operation management

1. WORK
MEASUREMENT
Saravanan J

2. INTRODUCTION
• Work measurement is the application of techniques designed
to establish the time for a qualified worker to carry out
specified jobs at a defined level of performance.
• We have seen how total time to manufacture a product is
increased by:
adding undesirable features to product,
bad operation of the processes, and
ineffective time added because of worker and management.
• All this leads to decreased productivity.

3. INTRODUCTION
• Method study is one of principal techniques by which
work content in the product manufacture or process
could be decreased.
• Method study is, then, a technique to reduce the work
content mainly by eliminating unnecessary movements
by workers and/or materials and/or equipments.
• However, even after that, there could be substantial
unnecessary time taken for the process because of lack
of management control and/or inaction of worker.

4. INTRODUCTION
• Work measurement (WM) is concerned with
investigating, reducing and eliminating ineffective
time, whatever may be the cause.
• WM is the means of measuring the time taken in the
performance of an operation or series of operations in
such a way that the ineffective time is shown up and
can be separated out.
• In practice, proving existence of the ineffective time
is the most difficult task.
• After existence is proved, nature and extent is easy to
see!

5. INTRODUCTION
• WM is also used to set standard times to carry out the
work, so that any ineffective time is not included later.
• Since, standard times are set for all the activities
through WM, it has earned bad reputation amongst
workers.
• Major reason for that has been the initial focus of the
WM methods, which essentially targeted only the
worker controllable ineffective times.
• Management controllable ineffective times were ignored
traditionally.

6. INTRODUCTION
Two critical issues in work study:
1. Method study should precede the work
measurement, always.
2. Elimination of management controllable ineffective
time should precede the elimination of the
ineffective time within the control of the workers.

7. OBJECTIVES OF WM
• To determine the standard cost and as an aid in
preparing budgets.
• To balance the crew activities and those jobs
requiring several workers.
• To determine scheduling and planing work.
• To determine effectiveness of the machine.
• To balance production lines for new models or new
products.
• To make cost estimate of new products.

8. OBJECTIVES OF WM
• To determine time standards to be used for providing
a basis for wage incentive plans.
• To determine time standards to be used for providing
a basis for labour cost control.

9. COMPONENTS OF WM
• Element - An element is distinct part of specified job
selected for convenience of observation, method and
analysis
• Performance rating- Rating speed of the operator is
matter of judgement on the part of time study
analyst .
• Allowance - It's time allow the worker to recover
from fatigue and to attend the personal needs.
• Standard time - The time consumed from an avg
worker, at an avg speed, under normal working
conditions.

10. COMPONENTS OF WM
ELEMENT
• A repetitive element is an element which occurs in
every work cycle of the job.
• An occasional element does not occur in each work
cycle of the job, but which may occur at regular or
irregular intervals. e.g. machine setting.
• For a constant element, the basic time remains constant
whenever it is performed. e.g. switch the machine on.
• A variable element is an element for which the basic
time varies in relation to some characteristics of the
product, equipment or process, e.g. dimensions, weight,
quality etc. e.g. push trolley of parts to next shop.

11. COMPONENTS OF WM
• A manual element is an element performed by a
worker.
• A machine element is automatically performed by a
power-driven machine (or process).
• A governing element occupies a longer time than any
of the other elements which are being performed
concurrently. e.g. boil kettle of water, while setting out
teapot and cups.
• A foreign element is observed during a study which,
after analysis, is not found to be necessary part of the
job. e.g. degreasing a part that has still to be machined
further.

12. COMPONENTS OF WM
PERFORMANCE RATING
observed performance
performance rating = x 100
standard performance

13. COMPONENTS OF WM
ALLOWANCE
• In addition to including relaxation allowances, short rest pauses
could be added over the period of work for an operator.
• Start-up / shut-down allowance
• Cleaning allowance
• Tooling allowance
• Set-up / change-over allowance
• Reject / excess production allowance
• Learning / training allowance
• Policy allowance is an increment, other than the bonus
increment, applied to standard time to provide a satisfactory
level of earning for certain level of performances under
exceptional conditions.

14. COMPONENTS OF WM
STANDARD TIME
NORMAL (OR) BASIC TIME =
RatingStandard
RatingObserved
timeObserved x
STANDARD TIME = NORMAL TIME +ALLOWANCE

15. TECHNIQUES FOR WM
• Time study
• Synthesis from standard data
• Pre-determined motion time system [PMTS]
• Analytical estimating
• Work sampling

16. TIME STUDY
1. Recording the times and rates of working for the
elements of a specified job carried out under specified
conditions,
2. Analyzing the data so as to obtain the time necessary
for carrying out the job at a defined level of
performance.

17. STEPS IN TIME STUDY
• Break the job elements.
• Record the observed time for each elements by means
of different techniques.
• Establish elemental time values by extending
observed time into normal value for each element by
applying a rating factor.
• Assess relaxation allowance for personal needs ,
physical and mental fatigue invloved in carrying out
each element.
• Add contigency allowance , if any , to arrive at the
standard time to do the job.

18. STEPS IN TIME STUDY
Observed time
Normal time
Work content
Standard time
applying
rating factor
add relaxation
allowance
add contigency
and other
allowances
required

19. SYNTHESIS FROM STANDARD DATA
• In many industries , repetitive nature are used in batch
production, in these cases we can use synthesis technique.
• In this synthesis use standard time is computed by adding
various elemental times which constitute the work.
• Standard data are made available for the most known
elemental operations like preparing ,setting , manipulating,
removing, clearing,holding and tightening.

20. PMTS
• It's defined as a WM technique by which normal or basic
times are establishes for human motions and these time
values are used to build up a time for a job at defined level
of performance.
• It involves thinking or observing through a job , recording
job elements, recording pre established motion units and
calculating performance standard.
• It's an improvement over motion study , its affording
detailed motion analysis , it make to set a measure of time
thata series of motion ought to take

21. ANALYTICAL ESTIMATING
• It's used to determine the time values for jobs,having long
and non- reptitive operations .
• Time values detemined by using synthetic data , if synthesis
data in not available.
• Estimator shoud have adequate experience of estimating,
motion study, time study and use of standard data.

22. WORK SAMPLING
• It's a technique of WM , its does not involve stopwatch
measurement , as do many of other technique;
• Instead , its based on simple random sampling techniques ,
derived from statistical sampling theory,
• Work sampling known by follwing names :
1.active sampling
2.ratio delay
3.snap reading and observing
• Purpose of sampling is to estimate at what proportion of a
worker's time is devoted to work activities

23. USES OF WM
• To compare the efficiency of alternative methods.
Other conditions being equal, the method which takes
the least time will be the best method.
• To balance the work of members of teams, in
association with the multiple activity charts, so that,
as far as possible, each member has tasks taking an
equal time.
• To determine, in association with man and machine
multiple activity charts, the number of machines an
worker can run.