Unit 1 Work Study Additional Material

Basics of Work Study

Method Study & Work Measurement

Work Study

Systematic examination of the method of carrying out an activity so as to

Improve the existing method of doing the job, is called method study, and

To set up standards of performance , is called work measurement

With the objective of improving productivity

Deals with techniques of Method Study & Work Measurement, which are employed to ensure the best possible use of human, m/c & material resources in carrying out a specified activity

Work Study - Objectives

To recommend and implement 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.

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

Work Study - Objectives

BASIC WORK CONTENT

POOR DESIGN AND FREQUENT CHANGES

WASTE OF MATERIALS

POOR LAYOUT AND UTILISATION OF SPACE

INADEQUATE MATERIAL HANDLING

FREQUENT STOPPAGES AS PRODUCTION

CHANGES FROM ONE PRODUCT TO

ANOTHER

INEFFECTIVE METHOD OF WORK

POOR PLANNING OF INVENTORY

FREQUENT BREAKDOWNS OF MACHINES

AND EQUIPMENT

ABSENTEEISM AND LATENESS

POOR WORKMANSHIP

ACCIDENTS AND OCCUPATIONAL HAZARDS

TOTAL WORK CONTENT

WORK CONTENT ADDED

DUE TO POOR PRODUCT

DESIGN OR MATERIAL

SPECIFICATION

WORK CONTENT ADDED

DUE TO INEFFICIENT

METHODS OF

MANUFACTURE OR

OPERATION

WORK CONTENT ADDED

DUE TO HUMAN FACTORS

TO

TA

L W

OR

K C

ON

TE

NT

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,

STAFFING & A BASIS FOR

SOUND INCENTIVES

Higher Productivity/efficient human effort/evaluation of human work

WORK STUDY

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

Work study- advantages

Always looked upon by the supervisor &

workers or unions with suspicion

Sudden change is not appreciated

Work Study - Limitations

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

Work Measurement

Application of different techniques to measureand establish time required to complete thejob by a qualified worker at a defined level ofperformance

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

Qualified worker is one who has necessary physical attributes, and possesses reqd intelligence & education & has acquired skills to carry out the work in hand to a satisfactory standard of safety, quality and quantity.

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 )

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


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


Method Study - Techniques

Various Recording techniques used are

Charts

Outline process charts

Flow process charts: man, material, equipment types

Two handed process charts

Multiple activity chart

Travel chart

OPERATION

STORAGE

DELAY OR TEMPORARY

STORAGE

TRANSPORT

INSPECTION

OPERATION CUM

TRANSPORT

OPERATION CUM

INSPECTION

A chart / diagram giving an overall view of the process :

activities represented by symbols

PROCESS CHARTS

Diagrams

Flow

String

Cyclegraph

Chronocycle graph

String diagram

String strung to follow path taken by material

Deals to solve complex movement & plant layout

Method Study Recording

techniques

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)

Method Study Recording

techniques

SIMO chart

Used for micro motion studies

Time in terms of winks

Very accurate for detailed analysis

1 wink 1/2000 of a minute

Method study Recording

techniques

Work Measurement - Objectives

Target time for each job can be estimatedscientifically

Sound comparison of alternative methods can bemade by comparing their basic times

Useful incentive schemes can be generated bylinking these target times

Variance between actual time and the target time canlead to apply better control on the operations

It can lead to proper balancing of the work distribution

Forecast for future manpower and related costs canbe made

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

Work Measurement - Steps

Calculate Normal (Basic) time by usingPerformance Rating Factor

Add process allowance, rest and personalallowance and special allowances to Normal(Basic) time to obtain Standard time

Define the new method

Install the new method as agreed standardprocedure with the standard time allowed

Maintain the new standard practice

Work Measurement - Steps

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

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 or Normal (time) = Observed time *

Observed rating of operator / Standard rating ( i.e.

100 )


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


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


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


Standards

OBSERVED TIME

BASIC TIME

STANDARD TIME

RATING FACTORRELAXATION ALLOWANCE

DELAY ALLOWANCEINTERFERENCE ALLOWANCE

POLICY ALLOWANCE

BONUS

Performance Rating

ALLOWANCES

TIME ISSUED FOR PAYMENT PURPOSES

Work Measurement - Techniques

Time study Stop watch procedure

Work sampling

Pre-determined Motion Time Systems (PMTS) orElemental Motion Time Systems ( EMTS ) orBasic Motion Time Systems (BMTS ) ( work factorand M-T-M systems )

Structured estimation Analytical estimation

Comparative estimations

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

TECHNIQUE IN WHICH

LARGE NUMBER OF OBSERVATIONS AREMADE OVER A PERIOD OF TIME OF ONE OR AGROUP OF MACHINES, PROCESSES ORWORKERS

RECORD WHAT IS HAPPENING AT THATINSTANT

PERCENTAGE OF OBSERVATIONS RECORDEDFOR A PARTICULAR ACTIVITY OR DELAY IS AMEASURE OF THE PERCENTAGE OF TIMEDURING WHICH ACTIVITY OR DELAY OCCURS

WORK SAMPLING

PRE-DETERMINED MOTION TIME SYSTEM

(PMTS)

PRE-DETERMINED TIME STANDARD IS A WORKMEASUREMENT TECHNIQUE WHEREBY TIMESESTABLISHED FOR BASIC HUMAN MOTIONS (CLASSIFIED AS PER THE NATURE OF THE MOTIONSAND CONDITIONS UNDER WHICH THESE ARE MADE) ARE USED TO BUILD UP THE TIME FOR THE JOB ATA DEFINED LEVEL OF PERFORMANCE ( B.S. 3138:1969 )

MACROMOTION TIME MEASURED IN SEVERALSECONDS

MICRO MOTION ELEMENTS OF THE JOB ARE BASICHUMAN MOTION WITH DURATION OF 0.1 SECONDSAND LESS

OPERATIONS ARE RECORDED ON A MOVIE FILM

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

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

STRUCTURED ESTIMATION COMPARATIVE ESTIMATION

RELIES ON IDENTIFICATION & MEASUREMENT OFBENCHMARK JOBS OF KNOWN WORK CONTENTAGAINST WHICH ALL OTHER JOBS TO BE MEASUREDARE COMPARED

STEPS INVOLVED ARE

BENCHMARK JOBS ARE SELECTED TO REPRESENTTHE WHOLE RANGE OF WORK INVOLVED AND TOREPRESENT INTERMEDIATE POINTS ON THEOVERALL SCALE OF THE JOB

BENCHMARK POINTS ARE MEASURED WITH SOMEPRECISION USING AN ESTABLISHED WORKMEASUREMENT TECHNIQUE

IDENTIFY TIME BANDS OR SLOTS, DETERMINED BYSTATISTICAL ANALYSIS WHICH MAY NOT BE OFEQUAL WIDTH, WITH EACH SLOT BEINGALLOCATED A BASIC OR STANDARD TIMEEQUIVALENT TO ITS MID POINT

STRUCTURED ESTIMATION

EACH OF THE BENCHMARK JOBS IS ASSIGNED TOTHE APPROPRIATE SLOT

WHEN ESTIMATING WORK SUBSEQUENTLY, THEESTIMATOR REFERS TO THE BENCHMARK JOBSAND COMPARES THE JOB BEING MEASURED

A COMPARISON OF THE WORK CONTENT OF THEJOB TO BE ESTIMATED WITH A NUMBER OF THEBENCHMARK JOBS

ON BEING SATISFIED THAT THE CORRECT SLOTFOR THE JOB HAS BEEN IDENTIFIED, THE SLOTBASIC TIME IS ASSIGNED TO THAT JOB.

BECAUSE OF THE HIGH SETUP COST OF THISSYSTEM, THIS TECHNIQUE IS MOST SUITABLE FORSITUATIONS WHERE THERE IS A LOT OF LONGCYCLE, NON-REPETITIVE WORK e.g. MAINTENANCEWORK WHERE THE WORK IS SIMILAR BUT NO TWOJOBS MAY BE IDENTICAL

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

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

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

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

METHOD STUDY

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

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

BELL SHAPED CURVE

-1 +1

-2 +2 -3 +3

68.27

95.45

99.73

Standard Deviation Confidence Level %

1.00 68.27

1.96 95.00

2.00 95.45

3.00 99.73

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

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


(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


(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


(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


(PMTS).contd

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

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

Unit 1 Work Study Additional Material

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