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    YAAR UNIVERSITY

    FACULTY OF ENGINEERING

    DEPARTMENT OF INDUSTRIAL ENGINEERING

    GRADUATION PROJECT

    PINAR SU PRODUCTION GROUP

    PROJECT by

    HALIL CANER KARAOGLU

    DOGUKAN ANIL YILDIZ

    CENGIZHAN AYDIN

    PROJECT SUPERVISORS

    OMER OZTURKOGLU

    ADALET ONER

    ZMR, 2014

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    i

    Table of Contents

    1. INTRODUCTION .................................................................................................................................. 1

    2. GENERAL INFORMATION ABOUT PINAR SU .................... ..................... ..................... ......... 1

    3. MICRO SYSTEMS OF PINAR SU ................... ..................... ..................... ..................... ................ 4

    3.1.1. Water of Display Parameters ..........................Error! Bookmark not defined.

    3.1.2. Layout of Facility ............................................................................................. 6

    3.1.3. Processes in Production Lines .......................................................................... 7

    4. OBSERVATIONS AND SYMPTOMS .................. ..................... ..................... ..................... ................ 9

    4.1. Analysis of Production Processes ............................................................................................ 9

    4.2. SYMPTOMS ................................................................................................................................ 104.2.1. Analysis of Downtimes in Production Line 1 and Line 2 .............................. 12

    5. PROBLEM DEFINITION, TARGET & CRITICAL SUCCESS FACTORS.................. 13

    5.1. TARGET & CRITICAL SUCCESS FACTORS.................... ..................... ..................... 13

    6. LITERATURE REVIEW AND MODELING PERSPECTIVE.......................... ................. 14

    6.1. Literature Review........................................................................................................................ 14

    6.2. Modeling Perspective ................... ..................... ..................... ..................... ..................... ....... 19

    7. PLAN OF THE PROJECT................................................... Error! Bookmark not defined.

    8. RISK AND RISK AVOIDANCE ........................................... Error! Bookmark not defined.

    9. CONCLUSION ............................................................................. Error! Bookmark not defined.

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    ii

    List of Tables

    Table 1 : Monthly Distribution Graph of Water Coming From Mountain ................. 4

    Table 2 : Monthly Distribution Graph of Water Coming From Mountain for PC ... 5

    Table 3 : Monthly Distribution Graph of Water Coming from Mountain for Pet

    Bottle .......................................................................... ........................................................ ................. 5

    Table 4: Process Flow Diagram ..................................................... ............................................ 8

    Table 5: Ratios of Downtimes ................................................................................................. 12

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    iii

    List of Figures

    Figure 1: Pinar Su Facilities in Turkey .................... Error! Bookmark not defined.

    Figure 2: Market Share of Pinar Su ........................... Error! Bookmark not defined.

    Figure 3: Pet and Polycarbonate sales..................... Error! Bookmark not defined.

    Figure 4: Exporting Sales in Pnar Su....................... Error! Bookmark not defined.

    Figure 5: Pet & Glass Bottle Segmentations and Polycarbonate.6

    Figure 6: Layout of Pinar Su Aydn/Bozdoan Facility.7

    Figure 7: Fishbone Diagram of Breakdown of Machines..11

    Figure 8: Arena Simulation Model Draft..15

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    1

    1. INTRODUCTION

    Pnar Su San ve Tic A.S. is located in Bozdoan / AYDIN and their field of

    activity is spring water bottling and bottle production. Pnar Su is a member of the

    Yaar group which one of Turkeys biggest and most highly respected corporate

    groups.Pinar Su established and started first non-recyclable packaged water

    production of Turkey in 1984 in Izmir, Menderes. Annual production reached

    100.000 tones after the 12 year production in Menderes so facility has moved to

    Bozdoan facility, one of the top-notch waters in the world in terms of taste in 1996.

    Therefore, there are 155 employees and 2 engineers are working in Pnar Su

    Bozdoan.

    2.GENERAL INFORMATION ABOUT PINAR SU

    Sales and distribution network of dealers located all over Turkey. Pinar Su

    has 3 facilities that located in Adapazar, Isparta and Aydn as shown as Figure 1.

    Water which Pnar Su obtains from its Bozdoan, Gkeaa, Akaaa springs is

    supplied to customers in Turkey and in the nearly thirty countries to which the

    company exports. Mineral water supplied to the customer under the most natural and

    hygienic conditions.Natural mineral water sourced from the Bozdoan, Gkeaa

    and Akaaasprings supplied to market in all packaging formats. Bozdoan facility

    is occupying a area of 64.000 m2 and its the biggest facility of Pinar Su. Annual

    production capacities of Bozdoan, Gkeaa, Akaaaare 620.000, 607.000 and

    210.000 tones respectively.

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    Figure 1 : Pinar Su Facilities in Turkey

    Pinar Su is producing 3 main products as pet bottles, glass bottles and

    polycarbonate in Turkey. Their pet segmentations are 0.33, 0.5, 1, 1.5, 5, 10 lt. Glass

    bottle products are 0.33 and 0.75 lt. Polycarbonates are producing as only 19lt.

    Increasing investments of multinational firms like Nestle, Danone, Coca Cola

    is a sign for the growth of the market. Trend in the market to increase the number of

    spring sources in order to optimize logistic cost. Pnar Suscompetitive advantages

    are superior quality standards, logistical strengths, a talent for keeping a close watch

    on national and international customer trends and preferences and transforming them

    into marketable products. In this market conditions, Pinar Su market share is %7 and

    this market share is success against global companies. Small scale local producers

    which occupying %48 as shown as in figure 2 are causing a fragmented market

    structures.

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    Figure 2 : Market Share of Pinar Su

    Pet bottle sales and Polycarbonate sales are biggest parts of market as shown

    as figure 3. According to sales of pet and glass bottles, pet bottles occupying

    approximately %33 of whole sales. Polycarbonate sales percent is approximately

    %67.Pinar Su sales are increasing every year within market share in routine

    conditions. Sales can possibly change according to lack of spring water amount. It

    could be reason to ups and downs in sales.

    Figure 3 : Pet and Polycarbonate Sales

    Pnar Su was exported to Germany for the first time in 1985. As shown as

    Figure 4, Germany has the biggest pie as % 46. England and other countries are other

    important customers of Pnar Su.

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    Figure 4 : Exporting sales in Pnar Su

    3.MICRO SYSTEMS OF PINAR SU

    In Aydn-Bozdoan, there are totally 8 production lines, 6 of them producing

    pet bottle and 2 of them producing glass bottle. Line 1,2,3 are very critical because of

    0.5 and 0.33 pet bottle production. These two segmentations are occupying most of

    all production. In order to reach customer demands, line 1&3 must be working in

    every shift. Line 2 is back-up production line for line 1&3. Other lines are producing

    other segments of pet bottle, glass bottles and 19L polycarbonates.

    Table 1 : Monthly Distribution Graph of Water Coming From Mountain

    0

    5000

    10000

    15000

    20000

    25000

    30000

    Tonnes

    Tonnes

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    Table 2 : Monthly Distribution Graph of Water Coming From Mountain for PC

    Table 3 : Monthly Distribution Graph of Water Coming from Mountain for Pet Bottle

    In these graphs we analyzed the amount of spring water. Therefore we

    analyzed pet bottles and PC respectively. The amount of spring water is increasing

    between April-October months due to weather conditions. In other times, the amount

    of water is not makes a big difference. The interval of amount of water is 5000

    tonnes and 14000 tonnes per year. The most important thing is in these graphs, the

    0

    2000

    4000

    6000

    8000

    10000

    12000

    14000

    16000

    PC Tonnes

    PC Tonnes

    0

    2000

    4000

    6000

    8000

    10000

    12000

    14000

    16000PET Tonnes

    PET Tonnes

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    amount of water make a big increase according to months. In these months every day

    is so precious for company.

    In Aydin Bozdogan facility, there are 6 pet bottle lines, 2 glass bottle lines

    and 2 polycarbonate lines. These production lines are producing 9 different

    segmentation products. These segmentations are 0.33lt, 0.5lt, 0.75lt, 1lt, 1.5lt, 5lt,

    10lt and 19lt polycarbonate. First 5 lines are producing only pet bottles. Line 6 and 8

    are producing glass bottles. Line 7 and 9 are producing 19L polycarbonates.

    Segmentations of pet bottles are 0.33lt, 0.5lt, 1lt, 1.5lt, 5lt and 10lt. Glass bottle

    segmentations are 0.33lt and 0.75lt. Best-seller segmentations of Pinar Su are

    0.33lt&0.5lt pet bottles and 19L polycarbonates.

    Figure 5 : Pet & Glass Bottle Segmentations and Polycarbonate

    Line 1 has 50 tones production capacity per hour. Line 2 has 34 tones

    production capacity for 0.5 lt segmentation and 16 tones production capacity for

    0.33lt segmentation per hour. Line 3 has 89 tones capacity for 1.5lt production

    capacity per hour and line 4 has 30 tones production capacity for 10lt per hour.

    3.1.1. Layout of Facility

    Total production and warehouse area is 64,000m2 in Bozdogan facility and

    enclosed area is 17.000m2. 8 production lines are located side by side. The ninth line

    is located behind of these lines and next to shipping dock. Production lines and

    warehouse are nested. Line 1 and Line 2 are the longest lines of production lines.

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    Other lines lengths are equal each other. All lines are starting after inflating process

    and finish with palletizing, stretching processes. Warehouse area starts from

    palletizing and palletizing process is final process of production. Transportation

    between lines is easy because all lines are parallel. This situation provides early

    intervention ability to workers in production cases.

    Lengths of production lines can change by workers. Current layout is optimal

    layout according to facilitys workers. Length of line 1 & 2 is 11.526 cm. Length of

    lines can decrease or increase by workers according to production needs.

    Figure 6 : Layout of Pinar Su Aydn/Bozdoan Facility

    3.1.2. Processes in Production Lines

    Totally there are 13 stages to produce water in Bozdogan facility. Production

    can be classified as 3 main processes in facility. First main process is transfer of

    spring water, second main process is processing pet preforms (raw material) and

    other main process is basic processes of water bottles. These 3 main processes are

    common in every segment production.

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    Table 4: Process Flow Diagram

    Spring water is transferring from mountain to facilitys total 600 tones water

    tanks with pipelines every single day. Total water amount can change every day

    according to spring water source. Weather conditions are only reason to affects to

    spring water amount. Distance from mountain to facility is 8 km and it provides big

    advantage to facility in order to making production. Quality of spring water is

    another advantage of Pinar Su. After the transferring, spring water waits in water

    tank for a while. Duration of waiting time is up to demands and production plans.

    The water which waiting in water tank goes to ozonation and final process is

    distribution of water to production lines.

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    Meanwhile in raw material area, pet preform are coming with boxes and

    transferring to inflating machine by workers. Inflating machine never starves. Pet

    preform raw materials are always being on hand. Pet preforms goes to two type of

    oven. Temperatures of these ovens are 40 Cand 60 C. After the inflating processes

    for pet preforms, pet preforms transforms to pet bottles and they are preparing for

    washing process. In washing process, bottles turns 360 Cand goes to detailed

    washing via heliozoan machine. Detailed washing is doing by well water.

    At the beginning of third main processes, spring water meets with pet bottles

    and goes to filling process. Remaining steps of production is common for all lines.

    After the filling process, bottle goes to capping process via conveyor. Then following

    processes labeling, shrinking, palletizing and stretching are finishing production and

    products are transferring to warehouse with forklifts.

    4.OBSERVATIONS AND SYMPTOMS

    4.1. Analysis of Production Processes

    Filling-Inflating-Capping: These operations are processing in common

    machine and average 15.000 pet bottles are producing in this machine per hour.

    Another important detail is defective pet bottle units do not pass 25 units during the

    shift. Rotation speed of filling machine is 4000 cycle greater than inflating machine

    and filling amount directly proportional with inflating amount. This system avoids

    collapse in production line. Capping is last process of machine.

    Labeling: Rotation speed of labeling machine is maximum 18.000 cycle per

    hour. Minimum value of rotation is 5000 cycle. In this process, bottles are coming

    one by one then all bottles are going to shrinking process according to pallet size.

    Shrinking: %95 of shrinking processes are processing as 24 bottle pallet size.

    Machine is shrinking 560 packages per hour and 4200 packages in one shift.

    Rotation speed of machine is maximum 24.000 cycle. Duration of bottles shrinking

    is 39 seconds average.

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    Palletizing & Stretching: Palletizing and stretching is last process of all

    production lines. There are two types of stretching. One of them are product

    returned, the other of them is stretch machine returned. Duration of any palletizing

    process is average 7 minutes 21 seconds and duration of any stretching process is

    average 1 minute 54 seconds in normal conditions for 24 bottle pallets. 1 pallet is

    including 7 level and 2016 pet bottles. Segmentation change takes two shift and it

    happens one day in month.

    4.2. SYMPTOMS

    We analyzed firstly breakdown of machines and stated as important

    observation. Fishbone diagram can easily show causes of breakdown of machines as

    seen in Figure 7.

    Figure 7 : Fishbone Diagram of Breakdown of Machines.

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    Fishbone Diagram shows 6 main reason to breakdowns and alternative reasons to

    corresponding main reasons. Main reasons are possibly classified as method,

    management, human, environmental factors, machine and others.

    Method failures are:

    Machine setup

    Cleaning.

    Machine setup times are very critical for production. It can affect to next or previous

    steps of production. Increasing machine setup times absolutely would decrease

    production total speed and amount of outputs. Cleaning is dividing into two type.

    First type is routine cleaning. Every machine is cleaning in every 2 weeks.

    Management failures are:

    Shift Change

    Training

    Shift Change: There are 3 shifts in Pinar Su Bozdogan. Shift are categorized as A, B,

    C. Shift duration is 8 hour. Working production lines can possibly change according

    to shifts. A and B shifts are more intense than night shift C. In A and B shifts are

    producing more products.

    Training: Pinar Su company is giving training sessions to workers at least 2 in a

    month. Training sessions are very important for productivity of facility.

    Human failures are vacations of workers, day-off and breaks in shift.

    Machine failures are most important failure of production system. Problems

    are categorized as maintenance of facility, breakdowns of machines and producing

    defective parts. Most effective failure is breakdown of machines. As well as,

    defected products is very important problem for facilities. On the other hand, Filling

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    machine able to miss bottles to filling. Consequently, this situation causes to lose

    customer satisfaction.

    4.2.1. Analysis of Downtimes in Production Line 1 and Line 2

    Primarily, we collected shift reports from facilitys workers. According to this

    shift reports, we found out total amount of breakdowns of line 1 and line 2 between 1

    February 2014 and 31 March 2014.

    According to our analysis, there were two important downtimes category

    which we classified as method and machine. Method breakdowns are occurring

    mostly in line 2. Machine breakdowns are occurring mostly in line 1. We showed

    this result in our chart as seen in below.

    Table 5: Ratios of Downtimes

    Machine breakdowns are occurring mostly in category which we named as

    machine in fishbone diagram. These machine breakdowns are happening mostly in

    inflating machine of line 1. Biggest reason of this inflating machine breakdown is

    lack of air pressure and insufficient torque.

    Method breakdowns are causing stops in production. Routine cleaning

    operation is constant but machine setups can change according to demands. They

    0

    10

    20

    30

    40

    50

    60

    70

    Machine Method Other

    Causes of Downtimes -%

    Line 1 Line 2

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    need to change product segment and it takes two shift long. Machine setups are

    taking long time. Machine setup is biggest problem of method category and it mostly

    happens in line 2.

    5.PROBLEM DEFINITION, TARGET & CRITICAL SUCCESS

    FACTORS

    Water amount in production lines depends on the arrival of water from

    the spring water source. Our most important goal is determine failures period time.

    Under the lights of symptoms, our problem is to determine the amount of

    produced products from each line when a set of input such as flow rate of water from

    source, mean time of failure given. Arena software simulation program will help us

    to solve this problem. Productivity of production systems would be measured

    through our arena simulation model. Our next critical step is putting values, data and

    results of analyzes into the simulation model respectively. According to simulation

    results, we can forecast our next interference.

    In this project, we examine efficiencies of production lines, utilization of line

    processes and determine optimal amount of produced goods. Determining amount of

    production in lines can help to increase profits of factory and decrease loss of raw

    materials. At the same time, we examine machine breakdowns, machine setups and

    other stoppings of production lines. Within this information, we set up a Arena

    Simulation model to reach our goals.

    5.1. TARGET & CRITICAL SUCCESS FACTORS

    Within this project, in line with the observations and symptoms, we determined

    these issues,

    Inefficient use of production lines

    Low profitability from production lines

    Long setup times and machine breakdowns

    The problem is we look to increasing the efficiency of production lines and the

    profitability from the lines.

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    6. LITERATURE REVIEW AND MODELING PERSPECTIVE

    6.1.Literature Review

    SIMULATION OF MANUFACTURING SYSTEMS

    ABSTRACT

    This paper discusses how simulation is used to design new manufacturing systems and to

    improve the performance ofexisting ones. Topics to be discussed include:manufacturing issues

    addressed by simulation, simulation software for manufacturing applications, techniques for

    building valid and credible models, and statistical considerations.

    MANUFACTURING ISSUES ADDRESSED BY SIMULATION

    The following are some of the specific issues that simulation is used to address in manufacturing:

    The need for and the quantity of equipment and personnel

    Number, type, and layout of machines for a particular objective

    Requirements for transporters, conveyors, and other support equipment (e.g.,

    pallets and

    fixtures)

    Location and size of inventory buffers

    Evaluation of a change in product volume or mix

    Evaluation of the effect of a new piece of equipment on an existing

    manufacturing system

    Evaluation of capital investments

    Labor-requirements planning

    Number of shifts

    Performance evaluation

    Throughput analysis

    Time-in-system analysis

    Bottleneck analysis

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    Evaluation of operational procedures

    Production scheduling

    Inventory policies

    Control strategies [e.g., for an automated guided vehicle system

    (AGVS)]

    Reliability analysis (e.g., effect of preventive maintenance)

    Quality-control policies

    The following are some of performance measures commonly estimated by simulation:

    Throughput

    Time in system for parts

    Times parts spend in queues

    Queue sizes

    Timeliness of deliveries

    Utilization of equipment or personnel

    SIMULATION SOFTWARE FOR MANUFACTURING APPLICATIONS

    Historically, simulation packages were classified to be of two major types, namely,

    simulation languages and applications-oriented simulators. Simulation languages were general in

    nature and model development was done by writing code. Simulation languages provided, in

    general, a great deal of modeling flexibility, but were often difficult to use. On the other hand,

    applications-oriented simulators were oriented specifically toward a particular class of

    applications and a model was developed by using graphics, dialog boxes, and pull-down menus.

    Simulators

    were sometimes easier to learn and use, but might not have been flexible enough for some

    problems.

    However, in recent years vendors of simulation languages have attempted to make their

    software easier to use by employing a graphical model-building approach. A typical scenario

    might be to have a palette of model building icons located on one side of the computer screen.

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    The icons are selected from the palette with a mouse and placed on the work area. The icons are

    then connected to indicate the flow of entities through the system of interest.

    Finally, one double-clicks on an icon to bring up a dialog box where detail is added. On the

    other hand, vendors of simulators have attempted to make their software moreflexible by allowing programming in certain model locations using an internal pseudo-language.

    In at least one simulator, it is now possible to modify existing modeling constructs and to create

    new ones. Thus, the distinction between simulation languages and simulators has really become

    blurred. Based on the above discussion, we will now say that there are two types of simulation

    packages. Ageneral purposesimulation package can be used for any application, but might have

    special features for certain ones (e.g., for manufacturing or process reengineering).

    Examples of general-purpose simulation packages are Arena, AweSim, Extend, GPSS/H, Micro

    Saint, MODSIM III, SIMPLE++, SIMUL8, SLX, and Taylor Enterprise Dynamics Developer. On

    the other hand, an application sorientedsimulation package is designed to be used for a certain

    class of applications such as manufacturing, health care, or call centers. Examples of

    manufacturing-oriented simulators are Arena Packaging Edition, AutoMod, AutoSched, Extend +

    MFG, ProModel, QUEST, Taylor Enterprise Dynamics Logistics Suite, and WITNESS.

    DEVELOPING VALID AND CREDIBLE SIMULATION MODELS

    A simulation model is a surrogate for actually experimenting with a manufacturing system, which

    is often infeasible or not cost-effective. Thus, it is important for a simulation analyst to determine

    whether the simulation model is an accurate representation of the system being studied, i.e.,

    whether the model is valid. It is also important for the model to be credible; otherwise, the results

    may never be used in the decision-making process, even if the model is valid.

    The following are some important ideas/techniques for deciding the appropriate level of model

    detail (one of the most difficult issues when modeling a complex system), for validating a

    simulation model, and for developing a model with high credibility:

    o State definitively the issues to be addressed and the performance measures for

    evaluating

    a system design at the beginning of the study.

    o Collect information on the system layout and operating procedures based on

    conversations

    with subject-matter experts (SMEs).

    o Delineate all information and data summaries in an assumptions document, which

    becomes the major documentation for the model.

    o Interact with the manager (or decision-maker) on a regular basis to make sure that

    the correct problem is being solved and to increase model credibility.

    o

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    o Perform a structured walk-through (before any programming is performed) of the

    conceptual simulation model as embodied in the assumptions document before an audience

    of SMEs, managers, etc.

    o

    Use sensitivity analyses to determine important model factors, which have to be modeled carefully.

    o Simulate the existing manufacturing system (if there is one) and compare model

    performance measures (e.g., throughput and average time in system) to the

    comparable measures from the actual system.

    STATISTICAL ISSUES IN SIMULATING MANUFACTURING SYSTEMS

    Since random samples from input probability distributions drive a simulation model of a

    manufacturing system through time, basic simulation output data (e.g., times in system of parts)

    or an estimated performance measure computed from them (e.g., average time in system from the

    entire simulation run) are also random. Therefore, it is important to model system randomness

    correctly and also to design and analyze simulation experiments in a proper manner. These topics

    are briefly discussed in this section.

    Simulation of Manufacturing Systems

    Modeling System Randomness

    following are some sources of randomness in

    simulated manufacturing systems:

    Arrivals of orders, parts, or raw materials

    Processing, assembly, or inspection times

    Machine times to failure

    Machine repair times

    Loading/unloading times

    Setup times

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    In general, each source of system randomness needs to be modeled by an appropriateprobability

    distribution, not what is perceived to be the mean value. Note that sources of randomness

    encountered in practice are rarely normally distributed. A detailed discussion of simulation input

    modeling is given in Chapter 6 of Law and Kelton (1999).

    Design and Analysis of Simulation Experiments

    Because of the random nature of simulation input, a simulation run produces a statistical estimate

    of the (true) performance measure not the measure itself. In order for an estimate to be

    statistically precise (have a small variance) and free of bias, the analyst must specify for each

    system design of interest appropriate choices for the following:

    o

    Length of each simulation run

    o Number of independent simulation runs

    o Length of the warmup period, if one is appropriate

    We recommend always making at least three to five independent runs for each system

    design, and using the average of the estimated performance measures from the individual runs as

    the overall estimate of the performance measure. (Independent runs means using different random

    numbers for each run, starting each run in the same initial state, and resetting the models

    statistical counters back to zero at the beginning of each run.) This overall estimate should be

    more statistically precise than the estimated performance measure from one run. Note that

    independent runs (as compared to one very long run) are required to obtain legitimate andsimple

    variance estimates and confidence intervals.

    For most simulation studies of manufacturing systems, we are interested in the long-run (or

    steady-state) behavior of the system, i.e., its behavior when operating in a normal manner. On

    the other hand, simulations of these kinds of systems generally begin with the system in an

    empty and idle state. This results in the output data from the beginning of the simulation run not

    being representative of the desired normal behavior of the system. Therefore, simulations are

    often run for a certain amount of time, the warmup period, before the output data are actually

    used to estimate the desired performance measure. Use of the warmup-period data would bias the

    estimated performance measure. A comprehensive treatment of simulation output-data

    analysis can be found in Chapter 9 of Law and Kelton

    (1999).

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    6.2.Modeling Perspective

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    Figure 8 : Arena Simulation Model Draft

    Variables;

    Rated speed of machines Xi;

    The amount of spring water Y;

    Finished goods P

    Parameters;

    Machines(Line 1) Rated Speed per hour

    Inflating 12000

    Filling 14000

    Labeling 12000

    Shrinking 14400

    Palletizing 14400

    Machines(Line 1) Rated Speed per hour

    Inflating 10000

    Filling 14500

    Labeling 14500

    Shrinking 30 pallet/min

    Table6: Parameters of machines in Line 1

    Note: One pallet is formed by 7 floor and one pallet is including 2016 bottle. ( for

    0.5lt pet bottle )

    These data were taken from the company. And we observed these machines

    and they suit the standard numbers. Because of the inflating machines be a first

    machine and its rated speed is the lowest rated speed, there is no any capacity

    problem for other machines.

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    7. SOLUTION METHODOLOGY

    In order to solve this case, we made some literature research then we decided

    to make simulation model. Within this simulation software, we could know that

    actual rate of water which is transferring from spring water and how many tones of

    water should transfer to which lines. And also we could do throughput analysis,

    time-in-system analysis and bottleneck analysis. We had to follow some principles to

    reach our goal. These principles are arrivals of orders, parts, process times of

    machines in lines, machine times to failure, machine repair times and setup times of

    machines. Our research showed us that we had to use discrete event simulation for

    our project. Discrete event simulation has three main advantages in our project.

    Risk avoidance Hypothetical or potentially dangerous systems can be

    studied without the financial or physical risks that may be involved in

    building and studying a real system

    Repeatability The ability to study different systems in identical

    environments or the same system in different environments

    ControlEverything in a simulated environment can be precisely monitored

    and exactly controlled

    After the stating our parameters, we clarified our variables for the model. Our

    three critical variables are rated speed of machines, the amount of spring water, and

    produced goods per lines. These 3 variables are significative factors of simulation

    model. Defining one of these variables, produced goods would also explain our result

    of project. Cause by this way, we can easily state throughput of lines.

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    In order to complete these requirements, we needed to fill some blanks of

    simulation model. First goal was collecting data of production lines. As its

    mentioned in 4.2, our first step was defining breakdown rates of production lines. We

    collected all daily production reports of February, March and June months. These

    daily production data are including breakdowns, machine setups, total amount of

    water which used in production lines and amount of water extravagance as shown

    Figure 9.

    Figure 9: Daily Production Report

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    Figure 10: Daily Breakdown Report

    In this reports, our priority was find out breakdowns rate. This would help us

    in simulation model because we put them to model as machines failures and within

    the failures, we could find real throughput level. We selected all breakdowns fromdaily production reports and copied them to blank worksheet. This separation process

    would help us to analyze data more easily. We opened all single days and shifts of

    reports and completed separation process. After the separation, we separated them

    again and classified them as processes as shown Figure 11.

    Figure 11: Production Report Review

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    We did this separation process for 8 production lines and separate them into

    their processes as 7 worksheets. One worksheet includes process, reason and time of

    breakdowns. These worksheets classified as process names (Bottle Fabrication,

    Ozonation, Labeling, Shrinking, Inflating, Palletizing and Line). We classified

    general breakdowns (which not related to specific processes) as Line. These

    worksheets breakdown frequencies are more than other processes so we eliminated

    processes which happened at most 5 times in 3 months. Finally, we draw a chart of

    these downtimes analysis for Line 1 and Line 2. We picked first two lines because

    their downtime ranges are more than other lines. These charts show us percentages of

    downtimes of Line 1 and Line 2 as seen as Figure 12.

    Figure 12: Percentages of Downtimes.

    Our next step was calculating up times and down times. Up time means time

    between first breakdown and next breakdown of each process. On the other hand;

    Downtime is repair time of each process. (Figure 13) These analyzes are playing

    very critical role in simulation model. Before inserting our breakdown data to model,

    we had one more step to go. We had to convert this data to arena simulation

    softwares language. Input analyzer tool was eligible way to this step. We put our up

    time and down time data to input analyzer and we got a histogram of our data.

    0510

    1520253035404550

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    After following next steps, we found distributions of our data. (Arena ->

    Tools -> Input analyzer -> Fit -> Fit all).Then, we collected all input analyzer data of

    production lines in one excel sheet. That excel sheet shows distributions and p-values

    of data according to chi-square test as shown as Figure 14 and we showed input

    analyzer results in figures 15 and 16.

    Figure 13: Down time and Up Time Excel Sheet

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    Figure 14: General distributions of breakdowns of lines.

    Figure 15: Input Analyzer for Line 3 ( Down Time)

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    Figure 16: Input Analyzer for Line 3 ( Up Time)

    During the input analyzer work, determining p-value was very important

    because p-values are giving an idea about our data. We only needed to reach ( p