DESIGNING LEAN SCHEDULING IN THE SEMI-PROCESS INDUSTRY

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DESIGNING

LEAN SCHEDULING

IN THE SEMI-PROCESS

INDUSTRY

LEAN SCHEDULING AT COMPANY X

Frits Kruise

University of Groningen

Faculty of Economics and Business

Master Thesis

Technology Management

November 2009

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Title: Designing Lean Scheduling in the Semi-Process Industry – Lean Scheduling at Company X

Month and Year: November 2009

Number Master Thesis:

Summary: Goal is to improve the delivery performance. Several process disturbing conditions exist. Concepts are considered to solve issues regarding production control, urgent orders and scheduling. A decision model and a Gantt chart are designed to improve scheduling.

Keywords: Delivery performance, scheduling, Lean.

Student: Frits Kruise

Study: Technology Management

Specialization: Discrete Technology and Process Technology

Student Number: 1535536

Adress: Hoofdweg 26, 9697 NK Blijham

Telephone: 0031 (0)597562222

0031 (0)611928335

E-mail: s1535536@student.rug.nl

University, Faculty: University of Groningen, Faculty of Economics and Business First Supervisor: Dr. Ir. I. ten Have, MBA

Telephone: 0031 (0)503638428

Second Supervisor: Drs. A.J.J. Braaksma

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Preface

In front of you lies the thesis that is written for the final project of my master study Technology Management at the faculty of Economics and Business at the University of Groningen, under the wings of the Lean Operations Research Center, directed by Prof. Dr. Ir. J. Slomp. The thesis is the result of seven months of reading, observing, thinking and writing about scheduling, Lean production and the semi-process industry. The aim of the project was to develop a design to optimize the production scheduling at Company X, a company that produces ink for the packaging industry, in order to achieve a better delivery performance, thereby optimizing utilization of production capacity and maintaining process flexibility at the milling unit and making the processes within the company more transparent, orderly and calm. The design should realize a part of the large improvement of the delivery performance that the management team has in mind.

I would like to thank Ingrid ten Have and Jan Braaksma, my first respectively second supervisor of the University of Groningen, for their assistance, feedback, and suggestions during the research, which pushed me to be critical towards my results and writing. Furthermore, I would like to thank Prof. Dr. Ir. J. Slomp and the LO-RC for the opportunity to develop myself continuously in the field of Lean production, before and during the research. I would like to say special thanks to the people at Company X, who have always supported me during the period that I executed my research at the plant. The discussions I have had with them were very interesting, informative and educational and have given me valuable baggage for the rest of my life. Finally, I would like to thank the people that stand the closest to me, have been there for me and give me their absolute support always; in the past, now and in the future. Thank you for everything!

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Management summary

Company X is a semi-process industry company that produces a broad range of ink for the packaging industry. The semi-process character of the company implies many variables that have to be taken into account when executing production. Several variables are very versatile, e.g., cycle times and output quality. Because of that, production was insecure, scheduling had to cope with many variables that could differ from expected outcomes (e.g., cycle time) and production did not always produce orders on time and in full. The delivery performance at Main Organization X, indicated by the OTIF (On Time, In Full) rate, was below target and therefore not high enough according to the management team. The OTIF rate deteriorated after the takeover of production from the other water based facility of Main Organization X in Europe; this deterioration conflicts with the strategy of Main Organization X. Therefore, the management team of Company X aims at increasing the OTIF rate to a steady percentage near the optimal OTIF rate.

The goal of the research was to optimize production scheduling concerning the bead mills, the regulating tanks and related areas in order to achieve an improvement in the OTIF rate. Production capacity and process flexibility should be utilized to a large extent. Moreover, processes within the company should be more transparent, orderly and calm. The problem exploration showed that multiple issues related to the OTIF rate and scheduling exist in the complex current situation. The most important problems (i.e., the problems that have a large, direct or indirect, negative impact on the delivery performance as appears from observations) can be covered by three problem descriptions:

− scheduling; scheduling does not optimize the allocation of resources to batches and orders due to the lack of appropriate scheduling tools;

− production control; the right up-to-date information is lacking at scheduling;

− complexity of demand; demand is complex and urgent orders can hardly be delivered both on time and in full due to the production system and scheduling.

A consideration of concepts out of the literature led to the choice for several Lean concepts that should help to overcome the problematic situations. A design is drafted for scheduling, specifically for Company X, also taking changes due to managerial decisions regarding the operations, lay-out and organization into account. These changes were already executed or would be executed in the near future.

A decision model and chart are proposed to optimize scheduling, which is the allocation of resources to batches and orders, focusing on the bead mills, regulating tanks and related areas. Subsequently, a

tool package, including the decision model and Gantt chart, is designed for Company X specifically.

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Scheduling needs up-to-date information. Moreover, urgent orders occur regularly and can disrupt scheduling. Because of the significant influence that production control and the complexity of demand have on scheduling, possible improvements for both areas are discussed briefly. These possible improvements can be used in the future to optimize scheduling and the OTIF rate further.

Production control, worked out as the visualization and ordering of information related to

production, such as the production status, is very important because it secures that the processes within the company are transparent, orderly and calm. The scheduler is provided with up-to-date information and has the possibility to allocate resources optimally to batches and orders and to place the batches and orders optimally in the schedule. The time that the scheduler searched for information is eliminated and the scheduler can react more quickly on events, thereby reducing the throughput time of batches and lead time of orders and increasing the delivery performance and the OTIF rate. Using

screens is one of the possible options to visualize and order the information; however, the costs of the

screens can be a problem with regard to the pay-back period of their possible implementation.

A hybrid production system, which is a combination of a make-to-order (MTO) and a make-to-stock

(MTS) production environment, should be used to deal with the complexity of demand. The main

stream of orders should be produced on the basis of customer orders (MTO); the urgent orders should be picked out of the supermarket, after which the supermarket is refilled by production (MTS). The supermarket has to be placed between the operations pumping and dispatch. The supermarket should contain ink in the right packaging and quantities that are often part of an urgent order and are ordered in small quantities seldom in particular; inks that are ordered in large quantities regularly can also be stored in the supermarket. A more detailed analysis of the order stream should help to draft the contents of the supermarket. The supermarket relieves production and scheduling and because of that it makes production and scheduling more flexible. Moreover, the delivery performance and the OTIF rate will be improved because the inks are ready to be picked for orders that belong to the mentioned categories, urgent orders in particular. Kanban cards can be used to visualize the pull signal, which is the information flow informing scheduling about the inventory status of the supermarket when the supermarket should be refilled, in a clear and orderly way.

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Explanatory word list and definitions

Assignment A manual that is sent to the production floor and describes how the operator

has to make the ink (recipe), in which quantity (batch size) and for which orders (customer or customers). One batch has always one assignment. Assignments are used in pre-mix, milling, production planning and quality control and have a code with 8 characters.

Base ink The range of ink that consists of several types of ink and has a recipe that

complies with the requirements of a large number of customers and are ordered by multiple customers. The inks are sold pure to the customer or are combined and blended according to the requirements of the customer. Base ink is also called bulk ink because of the larger produced volume in comparison with the specials/specialized products.

Batch A specified quantity (in kilograms) of one type of ink which is processed or

produced by a machine. A batch can consist of parts of several orders. The term batch is used in production planning, pre-mix, milling, pumping and quality control. Most of the time, it has a code with 8 characters.

Communication The quality and transfer of information between two or a number of elements.

Dispatch The part of production that makes end products ready for delivery to the

customer.

Due date The date on which an order should stand at dispatch, ready to be shipped.

End product A specific type of ink in a specific quantity (as demanded by the customer).

Several end products of the same type of ink and packaging of one customer form an order line. The range of end products equals the total of base inks and specialized products delivered to the customer. Customization occurs by difference in composition of ink, packaging and quantities. An end product is also mentioned simply as product.

Intermediate A specified quantity (in kilograms) of one type of ink that exists in production,

is not ready (i.e., still has to be processed) and is not filled in packaging. An intermediate can exist between operations or can be stored temporarily (several hours) in the production hall and has a code with 8 characters.

Inventory The storage of intermediates or ink in packaging with the intention to store

them for a period of one day or longer.

Lead time of an The time between the moment an assignment is sent to the production floor by

order scheduling and the moment that the product/order stands ready at dispatch to

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al., 1995). Lead time consists of five elements: waiting time, moving time, queuing time, machine set-up times and running time (Cheng, et al., 1996).

MTO Make-to-order. Production based on customer orders (Soman, et al., 2004). A MTO system is often used to produce a high variety of customer specific products. The production planning focus is on order execution and the performance measures are order focused.

MTS Make-to-stock. Production based on the refilling of stock (Soman, et al., 2004). A MTS system is often used to produce a low variety of producer specified products. The focus is on anticipating the demand (forecasting) and planning to meet the demand.

Operation A set of activities that is executed on the item that is processed. Three types of

activities exist (Koning, et al., 2006): value-added (VA), non-value-added (NVA) and necessary added activities (NNVA). All the non-value-added and necessary non-value-non-value-added activities are initially indicated as NVA (Bell, 2006). An operation often can be indicated as a geographical well-defined place in production.

Operators All the people that execute (a set of) activities in one or more production steps

at the plant of Company X.

Order The demand of the customer that a customer puts at the sales department. An

order can exist of multiple products/multiple order lines. If intermediates/end products are in stock and an order is placed that asks for it (pure and/or combined and mixed), they are filled in the right packaging in the right quantity (if necessary). If intermediates/end products are not in stock, they have to be produced (and, if necessary, combined and mixed). The end product is filled in the packaging in the right quantity immediately. Orders exist within sales, production planning, pumping, combining, filling and mixing, dispatch and quality control. An order has a code with 12 characters.

Order line An order line is one type of ink in a specific type of packaging that is part of

an order (e.g., one ink filled in several drums of one type).

OTIF rate On Time, In Full rate. The OTIF rate is a measure for the delivery

performance. It indicates the number of orders that are delivered on time and completely to the customer. If an order line is not ready at the moment it should be (due date), the whole concerning order is indicated as late and as an OTIF error. Therefore, the OTIF rate represents the worst-case situation of the delivery performance of a certain moment. An OTIF error is where an order line is not 1) delivered in full within the delivery time agreed with the customer and/or 2) is not ready in full for the customer to be collected or shipped on the date agreed. The OTIF rate (for a period of one month) is calculated as follows:

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Planning The process of creating a mid-term (approximately three weeks) planning, i.e.,

when orders have to be produced. It also indicates the physical planning, i.e., the planner/production manager.

QC Quality Control. Executes tests with regard to the viscosity, brilliancy, opacity, pH, color intensity and foam of the inks.

Rescheduling Updating an existing production schedule in response to disruptions or other

changes (Vieira, et al., 2003).

Resources The matters that are used to process the materials and produce an intermediate

or an end product. Machines, labor, tools/devices, time and money are resources.

Scheduling The process of creating a short-term (approximately two or three days)

production schedule for a given set of assignments and resources (Vieira, et al., 2003). More specifically, it is the allocation of limited resources to assignments/batches/orders over time (Kazel, 2006), optimizing one or more objectives (Chen, et al., 2008). It also indicates the physical scheduling, i.e., the schedulers.

Specialized products The products that are combined and blended according to the requirements of

the customer. Specialized products are customized products that are normally ordered by one customer. Specialized products are also called specials.

Throughput time The time a product takes to be produced/to flow through the whole production

of a product process (Hopp, et al., 2000); the production time of the sequence pre-mix,

milling, pumping and dispatch. The time that sales (and the reception) spent on the transformation of an order into an assignment using SAP is therefore not included in the times. The times start after an assignment is sent to the production floor. Therefore, the time that an assignment lies at scheduling is not taken into account.

Work-in-Process All the ink (in resources or in packaging) that is being processed by

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List of Appendices

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1 Introduction

This thesis is part of the final project of my master study at the faculty of Economics and Business at the University of Groningen. The aim of the project was to develop a design to optimize production scheduling at Company X, concerning the bead mills, the regulating tanks and related areas, in order to achieve a better delivery performance.

The research and the thesis provide a recommendation for the company, with at least one concrete proposal for production scheduling of the milling unit and the related production units. The result of the research should be delivered in written form as a master thesis, in English. The research and its results are presented during a presentation at Company X and a colloquium at the University of Groningen. The research and the thesis are defended during an oral defense, in the presence of the supervisors from the University of Groningen.

Lean manufacturing serves as an underlying principle, e.g., for the problem analysis, proposed concepts and the design. Lean manufacturing strives for minimization and elimination of wastes (LeanEnt, 2008; McBride, 2003; Likert, 2004). Furthermore, the case study research model of Stuart, et al. (2002) is used to structure the way of working and the thesis.

Firstly, information about Main Organization X and Company X will be given. Subsequently, the research design will discuss, among other things, the problem statement, problem analysis and research questions. The conceptual model shows the variables that influence the delivery performance and have to be taken into account in the research. The methodology shows which literature is used to structure the thesis and analyze the case. The consideration of concepts discusses the concepts out of the literature that are considered and used to solve the issues that are found. The application of these concepts on the case of Company X should lead to a design that optimizes scheduling and improves the delivery performance. A possible implementation of the design is also discussed. The thesis ends with conclusions, limitations of the research, a validation of the research and recommendations for further research.

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2 About the company

Firstly, this chapter gives a brief description of the company, with the main characteristics of Main Organization X that also apply to the plant of Company X. Secondly, the more specific characteristics of Company X will be discussed.

2.1 Main Organization X

The plant of Company X comes under the organization Main Organization X. 2.1.1 General information

Main Organization X is an ink producing company that has over 140 facilities in North, Central and South America, the Middle East, Africa, Australia, New Zealand, India, the Pacific Rim and Europe (Appendix 1). The number of employees worldwide totals 7800 (Main Organization X, 2008). The organization has a worldwide network of partners and distributors and maintains relations with both smaller customers and large multinationals. Company management and private equity funds directed by an investment agency that is based in the United States, Europe, Latin America, Asia and India/Pacific privately own the organization. With revenues of € 2.4 billion in 2008, Main Organization X is one of the two largest suppliers in each region it serves. The company is world leader in providing products for the commercial graphic arts industry.

The history of Main Organization X and Company X is shown in Appendix 2. 2.1.2 Mission, vision and strategy

The mission appears implicitly from the roof of the mission statement of Main Organization X (Figure 1); the vision is reflected by the pillars. The strategy as formulated by Main Organization X results from the mission:

− Our customers are in the center of attention in everything we do; − Everyone of us contributes to our success;

− No harm is done to integrity;

− Continuous improvement raises the returns and contributes to the realization of excellence; − Leadership and teamwork are absolute conditions to realize our objectives.

FIGURE 1 MISSION STATEMENT

2.1.3 Objectives

Performance objectives (Slack, et al., 2008) show on the operational level how an organization is reaching its vision, mission and strategy and can be used to analyze the operations of an organization. Moreover, performance objectives can indicate possible wastes. The objectives can be derived from the mission statement (Figure 1). The five performance objectives or key performance indicators (KPIs; Wikipedia, 2009) quality, speed, dependability, flexibility and cost are discussed by Slack, et al. (2008). The five performance objectives have an operations management character (Slack, et al., 2008). Because the research deals with management issues about the efficient and (effective production of goods (in this case: ink), these performance objectives are highly relevant for this research. The plant manager also mentioned some important production oriented spearheads in addition to the spearheads that appear from the mission statement (Table 1).

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TABLE 1 PERFORMANCE OBJECTIVES

Main Organization X has the slogan “Rely on us”, which indicates that reliability and dependability are important objectives for Main Organization X. The OTIF (On Time, In Full) rate, the measure that indicates the delivery performance, is related to the dependability (Table 1).

2.2 Company X

The establishment of Company X (Appendix 3) comes under the Packaging Ink division of Main Organization X (Appendix 2). Approximately 75 employees work at the establishment of Company X; 35 employees work in production and quality control (QC), 25 in the laboratory and as technical services and the rest in the office or as management.

2.2.1 Products

The plant of Company X produces (mainly) water based ink, which is produced for and used in the packaging industry. The used range of inks (Appendix 4) consists of series of high concentrated and monopigmented base colors, which can be complemented by adding additives or varnish. Moreover, the base colors can be combined and blended to produce a special ink according to customer specifications. Combining the inks gives Main Organization X the possibility to produce a large range of water based inks, which are applicable in a very diverse range of products and processes (Main Organization X, 2007). Products differ because of their application by the customer. The packaging industry uses the ink to print paper or cardboard of, e.g., corrugated cardboard, bags, envelopes, cigarette packaging, hygiene products (e.g., diapers and sanitary towels), stickers, gift-wrappings, wrappers (MacDonald’s) and coffee cups that all serve as packaging. Besides, it produces ink for other applications such as latex and skins of sausages. Thus, the production site is a multi-product plant. Company X produces two main series, Main Series A and Main Series B. Ink differs within one series on the basis of the type of pigment, additives and varnish that is used within the range of products. The difference between the main series of Company X is initially made in the ability to be (re)dissolvable (Appendix 4). The facility of Company X is a water based plant and produces mainly Main Series A; this is also shown in the diagram that mentions the percentages of the total volume of ink produced by Company X (Appendix 4). Besides the main series, Company X also produces other products in relative smaller quantities. Company X has recipes of 148 types of ink; 49 types of ink are part of one of the main series that is focused on in this research, i.e., Main Series A.

Company X objectives Performance objectives Elements

Become the best Quality

Customers Quality, Dependability, Flexibility Customer-oriented, Integrity

Shareholders Cost

Employees Quality Safety, Health, Working Environment

Exceptional value Quality

Consistent Quality Quality

Continuous innovation Quality

Company X objectives Performance objectives Elements

Right first time Quality

On time and in full dispatching (OTIF) Dependability Responsiveness, Reliability, Responsibility

Tons shipped Speed (Flexibility, Cost)

Able to adapt to changes and unforeseen situations Flexibility, Speed

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The ink production process of Company X can be specified as a MTO production environment because production is based on customer orders (Donk, 2001; Donk, et al., 2005). Production exists of six operations (Figure 2) and operates normally between 5:45 A.M. and 9:45 P.M. in two shifts (5:45 A.M.-2:00 P.M. and 1:30 P.M.-9:45 P.M.). Operators have a low to medium level of education.

FIGURE 2 CURRENT STATE: PRODUCTION PROCESS

The warehouse is the place where the raw materials are stored; packaging is stored in an annex. The operations that process ink are:

1) Pre-mix: the pigment particles are enclosed by water and varnish particles using dissolvers (Appendix 5). The dissolvers of pre-mix do not dissolve the pigments; the pigments that are used by Company X are insoluble;

2) Milling: the output of pre-mix is transferred to milling by pipelines (large batches, maximally 4 tons) or tubs (small batches, maximally 1 ton) and subsequently ground by the bead mills (Appendix 5); the bead mills crush the pigment parts of the base concentrate to small(er) parts until the concentrate has the right characteristics. The milling unit consists of several bead mills and regulating tanks. The regulating tanks are also used to fine-tune the ink composition. The bead mills and regulating tanks together form circuits in which the ink flows one or multiple times, dependent on the type of pigment. The number of times that a batch has to flow through a bead mill is specified by the recipe (black ink has to flow only once, other colors multiple times). Bead mills can work unmanned, so they can also work at weekends. Bead mill capacity varies in residence time, which is determined by the size of the head of a bead mill. QC executes several tests to check the characteristics of the ink. If the characteristics are not right yet, the ink has to be adjusted (e.g., the ink has to flow again through the bead mills and regulating tanks or raw materials such as varnish or water have to be added to the ink to get the desirable characteristics) or, in the worst case, the batch is rejected;

3) Pumping: the base is pumped from the regulating tanks in the demanded packaging in the right quantity and transferred to the dispatching area or pumped to storage tanks or in packaging for storage;

4) Combining: different substances are put together manually and/or using two filling machines that are connected to several storage tanks and require orders by hand. The combination of substances will form an ink that fulfills the wishes and requirements of the customer;

5) Mixing and filling: if necessary, some materials are added to the output of the combining stage, which then is mixed to make a mixture that has the right characteristics. QC checks these characteristics by several tests. As well as is the case with the tests at milling, QC can adjust a batch. QC can also reject a batch, which implies that a whole new batch of ink has to be produced. The end product is put in the preferred packaging in the right quantity;

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The production floor is situated in a production hall, which is divided into three smaller halls: 1) warehouse, 2) pre-mix and 3) milling, pumping, combining, mixing and filling, and dispatch

(Appendix 3). The driving path through the production hall follows the flow of materials through the factory. The warehouse has an opening (also for fork-lift trucks) to the annexes. The dispatching area has an opening where fork-lift trucks can go in and out to load trucks. Offices and other rooms (where laboratories and conference rooms are situated) are fixed to the production hall. Company X also has a few annexes on its plant. The annexes house a water purification unit, technical services, a charge point for fork-lift trucks, a cleaning room for packaging and a storage point for poisonous and/or flammable substances.

2.2.3 Customer demand

The customer demand consists of a main, consistent stream of order (orders that are put regularly at sales) and a turbulent stream of orders (that consists of unexpectedly posited orders and urgent orders). The ordered and produced quantity of one month is approximately 200 tons ink on average, the number of produced batches totals more than 300 per month and the number of orders totals about 400 per month. Intercompany (ICO)1 orders mainly Main Series A products and orders the largest part of Main Series A orders produced at Company X. The most important customers for Company X are called key-accounts.

2.2.4 Planning and scheduling

Sales is the department that receives customer orders and processes customers orders by putting the right information in the SAP system, an IT tool which comes under the ERP (Enterprise Resource Planning) package. The package of modules at Company X is very comprehensive, but not all-embracing; SAP is implemented at Company X to handle the order fulfillment, manufacturing, inventory, distribution and financial accounting operations (Filipczak, 1997). After the information is imported, the employees at sales mention the required information (e.g., customer, ink and packaging) on paper. These paper customer orders are printed and passed on to scheduling and dispatch.

Planning and scheduling occurs on the basis of orders (customer oriented) and assignments (production oriented). Some customers give some kind of a forecast of what they want to order in the coming weeks. However, the forecast is not a guarantee; it could be possible that they place the orders earlier or that the orders are different from the forecasted orders. After orders have been processed by sales using SAP and the allocation of assignments to machines has been discussed among several people (e.g., scheduler, foreman, laboratory, production manager), assignments are sent to the production floor. The assignments are fixed to the tubs that contain the ink. If ink is transferred by pipelines, the assignments are placed at the operations. A batch can consist of several orders.

2.2.5 Performance

According to the plant manager, the objectives of Table 1 can be given a weight or factor of importance (Table 2). The weights can be translated to a polar representation (Figure 3).

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FIGURE 3 PERFORMANCE OBJECTIVES INDICATOR, A POLAR REPRESENTATION (SLACK, ET AL., 2008) OF THE PERFORMANCE OBJECTIVES OF COMPANY X

Company X wants to reach its goals with as little resources as possible. Generally, there is an inversely proportional relation between the importance of the objective cost on the one hand and the objectives quality, speed, dependability and flexibility on the other hand. Cost is often part of trade-offs with the other performance objectives (Slack, et al., 2008). Therefore, it seems remarkably that cost as well as quality, speed, dependability and flexibility are as important as shown in Table 2 and Figure 3. Probably, there exists some tension in the operations because of this recognition.

Data are sometimes transported manually from SAP to Microsoft Excel 2000 to draft performance sheets, e.g., to show the OTIF rate per period of time.

2.2.6 Future changes

The description of the future changes shows how the current situation will be changed in the near future.

The near future implies that the other water based facility of Main Organization X in Europe will not produce base ink anymore as from April 2009; the largest part of the production of the other water based facility will be moved to Company X step by step. The other water based facility will only produce specialized products and deliver white and varnish to the regional market. The production of the ink that is used to make the specialized products of the other water based facility (i.e., the base ink) will be taken over by the plant of Company X. The takeover means that Company X will be the only mother plant of Main Organization X in Europe that produces water based ink.

The operations pre-mix, milling and pumping will be changed regarding machine composition and lay-out in the future situation because of managerial decisions (Appendix 6):

1) Pre-mix: two dissolvers (one for yellow, one for black ink) will be added to the current lay-out;

2) Milling: Seven bead mills will be added. A row of eight bead mills will be set up which will (initially) produces the bulk/base ink. Couples of bead mills will be formed, which will each produce the color yellow, blue, red or black initially (Appendix 7). The management has dedicated each bead mill to a certain color on the basis of the ink characteristics (e.g., difficulties with milling due to pigment features) and the bead mill characteristics (e.g., maintenance sensitivity); the total cleaning time is reduced, because less colors have to be milled by one bead mill. One bead mill type is less sensitive to maintenance than other types and can therefore process the more “harder” pigments. The other four (new) bead mills will process smaller batches. Moreover, another eight regulating tanks will be put in the milling unit. Every bead mill can always use two regulating tanks; therefore, every color has four regulating tanks available;

Performance objective Weight

Quality 9 Speed 8 Dependability 8 Flexibility 8 Cost 10 Importance of performance objectives

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3) Pumping: the pumping unit will be equipped with four connection points to the regulating tanks. Pumping will not pump substances to storage points of combining anymore, because combining and mixing and filling will disappear out of the large production hall. These units will be placed in the Regional Service Center (RSC), which mixes base ink with each other (and additives) and because of that falls out of the scope of the research initially.

Management has decided to change the flows of ink to the milling unit. The main difference between the future milling loop and the current milling loop (Appendix 5) is that the option will exist to not directly let the ink flow from the dissolver to the bead mill, but firstly store it in the buffer tank that will be placed before the bead mill. This method provides the possibility to already start a batch at pre-mix and store it in the buffer tank at the time that the bead mill is still processing another batch; production becomes more flexible. The buffer tank can prevent the bead mill of having no input. Besides, the buffer tanks can also be filled when the bead mill is still processing a batch; pre-mix can then already produce a new batch. The future milling loop should save 20% of the milling time, which is 3-4 hours compared with the current milling loop. Eight buffer tanks of 5 tons will be installed. The larger amount of ink that has to be produced because of the takeover will be divided in two clear sections: mass production or production of bulk ink (80% of the produced volume in the future situation) and the production of customized production or specialized products (20% of the produced volume in the future situation). The clear separation will be physically clear because a new (small) production hall, the Regional Service Center (RSC), will be built nearby the current production hall. The RSC handles mixing recipes and will be supplied by the large production hall that produces bulk/base ink. The base ink, white and varnish will be produced in the large (current) production hall. The managerial decision to split the production of base ink and specials physically means that the dispatching area will be expanded in the large production hall; combining and filling is moved to the new production hall. A plan of the new lay-out of the large production hall is placed in Appendix 6. The customer demand will be 2-3 times as large as it is now. The increase in volume means that the ordered quantity that has to be produced is approximately 600 tons ink per month. The Main Series A is the series that will (probably) be demanded and produced the most after the takeover. The 80 types of base ink that will be produced by the large production hall can be delivered to other companies or the Regional Service Center (RSC). This important new key-account handles mixing recipes and will be supplied by the large production hall. The composition of the key-accounts will remain approximately the same for the rest. The characteristics of the customer demand will remain the same for the rest; variable products, order composition, packaging and quantities, a fluctuating demand pattern, urgent orders and difference in importance of customers. The number of customers will be larger.

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3 Methodology

The methodology discusses how the thesis and research are structured, the case is analyzed and problems are determined.

Stuart, et al. (2002) suggest that the process of case study research should be broken down in five critical stages (Figure 4). The first stage of the research process involves defining the problem statement, goal, main research question, research questions and scope. The second stage is the development of measurement instruments to capture data for the analysis. The third stage is gathering data via the selected quantitative and/or qualitative methods. The fourth stage involves analyzing the data, to determine what has been learned and how to present it. The last stage is writing the dissertation, what means in this case that the results have to be written down in the form of a thesis.

FIGURE 4 CASE STUDY RESEARCH (STUART, ET AL., 2002)

The Value Stream Mapping (VSM) method (Shingo, 1985) is a visualization tool oriented to the Toyota version of Lean Manufacturing (ValueBasedManagement, 2009). The VSM method maps information and product flows between (production) units or departments (Rother, et al., 2003). VSM helps to understand and streamline work processes using Lean tools and techniques. The five steps of VSM are to:

1) Identify product families and choose a product family; 2) Map the Current State, the situation as it is now (IST);

3) Analyze the current situation and create flow by eliminating waste;

4) Map the Future State, the desirable situation (SOLL), which represents the overall concept the researcher wants to achieve (Liker, et al., 2004);

5) Draft a working plan and implement the Future State.

The implementation of the Future State (or one design) will be discussed but not executed in this research.

Interviewing and observations on the production floor, often called Genchi Genbutsu, which states that one should go and see the actual place and understand the real situation through direct observation (Liker, et al., 2004), are used to develop insight in the current situation and problematic situations, which is done in the second step of VSM. The problems that exist within the demarcated system (De Leeuw, 2002) are detected by the third step of VSM. The problems structured and analyzed using an Ishikawa diagram. The purpose of an Ishikawa diagram (Vanderbilt University, 2007; Sigma Innovations, 2008; SkyMark Corporation, 2009) is to arrive at a few key sources that contribute most significantly to the problem. A problem can have causes in different categories; Machine, Method, Materials, Maintenance, Man and Mother Nature (the six M’s). Instrumental problems have to be converted to functional problems (Prins, 2008). Instrumental problems are problems within the organization; functional problems are the (negative) outcomes (i.e., the symptoms) these problems cause (Figure 5). Instrumental problems cannot be solved; functional problems are generally measurable and can be handled and overcome.

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FIGURE 5 PROBLEM DETERMINATION (PRINS, 2008) System

1. Lead to

2. Are caused by 1. Why is that bad?

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4 Research Design

The research design discusses the boundaries of the research and an analysis of the current situation. Subsequently, the goal, main research question and research questions are formulated and a conceptual model is drafted to give direction to the research.

Different people from different departments and from different (hierarchical) levels in the organization are interrogated; the obtained information serves together with data as the input for the analysis and the rest of the research. Besides, the processes within the organization were observed. First, VSM is used to identify and choose a product family. The product family in this case is the runner, i.e., the Main Series A; this series covers the greatest volume of the total volume produced by Company X (Appendix 4). Secondly, VSM is used to map the processes at Company X and draft the Current State (Appendix 8). The map specifies relations between organizational units. Cycle times, throughput times (Appendix 9) and utilization and reliability percentages are gained by executing an analysis of milling data and observations. Subsequently, the Current State map will be used in this chapter to analyze the Current State, detect the problematic situations and identify waste in the process on the basis of the outcomes of the interviews and observations.

4.1 Prerequisites

Several prerequisites arise from the restrictions of the production process. Moreover, Company X has formulated several prerequisites. The research has to meet the following conditions:

1) The level of effectiveness of production, i.e., the output of the production process at the cost of efforts by, e.g., employees, has to be maintained or increased;

2) The process has to remain flexible, especially with regard to the mix, volume and delivery flexibility;

3) The safety has to be maintained or increased;

4) The company wants a payback period of 0.5 to 1 year with regard to possible investments; 5) Inventory has to be as low as possible;

6) Informal “operator aging policy” is applied in production (because of hard activities or operations). The policy implies that the age of operators has to be taken into consideration when allocating operators to tasks/assignments/batches;

7) If necessary, the lay-out can be changed (e.g., machines can be moved to another place); 8) There is little to no space available for the placement of packaging or other materials. The

available amount of space might be a little bit more in the future situation because of renovation and extension of annexes;

9) Extra SAP (ERP package) modules can be acquired if necessary;

10) Not all the fork-lift trucks are mutually exchangeable due to pole height and maximal headroom under racks and staging;

11) All the operators have a fork-lift truck certificate (not for the lateral fork-lift truck).

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4.2 Assumptions

Some assumptions are made to restrict the area that will be taken into account in the research and to decrease the level of complexity of the research to some extent:

− When the department purchasing has sent a notification to its storage point of packaging and raw materials that the items have to be delivered to Company X, the packaging and raw materials will be delivered on time, in full;

− The right types of packaging are always available in a sufficient quantity at the time a batch should be processed;

− The warehouse stores raw materials always in sufficient quantities, in such a way that raw materials can be delivered to the production process on time;

− Normally, quality control can deliver the test results of an order to the production process within 30 minutes;

− If the large production hall produces on time, in the right quantity, in the right packaging on the basis of assignments and orders, the RSC processes the base ink and finishes the products and orders on time and in full;

− The first OTIF numbers in the period after production takeover of the other water based facility showed that the OTIF rate of Company X dropped significantly. The drop in OTIF rate was partly caused by the earlier takeover of production of the other water based facility than initially was planned. Because of that, capacity, which was planned to be expanded in the second quarter of 2009, was not ready to handle the larger production, which resulted in many overdue orders. The research will assume that the OTIF rate will be on the former level again after a while because the capacity than can handle the quantities that are ordered by customers. The former or initial OTIF rate will therefore be the starting point of the research.

The correctness of these assumptions is not investigated in this research. However, it could be possible that sometimes raw materials and packaging are not available in a sufficient quantity at the time that a batch should be processed. Moreover, quality control sometimes needs more than 30 minutes to execute tests due to the requirements of the customer or the features of the ink.

4.3 Scope

Following on the prerequisites and the assumptions, the scope restricts the investigated system further. The scope describes this system and which elements are included in the research (De Leeuw, 2002). This demarcated system (Table 3) is the set of objects, chosen by the researcher, which are mutually related, in order that no elements are isolated (De Leeuw, 2002).

TABLE 3 DEMARCATION OF THE RESEARCH

In scope (areas of focus)

Moderately in scope (related areas)

Not in scope (not considered at all)

Geography Company X Region/Worldwide

Milling Pre-mix Warehouse

Regulating tanks Pumping Laboratory

Scheduling Dispatch Combining

Quality control Mixing and filling

Planning Order processing before scheduling

Specialized orders/ink White Varnish Raw materials All other series Process

Product Colored base ink (Main

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The research will only investigate the plant of Company X. Furthermore, the production process as it is now (Appendix 3) is taken into account in the problem analysis. The production process as it will look like within the center of the large factory hall (Appendix 6) will be investigated in the remainder of this thesis. The research will focus on the Main Series A; white, varnish and raw materials that are passed on to customers are not taken into account. The research will also not take the order processing by sales into account. Only if it is necessary to explain something about the order processing by sales (e.g., to show how orders flow to scheduling) it will be handled.

4.4 Problem statement

It appears from the interviews and observations that production scheduling has difficulties with process scheduling and variations that are difficult to overcome due to specific, individual material and product characteristics and unexpected chemical reactions. Variety exists at Company X in all the five forms as discussed by Bertrand, et al. (1998), i.e., variety in products (product diversity), customers (variable order composition), operations (variable cycle times), routings and resources. These difficulties result (in the worst case) in longer throughput times of products than planned, overdue orders and non-delivery to the customers of Main Organization X and a decrease of the OTIF rate. This decrease implies that Company X is becoming worse in delivering on time and in full, which is related to the mission and several spearheads, directly (dependability, quality, speed) and indirectly (costs). The high degree of complexity should require a high level of information processing and coordination; scheduling should have all the information it requires to have the possibility to optimally execute its scheduling activities. To indicate the difficult situation in which scheduling has to be executed: almost none of the common simplifying assumptions that are used for classic scheduling, such as the assumptions that no jobs arrive after processing begins, process times are deterministic and machines never break down (Hopp, et al., 2000), are applicable in the case of Company X. Furthermore, the use of (planning and) scheduling tools is very limited and very abstract because it is mainly communicated orally; this abstraction causes troubles and irritations, mainly due to miscommunication.

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production status and bad communication (also because of shortcomings or wrong use of SAP, such as a wrong representation of order status due to a wrong representation of the current inventory level).

4.5 Problem analysis

The problematic situations can all be placed in the Current State map on the places where they occur (Appendix 10). An Ishikawa diagram (Figure 6) is used to analyze the problems and issues. The category Mother Nature is not represented in the Ishikawa diagram, because there were no problematic situations (within the scope of the research) that dealt with this category. The Ishikawa diagram shows all the issues related to the OTIF rate in the case of Main Organization X in a structured way.

The most important issues from the Ishikawa diagram (first level problems) are mentioned in Table 4 as an instrumental or functional problem. Functional problems are made concrete using the definitions of wastes (Cheng, et al., 1996) and lead time (Tersine, et al., 1995), to indicate the relation with regard to the delivery performance. Subsequently, the key sources, the sources of problems that contribute most significantly to the OTIF rate problem, will be detected, holding the objectives of Company X in mind (Subparagraphs 2.1.2 and 2.1.3). The key sources are sorted out by indicating them with red and orange circles and numbers in the Ishikawa diagram and making them red and orange in the table. Orange (important problems that have to be taken into account in the design, but that do not have to be overcome in this research at all costs) and red (problems that have to be solved/overcome in this research) circles mention the problems that are most important for this research. The importance of problems is determined on the basis of the impact of the problem on the customer (external view), because the customer is important for Company X as appears from the mission statement (Subparagraph 2.1.2). Furthermore, problems that have a significant impact on the production process (internal view) could cause problems that have a certain effect on the delivery performance and thus for the customer (Paragraph 4.4).

The number that is attached to the circles indicates the importance of the problem. A low number indicates that a problem has high priority; a high number is a problem with less priority. All the other problems that are not indicated with orange or red are worthwhile mentioning, but are not targets to be solved for this research. Second level problems, problems that lead to first level problems, can help when drafting the design because they are more concrete and show how first level problems can be solved possibly.

Several problems related to the OTIF rate relate to scheduling and wastes of time. These relations imply that an improvement of scheduling causes an improvement in the dependability, quality, speed and flexibility of the production process and in the delivery performance. Therefore, improving scheduling in such a way that it can cope with the new production situation, the objectives of Main Organization X are reached and the mentioned problems are overcome will lead to a higher OTIF rate. The most important problems, i.e., the red indicated problems, which have a large direct, negative impact on the production process and a significant indirect, negative impact on the delivery performance (as appears from observations) can be covered by three problem descriptions:

− scheduling; scheduling does not optimize the allocation of resources to batches and orders due to the lack of appropriate scheduling tools;

− production control; the right up-to-date information is lacking at scheduling;

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TABLE 4 INSTRUMENTAL AND FUNCTIONAL PROBLEMS. BOLD PROBLEMS ARE THE BOLD PROBLEMS (I.E., MAIN PROBLEMS) AS MENTIONED IN THE ISHIKAWA DIAGRAM

4.6 Goal

From the problem statement, the goal for the research can be formulated according to the SMART-goal setting concept (Brock University, 2009):

Optimize production scheduling in order to achieve an improvement in the OTIF rate, thereby optimizing utilization of production capacity, maintaining process flexibility at the bead mills and making the processes within the company clearer, more transparent and more orderly.

Category Instrumental problem Functional problem Concrete consequence for OTIF rate

Poor communication Waste of time due to activities that are not geared smoothly to each other, nonutilized capacity, information and data is not up-to-date

Several unnecessary in-progress hours on each batch (varying per batch), resulting in longer lead time; sometimes not able to deliver urgent orders; finished orders have to be pulled out of each other because of changes in orders; scheduling cannot execute scheduling activities in a optimal way, because of that, orders/order lines become overdue unintentionally and OTIF rate decreases

Remaining problems Not working effectively the full working hours due to motivation problem with employees, remaining wastes due to waste of ideas and creativity of employees

Small waste of time (new charge has to be printed due to loss in mess of charges on production floor) to large waste of transportation (could be external set-up), leading to longer lead times and possibly structurally lower OTIF rate

Overproduction More product than needed: storage space and life problem, waste of transportation and motion

Inability to handle urgent orders adequately

Product not ready on time Late delivery of orders/Back orders (late delivery of certain parts of an order), resulting in lower OTIF rate

Long quality test time Waiting time in production process Several unnecessary in-progress hours on each batch (varying per batch), resulting in longer lead time; sometimes not able to deliver urgent orders, resulting in lower OTIF rate

Output of pre-mix of bad quality

Long(er) milling time Hours of extra milling time (pigments are not embraced by water good enough and this lengthens the milling time), resulting in longer lead times and possibly lower OTIF rate Variable grinding time Rescheduling (short-term) regularly, unsecure

(longer than expected) lead times

Waste of time due to rescheduling (minutes), longer lead time (hours), which can lead to lower OTIF rate Breakdowns, resources not

available, illness, scheduling not optimal

Idle time Minutes (machine ready processing) to hours

(breakdowns, illness, no input from preceeding step), which can result in multiple overdue orders and a significantly lower OTIF rate

Abnormal cycle times Longer lead time than expected Lead time minutes (rescheduling) to hours (longer processing time) longer, resulting in possibly lower OTIF rate

Not fully utilizing capabilities of work force

Not working effectively the full working hours due to motivation problem with employees, remaining wastes due to waste of ideas and creativity of employees

Loss in production time due to unutilized capacity and activities that are not smoothly geared to each other, leading to longer lead times and possibly structurally lower OTIF rate

Uncareful behaviour Accidents, bad quality of ink and rejected batch Loss of production hours, could easily total more than 24 production hours, resulting in possibly overdue order and lower OTIF rate

Lack of knowledge Longer lead time, bad quality of ink and rejected batch

Loss of production hours, could easily total more than 24 production hours, resulting in possibly overdue order and lower OTIF rate

Little time for reparations Long(er) break downs Equipment breakdown Idle time

Lack of storage possibilities leads to finished orders to be moved (minutes). This time could be used for activities that add value or are more necessary

Maintenance Methods

Waiting time Rejected batches

Waste of transportation and motion

Material

Machines

Queuing time, storage (life) problem

Men

Lack of leadship skills with foremen

Not optimal affection with the total result

Many movements of raw materials/end product

Bad quality of raw materials

Raw materials/packaging not available

Longer lead time (hours), which can result in multiple overdue orders and a significantly lower OTIF rate Nonvalue adding time due to activities that are not

geared to each other, nonutilized capacity

Available production hours not optimally used, not producing (an hour a day beside the normal breaks etc.), leading to longer lead times and possibly structurally lower OTIF rate

Long inventory time between machines

Often several days, resulting in longer lead time and possibly lower OTIF rate

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The research takes place from the 9th of March 2009 until the end of August 2009. The goal has to be reached by that time. Management aims at increasing the OTIF rate to an almost optimal OTIF rate, which has to stay on a steady level. At least one design has to be drafted and worked out in detail.

4.7 Main research question

The formulated problem statement and goal lead to the following main research question:

How can the production scheduling concerning the bead mills, the regulating tanks and related areas be optimized in order to achieve an improvement in the OTIF rate?

Production capacity and process flexibility should be utilized to a large extent (Paragraph 4.6). Processes within the company should be more transparent, orderly and calm.

4.8 Research questions

The next research questions (RQs) can be formulated on the basis of the main research question: 1) How should scheduling concerning the bead mills, the regulating tanks and related areas be

designed to optimize the allocation of resources to batches and orders in order to produce batches and orders on time and in full?

2) How should production control be designed to deliver the right information up-to-date to scheduling?

3) How can scheduling deal with the complexity of demand?

RQ1 discusses the issue of the allocation of resources to batches and orders, which is not optimal. RQ2 deals with the status about production characteristics that has to be transferred to scheduling. RQ3 discusses the issues regarding the complexity of demand, especially the issue concerning (not delivering) urgent orders.

4.9 Conceptual model

Following on the problem analysis (Paragraph 4.5) and the research questions (Paragraph 4.8), a conceptual model is drawn up (Figure 7) to serve as a basis for the choice of research methods for the researcher (Slomp, et al., 2006). Moreover, it shows which variables influence the delivery performance and are included in the research. It also serves as a framework to interpret and communicate the results with regard to the reader. Arrows between variables indicate a causal relation. The direction of the arrows mentions which variable influences which variable(s). The dotted line indicates the variables of the conceptual model that are the most important for this research. The white blocks indicate the research questions that discuss the causal relations in the model.

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FIGURE 7 CONCEPTUAL MODEL

4.9.1 Explanation of definitions of the variables

Subsequently, the variables of the conceptual model, which originate from observations (Chapter 2 and 4) and literature, will be discussed one by one. The explanation of definitions of the variables will be given to explain what is meant by the variables in the research. Definitions of variables that are part of the main variables delivery performance, production control, complexity of demand and scheduling are mentioned in the explanatory word list and definitions at the beginning of the thesis if necessary. The delivery performance is the degree to which Main Organization X comes up to its goals and objectives concerning the delivery of products to customers. The delivery performance can be measured by the OTIF rate (Gunasekaran, et al., 2004), which consists of two parts: delivery on time and in full. The OTIF rate indicates the delivery reliability and order completeness, i.e., the number of orders that is delivered at the customer both on time and completely. On time delivery is mainly influenced by the lead time (Tersine, et al., 1995) and the speed of the production process (Gunasekaran, et al., 2004); on time delivery relates mostly to RQ1 and RQ3 (Figure 8). In full delivery is mainly influenced by the tuning of production of order lines on each other; in full delivery is mainly related to RQ1 and RQ2.

FIGURE 8 OTIF: ON TIME AND IN FULL

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− Up-to-date information (Stankovic, 1996; Zentner, et al., 1994): • Production status (Akkerman, 2007);

• Inventory and Work-in-Process (Akkerman, 2007; Blömer, et al., 1998; Loos, et al., 1997);

• Unexpected situations (Akkerman, 2007; Blömer, et al., 1998; Loos, et al., 1997; Orçun, et al., 1997);

The complexity of demand relates to the variation in the characteristics of the incoming orders: − Occurrence of urgent orders (Akkerman, 2007; Gunasekaran, et al., 2004);

− Variation in the demand pattern (Gunasekaran, et al., 2004); − Order diversity (Akkerman, 2007; Gunasekaran, et al., 2004);

− Product diversity (Akkerman, 2007; Blömer, et al., 1998; Gunasekaran, et al., 2004; Ivănescu, 2004; Orçun, et al., 1997);

Scheduling is the management of the production process. Scheduling creates short-term (approximately two or three days) production schedules that deal with the allocation of limited resources to assignments/batches/orders over time (Vieira, et al., 2003; Kazel, 2006):

− Production routings (Blömer, et al., 1998; Ivănescu, 2004; Loos, et al., 1997); − Resources:

• Reliability (Akkerman, 2007);

• Utilization (Akkerman, 2007; Gunasekaran, et al., 2004); − Resource allocation:

• Cycle times (Blömer, et al., 1998; Ivănescu, 2004; Loos, et al., 1997; Zentner, et al., 1994);

• Capacity (Akkerman, 2007; Blömer, et al., 1998; Ivănescu, 2004; Loos, et al., 1997; Zentner, et al., 1994);

• Batch size (Akkerman, 2007; Zentner, et al., 1994)

• Recipes (Akkerman, 2007; Blömer, et al., 1998; Orçun, et al., 1997);

• Changeovers/Set-ups (Akkerman, 2007; Blömer, et al., 1998; Loos, et al., 1997); • Shared resources (Akkerman, 2007; Blömer, et al., 1998; Ivănescu, 2004; Loos, et al.,

1997; Zentner, et al., 1994);

− Resource allocation tools (Akkerman, 2007; Gunasekaran, et al., 2004; Loos, et al., 1997; Zentner, et al., 1994);

− Lead time of an order (Akkerman, 2007; Gunasekaran, et al., 2004; Hopp, et al., 2000; Ivănescu, 2004; Loos, et al., 1997; Tersine, et al., 1995);

− Throughput time of a product (Hopp, et al., 2000; Ivănescu, 2004).

If necessary or preferable, links will be made between scheduling and planning. The research, however, concentrates on scheduling (Paragraph 4.3).

4.9.2 Relation between variables and performance objectives

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Dependability: executing activities on time and completely for customers to deliver their goods exactly when they are needed (Slack, et al., 2008), resulting in a high OTIF rate. Dependability is the most important performance objective in this research, also considering the mission of Company X (Subparagraph 2.1.3). If the customer can be sure that the order will be delivered on time, in full, the customer can rely on Company X, the dependability will be high, resulting in a high OTIF rate. Dependability saves money, because a high dependability and reliability decreases the negative consequences in terms of money for the customer of not fulfilling the customer’s expectations (e.g., overdue delivery) by the producer. The possible amount of claims (Gunasekaran, et al., 2004) as a result from these negative consequences is also decreased. Quality has a positive impact on dependability; a lack of quality affects the dependability in a negative way, because an unstable production process could mean that cycle times are unexpectedly longer, orders become overdue and the OTIF rate decreases.

Speed: the faster customers can have the product and/or (complementary) service, the more likely they are to buy it, the more they are willing to pay (more) for it and/or the greater the benefit they receive (Slack, et al., 2008). If production has short lead times and can produce orders quickly enough to comply with due dates, the OTIF rate is high. Speed also deals with the speed of information transfer. Quality: consistent conformance to customers’ expectations (Slack, et al., 2008). Quality inside the operation refers to the number of mistakes and faults and the proportional amount of cost, which can be expressed as cost savings or wastes (Gunasekaran, et al., 2004). Quality can therefore also be seen as the amount of waste that exists in the processes. Wastes extend the lead time, which can cause multiple order lines to become overdue. Moreover, the delivery and on-time performance and the OTIF rate could be decreased (Suri, et al., 2003; Tersine, et al., 1995). A decreased OTIF rate could mean that customers have complaints (Gunasekaran, et al., 2004) because the customers rely on a consistent quality from the producer and complain if orders are not delivered on time and/or in full (Slack, et al., 2008).

DESIGNING LEAN SCHEDULING IN THE SEMI-PROCESS INDUSTRY

DESIGNING

LEAN SCHEDULING

IN THE SEMI-PROCESS

INDUSTRY

LEAN SCHEDULING AT COMPANY X

Frits Kruise

University of Groningen

Faculty of Economics and Business

Master Thesis

Technology Management

November 2009

Preface

Management summary

Explanatory word list and definitions

Table of Contents

List of Appendices

1

Introduction

2

About the company

2.1

Main Organization X

2.2

Company X

3

Methodology

4

Research Design

4.1

Prerequisites

4.2

Assumptions

4.3

Scope

4.4

Problem statement

4.5

Problem analysis

4.6

Goal

4.7

Main research question

4.8

Research questions

4.9

Conceptual model