2. Work Study
• Systematic examination of the method
of carrying out an activity so as to
– Improve the existing method of doing the
job, called method study, and
– To set up standards of performance ,
called work measurement
With the objective of improving the
productivity
3. Work Study - Objectives
• To recommend and implement the desired
improvement in work methods by establishing the
most economical way of doing things
• Investigation and analysis of existing situation
• Examination of weaknesses if any in the production
process
• Most effective use of the existing or proposed plant
• Efficient use of human efforts
• Ensure proper performance of those employed in the
production process
4. Work Study - Objectives
• Measurement of work values
• To initiate and maintain incentive bonus schemes
• Setting standards for labor cost and originating labour
cost control documentation
• To standardise the method, material and equipment
used in the production process
• To determine the time required by an ideal operator
to perform the task at some desired level of
performance
5. BASIC WORK CONTENT
POOR DESIGN AND FREQUENT CHANGES
WASTE OF MATERIALS
POOR LAYOUT AND UTILISATION OF SPACE
INADEQUATE MATERIAL HANDLING
WORK CONTENT ADDED
DUE TO INEFFICIENT
METHODS OF
MANUFACTURE OR
OPERATION
FREQUENT STOPPAGES AS PRODUCTION
CHANGES FROM ONE PRODUCT TO
ANOTHER
INEFFECTIVE METHOD OF WORK
POOR PLANNING OF INVENTORY
FREQUENT BREAKDOWNS OF MACHINES
AND EQUIPMENT
WORK CONTENT ADDED
DUE TO HUMAN
FACTORS
ABSENTEEISM AND LATENESS
POOR WORKMANSHIP
ACCIDENTS AND OCCUPATIONAL HAZARDS
TOTAL WORK CONTENT
TOTAL WORK CONTENT
WORK CONTENT ADDED
DUE TO POOR
PRODUCT DESIGN OR
MATERIAL
SPECIFICATION
6. WORK STUDY
WORK STUDY
METHOD STUDY
WORK MEASUREMENT
TO IMPROVE METHODS
OF PRODUCTION
TO ASSESS
EFFECTIVENESS OF
WORKERS
RESULTING IN MORE
EFFECTIVE USE OF
MATERIALS, MANPOWER,
PLANT & EQUIPMENT
MAKING POSSIBLE IMPROVED
PLANNING & CONTROL,
MANNING & AS A BASIS FOR
SOUND INCENTIVES
HIGHER PRODUCTIVITY
7. Method Study
• Systematic investigation i.e. recording &
critical examination of the existing method of
doing a job in order to
– Develop and install an easy, rapid,
efficient, effective & less fatiguing
procedure
– Develop a more economic method
For doing the same job
8. Work Measurement
• Application of different techniques to measure
and establish time required to complete the
job by a qualified worker at a defined level of
performance
• Objectives
– Reveals excess work content in any operation
– Can be used to look into cause and take steps to
reduce ineffective time
– Set standard time for the work
9. Method Study - Procedure
• Select and define
– Economic (cost) benefit is the main criteria
• Record
– Recording/ collection of necessary information
•
•
•
•
Movement of equipment or material
Clerical procedure involved in the job
Work done by an operator
Movement of operator with respect to machines and other
operations, etc.
• Examine critically the existing method
– Each activity critically examined after recording all
relevant information about the same (for value /
non value adding )
10. Method Study - Procedure
– Two sets of detailed questions are asked
• To indicate facts and the reasons underlying
• To indicate alternatives and means of
improvements
– Brain storming and creative thinking session
• . Develop
and evaluate the best method
– Record method proposed
– Consult management & workers for their
suggestions
– Workout cost of installing new method
– Prepare new flow process chart
– Put up report for management approval
11. Method Study - Procedure
•
Define the new method
– Management and workers to be familiarised with the
new method and written standard practice report
prepared
• Install
– Properly plan and implement the new method
– Do trial runs to remove snags till it works smoothly
• Maintain
– Once installed, the new method to be maintained
– Verify proper functioning through periodic checks /
verifications
12. Method Study - Techniques
• Various techniques used are
– Charts
•
•
•
•
•
Outline process charts
Flow process charts: man, material, equipment types
Two handed process charts
Multiple activity chart
Travel chart
13. PROCESS CHARTS
A chart / diagram giving an overall view of the process :
activities represented by symbols
OPERATION
STORAGE
DELAY OR TEMPORARY
STORAGE
TRANSPORT
INSPECTION
OPERATION CUM
TRANSPORT
OPERATION CUM
INSPECTION
14. Method Study - Procedure
– Diagrams
•
•
•
•
Flow
String
Cyclegraph
Chronocycle graph
– String diagram
• String strung to follow path taken by material
• Deals to solve complex movement & plant layout
15. Method Study - Procedure
– Cycle graph
•
•
•
•
Introduced by Gilberth
Photographic method
Very accurate
Used for recording very fast movement not possible for
seeing by eye
– Chronocycle graph
• Light source 10-20 times per second records the path of
movement in the form of pear shaped spots on the plate
– Motion and film analysis( micro motion & memo
motion studies)
• Simultaneous motion (Simo) chart
• Pre-determined motion time system (PMTS)
16. Method study - Procedure
– SIMO chart
•
•
•
•
Used for micro motion studies
Time in terms of winks
Very accurate for detailed analysis
1 wink ≅ 1/2000 of a minute
17. Work Measurement - Objectives
• Target time for each job can be estimated
scientifically
• Sound comparison of alternative methods can be
made by comparing their basic times
• Useful incentive schemes can be generated by
linking these target times
• Variance between actual time and the target time can
lead to apply better control on the operations
• It can lead to proper balancing of the work distribution
• Forecast for future manpower and related costs can
be made
18. Work Measurement - Steps
• Select the job to be measured
– Decision mostly based on increasing productivity
• Break job into operations / elements
• Determine number of observations to be
timed
• Measure with a timing device and record on
time study form
– Time study is a work measurement technique for
recording the times and rates of working for the
elements of a specified job
• Compute Observed time
19. Work Measurement - Steps
• Calculate Normal (Basic) time by using
Performance Rating Factor
• Add process allowance, rest and personal
allowance and special allowances to Normal
(Basic) time to obtain Standard time
• Define the new method
• Install the new method as agreed standard
procedure with the standard time allowed
• Maintain the new standard practice
20. Time Estimates and Production
Standards
• Standard Time
– Time required to complete a unit of work
• Under existing working condition
• Using specified method & machine
• By an operator able to work in a proper manner
and at a standard pace
21. Time Estimates and Production
Standards
• Basic time
– Time required to perform a task by a Normal
Operator working at a standard pace (rate) with no
allowance for personal delays, unavoidable delays
or fatigue
– Basic / Normal (time) =
Observed time *
Observed rating of operator / Standard rating ( i.e.
100 )
22. Time Estimates and Production
Standards
• Allowances
– Personal allowances
• For visiting toilets, drinking water etc
– Fatigue / relaxation allowance
– Delay allowance
• For tool breakage, interruption by foreman etc
– Typically
• Personal allowance : 2-5 % per day
• Fatigue : 12-20% of normal time
23. Time Estimates and Production
Standards
• Performance rating
– Indicates gauging and comparing the pace rate of
the performance of a worker against a standard
performance level set by time study engineer
– Rating Factor is the leveling factor
– Generally 0-100 % standard rating scale is the
best and has been adopted by British Standard
24. Time Estimates and Production
Standards
• Standard time calculation
– Standard time for an operation will be the sum of
the standard times for all the elements of which it
is made of.
– Expressed in standard minutes or hours
• Standard time = Basic time + Allowances
– Basic (Normal time )= Observed time * Observed
rating of operator / Standard rating
– Observed time is the time observed by stopwatch
25. Performance Rating
OBSERVED TIME
BASIC TIME
BONUS
ALLOWANCES
STANDARD TIME
POLICY ALLOWANCE
INTERFERENCE ALLOWANCE
DELAY ALLOWANCE
RATING FACTOR
RELAXATION ALLOWANCE
TIME ISSUED FOR PAYMENT PURPOSES
26. Work Measurement - Techniques
• Time study
– Stop watch procedure
• Work sampling
• Pre-determined Motion Time Systems (PMTS) or
Elemental Motion Time Systems ( EMTS ) or
Basic Motion Time Systems (BMTS ) ( work factor
and M-T-M systems )
• Structured estimation
– Analytical estimation
– Comparative estimations
27. Time Study - Procedure
• Most widely used and involves
– Recording the time for performing a certain job /
its elements under specified conditions
– Analyse data
– Obtain time necessary for an operator for the job
at a defined performance rate
• Steps-preliminary
– Identify job and operation to be timed
– Use improved procedure
– Select worker and brief him and his superior about
study
– Collect equipments, arrange machine, jigs ,
fixtures etc
28. Work study- advantages
•
•
•
•
•
•
•
•
•
Uniform & improved production flow
Higher productive efficiency
Reduced manufacturing cost
Fast & accurate delivery dates
Better employee-employer relations
Better service to customers
Job security & job satisfaction to workers
Better working & other conditions
Higher wages to workers
29. Work Study - Limitations
• Always looked upon by the supervisor &
workers or unions with suspicion
• Sudden change is not appreciated
30. References
•
•
•
•
Production Operations Management : Dr. B. S. Goel
Work Study (Motion & Time Study) : O.P.Khanna
Productivity Techniques : Gondhlekar / Salunke
Production and Operations Management :
Aswathappa / Bhat
33. WORK SAMPLING
• TECHNIQUE IN WHICH
– LARGE NUMBER OF OBSERVATIONS ARE
MADE OVER A PERIOD OF TIME OF ONE OR A
GROUP OF MACHINES, PROCESSES OR
WORKERS
– RECORD WHAT IS HAPPENING AT THAT
INSTANT
• PERCENTAGE OF OBSERVATIONS RECORDED
FOR A PARTICULAR ACTIVITY OR DELAY IS A
MEASURE OF THE PERCENTAGE OF TIME
DURING WHICH ACTIVITY OR DELAY OCCURS
34. PRE-DETERMINED MOTION TIME SYSTEM
(PMTS)
• PRE-DETERMINED TIME STANDARD IS A WORK
MEASUREMENT WHEREBY TIMES ESTABLISHED FOR
BASIC HUMAN MOTIONS ( CLASSIFIED AS PER THE
NATURE OF THE MOTIONS AND CONDITIONS UNDER
WHICH THESE ARE MADE ) ARE USED TO BUILD UP THE
TIME FOR THE JOB AT A DEFINED LEVEL OF
PERFORMANCE ( B.S. 3138: 1969 )
• MACROMOTION TIME MEASURED IN SEVERAL SECONDS
• MICRO MOTION –ELEMENTS OF THE JOB ARE BASIC
HUMAN MOTION WITH DURATION OF 0.1 SECONDS AND
LESS
• OPERATIONS ARE RECORDED ON A MOVIE FILM
35. METHOD TIME MEASUREMENT
(M-T-M )
• M-T-M ASSOCIATION GOT RECOGNITION IN 1948
• BASIC HUMAN MOVEMENTS ARE ANALYSED IN
MORE DETAILS
• TIME MEASURED IN TERMS OF TMUs (TIME
MEASUREMENT UNITS)
• 1 TMU = 0.0006 MINUTES
36. STRUCTURED ESTIMATION
• A TECHNIQUE WHICH USES PAST DATA TO PREDICT
FUTURE VALUES
• STEPS INVOLVED ARE:
– BREAK THE JOB INTO ELEMENTS
– USE STANDARD DATA TO GET TIME VALUES OF ELEMENTS
FOR WHICH SUCH INFORMATION IS AVAILABLE
– MEASURE THE TIME VALUES OF ELEMENTS WHICH ARE
WORTH THE EFFORT
• TECHNIQUE IS A COMBINATION OF INFORMATION FROM
STANDARD DATA, TIME STUDY AND ESTIMATION
• OVERALL TIME FOR THE JOB WILL BE WITHIN
ACCEPTABLE LIMITS
37. STRUCTURED ESTIMATION
• COMPARATIVE ESTIMATION
– RELIES ON IDENTIFICATION & MEASUREMENT OF
BENCHMARK JOBS OF KNOWN WORK CONTENT AGAINST
WHICH ALL OTHER JOBS TO BE MEASURED ARE COMPARED
– STEPS INVOLVED ARE
• BENCHMARK JOBS ARE SELECTED TO REPRESENT THE
WHOLE RANGE OF WORK INVOLVED AND TO
REPRESENT INTERMEDIATE POINTS ON THE OVERALL
SCALE OF THE JOB
• BENCHMARK POINTS ARE MEASURED WITH SOME
PRECISION USING AN ESTABLISHED WORK
MEASUREMENT TECHNIQUE
• IDENTIFY TIME BANDS OR SLOTS, DETERMINED BY
STATISTICAL ANALYSIS WHICH MAY NOT BE OF EQUAL
WIDTH, WITH EACH SLOT BEING ALLOCATED A BASIC OR
STANDARD TIME EQUIVALENT TO ITS MID POINT
38. STRUCTURED ESTIMATION
• EACH OF THE BENCHMARK JOBS IS ASSIGNED TO THE
APPROPRIATE SLOT
• WHEN ESTIMATING WORK SUBSEQUENTLY, THE
ESTIMATOR REFERS TO THE BENCHMARK JOBS AND
COMPARES THE JOB BEING MEASURED
• A COMPARISON OF THE WORK CONTENT OF THE JOB TO
BE ESTIMATED WITH A NUMBER OF THE BENCHMARK
JOBS
• ON BEING SATISFIED THAT THE CORRECT SLOT FOR
THE JOB HAS BEEN IDENTIFIED, THE SLOT BASIC TIME IS
ASSIGNED TO THAT JOB.
– BECAUSE OF THE HIGH SETUP COST OF THIS SYSTEM, THIS
TECHNIQUE IS MOST SUITABLE FOR SITUATIONS WHERE
THERE IS A LOT OF LONG CYCLE, NON-REPETITIVE WORK
e.g. MAINTENANCE WORK WHERE THE WORK IS SIMILAR
BUT NO TWO JOBS MAY BE IDENTICAL
39. METHOD STUDY
• DIAGRAMS
– STRING DIAGRAM
• STRING STRUNG TO FOLLOW PATH TAKEN BY MATERIAL
• DEALS TO SOLVE COMPLEX MOVEMENT & PLANT
LAYOUT
– CYCLE GRAPH
• INTRODUCED BY GILBERTH
• PHOTOGRAPHIC METHOD
• VERY ACCURATE
• USED FOR RECORDING VERY FAST MOVEMENT NOT
POSSIBLE FOR SEEING BY EYE
• LITTLE LIGHT ATTACHED TO THE FINGER OR HAND OF
OPERATOR TRACES THE PATH OF THE LIMB MOVEMENT
ON A PHOTOGRAPHIC PLATE AS A CONTINUOUS LINE
• DOES NOT INDICATE DIRECTION OR SPEED
40. METHOD STUDY
• 3. EXAMINE CRITICALLY
• EACH ACTIVITY CRITICALLY EXAMINED AFTER
RECORDING ALL RELEVANT INFORMATION
ABOUT THE SAME
– ALL ACTIVITIES FALL INTO TWO CATEGORIES
• VALUE ADDING ACTIVITIES: WHERE SOME WORK IS
BEING DONE ON THE MATERIAL
• NON VALUE ADDING ACTIVITY: WHERE NO WORK
IS BEING DONE ON THE MATERIAL
– EFFICIENCY CAN BE IMPROVED BY INCREASING THE
PROPORTION OF THE VALUE ADDING ACITIVITIES
BECAUSE THESE ARE THE PRODUCTIVE ACTIVITIES
41. METHOD STUDY
•
EXAMINE CRITICALLY contd…
– TWO SETS OF DETAILED QUESTIONS ARE ASKED
• PRIMARY
– TO INDICATE FACTS AND THE REASONS UNDERLYING
• SECONDARY
– TO INDICATE ALTERNATIVES AND MEANS OF
IMPROVEMENTS
– QUESTIONING PATTERN
• PURPOSE FOR WHICH, PLACE AT WHICH, SEQUENCE AT
WHICH, PERSON BY WHOM, AND MEANS BY WHICH, THE
ACTIVITIES ARE UNDERTAKEN
• WITH A VIEW TO ELIMINATE , COMBINE, REARRANGE OR
SIMPLIFY THOSE ACTIVITIES
– TYPICALLY
• PURPOSE: (P) WHAT IS DONE, (P) WHY IS IT DONE, (S) WHAT
ELSE CAN BE DONE, (S) WHAT SHOULD BE DONE
– BRAIN STORMING AND CREATIVE THINKING SESSION
42. METHOD STUDY
• PROCEDURE ….contd
• 4. DEVELOP AND EVALUATE THE BEST
METHOD
– RECORD METHOD PROPOSED
– CONSULT MANAGEMENT & WORKERS FOR THEIR
SUGGESTIONS
– WORKOUT COST OF INSTALLING NEW METHOD
– PREPARE NEW FLOW PROCESS CHART
– PUT UP REPORT FOR MANAGEMENT APPROVAL
43. TIME STUDY - STEPS
•
•
•
•
•
•
IDENTIFY JOB AND OPERATION TO BE TIMED
USE IMPROVED PROCEDURE
SELECT WORKER AND BRIEF HIM AND HIS SUPERIOR
ABOUT STUDY
COLLECT EQUIPMENTS, ARRANGE MACHINE, JIGS ,
FIXTURES ETC
BREAK JOB INTO OPERATIONS / ELEMENTS
DETERMINE NUMBER OF OBSERVATIONS TO BE TIMED
44. WORK SAMPLING
•
•
•
•
TECHNIQUE IN WHICH
– LARGE NUMBER OF OBSERVATIONS ARE MADE OVER A
PERIOD OF TIME OF ONE OR A GROUP OF MACHINES,
PROCESSES OR WORKERS
– RECORD WHAT IS HAPPENING AT THAT INSTANT
PERCENTAGE OF OBSERVATIONS RECORDED FOR A
PARTICULAR ACTIVITY OR DELAY IS A MEASURE OF THE
PERCENTAGE OF TIME DURING WHICH ACTIVITY OR DELAY
OCCURS
NORMAL FREQUENCY DISTRIBUTION AND CONFIDENCE LEVEL
ARE ASSOCIATED WITH WORK SAMPLING
A CONFIDENCE LEVEL OF 95.45% SIGNIFIES THAT THE WORK
STUDY ENGINEER IS SURE THAT 95.45% OF THE TIMES, THE
RANDOM OBSERVATIONS WILL REPRESENT THE TRUE FACTS
46. WORK SAMPLING….contd
• NUMBER OF OBSERVATIONS TO BE MADE
N = 4*p*(100 – p ) / L2 , WHERE
N = NUMBER OF OBSERVATIONS,
p = PERCENTAGE OF OCCURANCE,
L = LIMIT OF ACCURACY
47. PRE-DETERMINED MOTION TIME SYSTEM
(PMTS)….contd
• COMPONENTS OF A BASIC PMTS ARE
– REACH : MOVE HAND TO DESTINATION
– GRASP : SECURE CONTROL OF OBJECT WITH
FINGERS
– MOVE : MOVE OBJECTS
– POSITION: LINE UP & ENGAGE OBJECT
– RELEASE : LET GO OF THE OBJECT
– BODY MOTIONS : LEG / TRUNK MOVEMENT
• PMTS TABLES ARE AVAILABLE FOR STANDARD
TIMES FOR EACH TYPE OF MOTION UNDER
GIVEN CIRCUMSTANCES
48. PRE-DETERMINED MOTION TIME SYSTEM
(PMTS)….contd
• STEPS
– IDENTIFY BASIC MOTIONS CONSTITUTING OPERATION
– GET STANDARD TIME FROM PMTS TABLES FOR
IDENTIFIED MOTIONS
– ADD AND GET BASIC TIME
– ADD ALLOWANCES TO GET STANDARD TIME FOR THE
OPERATION
• RATING NEED NOT BE DONE AS TABLES
CONTAIN ALREADY RATED TIMES
49. PRE-DETERMINED MOTION TIME SYSTEM
(PMTS)….contd
• APPLICATION
– DIRECT OBSERVATION OF THE MOTIONS USED BY THE WORKER
– MENTAL VISUALISATION OF MOTIONS NEEDED FOR THE NEW
METHOD
– ANALYSIS OF A FILM / VIDEO TAKEN OF WORKER AT WORK
PLACE
• ADVANTAGES
– USE OF PMT STANDARD AVOIDS RATING WHICH LEADS TO
CONSISTENCY IN SETTING TIME STANDARDS
– ENABLES DETERMINING STANDARD TIME FOR A PROCESS
DURING DESIGN STAGE ITSELF FOR SUITABLE MODIFICATION
– COST ESTIMATES ARE ALSO POSSIBLE
– PMTS IS LESS TIME CONSUMING THAN OTHER METHODS
– USEFUL FOR SHORT CYCLES
50. PRE-DETERMINED MOTION TIME SYSTEM
(PMTS)….contd
• LIMITATIONS
– LOT OF PRACTICE REQUIRED TO APPLY CORRECTLY
– DEALS ONLY WITH NORMAL MANUAL MOTIONS OF AN
OPERATION
– DIFFICULT FOR ABNORMAL MOTIONS
– ALL CATEGORIES OF MOTIONS NOT CONSIDERED
WHILE COLLECTING PMTS DATA
51. ANALYTICAL ESTIMATES
• STEPS INVOLVED ARE:
– BREAK THE JOB INTO ELEMENTS
– USE STANDARD DATA TO GET TIME VALUES OF
ELEMENTS FOR WHICH SUCH INFORMATION IS
AVAILABLE
– MEASURE THE TIME VALUES OF ELEMENTS WHICH
ARE WORTH THE EFFORT
• TECHNIQUE IS A COMBINATION OF
INFORMATION FROM STANDARD DATA, TIME
STUDY AND ESTIMATION
• OVERALL TIME FOR THE JOB WILL BE WITHIN
ACCEPTABLE LIMITS
52. COMPARATIVE ESTIMATION
• RELIES ON IDENTIFICATION & MEASUREMENT
OF BENCHMARK JOBS OF KNOWN WORK
CONTENT AGAINST WHICH ALL OTHER JOBS TO
BE MEASURED ARE COMPARED
• BECAUSE OF THE HIGH SETUP COST OF THIS
SYSTEM, THIS TECHNIQUE IS MOST SUITABLE
FOR SITUATIONS WHERE THERE IS A LOT OF
LONG CYCLE, NON-REPETITIVE WORK e.g.
MAINTENANCE WORK WHERE THE WORK IS
SIMILAR BUT NO TWO JOBS MAY BE IDENTICAL