Time Study

1
Time Study

• What is time study?
• Time study is a work measurement technique for
  recording the time of performing a certain
  specific job or its element carried out under
  specific condition and for analyzing the data so
  as to obtain the time necessary for an operator
  to carry out at a defined rate of performance.

2

• Time study is a method of direct observation. A
  trained observer watches the job and records data
  as the job is being performed over a number of
  cycles.
• Time study equipment
• the stop watch in general, two types of watch are
  used for time study.
• Fly back
• Continuous
• These watches may be used any of the following
  time scales
• Seconds
• Decimal minutes
• Decimal hours

3
Selecting the job

• The job in question is a new one, not previously
  carried out (new product, component, operation or
  set of activities)
• A change in material or method of working has
  been made and a new time standard is required.
• A complaint has been received from a worker or
  workers representative about the time standard
  for an operation.
• A particular operation appears to be a
  bottleneck holding up subsequent operations and
  possibly previous operations.

4

• Standard times are required before an incentive
  scheme is introduced.
• A piece of equipment appears to be idle for an
  excessive time or its output is low, and it
  therefore becomes necessary to investigate the
  method of its use.
• The job needs studying as a preliminary to
  marking a method study, or to compare the
  efficiency of two proposed methods.
• The cost of a particular job appears to be
  evidenced by a pareto type of analysis.

5

• Before starting the study, there are a number of
  points to be observed in relation to the approach
  to the worker and the job he is doing.
• 1. Make sure the job has been method studied.
  Especially where the standard time is to be used
  for incentive purposes.
• 2. in an organisation where time study has never
  been used before, supervision and worker
  representatives should be told the reasons for
  the study programme and given and insight into
  tie study procedure.
• 3. It is good policy to ask the supervisor or
  workers representatives to be studied. The worker
  should be a competent steady person with an
  average rate of workig.

6

• 4. the worker should be told the reasons for the
  study. Why he has been selected and asked to work
  at his normal pace explaining any problems that
  may arise during the time the study is taken.
• 5. workers should be allowed plenty of time to
  settle down to new methods.
• 6. when making the study the observer should take
  a position where he can see the whole of the job
  being performed. This is generally to the side of
  the operator, slightly to the rear and
  approximately 6 feet away. No attempt should be
  made to carry out timing from a concealed
  position, without the operators knowledge or with
  the watch in the pocket.

7

• 7. the observer should take a comfortable
  standing position for the duration of the study.
• Rating
• Rating is a technique used to assess the speed
  and effectiveness of an operator.
• Consider may take into account
• Speed of movement
• Effort
• Effectiveness
• etc.

8

• How accurate is rating?
• Rating is subjective and relies on the skill of
  the observer carrying out the rating exercise and
  the observers concept of the rate of working
  relative to a standard of 100.

9
Element

• An element is a distinct part of a specified job
  selected for convenient of observation.
  Measurement and analysis.
• Breaking down the job in to elements
• Elements should be easily identified, with
  definite beginnings and endings so that, once
  established. They can be repeatedly recognized.
  The point at which one element ends and another
  begins is called break point. Breakpoints must be
  decided by the work study officer when he divides
  the work cycle into elements.
• All breakpoints can be recognised by a sound or
  by a change of direction of a hand or arm.

10

• Elements should be as short as can be
  conveniently timed by a trained observer, but
  should not be less than 0.10 minutes and more
  than 0.50 minutes.
• Manual elements should be separated from machine
  elements for future use as synthetic data.
• Short elements should be next to long elements.

11
Reasons for breaking down the job into elements

• Variations in speed, pace and effort which an
  operator works can be more accurately recorded
  over short periods of time. There could be some
  parts of the work-cycle with the operator
  performs better than others.
• The more clear-cut the item of work which is
  timed, separately, the more readily can an
  appropriate fatigue allowance be arrived at for
  incorporation with the element.
• To ensure that productive work is separated form
  unproductive work.
• To enable a detailed job specification to be
  produced.

12
SMV

• SMV time that is allowed to perform the job
  satisfactory.
• SMV Basic time Allowances
• Standard Minute Value

SMV B.T Allowances
13
Basic Time

• The basic time for the operation is found by
  applying concept of rating to relate the observed
  to that of a standard place of working.
• Calculated as follows
• Basic time observed time observed rating
• 
  100
• (BT Observed time Observed Rating A
  constant)
• 100

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• Example..
• Rating 50 75 100 125
• Observed time 1.2 0.8 0.6 0.5
• Basic Time 1.250 0.875 0.6100 0.5125
• 100 100
  100 100
• 0.6 0.6 0.6 0.6

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Types of allowances

• 1. Relaxation Allowances
• Personal needs
• This allowance provides for the necessity to
  leave the workplace to attend to personal needs
  such as washing, going to the lavatory or
  fetching a drink
• Common figures are from 5 to 7 percent of basic
  time.
• Basic fatigue
• This allowance, always a constant is given to
  take account of the energy expended while
  carrying out work and to alleviate monotony.
• A common figure is 4 percent of basic time.

16

• Contingency allowances
• A contingency allowance is a small allowance of
  time which may be included in a standard time to
  meet legitimate and expected items of work or
  delays, the precise measurement of which is
  uneconomical because of their infrequent or
  irregular occurrence.

17
Machine delay allowances

• These are applied to the total basic times for
  those elements which are concerned with the
  operation of machinery.
• Common used as follows
• Single needle lockstitch 9
• Twin needle lockstitch 14
• Three thread overlock 7
• Four thread overlock 9
• Five thread overlock 11

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Types of allowance

• 1. relaxation allowance
• Personal needs (from 5 to 7 of basic time)
• Basic fatigue
• (4 of basic time)
• 2. Contingency Allowances
• (less than 5 percent)
• 3. Machine attention Allowances
• Single needle lockstitch 9 - 12
• Double needle lockstitch 14 - 17
• Three thread over lock - 7
• Four thread over lock - 9
• Five thread over lock -11

19
SMV calculation
Element description Obser rating Obser. time Basic Time Freq. Basic Time/Gmt
Get bundle and sort parts 95 0.32 0.304 1/30 0.010
Match pocket flap to lining 105 0.11 0.116 1/1 0.116
Sew round flap 100 0.48 0.480 1/1 0.480
Trim threads and turn out flap 58 0.35 0.298 1/1 0.298
Top stitch flap 90 0.56 0.504 1/1 0.504
Close bundle and place aside 110 0.23 0.253 1/30 0.008
Total 1.416
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• Total basic time/garment (brought forward) 1.416
• Add machine attention allowances 7
• 7 fo (0.480 0.504) 0.07 x 0.984
  0.069 0.069
• Basic time MAA (1.416 0.069) 1.485
• Add personal needs and relaxation allowances 14
• 14 of 1.485 0.14 x 1.485 0.208 0.028
• Standard minute Value (SMV)
• Basic time all allowances
• 1.485 0.208 1.693 (SMV)

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Question 1

• As a result of a time study exercise the
  following information is available
• (BSI. 100 rating used)
• Elements Observed Observed
• Rating
  Time(min)
• Obtain and sort bundle 90 0.11
• Position breast pocket 75 0.16
• Sew to attach pocket 105 1.02
• Cut threads and reposition 100 0.05
• Pickup and position pocket 80 0.15
• Sew to attach flap 110 0.88
• Cut threads and aside gmt. 95 0.09
• Close bundle and write ticket 85 0.17
• Additional Information
• An 8 allowance is to be applied to all sewing
  elements to compensate for machine attention.
• A 14 relaxation allowance is to be applied to
  all work.
• The average bundle size is 10 garments
• Calculate the standard minute Value (SMV) for one
  garment.
• How many garments would you expect to be produced
  in a 465 minute working day. (Briefly explain any
  assumptions you have made.)

22
Operators Performance rating

• Listed bellow are the twenty levels of
  performance used in the rating process. You will
  note that each definition has a corresponding
  percentage figure. It is this figure that is used
  in leveling.

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Production and Efficiency Calculations
24
Production Calculation

• Target 60
• (individual) SMV
• Line Target Actual Minutes
• Total M/C SMV
• Actual Minutes No. of M/C operators X working
  mints efficiency x present

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Efficiency and Performance Calculations

• Efficiency Earned Minutes x 100
• (of individual) Available minutes
• Earned minutes No. of produced pieces X SMV of
  that
  activity
• Available Minutes Working Minutes

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• Example 1
• An operator worked for 8 hours on an activity of
  having a SMV of 5. She produced 82 pieces of that
  activity. What was her efficiency?
• Efficiency 82 x 5 x 100 85.42
• 8 x 60

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• Example 2.
• An operator worked for 9 hours on activity of
  having SMV of 1.21 0.80. She produced 195 250
  of those activities respectively. What was her
  efficiency?
• Efficiency 195 x 1.21 250 x 0.80 x 100
• 9 x 60
• 80.66

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• Line Efficiency Total Earned Minutes x 100
• Total Available
  minutes
• Total Earned Minutes no of produced Gmts. x SMV
  of that Gmt.
• Total Available Minutes No of operators x
  working minutes.

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• Example 3.
• A unit of 24 operators produced 400 Gmts. SMV of
  Garments is 20 assume a working day has 480
  minutes what was the line efficiency?

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• Line efficiency 400 20 100
• 24 480
• 69.79

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• Performance Earned Minutes 100
• (of individual) Available Minutes off std
• 
  minutes

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• E.g. 4
• An operator worked for 8 hours on an activity of
  having a SMV of 5. She produced 82 pieces of that
  activity. She had 40 minutes of stoppage time due
  to machine breakdown power failure. What was
  her performance?
• Performance 82 5 100
• ( 8 60) 40
• 93.18

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Allowance and Calculation

• Personal Needs and Fatigue 7.5
• Other (Standing) 4.0

Machine Type Allowance
DNL SNL/BH DNC/50L SNC/30L BS/BT Other 17.5 12.5 9.0 7.5 5.0 2.0
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• Operation TGT/HR 60
• SMV of the operation
• Line Target
• TGT/Working Time No of operator working mints
• Total machine SMV
• Overall Efficiency Earned SAH 100
• Clock hours
• On std Efficiency Earned SAH 100
• Clock HRS Lost
  HRS

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Production Planning

• Load and capacity Planning
• Successful planning requires knowledge of two
  variables to determine the time required to
  manufacture a contract.
• Load How much work we are putting on a section
• Capacity How much work a section is capable of
  completing
• In an ideal situation
• gtgt Load Capacity

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Load and capacity

• LOAD Contract size x Work content
• Capacity The amount of work the factory or
  section is capable of doing.

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The scheduling rule

• Balance load and capacity
• Arrange the programme of work so that the load
  can be achieved
• Use common units standard minutes

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Balancing Capacity

• Load
• Uncertainty about the number of garments to be
  sold Demand?
• Speculation?
• Prediction?
• Uncertainty about work content
• Standard minute value
• Measured
• Estimated

• Capacity
• Uncertainty about the number of operators and
  performance
• Total numbers
• Attendance hours
• Absenteeism
• Performance
• Learning curve
• Uncertainty about the equipment
• Availability
• Reliability

39
The pre Production plan for the next 13 week
season has provided the following information.

• Style Order qty SMV per gmts Total SMVs
• Avon 10000 42
• Bar 8000 30
• Clyde 24000 20
• Dee 12000 65
• Calculate the average weekly load in standard
  minutes
• If the factory employs 80 operators, has 4
  absenteeism, works a 40 hour week, has an
  efficiency of 8 what is the weekly capacity in
  standard minutes?
• Is the factory sufficient capacity to meet the
  plan?

40
The Pre-production plan for the next 13 week
season has provided the following information

• Style Order qty SMV per Gmts. Total SMVs
• Avon 10000 42 420000
• Bar 8000 30 240000
• Clyde 24000 20 480000
• Dee 12000 65 780000
• Calculate the average weekly load in standard
  minutes 1920000sms/13 weeks 147692 SMs
• If the factory employs 80 operators, has
  4absenteeism, works a 40 hor week, has a
  eficiency of 85, what is the weekly capacity in
  SM? 80400.960.85156672sms
• His the Factory sufficient capacity to meet the
  plan?
• Yes