BALAJI INSTITUTE OF I.T AND MANAGEMENT KADAPA MERGED PDF -LAST-2.5 UNITS.pdf · Modern Production/Operations Management, Elwood S.Buffa and Rakesh K Sarin, Wiley ... Production and

BALAJI INSTITUTE OF

I.T AND MANAGEMENT

KADAPA

OPERATIONS MANAGEMENT

ICET CODE: BIMK SECOND INTERNAL

ALSO DOWLOAD AT http://www.bimkadapa.in/materials.html

Name of the Faculty: V SREERAM YASHASVEE

Units covered: Half of 3rd Unit, 4th & 5th units

E-Mail: [email protected]

SEMESTER-II OPERATIONS MANAGEMENT

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UNIT - 3 SCHEDULING BALAJI INSTITUTE OF IT & MANAGEMENT

(17E00206) OPERATIONS MANAGEMENT

The objective of the course is to enable students to understand the production Planning and

Controlling aspects of a typical production and operations organization. Study understands

the concepts of work study and Quality management.

1. Introduction: Overview of production and Operations Management(POM) Function,

Historical Development of POM, POM scenario Today, product and process Design Product

and Process Development, Manufacturing Process Technology, CAD/CAM analysis

2. Facilities Management & Aggregate Planning: Location of Facilities, Layout of

Facilities, Optimization of Product/ Process Layout, Flexible Manufacturing and Group

Technology: Aggregate Planning – Preparation of Aggregate Demand Forecast, specification

of Organizational Policies For Something, Capacity Utilization, Determination of feasible

Production Alternatives.

3. Scheduling: Scheduling In Job, Shop Type Production, Shop- Loading, Assignment and

Sequencing, Scheduling In Mass, Line of Balance, Methods Production Control, World Class

Production.

4. Work Study and Quality Management: Method Study, Work Measurement, Work

Design, Job Design, Work Sampling, Industrial Engineering Techniques. Economics of

Quality Assurance Inspection and Quality Control, Acceptance Sampling, Theory of Control

Charts, Control Charts for Variables and Control Charts for attributes.

5. Materials Management: Introduction, Objectives, Importance of Materials management -

Issues in Materials Management - Functions - Activities - Selection of Materials -

Advantages of Materials Management.

Text Books:

Production and Operations Management, Aswathappa K - Himalaya Publishing

House

"Production and Operations Management" - Dr. K.Sai Kumar, Kalyani Publishers

References:

Operations Management and Control, Biswajit Banarjee - S.Chand

Production and Operations Management - Dr.K.C.Arora, 2nd Edition - University

Science Press

Production and Operations Management, R.Panneerselvam: PHI Learning Private

Ltd.

Production Management, Martand T Telsang - S Chand

Modern Production/Operations Management, Elwood S.Buffa and Rakesh K Sarin,

Wiley ...

Production and Operations Management, SN Chary, Tata McGraw Hill, New Delhi

Operations Management, Mahadevan, Pearson Education, New Delhi

Production and Operations Management - Text and Cases, Upendra Kachru, Excel

Books


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4. SCHEDULING IN MASS, CONTINUOUS AND PROJECT

TYPE PRODUCTION:

4.1. INTRODUCTION:

Production scheduling requires short term production planning i.e. planning on

a day to day or week to week basis planning for such short time intervals is not

required in production system such as the continuous production system or the

mass production system or large batch production.

4.2. SCHEDULING IN CONTINUOUS PRODUCTION SYSTEM:

Continuous or repetitive manufacturing is characterized by long production runs

of identical or similar discrete items through the same sequences of

operation/processing steps. The production facilities are located on adjacent to

another production facilities are located on adjacent to another as per the

sequence of operation/processing steps for an item in order to reduce the

material handling distance and cost such arrangements are referred to as

production lines or assembly lines and manufacturing shops are called as flow

shops.

Several approaches that right volume repetitive manufacturing operations can be

used to meet the demand for varying volumes and product mixes are,

To have separate production facilities for each product and to vary the

production rate in response to the demand pattern. But this would require

a high investment in various facilities that would seldom be fully utilized.

To run one large facility on a product for a while and then change to

another product for a while. In this case, the rescheduling and

coordinating problems could be significant.

To stabilize the product mix and the production rate for an extended

period so that many of the advantages of just in time production can be

achieved.

4.3. CONTROLLING CONTINUOUS PRODUCTION:

The major problem in flow shop production control flow chart is to attain the

desired production rate with maximum possible efficiency i.e. max possible

utilization of resources. For this it is necessary to determine the techniques

process steps sequence of operations the required capacity of assembly lines the


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number of personal and the amount of work per person working on the

assembly line.

The speed of the assembly line is controlled by the required output rate the

distance between successive work stations. The technique used in such a

production situation where it is necessary to nearly equally divide the work to

be done among the workers so that the total number of employees required on

the assembly line is minimized is known as line of balancing technique.

5. LINE OF BALANCE (LOB):

LOB is a simple graphical technique which can be used in project planning

scheduling and progress tracking to depict time quantity relation. This method

was developed by the U.S navy during world war-2. It is most appropriate for

assembly operation involving a number of distinct components.

LOB technique can be regarded as a slightly more sophisticated form the Gantt

chart the objective being to study the progress of jobs at regular integrals, to

compare progress on each operation with the progress necessary to satisfy the

eventual delivery requirements and to identify those operations in which

progress in unsatisfactory.

5.1. OBJECTIVES OF LINE OF BALANCE:

To study the progress of jobs at regular intervals and

To compare the actual progress with that required to satisfy delivery

requirements and

To identify those operations in which progress is unsatisfactory.

5.2 . LINE OF BALANCE TECHNIQUE:

LOB technique consists of five main stages all utilizing graphic aids.

A graphical representation of the delivery objective

A chart of the production program showing the sequence and duration of

all activities required to produce a product.

A progress chart of the current status of component completion

A line of balance drawn to show the relationship of component progress

to the output needed to meet the delivery schedule

Analyze of progress


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1. OBJECTIVE CHART

The objective chart shows the expected schedule of production i.e.

scheduled deliveries and the actual completion rate i.e. actual deliveries

made by a date.

A dip in the actual deliveries line below the scheduled delivery line is an

obvious cause for alarm.

2. PROGRAM PLAN: a chart of the operations required to complete one

unit of the finished product is called the program plan. In program plan

various operations involved in the production process are reviewed and

listed along with lead times. A specimen of program plan is shown in the

below figure.

3. PROGRESS CHART: Progress chart shows the number of items finished

at each of the critical or important operations at a given time. Let us assume

that the review data is week no. of figure by which according to objective

chart so items must have passed the last operation-2 figure of the program

plan. The number of items that have completed this and each of the other

operations can be obtained simple by checking inventory levels.

4. LINE OF BALANCE: the line of balance can be constructed analytically or

graphically. The LOB shows the total number of items which should have

been completed at each operations.

6. SCHEDULING IN PROJECT TYPE PRODUCTION:

Project scheduling is an important aspect of project management and control

and ensures timely implementation of project. It establishes times and

sequences of the various phases of the project. In project scheduling the project

manager considers the various activities of overall projects and the tasks that

must be accomplished and relates them coherently to one another over the

projects time horizon.

Project networks can be used to plan record and document a schedule and to

track actual result against the schedule. By analysis a network which planning

scheduling and control of a project becomes much easier network provides a

comprehensive study of the entire project in terms of precedence and succession

of various activities as well as the resource available to perform the activities

with an object to evolve some better and quicker plan to complete the work.


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6.1. PROGRAMME EVALUATION AND REVIEW TECHNIQUES

(PERT):

The program or project evaluation and review techniques commonly

abbreviated PERT is a model for management designed to analyze and represent

the tasks involved in completing a given projects it was developed primarily to

simplify the planning and scheduling of large and complex projects. It was able

to incorporate uncertainly by making it possible to schedule a project while not

knowingly precisely the details and durations of all the activities. It is more of

an event oriented technique rather than start and completion oriented and is used

more in R & D type projects where time rather than costs is the major factor. It

is intended for very large scale, one time complex non routine projects.

According to the originators of the PERT any given activity delineated in a

network is unlikely to be completed on time. Sometimes all aspects of a job

may be easier to complete than expected while job may be easier to complete

than expected while at other time unexpected snags may occur causing up-

planed delays. This method uses three time estimates for an activity rather than

a single estimate. They are,

1. OPTIMISTIC TIME (a): this is the shortest time the activity can take to

complete. There is more than one chance in a hundred of completing the

activity in this amount of time it represents an ideal estimate.

2. MOST LIKELY TIME (m): This refers to be expected to occur most

often if the activity were frequently repeated under exactly the same

conditions. It is the model time.

3. PESSIMISTIC TIME (b): This is the longest time the activity could

take to finish. It is the worst time estimate and represents the time the

activity would take if bad luck was faced it occurs with a profanity of less

than one percent.

FEATURES OF PERT:

Draw the network for the project

Three time estimates namely optimistic normal and pessimistic times are

estimated for each activity to take into account the presence of

uncertainties

The three time estimates are used to calculate the expected time for each

activity.


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Critical path and slack time are computed. The sequence of activities

which has maximum expected time for the completion of the project

determines the critical path.

The three time estimates are provided by a person who is in charge of the

operation and the values are generally based on the judgment and

experience.

The time estimates are assumed to follow a beta distribution.

STEPS IN PERT

The steps in PERT are as follows

1. DRAWING THE PERT NETWORK: once the activities have all been

specified and management has decided which activities must precede

others the networks can be drawn.

There are two common techniques for drawing PERT networks.

The first is called activity on node (AON) because the nodes represent the

activities.

The second is called activity on are (AOA) because the arcs are used to

represent the activities.

The AON techniques are easier and are often used in commercial software.

2. ACTIVITY TIMES: The next step in the PERT procedure is to assign

estimates of the time required to complete each activity. Time is usually

given in units of weeks. For one of a kind projects or for new jobs

providing activity time estimates is not always an easy task without solid

historical data, managers are often uncertain as to activity times for this

reason the developers of PERT employed a probability distributing based

on three time estimates for each activity.

a. Optimistic time (a)

b. Most likely time (m)

c. Pessimistic time (b)

3. IDENTIFYING CRITICAL PATH: Once the expected completion

time for each activity has been determined we accept it as the actual time

of the task. We now proceed to calculation of the whole time required for

the completion of the whole project. In order to arrive at the duration of

the project we have to analyze the network and determine what is known

as its critical path. A path is a set of continuous series of activities


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through the network that lead from the initial node of the network to its

terminal node. The critical path is the longest time path route through the

network.

4. PROBABILITY OF COMPLETING THE PROJECT WITH IN

GIVEN TIME: In order to calculate the probability of completing the

project within given time the standard deviation of each activity is known

with the help of below equation.

Ts – Te

Z =

6.3. CRITICAL PATH METHODS (CPM): critical path method is another

techniques closely allied to PERT. The methodology of CPM and PERT are to a

large extent similar although two techniques are developed independent of each

other and their objective are by the large different CPM is applied where the

activity times are more or less certain e.g. projects of recurring nature

construction of building or highways planning and launching of new products

scheduling ship construction and repairs etc.

ASSUMPTIONS OF CPM

The assumption behind the CPM analysis is as follows.

Project activities can be identified as entities (there is a clear beginning

and ending point for each activity)

Project activity sequence relationships can be specified and networked

Project control should focus not h critical path

The activity time estimates when using the three line approach follow the

beta distribution the variance of the project assumed to equal the sum of

the variance along the critical path.

FEATURES OF CPM

The features of CPM are as follows

1. DIAGRAM: A central feature of the CPM is the use of a diagram to

highlight the many elements of projects and how they are tied together

this model develops the multifaceted project into a kind of network. The

diagram identifies different possible paths a project can take.


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2. CRITICAL PATH: The critical path that gives CPM is name refers to

the potential path to completion of a project that the CPM diagrams

shows would take the longest. In other words a critical path for a project

is the series of activities that determines the earliest time by which the

project can be completed and the longest path through the network

diagram which has the least amount of slack time.

3. ADJUSTMENTS: Project managers using CPM can updates the diagram

for the project as individual activities occur allowing managers to swiftly

note the impact of the projects progress or lack of progress and to

calculate accordingly this is a way of recognize the ripple effect that the

delay in one activity can create and to work to keep the project on

schedule and at the expected cost. It is also possible that the diagram will

evolve as each activity is completed and a new critical path emerges

alerting decisions on sequence and other areas.

VARIOUS TIMES USED IN CPM

To find the critical path, we need to determine the following quantities for

each activity in the network.

1. EARLIEST START TIMES (ES): The earliest time an activity can

begin without violation of immediate predecessor requirements. It is the

earliest possible time at which an activity can start and is calculated by

moving from first to last event in the network diagram.

2. EARLIEST FINISH TIME (EF): The earliest timeout which an activity

can end

Earliest finish time: Earliest start time + duration of activity

3. LATEST START TIME (LS): The latest time an activity can begin

without delaying the entire project. Latest start time: Latest finish time –

duration of the activity

4. LATEST FINISH TIME (LF): the latest time can activity can end

without delaying the entire project. It is calculated by moving backward

i.e. from last event to first event of the network diagram.


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ADVANTAGES OF CPM

It provides an analytical approach to the achievement of project

objectives which are defend clearly

It identifies most critical element and pays more attention to these

activities

It provides a standard method for communicating project plan schedules

and cost.

Thus a CPM technique is a very useful analysis in production planning of

a very large project.

DIFFERENCES BETWEEN PERT AND CPM

Basis of difference PERT Critical path CPM

method

Meaning PERT is appropriate

where time estimates are

uncertain in the duration

of activities measured by

optimistic time, most

likely time and

pessimistic time.

CPM is good when time

estimates are found with

certainty CPM assumes

that the duration of every

activity is constantan

therefore every activity

is critical or not.

Nature PERT is concerned with

events which are the

beginning or ending

points of operations

CPM is concerned with

activities

Suitability PERT is suitable for non

repetitive projects

CPM is designed for

repetitive projects

Analyzed PERT can be analyzed

statistically

CPM cannot be analyzed

statistically

Relationship between

time and cost

PERT is not concerned

with the relationship

between time and cost

CPM establishes a

relationship between

time and cost and cost is

proportionate to time


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7. PRODUCTION CONTROL:

Production control involves implementation of production plans or schedules by

coordinating different activities. It seeks to ensure that production operations

and actual performance occur according to planned operations and performance

According to BETHED WALTER smith and stockman production control is

essentially the control of quantity in manufacturing

7.1 .OBJECTIVES OF PRODUCTION CONTROL

An enterprise wishes to obtain the following objectives through production

control

Making necessary arrangements for the production of goods and services

according to the predetermined demand.

Arranging necessary raw materials machines, equipments tools and

workers for production.

Maintaining the inventory of raw materials at the optimum level which

requires the minimum capital investment and the least production

obstacles.

Utilizing the production facilities building plants men materials etc to its

maximum so that he production cost may be kept minimum and goods

and services are made available as and when they are required.

To arrange for product development and design

To arrange the activities of quality control and inspection so that the

goods may be produced according to the pre determined specifications

and standards.

Determining economic lots and to ascertain sequence of operations so

that set up cost is reduced.

Evaluating the route of production and the proper production progress

from time to time and to arrange for its proper guidance and control

7.2. FACTORS INFLUENCING PRODUCTION CONTROL

The factors that influence production control are as follows.

1. NATURE OF PRODUCTION: In job oriented manufacturing products

and operations are designed for some particular order which may or may

not be repeated in future. Here production usually requires more time


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whereas in a continuous manufacturing system inventory problems are

more complex but control operations are rather simple due to fixed

process in mixed stock and custom manufacturing system inventory

problem are more complex but control operations are rather simple due to

fixed process.

2. NATURE OF OPERATIONS/ACTIVITIES: In intermittent

manufacturing system the operations are markedly varied in terms of their

nature sequence and duration. Due to this the control procedure requires

continuous modifications and adjustments to suit the requirements of

each order.

3. MAGNITUDE OF OPERATIONS: Centralized control secures the

most effective co-coordinating but as an organization grows in size

decentralization of some production control function becomes necessary.

The degree to which the performance of an activity should be

decentralization depends upon the scope of operations and convenience

of their locations.

7.3. METHODS OF PRODUCTION CONTROL

Production control is done through routing scheduling dispatching and

follow up which have been elaborated as follows.

1. ROUTING: Routing is the first but the most important and difficult task

of the production control. Routing means determination of path route

which manufacturing operations will travel establishing the sequence of

operations to be followed in manufacturing a particular product. This

route path is determined in advance. Routing information is provided by

product or process engineering function and it is useful to prepare

machine loading charts and schedules.

2. SCHEDULING: It involves fixing priorities for each job and

determining the starting time and finishing time for each operation the

starting dates and finishing dates for each part sub assembly and final

assembly scheduling lays down a time table for production indicating the

total time required for the manufacture at a product and also the time

required for carrying out the operations for each part on each machine or

equipment.

3. DISPATCHING: The functions of routing and scheduling as discussed

above are paper work only. No actual production has yet been started

dispatching is the part of production control that translate the paper work


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into actual production in accordance with the detail worked out under

routing and scheduling functions.

FUNCTIONS OF DISPATCHING

Under dispatching the following are included

1. ISSUE OF MOVE ORDERS: Move orders are issued to movement

persons giving instructions regarding movement of raw materials form

stores so the manufacturing floor or from machine to machine as the a

case may be

2. ISSUE OF TOOL ORDERS: These are issued to the tool department to

collect and make ready tools and fixtures in advance of the time at which

the operations will commence.

3. ISSUE OF JOB ORDERS (JOB TICKETS): Job orders are issued to

the operations or job for men for starting the work. Job orders are

prepared in accordance with dates and times previously planned and

entered on the machine loading charts route sheets and progress control

sheets.

4. ISSUE OF INSPECTION ORDERS: Inspection orders are issued to the

inspection personal giving instructions regarding inspection centers type

of inspection required at different stages of operations gauges to be used

etc.

5. ISSUE OF DRAWING TIME TICKETS INSTRUCITONS CARDS

AND OTHER NECESSARY INFORMATION: These are issued to the

operations so that they will carry out their work smoothly without any

difficulty.

6. ISSUE OF STORE ORDERS: These orders are issued to the store to

supply the raw materials against the proper authorization.

7. EXPENDING/FOLLOW-UP : Expediting or progressing ensures that

the work is carried out as per the plan and delivery schedules are met.

Expediting is done after the dispatching functions. It keeps a close liaison

with scheduling in order to provide an efficient feedback and prompt

review of targets and schedules.


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7.4. BENEFITS OF PRODUCTION CONTROL

The benefits of production control given below

1. BETTER SERVICE TO CUSTOMERS: Promised delivery dates and

kept production flows as per scheduled time. This injects confidence in

the travelling salesman f the firm to set delivery dates. Delivery in time

wins customers confidence improves customer’s relation and promotes

profitable repeat orders.

2. LESS OVERTIME WORK: As flow of production is evened out

matched with the promised delivery dates or expected demand periods

there will be few rush firms in the same industry without adequate

production planning and control system.

3. NEED OF SMALLER INVENTORIES OF WORK IN PROCESS

AND FINISHED GOODS: Enterprises working under an effective

production planning and control system require lower inventories of

materials parts component etc. for work in process and less of finished

goods in stocks. These results in less investment in inventory funds thus

freed may be put to other more income earning uses. Also order to

customers can be supplied in full. This would bring the benefits of

economy transport costs because single large shipment generally costs

less than two or more small shipment.

4. MORE EFFECTIVE PURCHASING: Due to better materials

management leading to effective inventory control purchasing is more

scientific economically and timely.

5. LESS LOSS OF TIME: Because of purchased flow of material workers

need not wait for the material for long hence there will be less loss of

workmen hour’s time of executives is conserved in two days.

Their personal attention is claimed only when there is any series

flaw in the working of the system

Executive need not spend time on research data etc.

6. SAVING IN THE COST: A properly designed and introduced system of

production planning and control frequency results in major cost savings.

These savings are greater in amount than the cost involved in introduction

of the planning and control system.

7. LESS WORK STOPPAGE: Work stoppage are avoided or minimized

in terms of time duration. Obviously therefore delays in dispatch of goods

to customers are very infrequent.


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8. INDUSTRIAL HARMONY: Effective production control helps in

establishing harmonious industrial relations.

8. WORLD CLASS PRODUCTION/ MANUFACTURING

(WCM)

8.1. Concept of World Class Production Manufacturing:

World Class Production was originated with RICHARD J. Schonberger. World

Class Manufacturing, as one of the most known production systems in the

world, is a different set of concepts, principles, policies and techniques for

managing and operating a manufacturing company. It is driven by the results

achieved by the Japanese manufacturing resurgence following World War II,

and adapts many of the ideas used by the Japanese in automotive, electronics

and steel companies to gain a competitive edge. It primary focuses on continual

improvement in quality, cost, lead time, flexibility and customer service.

8.2. Framework of World Class Manufacturing

The goals of world -Class manufacturing efforts include maintaining

market share, improving profitability and improving the firm’s ability to

complete in a global market place whereas the general principles of improving

manufacturing performance are known. But there was a need to develop a

conceptual framework to establish the relationship between ‘manufacturing

performance’ and ‘business performance’ or’ world market dominance’. A

number of such frameworks developed by number of manufacturing

researchers/consultants are described as follows:

1). Hall’s Framework of value Added Engineering

2). Schonberger’s Framework of World Class Manufacturing

3). Gunn’s Model of World Class Manufacturing

4). Maskell’s Model of World Class Manufacturing

5).America’s Best Plants Model of World Class Manufacturing

__________

Manufacturing World Class Manufacturer

Excellence

FIGURE : Functions of World Class Manufacturing

Improved

Manufacturing

Performance

Improved Business

Performance

World Market

Domination


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8.3. Hall’s Framework of value Added Engineering

According to Hall (1987), manufacturing excellence is attained by ‘value added

manufacturing’, which is based on the principle that ‘purge anything that does

not add value to the product or service, whether material, equipment, space,

time, energy, systems or human activity of any sort.

The’ value added manufacturing ‘framework is based on several principles:

Take a broad view of operation.

Make problems visible to everyone.

Keep it simple.

Improve operations before spending on new plant and equipment.

Flexibility.

The frame work of ‘value added manufacturing’ nis described in three

overlaying categories of work, total quality, just-in-time manufacturing, and

people involvement. One cannot be successful with JIT or total quality without

total people involvement. Each of these is characterized by the following

basics:

JIT Manufacturing

Total Quality

Total People Involvement

1.Total Quality Control

Begin with the customer,

Measure and track quality,

Take a broad view of quality,

Set targets for improvement,

Fail-safe operations.

2.JIT Manufacturing: Only the right materials, parts and products in the right

place at the right time.


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3.Total People Involvement:

a) Broad perspective,

b) Problem-solving atmosphere,

c) Employment security,

d) Performance measurement.

8.4 Schonberger’s Framework of World Class Manufacturing (WCM)

According to Schonberger (1986), the goal of World Class Manufacturing

(WCM) is ‘continual and rapid improvement’. He argues that continual

improvement in quality, cost, lead time, customer service and flexibility will

lead to ‘World Class’ status. The WCM status can be achieved by any of the

two parallel paths:

The quality path, and

The JIT production path.

These are dominant WCM precepts for treating the ailment:

1. The JIT percept is based on the JIT principle – the smaller the lot size, the

better. WCM of cars, tractors, and motorcycles have some lot sizes down to

one unit by becoming adept at change- over’s between models.

2. The Total Quality Control (TQC) principle – do in right the first time.

3. The Total Productive Maintenance (TPM) – a regime of comprehensive

maintenance activity, carried- out largely by the operator (the “ owner “) of the

equipment and not by a maintenance specialist whose objective is to ensure zero

downtime of equipment.

While the JIT concept is natural in flow industries, it can work in discrete goods

manufacturing also. A WCM percept is to produce some of every type

everyday and in the quantities sold that day. Making more than that can be sold

costly and wasteful, and the cost and waste is magnified manifold as the

resulting Iumpiness in the demand pattern ripples back through all prior stages

of manufacture, including on bid supplier, In Schonberger’s opinion, if a WCM

effort fails to make it easier for cellular manufacturing, deviations reduction and

variability reduction.


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8.5. Gunn’s Model of World Class Manufacturing

According to Gunn, World Class Manufacturing rests on three pillars:

Computer Integrated Manufacturing (CIM).,

Total Quality Control (TQC) and

Just- In –Time (JIT) production methods.

These are the three fundamental approaches in modern manufacturing, which

may enable a manufacturer to gain competitive advantage for reaching world

class status. He proposes Arthur Young’s Manufacturing for Competitive

Advantage Framework to illustrate this point.

Management Resource

Integrated

Manufacturing

This frame work starts with a business unit’s strategic vision at the top, which

embodies the overall business objectives of the unit. This vision is based upon

two different ferames of reference:

The next level in the framework is integrated manufacturing. This has one

dimension of the entire range of activities , consisting of product and process

design, to manufacturing planning and control , to the production process itself,

to distribution, and to after- sales service and support , and the other dimensions

consisting of customers and suppliers. The framework also shows that the main

interface from integrated manufacturing has been through the distribution

Global Competitors

Strategic Vision

-----------------------------------

World Class

Manufacturing

Global Markets

Quality

Human Resources

Technology

Planning

Customers

Suppliers

Product and Process

Design

Planning and Control

Production

Distribution

Service

Service

T C J

Q I I

C M T

C

M

Q

C


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function. However, According to Gunn, all the five functions within

manufacturing should be engaged in an ongoing dialogue with their customers.

8.6. Maskell’s Model of World Class Manufacturing

According to Maskell, World class manufacturing generally includes the

following:

A new approach to product quality,

Just- In-Time (JIT) production techniques,

Change in the way the workforce is managed, and

A flexible approach to customer requirements.

In terms of quality, the world class manufacturing approach emphasizes on the

resolution of the problems that causes poor quality, rather than mere detection

of those problems. The purpose is to systematically expose and resolve the root

causes of quality problems so that the company can ideally achieve zero defects

or 100 per cent quality. A second aspect of the new approach is that quality

control responsibility is placed on the shop floor with production operations.

This goal is achieved by;

1. Change of the shop-floor layout to reduce the movement of materials.

2. Reduction in production set-up times so that products can be made in very

small batches (ideally a lot size of one).

3. Creating mutually beneficial relationships with suppliers, using techniques

such as single sourcing, certification and openness.

Some of the new approaches to the management of people are:

1.Transfer of Responsibility: A world class manufacturer should give operators

greater control of their daily work. They will have prime responsibility for

product quality, scheduling preventive maintenance and for attaining production

targets.

2.Education and Cross- Training: World class manufacturers spend a lot of

time and money to educate their employees in areas such as JIT manufacturing ,

quality control and customer service as well as train them to do a wide range of

tasks within the production plant.

3.Problem –Solving and Quality Circles: The purpose of quality circles is to

have every employee involved in solving production problems. These programs

have very successful in many companies because they create an environment of

team involvement and common cause, which enables people, who previously


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had very little opportunity to contribute, to become innovative and resourceful

problem-solvers.

There are two aspects of flexibility that are important.

1.Production Flexibility : Production flexibility is achieved when the company

can offer short lead times, when the product mix within the plant can be

changed significantly from day to day, and when people within the plant are

cross-trained to manufacture a wider range of products.

1.Design Flexibility: Design flexibility is related to the company’s ability to

introduce new products and modifications to current products.

8.7. America’s Best Plants Model of World Class Manufacturing

‘Industry Week’ conducts a survey of American Plants to identify which of

them is world class. Whereas the questionnaire for this survey was a very

detailed one, the characteristics of world class manufacturing are identified by

the three core strategies:

Customer focus,

Quality, and

Agility .

These form the foundation for ‘ Best Plants’ performance, and six supporting

competencies:

1. Employee’s involvement,

2. Supply management,

3. Technology,

4. Product development,

5. Corporate citizenship.

The supporting competencies help the plants to achieve the goals, defined in

the three core strategies. The three core strategies are at the same time both

philosophical and tangible goals. Customer focus has always been a primary

requirement of business. Customers should occupy the centre of a

manufacturing operations. In the best plants, the customer is the king. Quality

is the second core strategy. In America’s best plants, quality is viewed as defect

free, waste- free workmanship that is derived from products and process quality,

lastly, agility has been defined as lean manufacturing and just- in-time supply

practices.


20 | P a g e


8.8. STEPS IN WORLD CLASS MANUFACTURING:

Peter Stonebreaker And Keong Leong presented a hierarchy of steps, appearing

as five levels, which lead to world class operations.

1.Level One : Business and Operations Strategy: All world class manufacturers

have an explicit, formal manufacturing mission. Within this mission is the

operating goal to become world class. They use competitive information to

establish organizational goals and objectives, which they communicate to all

members of the enterprise.

2.Level two : Organization Design. Human Resources, Technology, and

performance Measurement: The following sections discuss how organization

design, human resources, technology and performance measurement factor into

an organization’s effort to become a world class manufacturer;

A)Organization Design: World class manufacturers integrate all elements of

the manufacturing system in such a way that the needs and wants of its

customers are satisfied in an effective, timely manner.

B)Human Resources: World class manufacturers recognize that employee

involvement and empowerment are critical for achieving continuous

improvement in all elements of the manufacturing system.

C)Technology: A great deal of emphasis is placed on technology, equipment,

and processes for attaining world class status. World class manufacturers view

technology as a strategic tool for achieving and maintaining their world class

status.

D) Performance Measurement: World class manufacturers recognize the

importance of measurement in defining the goals and performance expectations

for their organization.

1. Level Three: Information Systems, Management Direction, and operations

Capabilities

a)information Systems: World class manufacturers require world class

information systems for collecting , processing, and disseminating data and for

providing the feedback mechanism that is necessary for meeting their

objectives.

b)Management Direction: Management is responsible for directing the

manufacturing organizations journey to world class status and for creating an

organizational culture committed to all that is necessary for achieving

continuous improvement. Corporate culture and values are the foundation for

superior manufacturing, which in turn reflects and is reflected by the caliber of

corporate management.


21 | P a g e


c) Operations Capabilities: World class manufacturers are concerned with

whether their operations system have the ability to meet design specifications,

rather than with evaluating the quality and quantity of products after the fact. In

order to attain world class status, the manufacturing firm has to be given the

proper resources.

4) Level Four: Quality: World class manufacturers place an emphasis on

quality. Firms in this category are usually in an advanced state of TQM

implementation, continually seeking to enhance their business. All quality costs

are evaluated and held to the lowest reasonable sum.

5) Level Five: Customer Service: World class manufacturers in still within their

organization and constantly reinforce the idea that all who are a part of the

organization must know their customers and seek to stratify the wants and needs

of not only the customers, but also all other stakeholders.

6) Level Six: While world class manufacturing may be difficult for

manufacturers to define many say they know it when they see it. Whatever it is,

it must be form the customer’s vantage point. An ‘Industry Week’ survey found

that among factories approaching world class status, a higher percentage were

likely to belong to public companies; have corporate parents with revenues

greater than $1 billion; participate in an automotive industry value chain; and

employee 250 or more people at the location.

8.9. Importance of World Class Manufacturing:

As companies introduce world class manufacturing techniques, they need new

methods of performance measurement to control production plants.

These new methods are needed because:

1. Traditional management accounting is not relevant to world class

manufacturing

2. Customers are requiring higher standards of quality, performance, and

flexibility.

3. New management methods employed by world class manufacturers require

different kinds of performance measures.

World class manufacturing concept is of a recent origin. The following

attributes of the world class manufacturing are aimed to fulfill the customer

demands:

1. Products with high quality,

2. Products at competitive price,

3. Products with several enhanced features,


22 | P a g e


4. Products in a wider variety,

5. Products delivered with shorter lead time,

6. Products delivered on time,

7. Flexibility in fulfilling products demand,

All these performance measures are external to the manufacturing system but

highly essential for the success of the company. These can be measured

internally. Companies must set-up their performance measures in these lines so

that the product will have a high level of acceptance at customer point.

IMPORTANT QUESTIONS:

1. Explain about line of balance and its importance in POM.

2. Explain the methods of production control.

PREPARED BY; V SREERAM YASHASVEE B.COM., L.L.B., M.B.A., (C.A.)

ASST.PROFESSOR, BALAJI INSTITUTE OF IT & MANAGEMENT, KADAPA.

http://b.com/

SEMESTER - II OPERATIONS MANAGEMENT

UNIT - 4 Work Study & Quality Management | BALAJI INST OF IT AND MANAGEMENT Page 1

SYLLUBUS (17E00206) OPERATIONS MANAGEMENT


Controlling aspects of a typical production and operations organization. Study understands

the concepts of work study and Quality management.




2. Facilities Management & Aggregate Planning: Location of Facilities, Layout of

Facilities, Optimization of Product/ Process Layout, Flexible Manufacturing and Group

Technology: Aggregate Planning – Preparation of Aggregate Demand Forecast, specification

of Organizational Policies For Something, Capacity Utilization, Determination of feasible




Production.






Issues in Materials Management - Functions - Activities - Selection of Materials -

Advantages of Materials Management.

Text Books:

Production and Operations Management, Aswathappa K - Himalaya Publishing

House


References:



Science Press

Production and Operations Management, R.Panneerselvam: PHI Learning Private

Ltd.



Wiley ...




Books



UNIT - 4

WORK STUDY AND QUALITY MANAGEMENT

1. INTRODUCTION TO WORK STUDY:

Work study is the systematic examination of the methods of caring on activities so as to

improve the effective use of resources and set up standards of performance for activities

being carried out.

1.1 DEFINITION:

According to a British standard (BS 3138) work study refers to the method study and work

measurement which are used to examine human work in all its contexts by systematically

investigating into all factors affecting its effectiveness efficiency and economy to bring forth

the desired improvement.

1.2 OBJECTIVES:

1. Provide more and improved physical means to motivate the workers.

2. Improve the basic process by research and development

3. Improve man power efficiency at all levels.

4. Improve organization product planning and control

1.3 WORK STUDY PROCEDURE:

1. SELECT: Select the job or process to be studied

2. RECORD: Record and collect all relevant data about the job or process using most

suitable data collection techniques.

3. EXAMINE: Examine critically the recorded facts and challenge everything that is

done purpose place sequence and person.

4. DEVELOP: Develop the most economic method by considering all the

circumstances various production management techniques.

5. EVALUATE: Evaluate the results attained by the improved method compared with

the quantity of work involved and calculate a standard time for it.

6. DEFINE: Define the new method and the related time and present it to all those.

7. INSTALL: Install the new method training those involved as an agreed practice

with allocated time of operation.

8. MAINTAIN: Maintain the new standard practice by monitoring the results and

comparing them with the original targets.

1.4 BENEFITS/ADVANTAGES:

1. Work study directly leads to standardization of job process.

2. It determines the cost of the work performed.

3. It saves and minimizes time since the unnecessary movements are eliminated.

4. It enhances productivity of the workers and machines.

5. It facilitates the organization to plan and achieve work targets.



1.5 DISADVANTAGES:

1. Unnecessary managerial dictation and discipline.

2. Tending to transfer to the management all the traditional knowledge the judgment and

skills of workers.

Work study is divided into two parts. They are,

1. Method study and

2. Work measurement

2. METHOD STUDY: Method study is the systematic recording and critical examination of the existing and

proposed ways of doing work and developing and applying easier and more effective

methods to reduce the costs and increasing efficiency.

2.1 METHOD STUDY PROCEDURE:

Work measurement Method study

Work study

Method study

Aim: to develop better working

methods

PROCEDURE

SELECT the test to be studied

RECORD all related facts about current or

proposed methods

EXAMINE the facts critically considering the

purpose, sequence place and resources

DEVELOP the best possible method

DEFINE the best method so developed

INSTALL the new method

MAINTAIN the installed method

RESULTS

Increased efficiency cost effectiveness

and productivity through

Improved workplace layout

Improved equipment design

Reduction in worker fatigue

Improved product/process design



2.2 OBJECTIVES OF METHOD STUDY:

1. Improvement in use of all the inputs i.e. men, machines materials, money, time and

information.

2. Improvement in design of plant and equipment.

3. Improvement in safety standards and procedures.

4. Developing better working environment.

2.3 RECORDING TECHNIQUES OF METHOD STUDY:

The recording techniques are of three types.

1. Process charts

2. Diagrams and motion and film analysis

2.3.1. PROCESS CHARTS:

A. OUTLINE PROCESS CHARTS:

This chart outlines the main events sequence wise considering only operations and

inspections in the given job.

B. FLOW PROCES CHARTS:

These are scale drawings of the work place, which indicate where each activity takes place.

This chart is capable of reflecting under delays in transferring work between work stations

duplication of work delay in completion process etc.

C. TWO HANDED PROCESS CHARTS:

This presents the simultaneous activities of both the right and left hand of an operator during

works of short and repetitive nature.

D. MULTIPLE ACTIVITY CHARTS: These charts are used to depict interactions between several machines or items of equipment

which are deployed alongside each other in a work station. Here the activities of such

machinery/ equipment can be recorded against a common time scale. The working time is

considered on the vertical axis and machines are taken on the horizontal.

2.3.2. DIAGRAMS:

A. FLOW DIAGRAM:

It is a diagram drawn to scale, intended to show the relative position of the production

machinery and marks the route followed by the machines materials and men.

B. STRING DIAGRAMS:

These are similar to flow diagrams. Here movements between activities are recorded by

means of string thread or connecting pins inserted into all the activity points on the diagram.

This diagram enables paths of all the movements and records with clarity. These diagrams

highlight the shortcuts.

C. CYCLE GRAPHS:

In this method a small electric bulb is attached to each part of the body which makes the

movement for carrying out an operation. The path of movement is photo graphed by a high

speed camera.

D. TRAVEL CHARTS:

A Travel Chart is a tabular record for presenting quantitative data about the movement of

worker, materials or equipment's between any number of places over a given period of time.

The travel chart is always in a square shape. Within this shape, the square has many smaller

squares which depict a workstation.



E. CHRONOCYCLE GRAPH:

The light source is interrupted for depicting the path as a pear shaped diagram. This type of

graph shows both the direction as well as the speed of actions.

2.3.3. MOTION AND FILM ANALYSIS:

Therbligs are basic unit of work activity used in micro motion studies which are detailed

studies of repetitive work. Here simultaneous motion cycle charts are used which record on a

time scale, the simultaneous minute movements performed by the two hands of an operator.

3. WORK MEASUREMENT:

Work measurement is also called as time study. It establishes the time taken by a qualified

worker to complete specified job at a defined level of performance.

3.1 OBJECTIVES:

1. To develop costing systems like budgets.

2. To determine production schedules

3. To develop incentive schemes

4. To compare alternative methods of given jobs

5. To standardize the job in terms of standard time

6. To determine the optimum number of men and machines to ensure their effective

utilization.

3.2 WORK MEASUREMENT PROCEDURE:

1. DESCRIBE:

The essential prerequisite to carryout work measurement is to describe the method underlying

the job and focus on proposing a new method.

2. BREAK:

Break the job into elements which can be identified as distinct parts of an operation capable

of being observed measured and analyzed.

3. MEASURE:

Measure time than to perform each element using a stop watch (ideally each element should

not take more than 30 seconds)

4. DETERMINE:

Add the time taken to do all the elements and arrive at eh basic time (normal time) required to

do the entire job.

3.3. TECHNIQUES OF WORK MEASUREMENT:

A number of work measurement techniques have been developed to suit different types of

work. They are as follows:

3.3.1. REPETITIVE WORK: The type of work in which the main operation or group of operations recurs continuously.

3.3.2. NON REPETITIVE WORK:

It includes some types of maintenance and construction work where the work cycle is ever

repeated identically.



The different techniques for the different types of work are represented as follows:

3.3.2.1. TIME STUDY OR STOP WATCH STUDY:

Time study is concerned with the determination of amount of time required to perform a unit

of work. It records the time required to perform each element.

3.3.2.2. OBJECTIVES OF TIME STUDY:

a. To determine the cycle time for completion of a job

b. To set the completion schedules for individual operations

c. To set labor standard for satisfactory performance.

d. To determine the quantity of human work in a specified task and hence the establish

the standard time

e. To determine standard costs.

Work measurement

Aim: to develop time standard

PROCEDURE

DESCRIBE the given work for measurement

BREAK the job into elements

MEASURE the performance of operator

DETERMINE the basis time

PROVIDE time allowance for fatigue etc.

DETERMINE standard time

RESULT

Increased efficiency and higher productivity through

Scientific basis to develop incentive systems

Maintain reasonable of employment

Reliable means of planning and control



3.3.2.3 TIME STUDY PROCEDURE:

1. SELECT THE JOB TO BE STUDIED:

The reasons for selecting a job for time study are,

1. New job taken for production

2. Design change

3. Change in manufacturing method

2. SELECT THE WORKER TO BE STUDIED:

The ideal worker would be the qualified worker. Since the ideal worker or qualified worker

may not be available in the organization the best available worker is chosen and his rating is

determined as compared with the qualified worker.

3. CONDUCTING STOP WATCH TIME STUDY:

1. Obtain and record all information available about the job operation and working

conditions.

2. Record the method of doing the job and break down into elements (like repetitive

element, constant element)

3. Examine the various elements to ensure that the most effective motions are used in the

elements of job performed.

4. WORK DESIGN:

Work design is the study and design of a work system in an organizational context.

Technologically work is viewed as tools. Techniques and methods used for production of

finished goods. The economic concept of work is associated with wages and employment.

Work design seeks to increase productivity by seeking better and less expensive ways to

perform the functions tasks. The man material machine combination is the focus of any work

problem. This is the part of the entire organization work system work design is a systematic

investigation of desired and present work systems to get the ideal work systems and methods.

4.1 ASSUMPTIONS OF WORK DESIGN:

1. Work systems try to improve productivity and effectiveness.

2. Work systems are in three states design betterment improvement

3. Work design considers all aspects of the work system

4. Work design integrates abilities and talents

5. Work design goes beyond a set of techniques since work systems need continuous

monitoring.



4.2 COMPONENTS OF WORK DESIGN:

The figure below shows the various components of work design.

4.2.1. JOB DESIGN:

Job design is defined as the process of deciding on the content of a job in terms of its duties

and responsibilities. It answers the questions of how the job is to be performed that perform it

and where it is to be performed.

Thus in a way job design greatly affects how an employee feels about the job. How much

authority an employee has over the work? How much decision making the employee has on the

job?

4.2.2. OBJECTIVES OR GOALS OF JOB DESIGN:

The main objectives of the job design are as follows,

1. To meet the organizational requirements such as higher productivity operational

efficiency quality of product/service etc.

2. To satisfy the needs of the individuals employees like interests, challenge

achievement or accomplishment etc.

3. To integrate the needs of the individuals with the organizational requirements.

4.2.3. FACTORS AFFECTING JOB DESIGN:

Job design is affected by organizational environmental and behavioral factors. A properly

designed job will make it productive and satisfying. It a job fails on this count the job

designers who must redesign the job based o the feedback. The factors are explained below.

Work design

Job design

Work measurement

Methods of

analysis

Job

enlargement

rotation and

enrichment

Principles of

motion

economy

Stop watch

time study

Work

sampling

Flow process

chart

Employee

machine

activity chart



1. ORGANISATIONAL FACTORS:

A. CHARACTERISTICS OF TASK:

Job design requires the assembly of a number of tasks into a job or a group of jobs. An

individual may carry out one of main task which consists of a number of interrelated

elements of functions.

B. WORK FLOW:

The flow of work in an organization is strongly influenced by the nature of the product or

service the product or service usually suggest the sequence and balance between jobs.

C. ERGONOMICS:

This is concerned with designing and shaping jobs to fit the physical abilities and

characteristics of individual also.

D. WORK PRACTICES:

These are set ways of performing works. These methods may arise from tradition are the

collective wishes of employees failure to consider work practices can have unwanted

outcomes.

2. ENVIRONMENTAL FACTORS:

A. EMPLOYEE ABILITIES AND AVAILABILITY:

Efficiency consideration must be balanced against the abilities and availability of the people

who are to do the work.

B. SOCIAL AND CULTURE EXPERIANCES:

Literacy knowledge and awareness among workers have improved considerable so also their

expectations from jobs. Hence jobs must be designed to meet the expectations of the workers.

3. BEHAVIOURAL ELEMENTS:

A. FEEDBACK:

Individuals must receive meaningful feedback about their performance. This implies that they

should ideally work on a complete product or a significant part of it.

B. AUTONOMY:

This is being responsible for what one does. It is the freedom to control ones responds to the

environment. The absence of autonomy can cause employees boredom or poor performance.

C. USE OF ABILITIES:

The job must be perceived by individuals as requiring them to use abilities they value in order

to perform the job effectively.

D. VARIETY:

Lack of variety may cause boredom. In turn boredom leads to fixedness which causes

mistakes. By injecting variety into jobs personnel specialists can reduce errors caused by

fatigue.

4.2.4. TECHNIQUES OF JOB DESIGN:

1. WORK SIMPLIFICATION:

In these techniques the job is simplified or specialized a given job is broken down into small

subparts and each part is assigned to one individual. To be more specific wok simplification

involves:

Mechanical packing of work

Repetitive work process such as those on an assembly line

Working on only part of a product



Few skill requirements

2. JOB RELATIVE:

Job rotation implies movement of employees from one job to other job. Jobs remains

unchanged but incumbents shift with job relation a given employees perform different jobs

but more or less jobs of the same nature.

3. JOB ENLARGEMENT:

Job enlargement involves expanding the number of tasks or duties assigned to a given job.

Job enlargement is naturally opposite to work simplification.

Adding more tasks or duties to a job does not mean that new skills are needed to perform it.

4. JOB ENRICHMENT:

An enriched job will have more responsibility and autonomy more variety of tasks and more

growth opportunities. The employee does more planning and controlling with less

supervision but more self evaluation.

5. AUTONOMOUS OR SELF DIRECTLY TEAMS:

Employment results in self directed work teams a self directed work teams is an intact group

of employees.

6. INDUSTRIAL ENGINEERING: Industrial engineering is concerned with the design improvement and installation of

integration system of men materials and equipment. It draws upon specialized knowledge and

skill in the mathematical physical and social sciences together with the principal and methods

of engineering analyses and design to specify predict and evaluate the results to be obtained

from such system.

4.2.4.6.1. TECHNIQUES OF INDUSTRIAL ENGINEERING: The main aim of tools and techniques of industrial engineering is to improve the productivity

of the organization by optimum utilization of organizations resource like men materials and

machines. The major tools and techniques used in industrial engineering are described below:

1. METHOD STUDY:

Method study is used to established standard method of performing a job after thorough

analysis of the job and to establish the facilities layout at a defined level.

2. WORK MEASUREMENTS:

The application of techniques designed to establish time for a qualified worker to carry out a

specified job at a defined of performance.

3. PRINCIPAL OF MOTION ECONOMY:

These rules and principles can be applied to improve the efficiency and reduce tidiness in

performing manual work.

4. JOB ANALYSIS AND INCENTIVES LIKE FINANCIAL OR NON-FINANCIAL:

Job analysis helps to evolve a rational compensation for the efforts of the workers.

5. VALUE ANALYSIS:

It ensures that necessary costs are built into the product and it tries to provide the required

function of the minimum cost. Hence helps to enhance the worth of the product.

6. PRODUCTION PLANNING AND CONTROL:

It includes the planning for the resources, proper scheduling and controlling production

activities.

7. INVENTORY CONTROL:

It is used to determine the economic lot size and the recorder levels for the items so that it is

available to the production center at the right time, in proper qualify to avoid stock out.

8. JOB EVALUATION:

Techniques used to determine the relative worth of jobs of the organization to aid in matching

jobs and personal and to evolve sound wage policy.



9. FACILITIES PLAN AND MATERIAL HANDLING:

It is used to systematically plan the materials movement through the plant eliminating back

tracking and unnecessary movements.

10. HUMAN FACTORS:

It is concerned with relationship between the man and his working environment to minimize

physical and mental stress.

11. SYSTEM ANALYSIS:

System analysis is study or various sub system and elements that make a system their

interdependencies in order to design.

12. OPERATION RESEARCH:

Operations research is technical used to obtain optimal solution to the problems based on a

set objective and constraints imposed on the problem. The techniques most often in use are,

Linear programming

Simulation

Network analysis

Queuing models

Assignment sequencing and transportation models

Game theory and dynamic programming

13. CONTINUOUS IMPROVEMENT:

Organization and methods

Group technology

Statistical techniques

Advances in IT and computer packages etc.

5. WORK SAMPLING

5.1 MEANING OF WORK SAMPLING :

Work sampling also called ‘Activity Sampling’ or ‘Ratio Delay Study’, is based on the

statistical method first devised by L.H.S Tippet in 1934. He used this technique firstly in the

British textile industry. Later Morrow carried out several investigations.

5.2 OBJECTIVES OF WORK SAMPLING:

Work sampling is a fact finding tool and has the following two main objectives:

1. To measure activities and delays while a man is working and percentage of that he is

not working. It means a fair day’s work.

2. Under certain circumstances, to measure manual tasks that is to establish time

standards for an operation.

5.3 THEORY OF WORK SAMPLING:

It states that the percentage of observations recorded on an operation in any state is a reliable

estimate of the percentage time the operation is in that state, provided, “sufficient numbers of

observations are taken at random”. Here particular stress should be paid on the words

“random” and “sufficient number of observations”.

In this method, error is likely to occur but the error tends to diminish as the number of

samples increases.

For example, in the following table, there are 36 working observations and four idle

observations, i.e. a total of 40 observations.



This study is for one operator for 8 hours a day indicates that the operator was idle for 10% or

48 minutes of the day while working for 90 % or 432 minutes of the day.

1. Confidence Level :

It is important to decide as to what level of confidence is desired in the final “Work

Sampling” results. The most common confidence level is 95%. The area under the curve at 2

sigma or two standard deviations is 95.45%, which is rounded off to 95%. This means that

the probability is that 95% of the time the random observations will represent the facts and

5% of the time they will not.

For many cases, an accuracy of + 5% is considered satisfactory. This is sometimes referred as

the standard error in percentage.

Sample size Determination:

To get a desired accuracy, an analyst must take sufficient number of observations.

For calculating the number of observations required for achieving the desired accuracy,

following formula is used:

5.4. PROCEDURE FOR WORK SAMPLING STUDY:

The following steps are involved in making a “Work Sampling” study:

1. Define the Problem

(a) State the main Objectives or purpose of the problem

(b) Describe the details of each element to be measured.

http://cdn4.businessmanagementideas.com/wp-content/uploads/2016/11/clip_image002-14.jpg





2. Obtain the approval of the incharge of the department in which study is to be made.

Obtain the co-operation of the operators to be studied and they should also understand

the purpose of the study.

3. Determine the desired accuracy of the final results in the form of standard error or

percentage.

4. State the Confidence level.

5. Make a preliminary estimate of the percentage occurrence of the activity or delay to

be measured for one day or two days. This may be estimated on the basis of past

experience.

6. Design the study,

(a) Determine the number of:

a. Observations to be made

b. Observations needed. Select and instruct them

c. Days or shifts needed for the study

(b) Make plans for taking the observations such as time for taking and the route to be

followed by the observer.

(c) Design the observations form.

7. Make the observations and record the data

8. Summarize the data at the end of each day

9. Check the accuracy or precision of the data at the end of the study

10. Prepare the report and state results. If required make recommendations.

5.5. DETERMATION OF TIME STANDARDS BY WORK SAMPLING:

With Work Sampling, it is possible to determine the percentage of the day a worker is idle

and the percentage of the day he is working. The average performance index or the speed at

which he worked during the working portion of the day can also be determined.

Standard Time:

5.6. APPLICATION OF WORK SAMPLING:

1. Work Sampling can be applied for the estimation of the percentage utilization of

machine tools, cranes, fork trucks etc.

2. Work Sampling can also be used to estimate the unavoidable delay times for deciding

the delay allowances.

3. To estimate the percentage of the time consumed by various job activities, i.e.,

supervision, repair, inspection etc.,

4. Work Sampling is also used to find out time standards, specially where the job is not

repetitive and where time study by stop-watch method is not possible,

5.7. ADVANTAGES OF ‘WORK SAMPLING OVER TIME STUDY”:

1. Operator is not subjected to long-period of observations.

2. Group operations can be easily studied by a single analyst.




3. It does not require continuous observation for a long period of time.

4. Many operations or activities which are impractical or costly to be measured by time

study and can be measured by this.

5. Observations may be taken over a period of days or weeks, thus decreasing the chance

of day to day or week to week variations affecting the results.

6. The man hours spent by the analyst are much less.

7. A work sampling study can be stopped at any time without affecting the results.

8. In this, random observations are taken by avoiding prolonged observations.

9. This produces less fatigue and is less tedious to observer.

10. It generally requires less time in calculating the results.

5.8. DISADVANTAGES OF “WORK SAMPLING” OVER “TIME STUDY”:

1. It is not economical to study a single operator or machine or for studying operators or

machines located over wide areas.

2. It does not permit finer breakdown of activities and delays.

3. Study made of a group presents average while there is no information about the

magnitude of individual differences.

4. Management and workers may not be able to understand work sampling as easily as

they do time study.

5. Some time no record is kept about the study on the operator, therefore, a new study

must be made when a change occurs in any element.

5.9.ERRORS IN WORK SAMPLING STUDY:

Following are some of the errors which generally occur:

1. SAMPLING ERRORS:

In sampling study, whole population is represented by a sample. If the size of the

sample is small, then there are chances of errors in inference drawn from this sample.

Therefore, while conducting the study care must be taken that the sample size must

represent the same characteristics as that of the whole population.

The sample size can be calculated using the formulae, after a confidence level and

level of accuracy is decided. After completing the study, it must be checked, whether

sufficient number of observations have been taken or not.

2. BIAS IN WORK SAMPLING:

As a consequence of bias in study, the proportion of an activity (working or idle) shall

be different from the actual proportion of time devoted to that activity.

Following are the main sources of Bias Study:

(i) A Non-Random schedule of Observation:

Once the number of observations have been estimated (after deciding the

confidence level and accuracy) using the formula and a representative period

(number of days over which the study in spread-up) of study has been

selected, the number of observations (N) are distributed over the total number

of days selected.

(ii) Bias on the part of the Observer:

Sometimes when the observer observes the worker he is in transitional states,

i.e., he is changing from one state to another state and then the observer can

call it either way. In such cases, the observer’s judgment is required.



(iii) Change in the Behaviour of the worker:

Sometimes, when the observed person knows that he is being observed then he

changes his behavior.

3. NON-REPRESENTATIVENESS IN WORK SAMPLING:

Non-Representativeness exits when the period studied do not give characteristics of

the circumstances that prevail in the long run.

For Example, results taken on any one day cannot represent all the days. On Monday,

the worker is fresh while on Friday and Saturday he will be tired.

Similarly, the results taken in the day shift, evening shift and in the night shift will be

different.

6. TOTAL QUALITY MANAGEMENT (TQM):

Total quality management is a management system for a customer focused organization that

involves all employees in continual improvement of all aspects of the organization. Total

quality management is a management approach to long-term success through customer

satisfaction. In a TQM effort all members of a n organization participate in improving

processes, products services and the culture in which they work.

6.1.NEED AND IMPORTANCE OF TQM:

1. Better employee relations

2. Improved operational performance

3. Greater customer satisfaction

4. Improves organizational development

5. Promotes supplies and customer satisfaction

6.2. ELEMENTS OF TQM

1. Ethics – good and bad

2. Integrity – honesty, values and morale

3. Trust – ethical conduct

4. Communication – sharing of ideas with each other

5. Team work

6. Leadership

7. Training

6.3. PRINCIPLES OF TQM:

TQM principles can be used by senior management as a form work to guide their

organization towards improved performance. The principles are derived from the collective

experience and knowledge of the international experts which is responsible for developing

and maintaining the ISO 9000 standards. The eight quality management principles are as

follows:

1. CUSTOMER FOCUS:

Organizations depend on their customers and therefore should understand current and future

customer needs and strive to exceed customer expectations. The organization must be

customer focus.

2. LEADERSHIP:

Leaders establish unity of purpose and direction of the organization. They should create and

maintain the internal environment in which people can become fully involved in achieving

the organizations objectives.



3. INVOLVEMENT OF PEOPLE/EMPLOYEE INVOLVEMENT:

A motivated committed and involved employee within the organization and their full

involvement enables their abilities to be used for the organizations benefits.

4. PROCESS APPROACH:

A desired result is achieved more efficiently when activities and related resources are

managed as a process.

5. SYSTEMATIC APPROACH TO MANAGEMENT:

Identifying, understanding and managing interrelated process as a system contributes to the

organizations effectiveness and efficiency in achieving its objectives.

6. CONTINUAL IMPROVEMENT:

Continual improvement of the organizations overall performance should be a permanent

objectives of the organization.

7. FACTUAL APPROACH TO DECISION MAKING:

Effective decisions are based on the logical and intuitive analysis of data and information.

8. MUTUALLY BENEFICIAL SUPPLIERS RELATIONSHIP:

An organization and its supplies are interdependent and a mutually beneficial relationship

enhances the ability of both to create value.

6.4. TOOLS OF TQM:

1. FISH BONE DIAGRAM:

It is also called as cause and effect diagram. This diagram is used to explore all the potential

or real causes that result in a single effect.

2. HISTOGRAM:

Histogram is a graphical representation of discrete groups or categories of data. This chart is

normally used to emphasis the variation and unevenness of data.

3. CONTROL CHARTS:

A control chart is a statistical technique for controlling the quality of a product being

manufactured.

6.5. LIMITATIONS OF TQM:

Cost in time and money

People fear change

Reduction in innovation

Resistance to change

7. MEANING AND DEFINITION OF QUALITY Quality is a trait character features attribute property quality is the totality of features and

characteristics of a product or service that bear on its ability to satisfy a given need.

7.1.MEANING OF QUALITY MANAGEMENT:

Quality management is focused not only on product quality but also the means to achieve it.

Quality management can be considered to have three main components quality control

quality assurance and quality improvement.



7.2. OBJECTIVES OF QUALITY MANAGEMENT:

1. To access the quality

2. To see whether the products conform to the predetermined standards

3. To locate the reason for deviations and to take necessary remedial steps

4. To develop quality consciousness

5. To reduce wastage

8. MEANING OF QUALITY ASSURANCE:

Quality assurance refers to the assurance to customers that the product parts, components,

tools etc. contain specified characteristics and are fit for the intended use. Assurance of

quality is not a responsibility of a single person or department only. Inspection department or

its personnel cannot be held responsible for assurance of quality. It is the responsibility of

everybody connected with the production directly or indirectly.

8.1 FORM OF QUALITY ASSURANCE:

1. QUALITY AUDIT:

A quality audit is an independent review conducted to compare some aspect of quality

performance with a standard for that performance. Quality audit is a systematic independent

examination and evaluation to determine whether quality activities and result comply with

planned arrangements and whether these arrangements are implemented effectively and are

suitable for achieving objectives.

PURPOSE OF QUALITY AUDIT

Opportunities for improvement are identified and the appropriate personal alerted.

Plans for quality attainment

Deficiencies are identified and corrective action is taken

To provide accurate and adequate information on quality

2. QUALITY SURVEYS:

Quality audits are however not sufficient to provide full assurance to upper management. The

broader review is often called a quality survey. These quality surveys are used to give

information and challenges to top management regarding product development and design

engineering with regard.

3. PRODUCT AUDIT:

Product audit it an independent evaluation of product quality to determine its fitness for use

and conformance to specification product auditing takes place after inspection have been

completed.

9. QUALITY CONTROL:

Quality control is a technique where the management tries to confirm the quality of the

product in accordance with the pre-determined standards and specifications. It is a systematic

control of those variables that affect the excellence of the ultimate product.

OR

Quality control may be defined as that industrial management techniques or group of

techniques by means of which products of uniform acceptable quality are manufactured.



9.1.OBJECTIVES OF QUALITY CONTROL:

1. To assess the quality

2. To see whether the product conforms to the pre-determined standards

3. To develop quality consciousness

4. Locate the reason for deviations and to take necessary re-medical steps

5. To reduce the wastage

9.2. IMPORTANCE OF QUALITY CONTROL:

1. REDUCED COSTS/REDUCTION IN COSTS:

An efficient quality control system reduces the cost of production of the product due to:

Reduction in wastage of raw materials

Large scale production of standard quality product

2. IMPROVEMENT IN MORALE OF EMPLOYEES:

By quality control program, the employees become quality conscious. They understand the

standards of the product well and try to improve the standards and produce the quality goods.

3. MAXIMUM UTILIZATION OF RESOURCES:

By establishing the quality control system the necessary control over the machines equipment

men and material and all other resources of the company is exercised the quality control

resources of the company is miss use of facilities and wastage so that the resources are

effectively utilized.

4. INCREASE IN SALES:

Increase in sale of the product is the main objective of the quality control system by this

product is made available to the consumers at lower rates this in turn increase the product

demand.

5. CUSTOMER SATISFACTION:

Consumer/customers always get satisfaction if standard products with specifications are

available at cheaper rates.

10. ECONOMICS OF QUALITY ASSURANCE:

Quality cost may at first seem high due to NDT equipment measuring instruments suppliers

training and qualified personnel/labor reduced quality may result in low reliability, rework,

rejection, down time, which may give rise to complains failures losses and hazards to human

beings and the environment on the other hand if the requirements for quality. Reliability

safety and availability is high product costs will be unnecessarily high one of the basic

management duties is to strike on optimum balance between the various costs of quality

assurance. Elements of quality costs and quality cost model are shown in figure A.

Production costs rise disproportionately as designers tighten tolerances. One way to decide

where tolerances should be tight is to make a Pareto analysis of the dimensions and

tolerances of the work. This method classifies the elements of a total unit in the order of their

importance to the performance of that unit. Such a classification of dimensions includes

functionality critical significant and significant only for good appearance and for good

workmanship. Viet cities the Pareto analysis of 5000 dimensions of a pressure vessel which

showed that only 5% of the dimensions are critical 18% are significant and the remaining

77% dimensions require only good workmanship and acceptable appearance. Keeping in



mind that under a quality control system every out of tolerance dimension is considered non-

conforming decide just exactly which dimensions are critical to the vessel operation and be

more selective in assigning tolerances.

11. INSPECTION 11.1. MEANING

Inspection is the process of examining an object for identification or checking it for

verification of quality and quantity in any of its characteristics. It is an important tool for

ascertaining and controlling the quality of a product.

11.2. DEFINITION:

According to Springel and Lansburg, “Inspection is the process of measuring the qualities of

a product or services in terms of established standards”.

11.3. OBJECTIVES OF INSPECTION:

The main objective of inspection is to identify quality problems or deviation from standards

that have been set on the production of an output. The objectives of inspection are as follows:

1. MAINTAINANCE OF QUALITY:

The fundamental purpose of inspection is to maintain the quality of the product. This function

is performance by comparing materials semi-finished or finished products, men and machines

and tools with the established standards. Items which conform to the specification are within

the acceptable limits are accepted and other items are rejected.

2. IMPROVING THE PRODUCT QUALITY:

By comparing the quality of the products against the set standards, the defective items are

located and probable reasons for the defects are established. Necessary adjustments are done

for future by removing the reasons for defects and thus the quality of the product is improved

steadily and regularly. It helps in safeguarding the prestige and confidence of the organization

in the eyes of the customers.

3. REDUCTION IN COSTS:

As raw materials are inspected to see whether they are as per standards or not the defective

raw materials are thus not allowed to be used in production. Thus it saves the organization

from loss if any and reduces the costs of production.

11.4. TYPES OF INSPECTION:

There are two types of inspection

Cent percent inspection

Sample inspection

1. CENT PERCENT INSPECTION:

Cent percent inspection means, the inspection of each and every piece of store or material.

This type of inspection has the obvious advantage of giving complete assurance that all the

defective material has been eliminated from the inspected lot. However it has certain

drawbacks which make it unsuitable for certain situations. Since each piece is to be inspected

it proves very expensive and time consuming, particularly where large quantities are

involved. In the case of stores such as communications where inspection takes the form of

destructive tests 100% inspection is impossible as it would mean 100% destruction function it

is not generally realized that the assurance given by 100% inspection is not really complete.



This risks involved in cent percent inspection arises from human errors of failing to delete

defective articles due to the boredom and fatigue of repetitive inspection operations.

Controlled experiments on 100% inspection have shown that the percentage error is by no

means negligible.

Another serious criticism leveled against 100% inspection is that it appears to divert the

responsibility for the quality from the producer to inspector. Once a product has been

accepted after 100% inspection the producer tends to think that his responsibility regarding

its quality is over and if any defects are found in the product later on the inspector should be

answerable. It hardly needs to be said that it is the manufacturer who builds the quality or

lack of it into the product. The inspector may fail to delete a defective (assuming it is

detectable) but he certainly cannot add a defect in the product.

2. SAMPLE INSPECTION:

Any inspection procedure involving 100% inspection needs huge expenditure of time money

and labor expenditure on inspection is always considered as dead weight cost. Moreover due

to boredom and fatigue involved in the resistive inspection process there is always a

possibility to overlook some defective item even by most competent and efferent inspectors.

Also the nature of items may be such that these may be completely destroyed during the

process of inspection.

Example, life of a candle evidently in such cases 100% inspection cannot be planned.

The alternative is statistical sampling inspection methods. Here from the whole lot some

items are selected for inspection and decision regarding the quality of the whole lot is taken

on the basic of the sampled items. The items can be selected by various sampling methods.

Here the whole lot is accepted if the sample items conform to the specifications otherwise it

is rejected. Thus the sample items are considered to be the representatives of the whole lot.

The method of rejecting on accepting a lot on the basis of a sample is known as accepted

sampling or sampling inspection.

12. ACCEPTANCE SAMPLING:

Acceptance sampling is the process of inferring the quality of a large number of items a batch

or lot based on the quality of a small sample of the items. Acceptance sampling might be used

by a customer to evaluate the quality of incoming materials or by a producer to evaluate the

quality of outgoing product. With sample acceptance sampling select ‘n’ items from a batch

and test their quality. If the number of defective items in the sample is greater than some

specified level it means that the batch probably has an unacceptable number of defective

items and we reject it and we reject it and take some action.

EXAMPLE: Inspection all items in the batch or return it to the supplier. If the number of

defective items in the sample is less than or equal to the specified number the batch is

deemed to be of acceptable quality. The purpose is to determine with reasonable accuracy

whether the proportion of defects in a batch is greater than some acceptable proportion of

defects without having to test every item in the batch.



12.1. ACCEPTANCE SAMPLING PROCEDURE

The general steps of acceptance sampling are shown below.

12.2. ACCEPTANCE SAMPLING PROCEDURE:

Acceptance sampling is a statistical method that enables us to make accept or reject decision

based on a sample of items from the lot. After a lot is received a sample is selected for

inspection. The results of the inspection are compared to specified quality characteristics. If

the quality is satisfactory the lot is accepted and sent to production or shipped to customers. If

the quality is not satisfactory the lot is rejected mangers must then decide on the disposition

of the lot. In some cases the decision may be to keep the lot and remove the unacceptable or

non conforming items. In other cases the lot may be returned to the supplier at the suppliers

expenses the extra work and cost placed on the supplier can motivate the supplier to provide

high quality lots. Finally if rejected lots. Finally if the rejected lot consists of finished goods

the goods must be scrapped or reworked to meet acceptable quality standards.

The statistical procedure of acceptance sampling is based on the hypothesis testing

methodology. The null and alternative hypotheses are stated as follows.

Ho: good – quality lot

Ha: poor – quality lot

The figure shows the outcomes of the hypothesis testing procedure. The correct decisions

correspond to accepting a good quality lot and rejecting a poor quality lot.

Lot Received

Sample Selected

Sample Inspected for Quality

Results compared with specified quality characteristics

Accept the list

Send to Production

or Customer

Reject the lot

Decide on disposition

of the lot



STATE OF THE LOT

Ho true Ha false

Good – quality lot Poor – quality lot

Accept the lot

Decision

Reject the lot

12.3. OUTCOMES OF ACCEPTANCE SAMPLING:

However as with other hypothesis testing procedures we need to be aware of the possibilities

of making a type error (rejecting a good quality lot) or a type error (accepting a poor quality

lot).

12.4. TYPES OF ACCEPTANCE SAMPLING PLANS:

Many different sampling plans are used in practice. The difference among them is primarily

in the number of sample taken to evaluate a batch of items.

1. SIMPLE SAMPLING:

A sampling plan for a single sample is specified by two numbers N and C. The number of

items that should be included in a single random sample from a lot being inspected is the

sample size ‘n’. The acceptance number ‘c’ specifies the maximum number of defectives that

may be permitted in the sample if the lot is to be accepted. If the number of defectives found

in the sample is more than ‘c’ the entire lot will be rejected or inspected 100%.

If the number of defects does not exceed a specified acceptance number the consumer accepts

the entire lot. Any defects found in the sample are either repaired or returned to the producer.

If the number of defects in the sample is greater than c the consumer subject the entire lot to

100% inspection on rejects the entire lot and returns it to the producer. The single sampling

plan is easy to use but usually results in a large average of items in specter ANI than the other

plans.

2. DOUBLE SAMPLING:

The double sampling procedure consists of taking first a sample of size n, and inspecting it

for defectives. If the number of defectives is less than or equal to cut off number c, and then

accept the lot if they are more than C2, reject the lot. If the numbers of defectives are in b/w

C1 and C2 then take another sample of a different size n2. If the number of defectives in the

combined sample of n1+n2, is less than or equal to c2 accept the lot otherwise reject it.

3. SEQUENTIAL/MULITPLE SAMPLING PLAN:

A natural extension of the doubling sampling procedure is sequential sampling. A sample of

size ‘n’ is taken and based on cut off points. The decisions alternative is

1. To reject

2. To accept the lot and

3. To continue with one more sample. The samples are accumulate at each subsequent stage

and based on different cut of points at each stage a choice among the three decision

alternatives is made. The procedure is continued till a decision to either accept or reject the

lot is reached.

Correct Decision Type II Error (Accepting a Poor Quality lot)

Type I Error Correct Decision (Rejecting a good Quality lot)



12.5. ADVANTAGES OF ACCEPTANCE SAMPLING:

The advantages of acceptance sampling are as follows:

1. The items which are subjected to destructive test must be inspected by sampling

inspection only.

2. The cost and time required for sampling inspection is quite less as compared to 100%

inspection.

3. A problem of inspection fatigue which occurs in 100% inspection is eliminated.

4. Smaller inspection staff is necessary

5. Less damage to products because only few items are subjected to handling during

inspection.

6. The problem of monetary and inspector error introduced by 100% inspection is

minimized.

7. The lot of is disposed of in shorter time so that scheduling and delivery are improved.

8. The most important advantage of sampling inspection is that it exerts more effective

pressure on quality improvement. Since the rejection of entire lot on the basis of

sample brings much stronger pressure on quality improvement than the rejection of

individual articles.

12.6. DISADVANTAGES OF ACCEPTANCE SAMPLING:

The disadvantages of acceptance sampling are as follows:

Since the conclusion is based on a sample there is always some likelihood/risk of

making wrong influence about the quality of the lot. This is termed as producers risk

or consumer’s risk.

The success of the scheme depends on randomness of samples quality characteristics

to be tested lot size acceptance criteria etc.

13. CONTROL CHART:

A control chart is a statistical technique for controlling the quality of a product being

manufactured. It was first devised by Dr. WATTER A. SHEWART after whose name these

charts are also called stewart charts. In a relatively short period this technique of quality

control has found wide acceptance particularly in the USA and Europe.

A Control chart can be defined as a graphical representation of the collected information. The

information may pertain to measured quality characteristics or judged quality characteristics

of samples. It detects the variation in processing and warns if there is any departure from the

specified tolerance limits.

13.1. CHARACTERISTICS OF CONTROL CHARTS:

A Control chart is a time-ordered diagram to monitor a quality characteristics consisting of

A nominal value or centre line the average of several past samples.

Two control limits used to judge whether action is required, an upper control limit and

lower control limit.

Data points each consisting of the average measurement calculated from a sample

taken from the process ordered overtime. By the central limit thereon regardless of the

distribution of the underlying individual measurements the distribution of the sample

means will follow a normal distribution. The control limits are set based on the

sampling distribution of the quality measurement.



13.2. PURPOSE OF CONTROL CHARTS:

The purposes of using control chart are as follows:

A control chart indicates whether the process is in control or out of control.

It determines the process variability and defeats unusual variations taking place in a

process

It ensures product quality level

It warns in time and if the process is rectified scrap or percentage of rejection can be

reduced.

It provides information about the selection of process and setting to tolerance limits.

Control charts build up the reputation of the organization through customer

satisfaction.

13.3. TYPES OF CONTROL CHARTS:

If the quality characteristics are capable of quantitative measurement the control charts is

known as control chart for variables and if the quality characteristic Q cannot be measured

quantitatively. The control chart is known as control chart for attributes. The items can only

be classified as defective or non defective etc., Control charts are of two types.

Control charts for variables

Control charts for attributes

13.4. CONTROL CHART FOR VARIABLES:

Control charts based upon measurements of quality characteristics are called as control charts

for variables control charts for variables are often found to be a more economical means of

controlling quality than control charts based on attributes. The variables control charts that

are most commonly used are average or X-charts, range or R-charts and O-or standards

deviation charts.

The following situations can be encountered in practice.

The process may be in control

The mean of the characteristic is out of control but standard deviation is not for this

purpose control chart for means are prepared.

The standard deviation is out of control and not the mean. This is stupid by control

chart for range there range is the measure of variability because it can be easily

determined.

Both mean and standard deviations are out of control. This is studied by X and R

charts simultaneously.

13.5. CONTROL CHARTS FOR ATTRIBUTES:

Where the nature of product is such that the quality characteristic cannot be measured

quantitatively the items are classified on only defective and non defectives at the time of final

inspection. There can be a number of factors responsible for defining any item to be defective

and the separate record for each cause may be out of question.

The defects can be measured in any of the following two ways.

Number of defective items is taken in different samples here; P-chart on np-chart is

used.

Number of defects in one item in this case C-chart is use



CASE STUDY

Case Study 1:

The Orange bus company manufacture buses for different purposes. The Orange bus

objective is to provide expert, bespoke minibus conversions for Individual customers,

companies and charities. The corporate ethos of 'driving quality' focuses the company to

continuously look for improving the quality and effectiveness of its products and services.

This is demonstrated through high staff morale, increased sales and most importantly

satisfied customers. Although the Orange bus was already successfully measuring the quality

of its builds and processes informally, the company wanted to put in place a more formal

structure to improve operational efficiency and drive market share. The Orange bus decided

that a quality certificate would provide the ideal framework to achieve this.

Successful certification may enable the orange bus to gain national recognition as a quality

company which consistently builds a high quality product. The majority of motor

manufacturers insist on certification to this standard and the Orange bus has, subsequently

achieved national accreditation and approval from these manufacturers due to its outstanding

quality.

Auditing is performed monthly and continues to highlight opportunities for process

improvements. Non-conformities and corrective actions are religiously logged, enabling The

Orange bus to learn from mistakes and put in place initiatives to prevent recurrences of

problems. Now that the company monitors each stage of the vehicle build, preventive action

means that warranty costs have subsequently reduced. The management system also helps the

monitoring of customer feedback. As a result of this feedback, the company now offer a 36

month warranty which demonstrates firstly that they do listen to our customers, and secondly,

that they have confidence in the build quality of the product. The only other obstacle they

faced was helping staff understanding why they were implementing certification.

Questions:

a. Explain the quality tool that can be applied in the above case?

b. How will the employees access their role in quality management?

Possible Solutions:

a. Orange Bus should use ISO 9001 would provide the ideal framework to achieve.

Successful certification to ISO 9001 will enable Orange Bus to gain national recognition as a

quality company which consistently builds a high quality product. Since the majority of

motor manufacturers insist on certification to this standard, Orange Bus is now well prepared

for impending legislation within its subsidiary.

b. The employees should access the role in quality management by the following ways:

(i) Employees should act as a Facilitator:

It is the duty to assist employees in implementing quality management. As a employees, it is

the responsibility to select and appoint right individuals who can work as line managers and

take charge of the entire project. The employees, selected should ought to be reliable and

diligent and should be capable enough to handle a crucial project like total quality

management. It is the manager's responsibility to assign resources for total quality

management, allocate time for various training programs and appreciate employees who

come up with various improvement ideas and strategies which would help the organisation

deliver superior quality products.

(ii) Communication:



The employees should communicate the benefits of total quality management to all other

members of the Organization. Call employees on a common platform and address the benefits

and importance of total quality management. Make them understand how successful

implementation of total quality management programs would yield high quality products

which would not only benefit the organization but also the employees associated with the

same.

IMPORTANT QUESTIONS

1. Explain about Acceptance Sampling.

2. Discuss the techniques of work measurement

3. Explain the following

(i) Method Study

(ii) Job Design

(iii) Work Design

4. An Industrial Engineer has obtained the following data in connection with a time study on

the lines of the Hawthrone studies, taking four different elements and five cycle of the job

Element Cycle (1) Cycle (2) Cycle (3) Cycle (4) Cycle (5) Performance

Rating (%)

A 1.57 1.63 1.48 1.57 1.65 100

B 2.48 2.34 2.37 2.36 2.40 90

C 1.85 3.70 1.82 1.78 1.75 95

D 1.25 1.15 1.32 1.15 1.23 115

(i) Calculate the normal time for the job based on the above data.

(ii) Calculate the standard time for the job, if the permissible allowance is 25% of the normal

time.



http://b.com/


UNIT - 5 Materials Management BALAJI INSTITUTE OF IT AND MANAGEMENT

1

SYLLUBUS

(17E00206) OPERATIONS MANAGEMENT


Controlling aspects of a typical production and operations organization. Study understands the

concepts of work study and Quality management.




2. Facilities Management & Aggregate Planning: Location of Facilities, Layout of Facilities,

Optimization of Product/ Process Layout, Flexible Manufacturing and Group Technology:

Aggregate Planning – Preparation of Aggregate Demand Forecast, specification of

Organizational Policies For Something, Capacity Utilization, Determination of feasible




Production.






Issues in Materials Management - Functions - Activities - Selection of Materials - Advantages

of Materials Management.

Text Books:

Production and Operations Management, Aswathappa K - Himalaya Publishing House


References:



Science Press

Production and Operations Management, R.Panneerselvam: PHI Learning Private Ltd.



Wiley ...




Books



2

UNIT-5

MATERIAL MANAGEMENT

1. INTRODUCTION:

1.1. MEANING OF MATERIAL MANAGEMENT:-

The process of controlling the materials involved in the manaufacting

process of a product by a company is called as Material Management. Materials

are the most important part of a productive process. The costs of materials used

in manufacturing a product from a big part of the cost of finished product,

making their management vital to the manufacturing process. So, it can be

concluded that proper and orderly material management is very important for a

manufacturing concern.

1.2. DEFINITION OF MATERIAL MANAGEMENT:-

According to International Federation of Purchasing and Materials

Management, “Material Management is a total concept involving an

organizational structure unifying into a single responsibility, the systematic flow

and control of material from identification of the need through customer

delivery”.

Hence, Material Management is a term that includes all material related items,

(e.g., supply, procurement etc.,) that are virtual for manufacturing a particular

product. The forecasting and purchasing of raw material and manifesting

equipment with designs and valuation, together with planned procurement of all

materials that may include capital goods; packing materials; stock and storage

control; material handling and statistical analysis of all supplies.

2. OBJECTIVES:

OBJECTIVES OF MATERIAL MANAGEMENT:-

The objective of material management can be divided in two parts:

I. PRIMARY OBJECTIVES:-

The following can be seen as primary purposes of material management:

a. To procure raw materials at the best available price by adhering to

predetermined purchases policies.

b. To ensure optimum availability of raw materials so that the organism does

not run out of them or end up locking too many funds in storing them.

c. To minimum administration costs and other related activities while

procuring materials; and maintain enough stock required to fulfill demand.



3

d. To avoid running out of supply by continuously maintaining stock of

materials.

e. To ensure that materials meet set standards and quality demanded by users.

f. To make sure the workplace is not overstaffed and work is distributed

equally among workers.

II. SECONDARY OBJECTIVES:-

a. To work with the designed/ technical department to develop alternatives

for raw materials and products. This will increase the profit of a company.

b. To decided whether it will be economic to ‘make or buy’

c. To ensure quality of materials at all times.

d. To work towards continuous improvement of final product.

e. To improve cooperative among departments.

f. To follow reliable forecasting methods to calculate demand of materials.

3. IMPORTANCE/ADVANTAGES OF MATERIAL MANAGEMENT:

Material management has its own importance, some of them are:

a. Halting in the production process is minimized by ensuring constant

supply of materials.

b. Effective management of materials keeps purchasing and transportation

costs in control of the firm.

c. Wastage of materials is minimized through optimum stocking and effective

control.

d. By checking the quality of materials before purchasing them, the firm can

ensure its final product will not be rejected by customers.

e. All inputs are timely available.

f. Factors such as workforce, funds and equipment are used to their best.

g. Avoids blockages in stores throughout the production process.

h. Reduction in duplicated orders.

i. Improvements in overall plant availability for production.

j. Improved teamwork and relationship with production departments.

4. ISSUES IN MATERIAL MANAGEMENT:

The Challenges before managerial management in industry may be summed up

as follows:

1. Scare Capital for investing in material inventory

2. Difficulty in forecasting demand accurately

3. Increasing cost of land and storage space,

4. Selection of appropriate vendors

5. Optimizing time and quantity of demand for products

6. Managing information

7. Changes in Plan/Design



4

8. Changes in Schedule

9. Inclement weather

10. Lack of Coordination among laborers and site personnel

11. Lack of space to store materials at site

12. Shortage of materials during work

13. Increase in material cost

14. Delay in removal of debris causing inflation

15. Lack of funds for payment

16. Improper design specifications, drawings

17. Lack of space for movement of vehicles for unloading materials

18. Storing materials at wrong places

19. Damage of materials

20. Delay in payment for materials.

5. FUNCTIONS AND ACTIVITIES OF MATERIALS MANAGEMENT:-

Following are the major functions and activities of the material management:

1. MATERIAL PLANNING:

It is one of the basic functions of the material management to predict the

future requirement of the materials as per the requirement in the

manufacturing department. In order to ensure effective control, a material

budget is prepared for various departments and the standard performances

are compared with the actual and the deviations are further corrected.

Following are some of the issues that are tackled by material planning

a. The sales forecast of the translated for long term requirement of the

materials.

b. Considering the sales figures, a production plan is prepared and the

material is ascertained.

c. Arrangement is made for the facilities that are required for managing

the materials.

2. MATERIALS BUDGETING:

In finalizing material budget, there is notable contribution of the

personnel from the material management department. They provide the

relevant inputs that are required to frame the budget in a profitable manner.

The material budget is influenced by the strategic of the management

towards inventory control, policies affecting material quantities, change in

the cost structure etc. these functions are universal in nature and exist in

almost all type of organizations. On the other hand, certain relationship

exists in only specified organizations.



5

3. PRODUCTION CONTROL:

It can be achieved by;

a. Ascertaining the requirement of the material and the components to

be procured or manufactured.

b. Preparing schedule for the purchasing and the production process of

materials.

c. Placing order with the purchasing department and issue work advice

to the manufacturing department.

d. Dispatching the materials to productive department.

4. MATERIAL PURCHASING:

They are also responsible for procuring the material of the requisite quality

in order to satisfy the specification of the product at the minimum cost.

Following are the main activities under purchasing

a. Selecting a supplier and issuing purchase order.

b. To ensure that the delivery meets the requirement of materials.

c. To search for the alternatives to increases the profitability of the

company.

5. INVENTORY CONTROL OF MATERIAL:

It denotes a process of ensuring that the components are available to meet

the productive on time at the minimum cost. It covers:

a. Placing the order for the material at appropriate time.

b. Maintaining record of the material received, issued, in stock.

c. Deciding about the size that is to be ordered i.e. EOQ.

6. MATERIAL STOCKING:

It comprises of the following major functions;

a. Accepted the delivery of the materials that are ordered. Verification

of the material with purchase order and inspecting the ‘good

received note’. After all the compliances are done, forwarding the

same to the store department.

b. Proper storage of the material to ensure easy and faster retrieval.

c. Physical verification of the material at periodic interval and

correcting the deviations.

7. MATERIAL DISTRIBUTION:

It refers to distributing of material out of the department i.e. finished goods

and verifying the quantity

a. Receiving finished goods from production department. Verifying the

same and storing the same till the time they are distributed properly.



6

b. Packing and labeling of the finished goods and making them ready

for the delivery.

c. Preparation of shipping documents like bill of material, packing slip,

lorry receipt, railway receipt which are required to be forwarded

along with the shipment.

d. Reporting the shipment to the accounts department so that the bill

can be issued to the customer and copy can be forwarded to the sales

department and the order can be closed.

8. MATERIAL HANDLING:

It includes

a. Handling the material through adequate pallets, trucking, containers

etc.

b. Arranging various material handling equipment and other allied

items.

9. TRAFFIC:

It is basically related with managing the inflow and the outflow of the

materials. It initialize with receiving material and after that dispatching the

same. In case, the company intends to maintain its own network of the

traffic fleet or in case the services are hired as part of routine, there can be

altogether a distinct function. It covers:

a. Carrying raw material from the supplier’s destination, railway

offices and other destinations.

b. Carrying finished goods towards the customers, railway offices and

other destinations.

c. Administration of the transport route and fares.

d. Maintaining fleet of the delivery vehicles, if the ownership of the

same lies with the company.

6. SELECTION OF MATERIAL:-

For the selection of material for the product, production manager must

have sound knowledge of material and their properties, so that he can select

appropriate materials for his product. Research on materials is necessary to find

alternatives to satisfy the changing needs of the design in the product and

availability of material resumes.



7

6.1. PROCESS IN MATERIALS SELECTION:

Following steps should be taken in the selection of materials for the product:

1. ANALYSIS OF MATERIAL PERFORMANCE REQUIREMENT:

Analysis of material performance requirement can be done by the initial

screening technique.

This technique use the critical requirement each part to define the

performance requirements of the material. Start with all materials available

and narrow down the choices on the basis of the rigid requirements.

2. CREATING ALTERNATIVE SOLUTIONS AND PROCESS OF

SOLUTIONS FOR THE OPTIMUM CONCEPT:

Having specified the material requirements, the rest of the selection

process involves the search for the material that would best meet those

requirements.

The starting point is the entire range of engineering materials.

At this stage, it is essential to open up channels in different directions.

Steel may be the best material for one design Concept while a plastic is

best for a different concept, even though the two designs provide similar

functions.

This importance of this phase is that it creates alternatives without much

regard to their feasibility.

3. EVALUATION OF ALTERNATIVE SOLUTIONS:

Use soft material requirements to further narrow the field of possible

materials a few optimum candidates.

4. DECISION ON THE SELECTION OF OPTIMUM SOLUTION:

Use the optimum materials and matching manufacturing processes to make

Detail designs.

Compare alternative combinations taking into account the elements of cost.

Select optimum combination of Design – material – manufacturing

process.

Process in Materials Selection

Analysis of the

performance

requirements

Evaluation of Alternative

solution

Creating Alternative

solutions and process

solutions for the

optimum concept

Decision on the Selection

of Optimum Solution



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6.2. FACTORS CONSIDERED IN THE SELECTION OF MATERIALS:

Following factors are considered in the selection of materials:

1. AVAILABILITY: -

The material should be readily available in market in large enough quantities to

meet the requirement.

2. COST:-

For every application, there is limiting cost beyond which the designer cannot go.

When the limit exceeded the designer has to consider an alternative material. In

cost analysis, there are two factors namely cost of material and the cost of

processing the material into finished goods. It is likely that the cost of material

might be low but the processing may involve costly machining operations.

3. MECHNICAL PROPERTIES:-

The important mechanical properties of material from the consideration design

are strength, rigidity, toughness, resilience, shock resistance, wear resistance,

creep characteristic, corrosion resistance, frictional properties and hardness.

These properties are further explained as

a. Strength: the ability of material to withstand stress without fracture is

called its strength.

b. Ductility: the property of a material to undergo deformation under tension

without fracture is called ductility.

c. Hardness: the ability of a material to withstanding scratching, wear and

abrasion or indentation (penetration) by harder bodies is known as

hardness.

d. Toughness: toughness is the amount of energy that a material can absorb

before it fractures.

e. Resilience: it is the capacity of a material to absorb or store energy up to

elastic limit, and to resist shock and impact.

f. Creep: The slow and progressive deformation of a material with time at

constant stress is called creep.

g. Corrosion Resistance: it is the deterioration of a material by chemical

reaction with it environment.

h. Brittleness: The property of a material by virtue of which it will be

fractured without appreciable deformation is called brittleness.

i. Weldability: It is defined as the ease with which a material can be welded

under a given set of conditions.

Manufacturing Consideration: It is important consideration in selection of

materials. Sometimes, expensive materials are more economical than low cost

material, which difficult to machine.



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IMPORTANT QUESTIONS

1. Define Materials Management. What are the Objectives of Materials

Management?

2. Discuss the functions and activities of Material Management

3. Explain the selection of materials. What process is involved in the selection of

material?

4. Briefly discuss the factors considered in the selection of materials

5. Enumerate the advantages and issues in Materials Management?



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BALAJI INSTITUTE OF I.T AND MANAGEMENT KADAPA MERGED PDF -LAST-2.5 UNITS.pdf · Modern Production/Operations Management, Elwood S.Buffa and Rakesh K Sarin, Wiley ... Production and