P&LProcess

77
Process Introduction. Types of Processes. Process Strategy in the industry. Factors affecting Process Design. Tools

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    Process

    Introduction.

    Types of Processes.

    Process Strategy in the industry.

    Factors affecting Process Design.

    Tools

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    Process Introduction

    Classification of Processes Process strategies at the Industry

    Factors that affect (or are affected by) the ProcessSelection.

    Tools SPC, SMED

    Documents

    Work Measurement and Standards

    Job Place Design

    Line Balancing

    Measuring Process Performance

    Queueing Theory

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    Introduction The information generated during the product design phase specifies

    how the product must be, but not how to organize the productionprocess to make it (equipment, labor skills required, etc.).

    Process Design specifies how the activities that Operations must carry

    out should be developed:

    Guiding the election and selection of technologies.

    Clarifying the quantity and type of resources to be acquired, when to beacquire and their availability.

    Process design and redesign is intimately related to Product Design:

    Concurrent or Simultaneous Engineering.

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    Process Selection and System Design

    Forecasting

    Product and

    Service Design

    Technological

    Change

    Capacity

    Planning

    ProcessSelection

    Facilities and

    Equipment

    Layout

    Work

    Design

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    Process Introduction

    Classification of Processes Process strategies at the Industry

    Factors that affect (or are affected by) the ProcessSelection.

    Tools SPC, SMED

    Documents

    Work Measurement and Standards

    Job Place Design

    Line Balancing

    Measuring Process Performance

    Queueing Theory

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    The process-focused Project ShopCharacteristics

    1. Unique products with certain complexity (boats, aircrafts, trains, motorways)

    2. The production process is managed like a project3. Makes a one-of-a-kind product (volume = 1)

    4. Uses general purpose equipment

    5. Has informal relationships with many vendors

    6. Very little vertical integration

    7. Flexible layout often with factors of production moving to job

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    TheJob ShopA process structure suited for low volume production of a great variety of non-standard

    products (highly customized products).

    Custom or workshop: Low specialized operations carried out by the same worker or groupof workers that follow up the whole process for the order.

    Batch: More specialized operations carried out by different workers or group of

    workers (need for more specialization and standardization).

    Characteristics

    1. Makes many products in small volume

    2. Uses general purpose equipment, grouped by the same function in Work Centres

    3. Has informal relationships with vendors

    4. Very little vertical integration

    5. Departmentalized layout with chaotic flow

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    The Large Batch (Cell, Flow Shopor

    Hybrid Shop)

    A process structure that produces a variety of standard

    products at relatively low volumes. This variety of

    standard products has a similar sequence of operations:

    The equipment is laid out in line, instead of grouped by

    the same function.

    After completing one batch, equipment adjustments for

    the next one are made and the next batch produced.

    Characteristics

    1.Makes several families of products in moderate volume

    2.Uses general purpose equipment often customized

    3.Little vertical integration

    4.Similar product follows the same path, produced inbatches to reduce the impact of setup time.

    5.Hybrid layout with flow lines

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    A process structure designed to make discrete parts. Parts are moved

    through a set of specially designed workstations at a controlled rate.

    Characteristics

    1.Makes few products in large volume

    2.Uses specialized high-volume equipment

    3.Has formal relationships with vendors

    4.May use vertical integration

    5.Product-based layout with linear flow

    Assembly Line

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    Continuous FlowAn often automated structure that converts raw

    materials into finished products in one continuousprocess.

    Same operations are made in the same equipment to make

    the same product, reducing waiting time.

    Objectives: Improvement of material flow and operations.

    Workers specialization:

    Increasing speed and added value.

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    Types of Processes Flexibility and Costs

    By Projects

    Job Shop

    Flow Shop

    Assembly Line

    Continuous

    Flexibility

    Fixed CostVariable Cost

    Unit Cost

    +

    - +

    -

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    Process Introduction

    Classification of Processes Process strategies at the Industry

    Factors that affect (or are affected by) the ProcessSelection.

    Tools SPC, SMED

    Documents

    Work Measurement and Standards

    Job Place Design

    Line Balancing

    Measuring Process Performance

    Queueing Theory

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    Process Strategy in the industry

    Manufacturing Process Life Cycle

    Processes go through different phases as

    products do.

    Interdependency between Product and

    Process Life Cycles: Process Life Cycle: Affects manufacturing costs,

    quality and production volumes, which affects

    sales volumes.

    Product Life Cycle: Influences the type of

    manufacturing process that can be economically

    and financially justified.

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    Process Strategy in the industry

    Product-Process Matrix

    IV.

    Continuous

    Flow

    III.Assembly

    Line

    II.

    Batch

    I.

    Job

    Shop

    Low

    Volume,

    One of a

    Kind

    Multiple

    Products,

    Low

    Volume

    FewMajor

    Products,

    Higher

    Volume

    HighVolume,

    High

    Standard-

    ization

    CommercialPrinter

    French Restaurant

    Heavy

    Equipment

    Automobile

    Assembly

    Burger King

    Sugar

    Refinery

    Flexibility (High)

    Unit Cost (High)

    Flexibility (Low)

    Unit Cost (Low)

    These are

    the major

    stages ofproduct and

    process life

    cycles

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    Process Strategy in the industry The Product-Process matrix and the Competitive Advantage

    The Product-Process matrix helps companies define where theircompetencies are, concentrating their attention in a limited groupof decisions and process alternatives, as well as a limited groupof Marketing options.

    When the company considers at the same time products andprocesses, it can increase its probability of success.

    Place in the matrix and Competitive priorities

    Organization of the Operations and the Product-Processmatrix

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    Process Strategy in the industry The Product-Process matrix and the Competitive Advantage

    Place in the matrix and Competitive priorities Operations Management priorities change as the Product-

    Process combinations change.

    I.e.- Flexibility vs. Standardization

    Each company has to take into account its traditional focus when

    positioning in the matrix: Market oriented: Flexibility and Quality.

    Manufacturing oriented: Costs and Process Leadership.

    Organization of the Operations and the Product-Processmatrix

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    Process Strategy in the industry The Product-Process matrix and the Competitive Advantage

    Place in the matrix and Competitive priorities Organization of the Operations and the Product-Process matrix

    Paying attention to the process that makes the company morecompetitive, the company will be able to manage thedevelopment of the operations involved per line of products.

    The knowledge about how the different positions in the matrixaffect manufacturing will lead the company to suggest changes inOperations Management.

    Companies that compete with several products in differentmarkets will probably have their products in different stages of thelife cycle:

    Companies should separate and organize their processes in differentareas focalized in the different life cycles.

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    Process Introduction

    Classification of Processes Process strategies at the Industry

    Factors that affect (or are affected by) the ProcessSelection.

    Tools SPC, SMED

    Documents

    Work Measurement and Standards

    Job Place Design

    Line Balancing

    Measuring Process Performance

    Queueing Theory

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    Process Selection and System Design

    Forecasting

    Product and

    Service Design

    Technological

    Change

    Capacity

    Planning

    ProcessSelection

    Facilities and

    Equipment

    Layout

    Work

    Design

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    Factors affecting Process Design

    Capital Investment

    Flexibility

    Vertical Integration / Outsourcing

    Nature of Demand

    Quality of the product or service

    Customer participation

    The Learning effect

    Financial Planning and Evaluation

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    Factors affecting Process Design

    Capital Investment

    Combination of equipment and human resources

    at the manufacturing process.

    The new manufacturing technologies provide a

    wide variety of available options: As the mechanical and/or automated operations

    increase, more capital is required.

    Most of the available options require a high capital

    investment, which create a high risk in case our sales

    volumes (and therefore our production volumes) arelower than the expected.

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    Factors affecting Process Design

    Flexibility

    A production process is more flexible when their

    equipment and human resources are able to

    manage a wider variety of products, outputs,

    responsibilities and functions, at a reasonable

    cost and time frame.

    Capital vs. Flexibility

    Flexibility

    Capital

    Traditional

    technologies

    New

    technologies

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    Factors affecting Process Design

    Flexibility

    Flexibility affects the type of human resources

    required and their job stability:

    More training is required.

    Job stability is more variable for companies working by

    projects or job shop type of process.

    Flexibility is one of the best ways to get a reliable

    customer service and reduces bottle necks.

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    Factors affecting Process Design Vertical Integration/Outsourcing

    The degree of vertical integration is related to the numberof processes at the supply chain that are carried out by theown company.

    The vertical integration can generate savings when thecompany has the necessary skills to carry out some

    processes at a lower cost and better quality. If the resources acquired are basic, the company may

    loose competitiveness with non-vertical integration.

    Outsourcing is interesting when a resource consumption islow, and its efficient management has a certain economy of

    scale. Outsourcing is used as well when the technology to be

    used is so complex that being competitive requires a bigeffort not balanced with the benefits obtained.

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    Factors affecting Process Design Nature of the demand

    Manufacturing processes have to have the necessary capacity tosupport the demand of products and services that the company is

    going to offer.

    Seasonality, tendency and other characteristics of the demand are

    going to affect the capacity required over the time.

    Some processes are able to expand and contract more easily than others. The final selection of processes will be affected by the estimated demand.

    Price:

    If its high, consumers will tend to buy less and vice versa.

    To fix the price, the company has to take into account factors like

    advertising costs, sales force, financial conditions, services provided to thecustomer, specific designs, inventory and delivery policy, quality, etc., at

    the same time than the costs related to manufacturing.

    It should be coordination between product price and process selection, due

    to the competitive advantages provided by the different types of processes

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    Factors affecting Process Design Quality of the product or service

    Quality is a competitive advantage in the current businessenvironment.

    The level of quality to be offered will affect directly the selection of the

    production process.

    The level required is directly related to the level of automation of the

    process, since the automatic equipment manufactures products witha high and consistent uniformity.

    Customer participation

    Services that require higher contact with the customer generally

    need less capital investment and have more flexibility.

    Customer presence normally affects the process efficiency in anegative way, which increases cost.

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    Factors affecting Process Design The Learning effect

    The working hours required per unit of product represent adecreasing function of the number of cumulative production units.

    This reduction of working hours (and therefore cost) are

    based on the gain of experience in design of products and

    services, automation and capital investment, as well as

    changes in methods and experience of the working force. Companies competing in price try to have high

    manufacturing volumes to take advantage of the learning

    effect, and therefore have a lower cost.

    Production volume

    Working

    hoursperunit

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    Factors affecting Process Design

    Financial Planning and Evaluation

    Operation managers are continuously looking for

    new and different ways of producing that:

    Increase productivity.

    Follow the Operations Strategy.

    Provide sufficient profit to justify the capital investment

    required.

    Each type of process has different capital

    requirements, thus limiting the companys

    possibilities of process selection in case of limited

    financial resources.

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    Process Introduction

    Classification of Processes Process strategies at the Industry

    Factors that affect (or are affected by) the ProcessSelection.

    Tools SPC, SMED

    Documents

    Work Measurement and Standards

    Job Place Design

    Line Balancing

    Measuring Process Performance

    Queueing Theory

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    Tools and Concepts

    Simplify/Mechanize/Automate/Integrate

    SMED

    CAD/CAM

    Statistical Process ControlBottlenecks

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    How much is the profit?

    A company manufactures 2 products P & Q. Sale price of P is

    90and Q price is 100/unit. Weekly Demand is 100 units for Pand 50 units for Q.

    Both products require the same PC component, the rawmaterial of which worths 20 /unit. To transform PC 15 minutesof a given resource B are required and 5 minutes of a givenresource C.

    Product P also requires Component 1 (C1) that should betransformed from a raw material that cost 20 /unit, and itrequires 15 minutes of a given resource A and 10 minutes of C.

    To assembly PC with C1 a new component C3 is required witha cost of 5/unit and 5 minutes of the D resource.

    Product Q follows a very similar process. To manufacture C2raw material with a cost of 20 /unit is needed, and it isprocessed using 20 minutes of A and 15 minutes of B. Thenresource D assembles PC with C2 during 5 minutes.

    Each week has 5 days of 4 hours. Total cost are 3600/week.

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    Process Introduction

    Classification of Processes Process strategies at the Industry

    Factors that affect (or are affected by) the ProcessSelection.

    Tools SPC, SMED

    Documents

    Work Measurement and Standards

    Job Place Design

    Line Balancing

    Measuring Process Performance

    Queueing Theory

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    Work Measurement and Standards The Purpose of Work Measurement is to set time standards for a job.

    Such standards are necessary for 4 reasons:

    To schedule work and allocate capacity. To provide an objective basis for motivating the workforce.

    To bid for new contracts and to evaluate performance on existing ones.

    To provide benchmarks for improvement.

    Methods

    Time Study (stop watch) Work Sampling (observing a sample)

    Predetermined times

    Elementary standard data

    Reference points.

    Reference Book (B.W. Niebel, Motion and Time Study)

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    Time Study A time study is generally made with a stopwatch, either on the spot

    or by analyzing a videotape for the job. The job or task to be studied is separated into measurable parts

    and then timed individually.

    Some general rules

    Define each work element to be short in duration but long enough

    to be timed and the time can be written Separate activities related with machine from the rest.

    Define any delays or acyclic activities.

    After a number of repetitions, collection times are averaged.

    Normal Time = Observed Performance Time x Performance Rating

    Standard Time = NT x (1 + Allowances)

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    Work Sampling Three primary applications

    Determine the activity-time percentage for personnel orequipment.

    Performance measurement to develop a performance index forworkers.

    Evaluate time standards to obtain the standard time for a task.

    Five Steps Identify the specific activities that are the main purpose for the

    study.

    Estimate the proportion of time of activity of interest of the totaltime.

    State the desired accuracy in the study results.

    Determine the specific times when each observation is to bemade.

    At two or three intervals during the study period recompute therequired sample size by using the data collected thus far.

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    Get Put

    Move with Weight (5 UMT)

    Grasp (6 UMT)

    Bend Down (29 UMT)

    Stand up (32 UMT)

    Apply Presure (14 UMT)

    Eye Movement (7 UMT)

    Step (18 UMT)

    Coger funda GDF 25

    Coger "tinta" GDF 25Poner "tinta en funda" PDN 19

    Coger y Poner GEN+PEN 5+8

    Aplicar Presin 14

    Coger caperuzn GDF 25

    Reajustar tras coger 6

    Poner caperuzn PDN 19

    Aplicar Presin 14

    Dejar bolgrafo PEF 14

    6.3 seconds

    N X F

    PE 5 9 14

    PD 19 22 28

    N X FGE 8 13 16

    GD 17 20 25

    Predetermined Motion Times (MTM, MODAPTS, )

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    Process Introduction

    Classification of Processes

    Process strategies at the Industry

    Factors that affect (or are affected by) the ProcessSelection.

    Tools SPC, SMED

    Documents

    Work Measurement and Standards

    Job Place Design

    Line Balancing

    Measuring Process Performance

    Queueing Theory

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    Documents Flowchart.A flowchart is a

    graphical representation of aprocess, depicting inputs,

    outputs and units of activity. Itrepresents the entire process ata high or detailed (depending onyour use) level of observation,allowing analysis andoptimization of workflow.It canserve as an instruction manual.

    Assembly Drawing: Anexploded drawing containing aset of number parts combined tomake a complet product.

    Value Stream Map: Value

    stream mapping is a paper andpencil tool that helps you to seeand understand the flow ofmaterial and information as aproduct or service makes itsway through the value stream.

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    Operation

    Begin or end

    Information

    input

    Information

    output

    Shampoo directions

    1. Lather

    2. Rinse3. Repeat

    Process Documentation using Flowcharts

    Basic flowchart symbols

    Example: Any problems

    with the followingset of directions?

    Question

    yes/no?

    Shampoo?

    Begin shampoo

    Rinse hair with

    warm water

    Lather shampoo

    into hair

    Select bottle

    Wet hair with

    warm water

    Information

    on bottle

    No

    Yes

    Hair

    clean?

    NoEnd shampoo

    Yes

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    Process Flow Diagram (PFD)A process flow diagram is a mapping of the specific processes that raw materials

    parts, and subassemblies follow as they move through a plant.

    Builds on the concept of flowcharting.Activity

    A more constrained version of the operation symbol used in flowcharting

    1. Requires a resource

    2. Resource has a capacity constrain

    3. Adds value

    Flow

    1. Arrow indicates the flow of jobs

    2. Multiple flow units (types of jobs) possible

    Buffer

    Buffer or inventory location

    1. Normally does not have a capacity

    2. Multiple units possible

    Trees

    RM

    DebarkStems

    WIP

    Scan SawAcceptable

    Lumber

    FG

    GrindChips

    FG

    Acceptable

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    Flow Diagrams

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    Single Object Process Chart

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    Assembly Process Chart Assembly charts

    Disassembly charts

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    Action Decision Flow Diagram

    M l i A i i Ch

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    Multi Activity Charts

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    Process Introduction

    Classification of Processes

    Process strategies at the Industry

    Factors that affect (or are affected by) the ProcessSelection.

    Tools SPC, SMED

    Documents

    Work Measurement and Standards

    Job Place Design

    Line Balancing

    Measuring Process Performance

    Queueing Theory

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    Job Design (I)

    Job design is the function of specifying the work activities of an

    indidividual or a group in an organizational setting. The objective is to develop job structures that meet the

    requirements of the organization and its technology and thatsatisfy the job holders personal and individual requirements.

    Trends of Job Design Decisions Quality control as part of the workers job

    Cross training workers to perform multiskilled jobs Employee involvement and team approaches to designing and

    organizing work

    Informating ordinary workers through internet, email

    Extensive use of temporary workers

    Automation of heavy manual work

    Organizational commitment to providing meaningful and rewardingjobs for all employees.

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    Job Design (II) The improvement of the job methods leads to a higher level of

    specialization.

    A workplace with a high level of specialization covers a narrow set oftasks, high repetitive levels, and, hopefully, high efficiency and quality.

    Specialization produce benefits as quicker training and faster workingrates.

    This way of working has also some disadvantages as workerdemoralization, reduces flexibility and increases the work of upper levelsof management.

    To avoid those disadvantages: Wider jobs

    Job enlargement (horizontally expanded)

    Job enrichment (vertically expanded)

    Job Rotation

    Socio-Technical Systems Task variety

    Skill variety

    Feedback

    Task identity

    Task autonomy

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    Process Introduction

    Classification of Processes

    Process strategies at the Industry

    Factors that affect (or are affected by) the ProcessSelection.

    Tools SPC, SMED

    Documents

    Work Measurement and Standards

    Job Place Design

    Line Balancing

    Measuring Process Performance

    Queueing Theory

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    Line Balancing

    Introduction

    Line Balancing

    Mathematical Programming Model

    Heuristic Methods

    Yamazumi

    Duration of the Tasks Longer than Cycle Time

    Other Considerations.

    Mixed Model Assembly Line

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    Introduction

    The design of the line, constraints the alternatives whenscheduling the activity of the line.

    A decision on the productive system (in the long term):

    Defines the allocation of facilities.

    Constrains the sequence (lines with mixed models).

    Constrains the production volumes (lines multi-model).

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    Assembly line

    Manufacturing

    Made and bought inventory of

    components and subassemblies

    Conveyor moving at constant speed

    WorkStation 1

    WorkStation 2

    WorkStation m

    Final

    product

    inventory

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    1 2 3 4 NIn Out

    1 2 3 4 NIn Out

    1 2 3 4 NIn Out

    single model line

    batch model line

    mixed model line

    Production Organization

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    Use of the Assembly line

    Advantages

    Performance increase due to the learning effect.

    Reduces the difficulty of the task.

    Increases the team work, avoiding isolations. Constant rate of work.

    Ongoing quality control.

    Disadvantages

    Alienation.

    Less flexibility.

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    Line Balancing. Definition.

    Line Balancing consists of assigning operations to theworkstations of such form that the sum of their durations ineach station is as similar as possible.

    With this procedure bottlenecks should be avoided,

    unproductive time will be reduced and the productivity ofthe line will increase.

    This implies that:

    Each operation will be assigned to an one only and onlyone workstation.

    Relations and bounds between operations will berespected.

    Times of the stations will not exceed their cycle time.

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    Objectives.

    Capacity Minimization of total idle time (maximization of the use of the

    line).

    Minimization of product flow-time.

    Balance the levels of capacity used at the workstations.

    Cost

    Minimization of the machinery costs, tools or idle equipment.

    Minimization of the costs of materials or reworks.

    Minimization of the costs by adjustment and change.

    Organizational-social Job Enrichment

    Modifications at the Line balancing

    General definitions (I)

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    General definitions.(I) Operation:Smaller unit of work than cannot be divided without creating an

    unnecessary interference.

    Workstation:Segment of the line where a set of operations is executed.

    Characterized by its surface, machinery or type of assigned work. Line Balancing:Process to assign operations to workstations. It intends to

    assign personal or equipment of efficient way to obtain the performancemaximum.

    Cycle time:Amount of time between two consecutive products.

    Balance Efficiency: It indeed represents the percentage of invested totaltime in making products.

    Station Pitch:The distance of a product and the one that follows to him inthe conveyor belt.

    ProductionForecast

    TimeAvalaibleTimeCycle

    Stations NxCycle Time

    Operations Total TimeEfficiency

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    General Definitions. (II) Bounds between operations.

    Precedence Relations.

    Imposed generally by technological constraints.

    Operation'' cannot be made if before the 'h' has not

    taken place

    In the case of linear configurations, this implicates

    that 'h' will have to be in the same station that 'i' or in

    a previous one, but never in a following one.

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    General Definitions. (III) Positive Zoning.

    It is compulsory to locate an operation in

    the same station that another one.Operations that need the same toolOperations that need the same ability on the part of the

    workerOperations that need the same physical training conditions

    Negative Zoning or incompatibility.

    It is demanded that an operation is not inthe same station that another one.

    Position of the unit in the line (Operations to be made at theright side

    are not compatible with those to be made at the left)

    Exigency of a high specialized workers

    Processes of painted sandpapering and of surfaces

    Allocation of varied activities to avoid monotony.

    Limit Zone.

    It is demanded that certain operations areassigned to stations previous or next toone given

    Fixed zone of material arrival.

    Zone of preparation or control.

    G l D fi i i ( V)

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    General Definitions. (IV)

    ji

    ij tTO m1,...,=j;

    Line Speed

    Productivity

    Operation Time in a station

    Minimum number of workstations

    LV=L/C

    CP

    1

    C

    t

    N

    n

    i

    i

    ws

    1

    1 minute

    TOTO 1 minute

    C C

    G l D fi i i (IV)

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    General Definitions. (IV)

    Idle time of a station

    Total idle time of a station or delay

    Station saturation

    Efficiency

    Delay

    n

    i

    i

    m

    j

    j tCmTOCD11

    )(

    ...

    0.9 minutes

    1 minute1 minute

    m1,...,=j;ij TOCDI

    m1,...,=j;CTOS ij

    100(%) 1

    Cm

    t

    E

    n

    i

    i

    (%)100(%) ER

    Li B l i

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    Line Balancing

    Introduction

    Line Balancing

    Mathematical Programming Model

    Heuristic Methods

    Duration of the Tasks Longer than Cycle Time

    Other Considerations.

    Mixed Model Assembly Line

    Resolution Procedures for problem SALBP 1

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    Resolution Procedures for problem SALBP 1.

    Exact methods

    Mathematical Programming Models

    Exact algorithms of directed exploration and dynamic

    programming.

    Heuristic methods

    Constructive. Based on rules and strategies

    Heuristic of a single one happened.

    Simple

    Composed

    Heuristic with backward movement

    Approaches from exact algorithms

    Others

    Model of PLM of problem SALBP1

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    Model of PLM of problem SALBP1.

    Variables of allocation xij:

    Binary variables that they

    indicate if operation i is

    assigned to station j.

    Variables of existence yj:

    Binary variables that theyindicate if station j exists.

    This existence comes

    imposed when not being

    able to assign but

    operations to anyone of

    the stations already

    defined.

    mmax

    j

    jyzMIN

    1sujeto a:

    mmax

    j

    jix1

    , 1 i=1n [1]

    n

    ijjii yCxt

    1, j=1mmax [2]

    mmax

    j

    mmax

    j

    jpji xjxj1 1

    ,, i precede a p [3]

    ij yy 1 j=1mmax-1 [4]

    jix ji ,1,0,

    jy j 1,0

    H ri ti pr d r

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    Heuristic procedures Although nonexact, some heuristic

    procedures provide solutions thatcan be considered acceptable.

    The known procedures of

    constructive type more are the

    bound ones to the duration of the

    task or the number of consequent. One of them chooses to assign to

    the open station the task with

    greater duration than still it fits in the

    station.

    The alternative procedure chooses

    to assign to the open station the

    task with greater number of

    consequent.

    Y i

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    Yamazumi

    1

    2 3

    4

    5 6

    7

    8

    9

    10

    11

    12

    CY

    C

    L

    E

    TI

    M

    e

    Obj i

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    Objectives.

    Capacity Minimization of total the idle time (maximization of the use of

    the line).

    Minimization of products flow-time in the line.

    Balance the levels of capacity use at the workstations.

    Cost

    Minimization of the machinery costs, tools or idle equipment.

    Minimization of the costs of materials or reworks.

    Minimization of the costs by adjustment and change.

    Organizational-social Job Enrichment

    Modifications in the Line balancing

    Li B l i

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    Line Balancing

    Introduction

    Line Balancing

    Mathematical Programming Model

    Heuristic Methods

    Yamazumi

    Duration of the Tasks Longer than Cycle Time

    Other Considerations. Mixed Model Assembly Line

    A real Example

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    Operation Time Preceding Task Operation Time Preceding Tas1 0,175 - 16 0,200 -

    2 0,139 - 17 0,084 -

    3 0,078 1 18 0,116 13;15

    4 0,349 - 19 0,199 18

    5 0,007 - 20 0,079 19

    6 0,050 - 21 0,103 19

    7 0,211 4 22 0,098 98 0,158 - 23 0,116 19

    9 0,230 8 24 0,210 23

    10 0,080 9 25 0,140 24

    11 0,075 - 26 0,210 25

    12 0,395 9 27 0,177 26

    13 0,219 12 28 0,234 2714 0,188 - 29 0,090 -

    15 0,122 12

    A real Example

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    1

    2

    3

    4

    56

    78

    17

    18

    19

    20

    212223

    24

    25

    26

    27

    28

    29

    16

    14 9

    12

    13

    1510

    11

    Yamazumi Graphics Example

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    1

    2

    3

    4

    56

    78

    17

    18

    19

    20

    2122 23

    24

    25

    26

    27

    28 29

    1614

    9

    12

    13

    1510

    11

    Yamazumi Graphics Example

    Process

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    Process Introduction

    Classification of Processes

    Process strategies at the Industry

    Factors that affect (or are affected by) the ProcessSelection.

    Tools SPC, SMED

    Documents

    Work Measurement and Standards

    Job Place Design

    Line Balancing Measuring Process Performance

    Queueing Theory

    Measuring Process Performance

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    Measuring Process Performance

    Productivity: Ratio of Output to Input

    Effiency: Ratio of Actual output to some standard.

    Utilization: Ratio of the time that a resource is actually activatedrelative to the time that it is available for use.

    Cycle time (takt time): Average time between the completion ofsuccesive units.

    Run Time: time required to produce a batch of parts

    Setup Time: is the time required to prepare a machine to make aparticular item.

    Operation Time: sum of setup and run time.

    Throughput time: time that unit spents actually being transformedor waiting.

    Throughput rate: output rate that the process is expected toproduce over a period of time.

    Process velocity: Total throughput divided by Value Added Time

    Value Added Time: Time that useful work is actually done

    Process

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    Process Introduction

    Classification of Processes

    Process strategies at the Industry

    Factors that affect (or are affected by) the ProcessSelection.

    Tools SPC, SMED

    Documents

    Work Measurement and Standards

    Job Place Design

    Line Balancing Measuring Process Performance

    Queueing Theory

    Queueing Theory

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    Queueing Theory Littles Law: The size of a queue is proportional to the input

    rate and the average throughput time.

    L= W

    Lq = Wq

    1

    qWW