders those parts are needed. These carts should then be placed close to the workstation where they are needed. Furthermore, parts should only be released to the production area when the production of the respective tennis balls requires them. Workplace design: Currently workstations are not designated for a specific function within the production process. As a result, employees all have a fully equipped tool box, making it hard to find the correct tool quickly. Specific tool ‘plates’ should be designed per workstation. Furthermore, each workstation should have waste bins located closely, to reduce cleaning time. RESULTS DISCUSSION AND SUGGESTION By following the proposed implementation path of the improvements, the performance of the production process can be improved. This will allow Nivia Sports to cope with the expected increased demand with the same people using the same space. Expected results for some key parameters are presented in the following table:Table STYLEREF 1 s 0 SEQ Table * ARABIC s 1 1 Sr. No. Performance Indicator Current Future Percentage Change 1 Total worker 46 44 4.3482 Total work content (sec) 4181.1655 3817.33 8.7023 Necessary Non Value Added (NNVA)Time 83.375 83.375 0.0004 Value Added (VA) Time 8125.0235 6622.57 18.4925 Non-Value Added (NVA) Time 55131.012 29378.2 46.7126 Production (Number of balls/day) 14867 18636 25.3517 Talk Time (sec) 3.672 2.93 20.2078 Distance travelled (ft) 369 369 0.0009 Production percentage w.r.t. estd. demand 74.335 93.18 25.35110 Total Lead Time 63256.0355 36000.8 43.08711 Percentage of VA time to NVA time 14.7376643 22.5425 52.95812 Productivity in terms of production and worker 323.195652 423.545 31.049Little’s Law states that the amount of work in progress equals the lead time divided by the takt time (Little, 1961). In the current situation this results in an average work in progress having LT = 1.1585 days, takt time = 3.672sec/ball. This is in line with the general image one gets by visiting the factory. In the future state this lead time and takt time can be reduced to 0.659 days and 2.93 sec respectively. This is a reduction of 43.087% and 25.351% respectively.Line BalancingAccording to this method firstly we calculate the line efficiency of production line which states that how much profit generated against invested cost. It may be reduced by reducing of number of workstations. The number of workstations are reduced by eliminating not necessary process or by combining of sub workstations in to a main workstation. Typically,This method is used to reduce the idle time. Due to decrement in the idle time of the production line, the lead time of production line also decrease and also it decreases the cycle time indirectly. By these things of time reduction, the number of cycles produced in a day may be increase and that’s why productivity may be increased.Fig. Line-balancing chart aligned underneath the Current State Map Fig. Line-balancing chart aligned underneath the Future State Map Overall Equipment Effectiveness (OEE)OEE is an abbreviation for the manufacturing metric Overall Equipment Effectiveness. OEE takes into account the various sub components of the manufacturing process – Availability, Performance and Quality. After the various factors are taken into account the result is expressed as a percentage. This percentage can be viewed as a snapshot of the current production efficiency for a machine, line or cell.OEE = Availability *Performance *QualityOEE of two machines are given as follows. OEE is very low so improvement is needed in these two machines.COMPANY DISCUSSION The most relevant results for the company are the reduced time needed in the different process steps and the decrease delivery time. By reducing the total work content of the process, the same number of employees can build more balls. Decreasing the lead time makes the company more responsive to customer demand and diminishes the need of forecasting demand. This reduces the risk of stock-outs or of obsolescence of parts. Prior to the research, the management of the company set goals for these two parameters. The aim was to achieve demand and to increase productivity. Even though the goals were set arbitrarily, it is relevant to understand if the VSM method indicates enough improvement potential to satisfy the company. Improvement suggestions have the potential to decrease the work content of the observed part of the process by 8.702 percent. This increases the employee productivity with the 31.049 percentage. The improvement is considerably more than aimed for and the managers were surprised by the amount of waste found within the process steps. Unexpected insights 55 especially came from the amount of time wasted due to problems with incoming material and by walking through the facility to find tools and parts. Further suggestions allow the delivery time to decrease substantially. The lead time within the premises of the Indian facility can be reduced by at least 43.087 percent, mostly by implementing continuous flow. This reduces the inventory time of balls. The VSM diagrams proved to be a powerful tool to convey this message. At first, the suggestion of production in a line was countered by the argument that manufacturing of balls in a batch allow for faster manufacturing, due to learning effects. If someone has, for instance, just performed the hydraulic pressing step at one machine, it will take less time for the following balls of that batch. The VSM analysis showed that a shift in mind-set was needed around this topic. Furthermore, it was observed that the lean initiative was welcomed by most production employees. They felt that the issues they encountered in their daily work were now recognized and that an effort was put to structurally improve the process. Their scepticism about the longevity of this effort should be overcome by perseverance. As most of the implementation is planned to happen after this research, it is not possible to understand the effect of this effort on employee satisfaction. Some employees might lose a sense of being indispensable, as more tacit knowledge is converted into explicit knowledge. Also, employees might lose some freedoms they currently have. For instance, employees are now allowed to decide how many hours they work each day, as long as they work ninety four hours each week. This might become problematic when producing to takt time. It is essential to manage this influence carefully. Parallel to this Value Stream Mapping analysis a lean consultant was supporting a companywide lean effort. His implementation method was based on the fifth approach described in the Lean implementation section, starting with creating awareness, followed by 5S. It was interesting to see how this approach struggled to convince the employees of the necessity of change. It became clear that the measurements about time wasted, machines waiting, and distance travelled from this research were more appealing to the employees. The lean consultant changed his approach to one more alike a VSM analysis. It was evident that this increased employee engagement and enthusiasm. The effect of this implementation on product quality is not taken into consideration, because I has no insight in the quality standards to be met. However, it is hypothesized that the introduction of standard work instructions may have a positive effect on quality performance measures. It should be noted that most improvements do not offer a direct increase in profitability, mostly because the production staff cannot be decreased in size. Increased profitability is to be reached by ensuring the same facility is capable of coping with an increase in sales. Finally, several discussions with management and employees allowed for confidence that the analysis focused on this specific product family can be generalized to the majority of the entire product range produced in the Indian facility. GENERAL DISCUSSION In order to understand the relative value of the potential improvements the results should be compared to results attained in other cases. However, this is complicated by two main concerns. First and foremost, there are few published examples of case studies in comparable production environments to be used as a benchmark. Second, the level of potential improvements depends strongly on the initial state of the considered process. There is no clear benchmarking model to compare the initial states of different processes. To get some indication of what is considered to be a successful lean implementation, the potential improvements at Nivia Sports regarding lead time and productivity are compared to two measures.Lathin and Mitchell (2001) claim that any traditional mass producer should be able to decrease lead time by 90 percent and increase labour productivity by 50 percent. Even though Nivia Sports is not a mass producer these improvements serve as some indication. Gates (2004) performs a VSM analysis in a single department of a high-mix/low-volume environment, which could be considered relatively similar to Nivia Sports. He finds a potential lead time reduction of 67 percent. Labour productivity of the observed process can be increased by 31.049 percent. This too comes within reach of the potential Lathin and Mitchell (2001) assume. It is hypothesized that the high fraction of manual labour applied in Nivia Sports and the fact that they have no setups limits their potential improvement. To understand if the analysis of the production of tennis balls at Nivia Sports offers sufficient potential the improvement potential was compared to management’s expectations and to measures from the literature. Both comparisons indicate that the found potential can be considered to be substantial.Suggestions.Using of Auxiliary DevicesIt has been seen that in the process of curing, the machines take long time to cure the balls. Also half core curing machines, full core curing machines, final core curing machines take long time to perform these processes. These process takes long time whose main reasons are fluctuation in the temperature and pressure of steam which is supplied to these machines for heating purpose. I have seen many times that temperature and pressure are below desired level due to which the time taken by machines to cure these balls is long. Steam generator is for away from the curing machines, and steam flows from pipe get loss own energy to the atmosphere in the form of convection and radiations. Due to heat loss to the atmosphere, temperature of steam decreases with the increasing the distance of pipe. There, the distance between curing machines and steam generator is very high. This distance is kept more so that the effects of temperature or fire, blast accidents can be prevented. Overcoming the temperature and pressure fluctuation we suggest to add of auxiliary device in the curing machines to reduce the cycle time. There are many auxiliary devices suggested which are based on following system.184.108.40.206 Open Loop Control SystemIt is the most fundamental form and applies ceaseless warming/cooling with no respect for the real temperature yield. For instance, it is comparable to the inside warming framework in a car. On a cold day, you may need to turn the warmth on to full to warm the car to 75°. In any case, amid hotter climate, a similar setting would leave within the car considerably hotter than the coveted 75°.Figure STYLEREF 3 s 0. SEQ Figure * ARABIC s 3 1 Block diagram of Open loop control system220.127.116.11 Closed Loop Control SystemClosed loop control is much more sophisticated than open loop. In a closed loop application, the output temperature is always estimated and changed in accordance with keep up a consistent output at the coveted temperature. Closed loop control is constantly aware of the output signal and will encourage this over into the control procedure. It is closely resembling a car with inside atmosphere control. On the off chance that you set the car temperature to 75°C, the atmosphere control will naturally change the warming (amid chilly days) or cooling (amid warm days) as required to keep up the objective temperature of 75°C.Figure STYLEREF 3 s 0. SEQ Figure * ARABIC s 3 2 Block diagram of Open loop control systemNow a day mainly closed loop control system is used due to compact shape and precise control. It is more effective than open loop system. Some example of closed loop control systems are given below:18.104.22.168 PID ControllersA proportional– integral– derivative controller (PID controller or three term controller) is a control loop criticism component broadly utilized as a part of modern control frameworks and an assortment of different applications requiring consistently balanced control. A PID controller ceaselessly ascertains an error value e(t) as the distinction between a coveted set point (SP) and a deliberate procedure variable (PV) and applies an amendment in light of corresponding, essential, and subsidiary terms (signified P, I, and D individually) which give the controller its name. In pragmatic terms it naturally applies precise and responsive remedy to a control work. A regular case is the voyage control on a street vehicle; where outer impacts, for example, slopes would cause speed changes, and the driver can modify the coveted set speed. The PID calculation re-establishes the real speed to the coveted speed in the ideal path, immediately or overshoot, by controlling the power output of the vehicle’s engine.The first full PID controller was developed in 1911 by Elmer Sperry for the US Navy to automate ship steering. Sperry designed his system to emulate the behaviour of the helmsmen, who were capable of compensating for a persistent variance, as well as anticipating how the variance will change in future.Figure STYLEREF 3 s 0. SEQ Figure * ARABIC s 3 3 PID ControllerWhere,P= Proportionality functionI= Integral function D= Deferential functionr(t) = Set pointe(t) = Error value functionu(t) = Controlled variable y(t) = Process variableThe recognizing highlight of the PID controller is the capacity to utilize the three control terms of proportional, integral and derivative effect on the controller output to apply exact and ideal control. The square graph on the correct demonstrates the standards of how these terms are created and connected. It demonstrates a PID controller, which persistently computes a error value e(t) as the distinction between a coveted set point (SP=r(t)) and a deliberate procedure variable PV=y(t), and applies a remedy in light of relative, indispensable, and subsidiary terms. The controller endeavours to limit the error over by alteration of a control variable u(t), for example, the opening of a control valve, to another value dictated by a weighted aggregate of the control terms. In this model:Term P is corresponding to the present estimation of the SP???PV error e(t). For example, if the error is substantial and positive, the control output will be proportionately huge and positive, considering the gain factor “K”. Utilizing relative control alone in a procedure with remuneration, for example, temperature control, will bring about a error between the setpoint and the real procedure value, since it requires an error to create the corresponding reaction. On the off chance that there is no error, there is no restorative response.Term I represents past estimations of the SP???PV error and coordinates them after some time to create the I expression. For example, if there is a leftover SP???PV error after the utilization of relative control, the basic term looks to take out the remaining error by adding a control impact because of the noteworthy aggregate estimation of the error. At the point when the error is disposed of, the indispensable term will stop to develop. This will bring about the relative impact lessening as the error diminishes, yet this is made up for by the developing indispensable impact. Term D is a best gauge without bounds pattern of the SP???PV error, in light of its present rate of progress. It is now and then called “anticipatory control”, as it is successfully trying to diminish the impact of the SP???PV error by applying a control impact produced by the rate of error change. The faster the change, the more prominent the controlling or hosing effect.22.214.171.124 Temperature Controlling DeviceThese type of devices are those type of devices which are used to control the temperature within the prescribed range by feedback control system or error detection system. As the name counsels, a temperature controller is an instrument used to control temperatures, for the most part without extensive operator involvement. A controller in a temperature control framework will acknowledge a temperature sensor, for example, a thermocouple or RTD as input and compare the real temperature with the coveted control temperature, or set point. It will then give an output to a control element. A decent illustration would be an application where the controller takes a contribution from a temperature sensor and has an output that is associated with a control component, for example, a radiator or fan. The controller is generally only one part, in a temperature control framework, and the entire framework ought to be examined and considered in choosing the best possible controller. Figure STYLEREF 3 s 0. SEQ Figure * ARABIC s 3 4 Temperature Controlling Device126.96.36.199 Pressure Controller Devices1301754880610Figure STYLEREF 3 s 0. SEQ Figure * ARABIC s 3 5 Pressure Controller DevicesFigure STYLEREF 3 s 0. SEQ Figure * ARABIC s 3 5 Pressure Controller Devices13017517316450Devices which are used to control the pressure of fluid within prescribed range. These type of devices used to maintain the constant level of fluid supply in the machine by virtue of which it resists the fluctuation of pressure, caused by temperature decrement or due to leakage, it is also caused by throttling process. Throttling process occurs inside the valves. On the basis of open loop ; closed loop control system, many devices are used. But closed loop controlled pressure devices are better than open loop controlled devices. Note- Some minor improvements, such as adding of auxiliary devices known as temperature and pressure controlling devices which are used to maintain the constant temperature and pressure, these types of devices can reduce the cycle time of curing process which occur due to fluctuation of temperature and pressure. Continuous ImprovementVarious improvements deal with disruptions which happened during the observation period, especially in the ‘Quality incoming material’ and ‘Correct electronic schemes’ categories. These highly unpredictable events greatly affect the total process time and can disturb this analysis, because those specific events might not repeat itself. However, several employees and managers recognized that this type of events occurs during the production process of balls. It is observed that if you maintain the machines by oiling, proper maintenance, then breakdown chances of machines are reduced due to which machines work properly for long time. Employee skill improvement programme must be done time to time for improving skills of employees. Using of good quality of grinder should be used for decreasing the cycle time and increasing the finishing quality in grinding machines. It would be also suggested that use the qualitative parts in machines like curing machines.Improvement of Incoming MaterialsI was not able to differentiate the causes of unsatisfying quality of incoming material, because employees were not always aware of which supplier delivered a specific material or if the order sent to the supplier was correct. Both should therefore receive attention in the improvement effort. To increase the quality of balls, quality of rubber, paste and cloth must be good. In-process InspectionIn this process we inspect the defects after each process and find out the causes of defects. After finding the causes of defected balls, we should search the technique to overcome that types of defects. The improvements will affect the time needed for each process step. Also, the percentage of Value Added Time will increase. Some NNVA activities seem to be inevitable after this improvement effort. This is especially due to alignment tasks and quality inspection tasks currently necessary to meet the required quality standards. Proper Filling of Rubber in HCs Curing MachinesMost of defective pieces are produced due to uneven filling of rubber in curing machine due to which some core are produced under loaded (lighter) and some are over loaded (heavier) than set limit. Those balls are struck out from the lot and these types of ball are sold at very low price without company’s stamp. It is a part of loss. So we suggest to fill the cavity of HCs curing machine very well to overcome that type of loss.Using of Cloth Wrapping Die It is a type of hemispherical designed of two parts inside which we place the cloth firstly then we put the FC, after putting FC properly we apply a force to press the ball. By pressing the ball, it becomes cloth wrapped. It takes less time than manual wrapping. Normally it takes about to 15 sec to perform this action. Facility Layout Improvement center2619375In this manufacturing plant various processes do not having good layout due to which more travelling distance created and some time they created inventory handling problem. These two main problems increase the process lead time. Transportation is a necessary non-value added (NNVA) activity. At this time in that plant continuous flow does not occur. The current layout of plant is given as follows:1’= adhesive mixing2’= adhesive pasting on cloth3’=cloth punchingIn this different colours thatBlue= rubber material at ground flourleft706755000Black= adhesive paste at ground flourMaroon= cloth at ground flourPurple= adhesive pasted clothRed= cloth pasted ball at ground flourGreen= processes at 2nd flourPink= storage at 1st flour Value Stream Map, Future StateAll proposed improvements and changes result in the following future state map. A customer finalizes an order with the sales department, which puts this order in the MRP system. The procurement manager then orders the necessary items with various suppliers. These items are either transported by road transportation or through the milk run to Nivia Sports. When all items have arrived and a possible queue in front of the production processed is empty, the tennis balls are produced by various employees in predefined takt time. All balls are placed on designated carts and placed close to the various work station. Balls are then processed at the different workstations, taking different time at each station. When the cloths and rubber elements are taken from the supermarket, the procurement manager places a replacement order. After each day of manufacturing inside the Indian facility, the balls are ready for transportation to the customer. Normally, improvements to the process are indicated in the future state map. For clarity reasons, the improvements have been omitted in this diagram.IMPLEMENTATION Previous sections have shown improvement suggestions for the manufacturing process of tennis balls of Nivia Sports. This section will elaborate on the practical interventions and implementation. There are some prerequisites which enable production at a fixed pace with continuous flow. In collaboration with different managers of Nivia Sports the following implementation plan was developed. Each step will be discussed in some detail, including reasoning for the order of implementation and practical steps to be taken. Dependable suppliers Currently, a factor preventing paced production is poor performance of some key suppliers. These suppliers deliver parts late, in erroneous quantities and of poor quality. Due to an intimate historical relation with these suppliers and the protection of some competitive knowledge this substandard performance has been allowed the past years. To improve the quality and dependability of supplies, the following steps were, or are currently being, taken: A tool has been put in place to measure faulty or late deliveries and to record quality issues. The performance data will be published within the company on a regular basis as well as discussed with the respective suppliers. The suppliers have been notified about the concerns around their performance, and that from now on the performance will be measured and discussed with them. Contact with these suppliers has been intensified to identify problems and to instruct them more clearly. To depend less on this small group of key suppliers, it is currently being investigated if orders can be diverted to other suppliers, for instance to the other state subsidiary. Only if the supplier issues have been sufficiently tackled it will be possible to go from the current, faithless production process to a stable, paced process (Karlsson ; Åhlström, 1996). This intervention can be seen as a supply reduction strategy as proposed by Lee (2002). It is expected that improved supplier performance will lead to the required decrease of work content in the Subassembly step. A variation of the proposed milk run for local suppliers has been implemented, which reduces the specific inventory.Reduce the eighth waste Through numerous talks with production employees during the observation period it became clear that the employees have many relevant ideas for improvement. However, most of these ideas are not converted into action, lowering the morale of the employee with the idea. On the other hand, the managers feel that problems are only mentioned vaguely with the expectation the managers offer instant solutions. To support the flow from ideas on the production floor to actual action an improvement form was introduced. On this improvement form employees identify a problem and the solution they propose, including a rough financial implication. After handing this form in, the manager of the respective department has to report back to the employee within ten working days about whether or not the solution will be implemented and why. Every month data is published within the company about the number of proposed ideas, the percentage implemented, the percentage of ideas handled within ten working days, and a progress report for the ideas which are being implemented. The first ideas, ranging from unblocking safety routes to improving packaging of tennis balls, have been implemented. An effort will be necessary the coming months to increase the flow of ideas. As a part of this effort, the CEO will work on the production floor one day every two weeks. Each time he will work with a different employee to better understand issues and improvement possibilities throughout the entire process. Workplace improvement The workplace can be improved by making tools and parts easier to find, and by locating them closer to where they are needed. To achieve this, several steps are currently underway: The carts used to stock parts between the in process line will be designated to a specific order, indicated by a paper attached to the cart. The carts will be placed close to the specific workstation, to reduce travelling distance and time. Together with two production employees an analysis was made of what tools are necessary per workstation to perform all the tasks. This clearly showed that their tool boxes were overly filled, making it difficult to find the right tool. Special tool tables will be made, including the tools required at a specific workstation. The tool tables will also hold specific materials necessary at the workstation, such as plier and scissors. Tools needed to repair incoming material, such as quality testing equipment, will be located in the production manager’s office. This intervention makes it evident to the manager every time there are quality issues with incoming material and should lead to stricter control of supplier performance. These improvements are currently in process to prepare the organization for a paced production process. They should be implemented before a following batch of tennis balls will be manufactured. A paced process will be introduced with a pilot of that batch of tennis balls and this will be followed by more improvement implementations. Paced production An initial of paced production will be done with one batch of tennis balls. At first the pace might be slightly lower than the takt time. Lessons drawn from the first batch will serve as input for further improvements. The pilot is also a way for the employees to get used to this way of working. After the initiation, other product types with similar amounts of work content will be added to this process while maintaining the effort to reduce waste. Finally, also products with less work content will be manufactured by this process. The few products with substantially more work content will be produced in a different area of the production floor. By also mixing lower work content machines in the queue, employees will have time to fulfil their non-production tasks, such as engineering, on a regular basis. Currently, the engineering tasks are delayed often under pressure of due dates, resulting in outdated technical drawings and electrical schemes, with connected delays in production. This extra time can also be used to write uniform and up-to-date work instructions. Machine redesign The final, and most long term, effort will be to redesign the total product range in such a way that it is viable to keep stock of balls in the Indian facility. The future state VSM gives a clear insight in the positive effect of this effort.CONCLUSION AND IMPLICATIONS This section will first answer the three sub research questions. Combining the answers for these questions will lead to a conclusion concerning the main research question of this thesis. Then the generalizability of the results will be elaborated upon, followed by a brief discussion of the academic relevance and the managerial implications of this thesis.RESEARCH QUESTION The purpose of this thesis was to understand if the Value Stream Mapping method is an appropriate method for Small and Medium Enterprises to become more productive and to respond more adequately to customer demand. To answer the research question, three sub research question were proposed and answered in this thesis. First, it was essential to understand if lean thinking is applicable to SMEs. Extensive literature review gave an ambiguous answer. Based on the results lean thinking commonly yield, it seems that lean is an interesting approach for SMEs. Various investigations show that lean implementation in SMEs is less common and less extensive than in large organizations. Other research shows that while SMEs generally implement less lean methods, they benefit more in terms of productivity. Several case studies of lean implementations in SMEs show what results can be attained by implementing lean thinking. This thesis on its own is an example of potential improvements which can be revealed by lean methods. It can therefore be concluded that lean thinking is an appropriate production methodology for SMEs, at least under certain conditions. Then, the most appropriate lean implementation method for SMEs was selected. Critical success factors for lean implementation found in the literature where translated into essential characteristics of an implementation method. Different implementation methods were described and discussed according to the essential characteristics. From this analysis VSM emerged as the most appropriate tool. This method lacks an explicit focus on necessary cultural change. However, it was hypothesized that the clear visualization of occurrences of waste can instigate sufficient understanding among the workforce. This was indeed experienced in the performed case study. After concluding that lean thinking can be applicable to SMEs and VSM that seems to be the most appropriate implementation method for SMEs it was investigated what results can be attained by the VSM method in an SME. It was decided to use a case study as the research strategy. This allows for detailed understanding of the implementation process and the connection to its natural context. A case company was found in one of the relevant sectors of the Indian economy. The company meets the requirements to become lean and fits the delimitations of this study. The VSM method was performed on the production process of a specific product family in the case company. Through informal talks and direct observation of the production process data were gathered about the entire value stream. The Process Activity Mapping tool was used to enhance the richness of the gathered data, by classifying all separate actions in different categories. During the observation period, suggestions for improvement of the process steps were recorded. Combining the recorded suggestions with the prescribed VSM analysis resulted in a proposed future state of the production process. A plan was presumed to guide the implementation of the process changes. Comparing the proposed future state with the current state gave insight in the potential improvement regarding different process parameters, such as work content, delivery time, and in-factory lead time. The revealed potential exceeded management expectations and some unexpected insights were gained. To value the relevance of the exposed potential, the gains were compared to measures found in the literature. The improvements approach goals set for traditional batch producers and exceed the potential found in a relatively similar case. Even though the used measures are far from universally accepted, the benchmark does seem to indicate that the found improvement potential is substantial. To summarize, it can be concluded that lean can be applicable to SMEs. Furthermore, evidence is provided which supports the conclusion that VSM is the most appropriate lean implementation method for SMEs. It is also concluded that reducing of wastes by using of auxiliary devices and various improvement, enhances the productivity. Finally, the improvement potential found by the VSM method is substantial. Together, the conclusions for the different sub research questions lead to answering the main research question. It is concluded that Value Stream Mapping can offer a useful guidance in the quest of SMEs to become more productive and to be more responsive to customer demand.GENERALIZABILITY The highest level finding of this thesis can be generalized to other production SMEs; VSM can support a company in becoming more productive and more responsive to customer demand. However, the found improvement potential in terms of for instance reduction in delivery time and increase in productivity, should be regarded as specific to the case company. Similar results might not be attainable for other SMEs aiming to becoming lean. Conversely, other SMEs should possibly reach for even higher performance improvements. The results achieved in this research could serve as a benchmark for other SMEs producing tennis balls, which have low volume demand and where manual labour is prominent. ACADEMIC RELEVANCE The contribution of this research to the academic literature is threefold. First, a connection is made between critical success factors of lean implementation methods to understand what method is most appropriate. This should add to the debate about how to start with lean thinking in organizations in general and specifically in SMEs. Then, the VSM technique was performed in combination with the Process Activity Mapping tool. The results shown in this thesis show the potential improvements found by this combinations of tools. This is especially relevant for future research on SMEs which depend strongly on manual activities while having low demand. Finally, this thesis adds a case study of implementing lean in SMEs. Examples in the academic literature of such case studies are lacking to fully grasp the potential for lean in SMEs.MANAGERIAL IMPLICATIONS This thesis shows the potentially substantial improvements which can be revealed by applying the VSM method. The proposed changes can strengthen a company’s competitive position, while requiring limited investment. The thesis shows that direct observation of the production process can expose additional potential for improvement. Managers of SMEs should investigate if lean thinking can be applied to their organization. They should not feel intimidated by the association of lean thinking with large production facilities. LIMITATIONS AND FUTURE RESEARCH This final section will describe the limitations of the research and the results presented in this thesis. Furthermore, suggestions for future research will be presented. LIMITATIONS There are various limitations to this research. The cause of various limitations is the selected research strategy, being a combination of an extensive literature review with a case study of a single company. This limits the generalizability of the conclusions of this research to other SMEs, especially those which differ substantially from Nivia Sports. Furthermore, the research tests only one implementation methods and it is therefore not able to compare the results to lean implementation efforts in similar organization using different implementation methods. Research which covers multiple implementation methods in a wide array of SMEs can offer more deeply insight in the applicability and potential of lean in SMEs, and the effects of following different implementation approaches. The data supporting this research was gathered by direct observation of the production process. This can limit the validity of the results, even after careful consideration of which employee to observe. The translation of the observed data to a generic process can also disturb the process information. Finally, the revealed improvement potential is, for now, hypothetical. Some first implementation steps were made by the case company as a result of this research. Measurements of the improved process should validate the improvement potential. However, the implementation had not reached a significantly progressed state during the period available to this research. FUTURE RESEARCH This research also leads to suggestions for further research. The first suggestion is to increase researching the effects of lean thinking in SMEs. SMEs are an important element of Asian economies and increasing their productivity would enhance the competitive position of the Asian economies in the globalized market. A part of this research should be dedicated to developing stronger understanding of an optimal implementation method. Research should therefore compare instances of lean implementation using different implementation methods to understand advantages of disadvantages or different approaches. To support this research, a framework should be developed which allows to rank the ‘leanness’ of the initial state of each case. This allows for better benchmarking between cases. Also, more research should be done on how to sustain the use of lean methods and how to translate this into lasting competitive advantage. A generic method to calculate the financial implications of a lean effort could help to increase the prevalence of lean implementation.Other areas of research which currently remain relatively untapped are how lean thinking can be implemented in SMEs offering services. Especially lean in micro service enterprises, having less than ten employees, have been left out of scope of the academic literature. Furthermore, more insight should be gained in how implementing lean thinking affects employee well-being and satisfaction in SMEs. The employee dynamics in a small organization might differ from the dynamics in large organization. To ensure long lasting benefits from lean implementation, employee satisfaction should be understood and managed carefully. Finally, in conversations with different companies, it became clear that there is a lack of understanding what improvement philosophy, for instance lean, TOC, or Six-Sigma, is most appropriate for the most pressing issues of a company. 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