1.0 INTRODUCTION
In this note,
you will learn that methods analysis and motion study techniques are often used to develop the
"efficiency" aspects of job. However they do not directly address their behavioural aspects.
Nonetheless, they are important part of
job design, as well as the efforts being made to
increase productivity
through different means.
2.0 OBJECTIVES At
the end of this note, you should be able to:
i. Explain the importance of work methods analysis
ii. Demonstrate the ability to develop a questioning
attitude about every aspect of a
particular job to be studied
iii. Explain the steps usually followed by job analysis
iv. Explain who a job analyst is v. Demonstrate how to use motion study in the
performance of human activities vi. Demonstrate the ability to use flow
diagrams and process charts.
3.0 MAIN CONTENT
3.1 Introduction to Work Methods Study It is usual for job design to begin with
a methods analysis of an overall
operation. It then moves from general to specific details of the job
by concentrating on arrangement of the
workplace and movements of the worker.
The need for methods analysis can come from a number of different
sources, such as:
(a) Changes in tools and equipment
(b) Changes in product design, or new products
(c) Changes in materials or procedures
(d) Government regulations or contractual agreements
(e) Other factors (e.g. accidents, quality problems)
In our treatment of Productivity and Human Behaviour under
Note 15, we referred to Figure 15.1,
showing the various variables affecting labour
productivity. From that figure, you were able to see that the machines,
tools, materials, and work methods used
by workers directly affect labour
productivity. How do we go about improving work methods? It might be
better to start with workers themselves.
This is because they are the people who do
the jobs daily, and on things related to these jobs. In a way, they are
experts in their own rights. You should note that the main objective of
improving work methods is to increase
productivity by increasing the production capacity of an operation or group of operations, reducing the cost of the
operations, or improving product
quality. One important approach
to successful methods analysis is the development of a questioning attitude about every aspect of
the job being studied. Such relevant
questions will include the following:
i. Why is there a delay or storage at this point?
ii. How can travel distances be shortened or avoided? iii. Can materials handling be reduced? iv. Would a re-arrangement of the workplace
result in greater efficiency? v. Can
similar activities be grouped? vi. Would
the use of additional or improved equipment be helpful? vii. Does the worker have any ideas for
improvement? viii. Who else could do it
better? Questions such as these will
ensure that analysts accept nothing in an operation as sacred, i.e. everything about the job will
be meticulously scrutinized.
3.2 Steps Involved in Conducting Work Methods Works analysis can be done both for
existing jobs and jobs that have not yet
been performed. It might seem strange to you that we are talking
about analysing methods of nonexisting
jobs! Yet, it is important to establish a
method for a new job, instead of allowing the job to start and then try
to improve it later. For an existing job, the procedure usually is
to have the analyst observe the job as
it is currently being performed, and then device improvements. For a new job however, the analyst must rely on a job
description and an ability to visualise
the operation in advance. Gaither (1996)
lists ten steps that are generally followed by methods analysts:
i. Make an initial investigation of the operation under
consideration
ii. Decide what level of analysis is appropriate
iii. Talk with workers, supervisors, and others who are
familiar with the operation. Get their
suggestions for better ways to do the work.
iv. Study the present method. Use process Charts, time
study, and other appropriate techniques
of analysis. Thoroughly describe and evaluate the present method
v. Apply the questioning attitude, the principles of motion
economy, and the suggestions of others.
Device a new proposed method by using
process charts and other appropriate techniques of analysis.
vi. Use time study, if necessary. Compare new and proposed
methods. Obtain supervisors' approval to
proceed.
vii. Modify the
proposed method as required after reviewing the details with workers and supervisors.
viii. Train one or more workers to perform the proposed
method on a trial basis. Evaluate the
proposed method. Modify the method as required.
ix. Train workers and install the proposed method.
x. Check periodically to ensure that the expected savings
are being realised. In performing work methods analysis, certain
diagrams and charts can be useful. These
include flow-process charts and worker-machine charts.
3.2.1 Flow-Process Charts
Flow diagrams and process charts are about the most
versatile techniques available for
analysing work
methods. They are usually used together to eliminate or reduce delays, eliminate or
combine tasks, or reduce travel time or
distance. Table 16.1 shows and describes widely applied flowcharting
symbols. Of the five, only the operation
symbol denotes a value-adding activity. The
other symbols reflect an addition of cost not value.
Table 16.1: Flow Chart Symbols
Figure
16.1 shows how an improvement team might document a company's travel authorisation process. The before
version, i.e. part A, has eight valueadding
operations, five transportations, two inspections, and three delays.
The streamlines version in part B uses
personal computer communication by e-mail.
It thus cuts the operations to five, transportation to two, inspections
to one (combined with an operation), and
delays to one. You should, however, note
that the reduction from eight to five does not mean less value, since
valueadding operations also consume costly resources and time. The end result
is a simpler process that does the
job. For worked examples on this
discussion please refer to Dennis C. Kinlaw
(1992) Continuous Improvement and Measurement for Total Quality
(Burr Ridge, III, Business One Irwin,
1992), pp. 214-215.
Figure
16.1 shows how an improvement team might document a company's travel authorisation process. The before
version, i.e. part A, has eight valueadding
operations, five transportations, two inspections, and three delays.
The streamlines version in part B uses
personal computer communication by e-mail.
It thus cuts the operations to five, transportation to two, inspections
to one (combined with an operation), and
delays to one. You should, however, note
that the reduction from eight to five does not mean less value, since
valueadding operations also consume costly resources and time. The end result
is a simpler process that does the
job. For worked examples on this
discussion please refer to Dennis C. Kinlaw
(1992) Continuous Improvement and Measurement for Total Quality
(Burr Ridge, III, Business One Irwin,
1992), pp. 214-215.
3.2.2 Worker-machine Chart A worker-machine
chart is helpful in visualising the portions of a work cycle during which an operator and equipment are
busy or idle. The analyst can easily see
when the operator and machine are working independently, and when their work overlaps or is
interdependent. One area in which this type of
chart is useful is in determining how many machines or how much
equipment the operator can manage.
3.3 Motion Study Motion study is the
systematic study of human motions used during the performance of an operation. The purpose is
to eliminate unnecessary motions and to
identify the best sequence of motions for maximum efficiency. In this regard therefore, motion study can be an
important avenue for productivity
improvements. The present practice of motion study can be traced to the
work of Frank Gilbreth, who originated
the concept in the bricklaying trade in the
early 20th century. There are a
number of different techniques that motion study analysts can use to develop efficient procedures. We will only
review motion study principles and
micromotion study here.
3.3.1 Motion study principles
Gilbreth's work laid the foundation for the development of motion
study principles, which are guidelines
for designing motion-efficient work
procedures. The guidelines are divided into three categories: principles
for use of the body, principles for
arrangement of the workplace and principles for the design of tools and equipment. These
principles are listed in Table 16.2.
Table 16.2: Motion Study Principles
1. Finger motions.
2. Finger and wrist motions.
3. Finger, wrist, and lower arm motions.
4. Finger, wrist, lower arm, and upper arm motions.
5. Finger, wrist, lower arm, upper arm, and body motions.
6. Work done by the feet should be done simultaneously with work
done by the hands. However, it is
difficult to move the hand and foot
simultaneously.
7. The middle finger and the thumb are the strongest. The use of
the human body:
(a.) Both hands should begin and end their basic divisions of accomplishment simultaneously and should not
be idle at the same instant, except
during rest periods.
(b.) The motions made by the hands should be made symmetrically
and simultaneously away from and toward
the center of the body.
(c.) Momentum should assist workers wherever possible and should
be minimized if it must be overcome by
muscular effort.
(d.) Continuous curved motions are preferable to straight-line
motions involving sudden and sharp
changes in direction.
(e.) The least number of basic divisions should be used, and they
should be confined to the lowest
practicable classifications. These classifications, summarized in ascending order of the time
and fatigue expended in their
performance are: working fingers. The index finger, fourth finger,
and little finger are not capable of
handling heavy loads over extended
periods.
8. The feet are not capable of efficiently operating pedals when
the operator is in a standing
position.
9. Twisting motions should be performed with the elbows bent.
10. To grip tools, workers should use the segments of the fingers
closest to the palm of the hand.
The arrangements and conditions of the workplace.
1. Fixed locations for all tools and material should be provided
to permit the best sequence and to eliminate
or reduce the therbligs search and
select.
2. Gravity bins and drop delivery should reduce reach and move
times, wherever possible, ejectors
should remove finished parts automatically.
3. All materials and tools should be located within the normal
working area in both the vertical and
the horizontal planes.
4. A comfortable chair for the operator and the workstation's
height should be arranged so that the
work can be efficiently performed by the
operator alternately standing or sitting.
5. Proper illumination, ventilation, and temperature should be
provided.
6. The visual requirements of the workplace should be considered
so that eye fixation demands are
minimized. 7. Rhythm is essential to the
smooth and automatic performance of an
operation, and the work should be arranged to permit an easy and
natural rhythm wherever possible.
The design of tools and equipment
1. Multiple cuts should be taken whenever possible by combining
two or more tools in one or by arranging
simultaneous cuts from both feeding
devices, if available (cross slide and hex turret).
2. All levers, handles, wheels, and other control devices should
be readily accessible to the operator
and designed to give the best possible
mechanical advantage and to utilize the strongest available muscle group.
3. Parts should be held in position by fixtures.
4. The use of powered or semi automatic tools, such as power nut
and screwdrivers and speed wrenches,
should always be investigated. .
In developing work methods that are motion-efficient, the analyst
tries to:
1. Eliminate unnecessary motions
2. Combine activities
3. Reduce fatigue
4. Improve the arrangement of the workplace
5. Improve the design of tools and equipment
3.3.2 Micromotion Study Frank Gilbreth and
his wife, Lilian (an industrial psychologist) were also responsible for introducing motion pictures
for studying motions, called micromotion
study. Apart from its direct application
in the industry, micromotion study is now
useful in other human endeavours such as sports and health care. The use
of video camera and slow-motion replays
enable analysts to study motions that
would otherwise be too rapid to see. Today, it is a most important tool
in sports administration, coaching, and
arbitration in disputed competitions. It is also increasingly being used to analyse crimes.
One other important advantage of
micromotion study is that the resulting films provide a permanent record
that can be referred to, not only for
training workers and analysts, but also for
settling job disputes involving work methods.
4.0 CONCLUSION The best way to
improve work methods is to start with workers. This is because they are the people who do the jobs daily,
and on things related to these jobs. The
main objective of work methods is to increase productivity by increasing the production capacity of an operation or
group of operations, reducing the cost
of the operation or improving product quality.
5.0 SUMMARY Methods analysis and
motion study techniques are often used to develop the "efficiency" aspects of jobs.
However, they do not address their behaviour
aspects. In spite of this, they are some important parts of job design.
Working conditions are also important
aspects of job design, not only because of the
behavioural and efficiency factors, but also because of concern for the
health and safety of workers.
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