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28207305-The-Various-Types-of-Production-Systems-and-their-Importance

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    PROJECT REPORT

    ON

    IMPORTANCE OF

    PRODUCTION SYSTEMS

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    INDEX

    1) Introduction

    2) Factors Influencing Manufacturing System

    3) Classification Of Manufacturing System

    4) Intermittent Production System

    Project

    Job

    Batch

    5) Continuous Production System

    Mass

    Flow

    Process

    6) Just In Time Production System

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    INTRODUCTION

    Production is a conversion function by which goods and services areproduced. A typical production system comprises of three main components:

    Inputs, Transformation process and Output.

    (i) Inputs are men, materials, machines, instructions, drawings, and paper

    work and instructions.

    (ii)The Transformation Process involves operations, mechanical or

    chemical, to Change/convert inputs into outputs. It also includes activities

    that assist conversion,

    Typical examples are

    Planning and control of factors of production.

    Procurement of materials.

    Receipt, storage and issue of materials.

    Material handling (to move materials to the point of use.)

    Inspection of ill-process and parts.

    Assembly and testing of products. Storage of finished goods.

    Instructions, authorizations, inspections, information storage/retrieval

    etc.

    (iii) Output is goods and services (e.g. products, parts, paper work, served

    customers etc.

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    The combination of operations and activities stated above employed

    to create goods and services are known as manufacturing system. A

    manufacturing system therefore may be looked upon as an independent

    group of sub-systems, each sub-system performing a distinct function.

    Different sub-systems may perform different functions, yet they are inter-

    related and require to be unified to achieve overall objectives of the

    organization.

    Manufacturing system needs to interact with both internal and externalenvironment. The internal environment is the combination of engineering,

    marketing, personnel and accounts activities whereas external environment

    comprises of customers, competitors, suppliers, labor unions etc.

    The selection of the manufacturing system is a strategic decision for most

    organizations since changes at a later date arc very expensive to make. The

    systems selected should be such that it can give the desired output, required

    quality and is cost-effective.

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    FACTORS INFLUENCING CHOICE OFMANUFACTURING SYSTEM

    There is no best manufacturing system for any product. The choice of thesystem depends on various circumstances but it must meet two basic

    objectives, namely -

    (i) It must be able to meet the specifications of the final product, and

    (ii) It must be cost effective

    The product specifications can be met by choosing the right technology but

    that is not always an easy task. Since stricter specifications add to the cost of

    the product, there is always a trade off between the desired specifications

    and the cost to achieve such specifications. For example, sophisticatedinjection moulding machines and high quality plastics can produce excellent

    dolls cheaply provided they are produced in volume. However, if their

    demand is limited, they may not be able to compete with home made dolls

    produced in small quantities and sold at a fraction of the price of the

    moulded version.

    Various factors which determine the choice of the manufacturing process are

    as follows:

    (a) Effect of volume/variety

    One of the major considerations in the process selection is the

    volume/variety of the products.

    Relationship between degree of repetitiveness & transformation Process

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    High product variety require highly skilled labour, general purpose

    machines, detailed production planning and control system.

    On the other hand low product variety (i.e. one or few products produced in

    large volumes) enables the use of low skilled labor, highly automated mass

    production processes using special purpose machines and simple productionplanning and control systems.

    Fig. exhibits the relationship between output and the transformation process.

    The horizontal axis shows the degree of repetitiveness represented in terms

    of batch size, one end showing the products produced in batches of one and

    other end representing products produced in very large batch sizes.

    The vertical axis represents the transformation process, the top representing

    the project form where each project is followed by another (no two projects

    being alike) and the bottom representing the process form where the single

    product with highly continuous material flow (e.g. as in refinery, sugar mill)is produced.

    Shaded area in each bar suggests the manufacturing system desirable for the

    indicated volume. Unshaded area in the lower portion of the column implies

    that it is inadvisable to use the continuous form when the batch is really

    small. Similarly, when the batch is really large, it is not at all advisable to

    use the project form.

    For these reasons, decisions involving process selection must be taken while

    formulating the corporate strategy of the firm

    (b) Capacity of the plant

    The projected sales volume is a major influencing factor in determining

    whether the firm should go in for intermittent or continuous process. Fixed

    costs are high for continuous process and low for intermittent process while

    variable costs are more for the intermittent process and less for continuous

    process. Intermittent process therefore will be cheaper to install and operate

    at low volumes and continuous process will be economical to use at high

    volume.

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    Effect of volume on manufacturing process selection

    (c)Flexibility

    Flexibility implies the ability of the company to satisfy varied customers

    requirements. Flexibility and product variety are inter-related. If more

    variety is to be manufactured, the manufacturing facilities will have to becommonised and depending upon the volume, the extent of commonalities

    will require to be justified. Greater commonalities demands intermittent

    manufacturing which is associated with higher inventories, large

    manufacturing lead times and elaborate planning and control.

    (d) Lead time

    Lead times more appropriately called delivery lead times expected by the

    customers (i.e. how soon the demand has to be met without losing on sales)is another major influencing factor in a competitive market. As a general

    rule, faster deliveries are expected in a competitive market. The product,

    therefore, may require to be produced to stock using principles of batch

    production/mass product

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    (e)Efficiency

    Efficiency measures the speed and the cost of the transformation process.

    Efficiency is the greatest when the product is mass producted. But to mass

    produce a product, greater sales volumes are required. Therefore, depending

    upon the sales volume, product variety will have to be considered and theprocess which will give the best efficiency in terms of machine and

    manpower utilization will have to be selected.

    (f)Environment

    Environment brings in new technologies and forces the adoption of new

    process of manufacturing. For example, wooden furniture is gradually being

    replaced by metals and plastic. A furniture manufacturing unit will have to

    change its technology (i.e. change from one off production to batchproduction) to fall in line with changing times. Similarly, as market

    preferences change due fashions or other reasons, the manufacturing process

    has to be changed accordingly.

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    CLASSIFICATION OFMANUFACTURING SYSTEMS

    Classification of manufacturing system

    INTERMITTENT SYSTEM

    In this system, the goods are manufactured specially to fulfill orders made

    by customers rather than for stock. Here the flow of material is intermittent.

    Intermittent production systems are those where the production facilities are

    flexible enough to handle a wide variety of products and sizes. These can be

    used to manufacture those products where the basic nature of inputs changes

    with the change in the design of the product and the production process

    requires continuous adjustments. Considerable storage between operation is

    required, so that individual operations can be carried out independently for

    further utilization of men and machines. Examples of intermittent system

    are: machine shops, hospitals, general office etc.

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    Chief characteristics of intermittent system are: -

    (i) Most products are produced in small quantities

    (ii) Machines and equipment are laid out by process.

    (iii) Workloads are generally unbalanced.(iv) Highly skilled operators are required for efficient use of machines and

    equipment.

    (v) In-process inventory is large.

    (vi) Flexible to suit production varieties.

    Planning and Control Mechanism for Intermittent

    System : -

    Organization of production planning and control operations in intermittent

    systems needs estimation of jobs, routing, scheduling, preparation of

    manufacturing orders, dispatching and production control.

    Here customer provides the blue print and other specification regarding the

    product to be manufactured. Then the organization formulates their

    production strategy to suit the needs of the customer.

    (i) This type of manufacturing system covers specialties of every type andsub assemblies or parts which are required to manufacture the product. Due

    to this there is continuous planning at each fresh order.

    (ii) Due to variety of orders and different lot sizes, the system needs wise

    and careful sequencing of operations which makes routing and scheduling

    operations elaborate and complex.

    (iii) Proper regulation and close inspection is required at different stages of

    production.

    (iv) Storage facilities are to be provided at each operational stage.So the job of stock control of raw materials, semi-finished goods and

    finished goods should be entrusted to competent personnel, who can regulate

    the operations and flow of material smoothly.

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    Intermittent systems can be further classified into two categories, namely

    (a) Project production

    Project production where a single assignment of complex nature is

    undertaken for completion within the given period and within the estimatedexpenditure.

    (b) Job production

    Jobbing production where one or few units of a product are produced to

    customers requirement within the given date amid within the price fixed

    prior to the contract.

    (c) Batch production

    Batch production where limited quantity of each type of product is

    authorized for manufacture at a time.

    CONTINUOUS SYSTEMIn this system the items are produced for the stocks and not for specific

    orders. Before planning manufacturing to stock, a sales forecast is made to

    estimate likely demand of the product and a master schedule is prepared to

    adjust the sales forecast according to past orders and level of inventory. Here

    the inputs are standardized and a standard set of processes and sequence of

    processes can be adopted. Due to this routing and scheduling for the wholeprocess can be standardized.

    After setting of master production schedule, a detailed planning is carried

    on. Basic manufacturing information and bills of material are recorded.

    Information for machine load charts, equipment, personnel and material

    needs is tabulated. In continuous manufacturing systems each production run

    manufactures in large lot sizes and the production process is carried on in a

    definite sequence of operations in a pre-determined order. In process storage

    is not necessary which in turn reduces material handling and transportation

    facilities. First in first out priority rules are followed in the system. In short,here the input-output characteristics are standardized allowing for

    standardization of operations and their sequence.

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    Production Control Mechanism for Continuous

    manufacturing system: -

    In this system the control mechanism is not as elaborate and complex as for

    intermittent system. In continuous system large quantities of standardized

    products are produced using standardized production process.

    Following points of control mechanism are worth noting for such a

    system

    (i) This system does not involve diverse work, due to which routing

    standardized route and schedule sheets are prepared.

    (ii) In case of standard products meant for mass production, master route

    sheets are prepared for more effective co- ordination of various departments.

    (iii) Scheduling is required to rate the output of various standard products in

    their order of priority, operations and correct sequence to meet sales,

    requirements.

    (iv) Work relating to dispatching and follow-up is usually simple. Dispatchschedules can be prepared well in advance in such systems. Continuous

    system can be divided into two types of production, namely

    (A) Mass & (B) Process production.

    Mass and flow production where a production run is conducted either on a

    single machine or on a number of machines, arranged according to the

    sequence of operations and several number of a product are manufactured at

    a time and stocked in warehouse awaiting sales.

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    INTERMITTENT PRODUCTIONSYSTEM

    PROJECT PRODUCTION

    Project production is characterized by complex sets of activities that must be

    performed in a particular order within the given period and within the

    estimated expenditure. Where output of a project is a product, such products

    are generally characterized by immobility during transformation. Operations

    of such products are carried out in fixed position assembly type of layout

    which can be observed in production of ships, locomotive and aircraft,construction of roads, buildings, etc.

    Characteristics of Project Production : -

    (A) Definite beginning and definite end

    Each project has a definite beginning and a definite end.

    (B) Fixed position layout

    Where the output of a project is a product, such products are generally

    characterized by immobility during transformation. Operations on such

    products are carried out in fixed position assembly type of layout which

    can be observed in production of ships, locomotive, aircraft, construction of

    roads/ buildings, etc.

    (C) High cost overrunsOften delays take place in the completion of the projects. Such delays are

    generally very expensive due to escalation in the cost of factors of

    production and incident of penalties.

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    (D) Personnel problems

    Project production has many personnel related problems namely:

    When there is a fast build up, staff is either borrowed from other

    departments or hired for short duration. Therefore, personnel involved in the

    project have limited (or short lived) interest in the project.

    Since each project has a limited duration, the staff starts spending more

    time forgetting prepared for the next project.

    Site for the project may be in the underdeveloped region and it may change

    from project to project which causes dislocation of the normal life.

    Importance of Project Production: -

    (A) Non -uniform requirement of resources

    Requirement of resources for project production is not uniform. At the end

    of the project, resources from the project are redeployed elsewhere in other

    projects. Even during the life of the project, requirement of resources is not

    uniform. Generally resource requirement (men, materials, money, etc.) in the

    beginning of the project is low which builds up fast with the progress of the

    project as more and more resources are absorbed, and then it levels off until

    there is gradual cutback as the project approaches completion.

    (B) Involvement of different agencies

    A project generally involves many tasks, each having its own specialization

    to be performed by different agencies. The tasks generally have strict

    precedence (i.e. certain tasks must be completed before the next begins)

    amid as such co-ordination between agencies is of utmost importance.

    (C) Scheduling and controlBecause of large number of activities, involvement of different agencies and

    strict precedence requirements, scheduling and control assumes great

    importance. Some network planning techniques like PERT and CPM have

    been found to be very useful to overcome the problems mentioned above.

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    JOB PRODUCTION

    Jobbing production is characterized by the manufacture of one or few

    numbers of a single product designed and manufactured strictly tocustomers specifications, within, the given period and wit/tin the price fixed

    prior to tile contract. Some typical examples of industries engaged in

    jobbing production are: general repair shops; special purpose machine tool

    manufacturers; workshops to manufacture jigs and fixtures for other units;

    building contractors; tailoring shops manufacturing made-to-measure suite

    of clothes; manufacturers of ships, cranes, furnaces, turbo-generators,

    pressure vessels; and others manufacturing articles made to customers

    orders.

    Characteristics of Job production

    (A) Disproportionate manufacturing cycle time

    A considerable amount of pre-planning and organization is necessary in such

    a venture. Relatively long delays occur at the assembly as well as at the

    materials processing stages due to lack of materials or components,

    imbalanced work flow, design changes, design errors detected during

    manufacture, inaccurate work measurements, etc. which tend to lengthen the

    manufacturing cycle time. At times, tile time needed to design the productexceeds its manufacturing time.

    (B) Large work-in-progress

    The work-in-progress inventory in a jobbing production is generally very

    large as detailed scheduling and progress control in this type of production is

    economically infeasible. For various reasons, jobs get delayed causing

    temporary work shortages. To overcome work shortages and keep men and

    machines busy, more work is released to the shops which in turn increases

    work-in-progress.

    (C) Limited functions of production planning and control

    The success of jobbing production mainly depends on the ability of the

    engineer incharge of the contract.

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    (D) Materials are indented and purchased on receipt of orders unlike in batch

    or mass production where material requirements are planned well in

    advance.

    (E) Process planning activity is almost absent. Drawings and specifications

    are directly given to the supervisor who is expected to decide work methods,

    select optimum process, fix up machine tools to be used and estimate time

    required completing an operation.

    Importance of Job production: -

    (A) Small production runs

    Jobbing production is characterized by the manufacture of one or few pieces

    of a product at a time under a separate contract, the production is made

    strictly to customers specifications.

    (B) Discontinuous flow of materials

    The flow of materials and components between different stages of

    manufacture is highly discontinuous due to imbalance in operation wise

    work content.(C) General purpose machines and process layout

    Plant and equipment is designed or procured and arranged to obtain

    maximum flexibility. General purpose machines and handling equipments

    capable of performing variety of operations with minimum set-tip times are

    installed in lie of variety in products. Tile machines are arranged to give

    process layout - layout by function. Similar machines, capable of doing

    similar type of operations, are grouped together. Presses, for example are

    kept at one place; milling machines are placed at another place; drilling

    machines are kept at third place; and so on and so forth. Each group ofmachines is usually designated as a work centre or a section or a shop.

    The grouping of machines gives a lot of flexibility in loading and

    scheduling. Temporary machine breakdowns and operators absenteeism can

    be taken care of by shifting jobs to another machine or shifting operators

    from less important jobs to important jobs.

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    (D) Highly skilled labour

    The labor force is usually highly skilled-highly qualified trade apprentices

    who are expected to work from minimum instructions. Instructions

    regarding what to make are issued in the form of specifications while

    instructions as to how to manufacture are usually oral. The workmenbeing highly skilled are expected to work independently and display a great

    deal of initiative and judgment. They are required to set up their own

    machines and prepare their OW special tools or production aids in order to

    further the manufacture of a part or a assembly.

    (E) Highly competent knowledgeable supervision

    Highly competent general engineers are engaged as foreman in the base

    workshop and a group of site engineers, practical men, with thorough

    training, capable of taking independent charge of each contract are employed

    to work at site. Therefore, these engineers (supervisors) in a jobbingproduction are the reservoir of job knowledge. The supervisor besides being

    able administrator is expected to improvise and determine best work

    methods, determine tool requirements, select the best process and provide

    management with reliable estimates of labor and materials for specific

    orders. The span of control - the number of workmen to be supervised by a

    supervisor - is kept low because of technical nature of the job.

    (F) Simple Mechanism

    Tools control function is simple. Standard tools are stocked while special

    tools are either made on the shop floor by the operators or purchased on

    request from supervisor.

    (G) Decentralized Process

    The scheduling activity is more or less decentralized. A schedule is prepared

    to show the start and completion date of each major component of the

    product. Job tickets giving completion date of each component are raised

    and given to the shop. The activity of day to day scheduling is left to the

    individual shop supervisor.

    EXAMPLE OF JOB PRODUCTION SYSTEM

    Job production involves firms producing items that meet the specific

    requirements of the customer. Often these are one-off, unique items such as

    those made by an architect or wedding dressmaker. For an architect, each

    building or structure that he designs will be different and tailored to the

    needs of each individual client.

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    With job production, a single worker or group of workers handles the

    complete task. Jobs can be on a small-scale involving little or no technology.

    However, jobs can also be complex requiring lots of technology.

    With low technology jobs, production is simple and it is relatively easy to

    get hold of the skills and equipment required. Good examples of the job

    method include:

    Hairdressers

    Tailoring

    Painting and decorating

    Plumbing and heating repairs in the home

    High technology jobs are much more complex and difficult. These jobs need

    to be very well project-managed and require highly qualified and skilled

    workers. Examples of high technology / complex jobs include:

    Film production

    Large construction projects (e.g. the Millennium Dome)

    Installing new transport systems (e.g. trams in Sheffield and Manchester)

    ADVANTAGES

    The advantage of job production is that each item can be altered for the

    specific customer and this provides genuine marketing benefits. A business

    is likely to be able to add value to the products and possibly create a

    unique selling point (USP), both of which should enable it to sell at high

    prices.

    DISADVANTAGES

    Whether it is based on low or high technology, Job production is an

    expensive process as it is labour intensive (uses more workers compared to

    machines). This raises costs to firms as the payment of wages and salaries is

    more expensive than the costs of running machines.

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    BATCH PRODUCTION

    Batch production is characterized by the manufacture of a limited number of

    product (but many such, quantities of different products) produced at regularintervals and stocked in warehouses as finished goods (or finished parts,)

    awaiting sales (or withdrawal for assembly). Typical examples of batch

    production are : Process industries such as pharmaceuticals, paints,

    chemicals; medium and heavy engineering industry engaged in the

    manufacture of electric motors, switch gears, heavy motor vehicles, internal

    combustion engines; manufacturers of ready made garments; manufacturing

    and assembly shops such as machine tools; sub-contractors which take on

    machining of batches of components to the drawings of a large

    manufacturer.

    Batchproduction is used to produce or process any product in groups that

    are called batches, as opposed to a continuous production process, or a one-

    time production. An example of batch production can be found in a bakery.

    The products, for example bread, are made in batches of however many will

    fit in the baker's oven at a time. When that batch is made, the baker will start

    the process again with a new batch. Batch production techniques are used in

    the manufacture of specialty chemicals such as active pharmaceutical

    ingredients, inks, paints and adhesives.

    In the manufacture of inks and paints, a technique called a color-run is used.

    A color-run is where one manufactures the lightest color first, such as light

    yellow followed by the next increasingly darker color such as orange, then

    red and so on until reaching black and then they start over again. This

    minimizes the cleanup and reconfiguring of the machinery between each

    batch. White (by which is meant opaque paint, not transparent ink) is the

    only color that cannot be used in a color run due to the fact that a small

    amount of white pigment can adversely affect the medium colors.

    There are inefficiencies associated with batch production. The productionequipment must be stopped, re-configured, and its output tested before the

    next batch can be produced.

    Time between batches is known as 'Down Time' where the factory would

    make seasonal items or consumables such as toasters where no one can

    predict the quantity needed.

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    There are several advantages of batch production; it can reduce initial capital

    outlay because a single production line can be used to produce several

    products. As shown in the example, batch production can be useful for small

    businesses who cannot afford to run continuous production lines. Also,

    companies can use batch production as a trial run. If a retailer buys a batch

    of a product and people do not buy them then the producer can cease

    production without having to sustain huge losses. Other types of production

    include: assembly line, job production, continuous, cell, and project.

    Characteristics of batch production: -

    (A) Supervisor to possess knowledge of a specific process

    The supervisors have considerable knowledge of a specific process.

    Supervisor in the grinding section for example, may not know about turning

    and drilling work but is expected to P055C55 a fund of knowledge of

    different types of grinding operations. Similarly, a supervisor in the gear

    shop is expected to have sound knowledge in working of different types of

    gear cutting machines.

    (B) General purpose machines and process type of layout

    Plant and equipment is procured and arranged to obtain maximum

    flexibility. General purpose machines and handling equipments capable of

    performing variety of operations with minimum set-lip tunes are installed in

    lieu of variety of products. The machines are arranged to give processlayout- layout by function. Similar machines capable of doing similar types

    of operations are grouped together and kept at one place. Presses, for

    example, are put together and kept at one place, milling machines are placed

    together at another place, drilling machines are kept at the third place, and

    gear cutting machines are located at the fourth place and so on. Each group

    of machines is usually designated as a work centre or a section or a shop.

    (C) Manual materials handling:

    Materials handling in batch production as compared to jobbing production

    are small. Individual components and parts arc placed in trolleys or in binsand are transported as unit loads. Materials handling may be mechanized by

    deploying power driven trucks.

    (D) Manufacturing cycle time affected due to queues

    The manufacturing cycle time is comparatively smaller than jobbing

    production but is much more than mass and flow production. The batches of

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    work tend to queue up at different machines due to differing cycle times,

    batch sizes and sequence of operations.

    (E) Large work-in-progress

    Work in progress is comparatively large due to varying work content of

    different components, imbalances in manufacturing times, formation ofqueues between the machines.

    (F) Need to have production planning and control

    Functions of production planning and control in a batch production unit are

    more complex than those in jobbing production or mass and flow

    production.

    Materials control and tools control functions are important. Scientific

    stock-control system needs to be used to ensure routine replenishment.

    Detailed operational layouts and route sheets are prepared for each part ofthe product.

    Lo and scheduling needs to be more detailed and more sophisticated since

    every machine requires to be individually scheduled.

    Progressing function is very important to collect information on progress

    of work.

    A separate progress card needs to be maintained to record progress of each

    component.

    Expediting is generally necessary since quite often jobs, due to imbalances

    in work content, tend to lag behind.

    Importance of Job production: -

    (A) Short runs

    Batch production is also characterized by short production runs and frequent

    changes of set up. The equipment and the assembly set up is used for a

    limited number of parts or assemblies and is then changed to make. adifferent product. The production is generally made to stock.

    (B) Skilled labor in specific trades

    The labor force is expected to possess skill in one specific manufacturing

    process turning, milling, drilling, welding, grinding, hobbing, filling etc.

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    Simpler machine set-ups may be performed by the operator but those

    involving complex operations arc set by the separate machine setter.

    (C) Limited span of control

    The amount of supervision required in batch production is lower than that of

    jobbing production and is dependent of the batch size. The ratio of directworkmen to supervisors is more or less a function of batch size. The smaller

    the batches, the lower are the ratio of direct workers to supervisors, and vice-

    versa. This is because smaller lots require each supervisor to spend a great

    deal of their time in allocating new work, giving instructions, follow up n

    the shop floor for proper movement of materials from and to the machines,

    identifying delays and interruptions, and arranging, in consultation with

    planning, work load in his section to keep his men busy.

    (D) Flexibility of production schedules

    Disruptions due to machine breakdowns or absenteeism do not seriously

    affect production as another machine can be used or another operator from

    another machine can be shifted.

    EXAMPLE OF BATCH PRODUCTION SYSTEM

    As businesses grow and production volumes increase, the production

    process is often changed to a batch method. Batch methods require that a

    group of items move through the production process together, a stage at a

    time.

    For example when a bakery bakes loaves of wholemeal bread, a large ball of

    wholemeal dough will be split into several loaves which will be spread out

    together on a large baking tray. The loaves on the tray will then together be

    cooked, wrapped and dispatched to shelves, before the bakery starts on a

    separate batch of, for example, crusty white bread. Note that each loaf is

    identical within a batch but that loaves can vary from batch to batch.

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    CONTINUOUS PRODUCTIONSYSTEM

    MASS PRODUCTIONStandardization is the fundamental characteristic of this system. Here items

    are produced in large quantities and much emphasis is not given to

    consumers orders. In fact the production is to stock and not to order.

    Standardization is there w.r.t. materials and machines. Uniform and

    uninterrupted flow of material is maintained through pre determined

    sequence of operations required to produce the product. The system can

    produce only one type of product at one time.

    These days, mass production system is generally used to manufacture sub-

    assemblies or particular parts/components of an item. These parts are

    assembled together by the enterprise to get the final product. One distinct

    advantage of this approach is that different combinations of sub-assemblies

    or parts can be used to manufacture different kinds of products.

    Specialization and standardization in manufacturing single component also

    leads to economies in production and product diversification to meet specific

    demands of consumers.

    Mass production is the name given to the method of producing goods inlarge quantities at low cost per unit. But mass production, although allowing

    lower prices, does not have to mean low-quality production. Instead, mass-

    produced goods are standardized by means of precision-manufactured,

    interchangeable parts. The mass production process itself is characterized by

    mechanization to achieve high volume, elaborate organization of materials

    flow through various stages of manufacturing, careful supervision of quality

    standards, and minute division of labour. To make it worthwhile, mass

    production requires mass consumption. Until relatively recent times the only

    large-scale demand for standardized, uniform products came from military

    organizations. The major experiments that eventually led to mass production

    were first performed under the aegis of the military.

    Machine tools and interchangeable parts The material basis formass production was laid by the development of the machine-tool industry--

    that is, the making of machines to make machines. Though some basic

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    devices such as the woodworking lathe had existed for centuries, their

    translation into industrial machine tools capable of cutting and shaping hard

    metals to precise tolerances was brought about by a series of 19th-century

    innovators, first in Britain and later in the United States. With precision

    equipment, large numbers of identical parts could be produced at low cost

    and with a small work force.

    The system of manufacture involving production of many identical parts and

    their assembly into finished products came to be called the American

    System, because it achieved its fullest maturity in the United States.

    Although Eli Whitney has been given credit for this development, his ideas

    had appeared earlier in Sweden, France, and Britain and were being

    practiced in arms factories in the United States. During the years 1802-08,

    for example, the French migr engineer Marc Brunel, while working for the

    British Admiralty in the Portsmouth Dockyard, devised a process forproducing wooden pulley blocks by sequential machine operations. Ten

    men, in place of 110 needed previously, were able to make 160,000 pulley

    blocks per year. British manufacturers, however, ignored Brunel's ideas, and

    it was not until London's Crystal Palace exhibition of 1851 that British

    engineers, viewing exhibits of machines used in the United States to produce

    interchangeable parts, began to apply the system. By the third quarter of the

    19th century, the American System was employed in making small arms,

    clocks, textile machinery, sewing machines, and a host of other industrial

    products.

    The assembly line.Though prototypes of the assembly line can be tracedto antiquity, the true ancestor of this industrial technique was the 19th-

    century meat-packing industry in Cincinnati, Ohio, and in Chicago, where

    overhead trolleys were employed to convey carcasses from worker to

    worker. When these trolleys were connected with chains and power was

    used to move the carcasses past the workers at a steady pace, they formed a

    true assembly line (or in effect a "disassembly" line in the case of meat

    cutters). Stationary workers concentrated on one task, performing it at a pace

    dictated by the machine, minimizing unnecessary movement, anddramatically increasing productivity.

    Drawing upon observations of the meat-packing industry, the American

    automobile manufacturer Henry Ford designed an assembly line that began

    operation in 1913. The result was a remarkable reduction of manufacturing

    time for magneto flywheels from 20 minutes to five minutes. This success

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    stimulated Ford to apply the technique to chassis assembly. Under the old

    system, by which parts were carried to a stationary assembly point, 12 1/2

    man-hours were required for each chassis. Using a rope to pull the chassis

    past stockpiles of components, Ford cut labour time to six man-hours. With

    improvements--a chain drive to power assembly-line movement, stationary

    locations for the workmen, and work stations designed for convenience and

    comfort--assembly time fell to 93 man-minutes by the end of April 1914.

    Ford's methods drastically reduced the price of a private automobile,

    bringing it within the reach of the common man. (see also Index: automotive

    industry ) Ford's spectacular feats forced both his competitors and his parts

    suppliers to initiate his technique, and the assembly line spread through a

    large part of U.S. industry, bringing dramatic gains in productivity and

    causing skilled workers to be replaced with low-cost unskilled labour.

    Because the pace of the assembly line was dictated by machines, the

    temptation arose to accelerate the machines, forcing the workers to keep up.Such speedups became a serious point of contention between labour and

    management, while the dull, repetitive nature of many assembly-line jobs

    bored employees, reducing their output.

    Effects on the organization of work. The development of massproduction transformed the organization of work in three important ways.

    First, tasks were minutely subdivided and performed by unskilled workers,

    or at least semiskilled workers, since much of the skill was built into the

    machine. Second, manufacturing concerns grew to such size that a largehierarchy of supervisors and managers became necessary. Third, the

    increasing complexity of operations required employment of a large

    management staff of accountants, engineers, chemists, and, later, social

    psychologists, in addition to a large distribution and sales force. Mass

    production also heightened the trend toward an international division of

    labour. The huge new factories often needed raw materials from abroad,

    while saturation of national markets led to a search for customers overseas.

    Thus, some countries became exporters of raw materials and importers of

    finished goods, while others did the reverse.

    In the 1970s and '80s some countries, particularly in Asia and South

    America, that had hitherto been largely agricultural and that had imported

    manufactured goods began industrializing. The skills needed by workers on

    assembly-line tasks were easily acquired, and standards of living in these

    developing countries were so low that wages could be kept below those of

    the already industrialized nations. Many large manufacturers in the United

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    States and elsewhere therefore began "outsourcing"--that is, having parts

    made or whole products assembled in developing nations. Consequently,

    those countries are rapidly becoming integrated into the world economic

    community.

    Mass production (also called flow production orrepetitive flow

    production) is the production of large amounts of standardized products on

    production lines. It was popularised by Henry Ford in the early 20th

    Century, notably in his Ford Model T. Mass production is notable because it

    permits very high rates of production per worker and therefore provides very

    inexpensive products. Mass production is capital intensive, as it uses a high

    proportion of machinery in relation to workers. With fewer labour costs and

    a faster rate of production, capital is increased while expenditure isdecreased. However the machinery that is needed to set up a mass

    production line is so expensive that there must be some assurance that the

    product is to be successful so the company can get a return on its

    investment. Machinery for mass production such as robots and machine

    presses have high installation costs.

    One of the descriptions of mass production is that the craftsmanship is in the

    workbench itself, not the training of the worker; rather than having a skilled

    worker measure every dimension of each part of the product against the

    plans or the other parts as it is being formed, there are jigs and gauge blocksthat are ready at hand to ensure that the part is made to fit this set-up. It has

    already been checked that the finished part will be to specifications to fit all

    the other finished parts - and it will be made quicker, with no time spent on

    finishing the parts to fit one another. This is the specialized capital required

    for mass production; each workbench is different and each set of tools at

    each workbench limited to those necessary to make one part.

    Use of assembly lines in mass production

    Mass production systems are usually organized into assembly lines. The

    assemblies pass by on a conveyor, or if they are heavy, hung from an

    overhead monorail.

    In a factory for a complex product, rather than one assembly line, there may

    be many auxiliary assembly lines feeding sub-assemblies (i.e. car engines or

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    seats) to a backbone "main" assembly line. A diagram of a typical mass-

    production factory looks more like the skeleton of a fish than a single line.

    This is also used in food manufacturer to produce foods continuously.

    Characteristics of mass & flow production

    (A) Special purpose machines and product type layout:

    Special purpose machines are used and the plant assembly stages are laid out

    on the basis of product layout, the layout-by-sequence.

    (B) Lesser flexibility in production schedules

    Interruptions due to breakdowns and absenteeism seriously affect production

    as stoppage of one machine usually disturbs the working of other machines.Systematic maintenance and provisioning of stand-by operators are,

    therefore, two major management functions.

    Importance of Job production: -

    (A) Continuous flow of material

    The flow of materials is continuous and there is little or no queuing at any

    stage of processing.(B) Mechanized materials handling

    Materials handling is comparatively less firstly because materials move

    through a short distance between stages and secondly the materials handling

    activity is mostly mechanized by conveyors and transfer machines.

    (C) Low skilled labor

    Relatively low skilled labor is employed.

    (D) Short manufacturing cycle time

    The manufacturing cycle time is very short. The machine capacities are

    balanced by duplicating machines wherever necessary.

    (E) Easy supervision

    Supervision is relatively easier as only few instructions are necessary and

    that too at the start of the job.

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    (F) Limited work- in- progress

    Work-in-progress is comparatively less since the manufacturing line is

    balanced.

    EXAMPLE OF MASS PRODUCTION SYSTEMFlow production involves a continuous movement of items through the

    production process. This means that when one task is finished the next task

    must start immediately. Therefore, the time taken on each task must be the

    same.

    Flow production (often known as mass production) involves the use of

    production lines such as in a car manufacturer where doors, engines, bonnets

    and wheels are added to a chassis as it moves along the assembly line. It is

    appropriate when firms are looking to produce a high volume of similaritems. Some of the big brand names that have consistently high demand are

    most suitable for this type of production:

    Heinz baked beans

    Kelloggs corn flakes

    Mars Bars

    Ford cars

    ADVANTAGES

    Flow production is capital intensive. This means it uses a high proportion of

    machinery in relation to workers, as is the case on an assembly line. The

    advantage of this is that a high number of products can roll off assembly

    lines at very low cost. This is because production can continue at night and

    over weekends and also firms can benefit from economies of scale, which

    should lower the cost per unit of production.

    DISADVANTAGES

    The main disadvantage is that with so much machinery it is very difficult to

    alter the production process. This makes production inflexible and means

    that all products have to be very similar or standardized and cannot be

    tailored to individual tastes. However some variety can be achieved by

    applying different finishes decorations etc at the end of the production line.

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    PROCESS PRODUCTION

    Process production is characterized by tile manufacture of a single product

    produced and stocked in the warehouses awaiting sales. The flexibility of

    such plants is almost zero as only one type of product can be produced in

    such plants. Typical examples of such plants are sugar, steel, cement, paper,

    coke, refineries, etc.

    Characteristics of process production: -

    (A)Special purpose machines with built-in controls

    The layout of plant, shape and size of its buildings, location of services and

    storage yards, position of cranes and conveyors is such that material flow is

    unidirectional and at the steady rate. Special purpose machinery and

    equipment with built-in controls to measure output and regulate input are

    employed to suit the needs.

    (B) Highly mechanized materials handling

    Materials handling is highly mechanized. Conveyor system and automatic

    transfer machines move materials from one stage to another.

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    JUST-IN-TIME PRODUCTION SYSTEM

    (JIT)

    Introduction: Just in Time manufacturing is a systems approach todeveloping and operating a manufacturing system. It is based on the total

    elimination of waste. JIT is not a new concept. It has been part and parcel of

    the Japanese manufacturing industry adopted approach for quite some time.

    It requires that equipment, resources and labor are made available only in the

    amount required and at the time required to do the job. It is based on

    producing only the necessary units in the necessary quantities at the

    necessary time by bringing production rates exactly in line with market

    demand. In short, JIT means making what the market wants, when it wants

    it. JIT has been found to be so effective that it increases productivity, workperformance and product quality, while saving costs.

    Critical Elements in JIT manufacturing

    Partnerships

    Commitments

    Contracts Supporting Partnerships

    Developing JIT Suppliers

    Partnerships - A Mutually Beneficial System

    Customer-Supplier proximity

    Partnerships

    In the past companies were capable of remaining independent and

    competitive when they had the capability and resources necessary to produce

    a product. This is no longer possible. As technology increases in complexity,

    companies overcome capital limitations or labor intensive requirements by

    becoming dependent on suppliers to provide services. Many services and

    Original Equipment Manufacturing (OEM) suppliers have evolved as theresult. Companies now appreciate that long-term success relies on the

    quality of the customer-supplier relationship established so that they will

    develop successful partnerships. Hence, successful partnerships require the

    development of mutually beneficial programs.

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    Contracts Supporting Partnerships

    By ensuring fair and equitable contracts, many of the problems in

    developing customer-supplier relationships are overcome by JIT

    manufacturers. The goal ofJIT is to make long-term contracts withsuppliers. Long-term contracts usually extend for one or more years and can

    consist of one or more part requirements

    Integrated Process Control (IPC)

    In most cases, the typical goals of manufacturing consist of meeting

    production schedules, cost projections, and product specifications. However,

    two key points are usually overlooked: optimizing the production process

    and meeting customer requirements concurrently. The company must be

    aware of changes in requirements and continually improve the productionprocess. Integrated Process Control (IPC) achieves the goals ofJIT

    manufacturing by optimizing production to meet both manufacturer and

    customer requirements. In IPC, two concepts control the process of

    continual improvement.

    Goals

    Secure a steady flow of quality parts.

    Reduce the lead time required for ordering product.

    Reduce the amount of inventory in the supply and production pipe lines.Reduce the cost of purchased material.

    Objectives

    Improve purchasing efficiency.

    Improve quality and delivery performance of suppliers.

    Isolate factors that influence the cost of material.

    Remove unnecessary cost factors in the materials supply system.

    Tactics

    Regard suppliers as an extension of the internal manufacturing process and

    cultivate them as long term business partners.

    Establish long term purchasing and supply commitments.

    Improve communication with suppliers.

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    Involve suppliers in early stages of new product planning.

    Use supplier expertise to improve design manufacturability and reduce

    product cost.

    Quality for JITQuality is an integral part of a JIT program. Quality control concentrates on

    quality at every stage of manufacture including the purchase of raw material.

    To increase the supplier quality two methods are used in a JIT system;

    supplier quality engineering (SQE) and receiving inspection (RI).

    Supplier quality engineering is used to evaluate supplier capability, help

    suppliers develop process control, resolve quality issues with suppliers, and

    certify that suppliers qualify forJIT production. Receiving inspection

    provides an inspection service for purchasing.

    Planning the production process

    A valuable tool in planning the production process is to isolate and define

    the elements that make up a production system as building blocks.

    Performance measures

    To achieve continued improvement, a company must measure the

    performance levels of its smallest processes against its optimum values. This

    is accomplished by having performance measures visible to all levels in acompany. The use of control charts is one of the best ways to show the

    collected performance measures.

    Conclusion

    Hence we can see that to have a Total JIT manufacturing system, a

    company-wide commitment, proper materials, quality, people and

    equipments must always be made available when needed. In addition; the

    policies and procedures developed for an internal JIT structure should also

    be extended into the company's supplier and customer base to establish the

    identification of duplication of effort and performance feedback review to

    continuously reduced wastage and improve quality. In general, it can be said

    that there is no such thing as a KEY in achieving a JIT success; only a

    LADDER; where a series of continuous steps of dedication in doing the job

    right every time is all it takes.


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