1. Summer Training Industrial Engineering Department
Time Study
Summer Training
Industrial Engineering Department

2. Work Measurement Tools
Time Study
Work Sampling
Standard Data
Predetermined Time Systems
Physiological Measures
Historical data provides a rough estimate of past production, IE’s are more concerned with a more scientific measurement process.
From the early days of Taylor and the Gilbreths to today, IE’s have been developing and refining the procedures used to measure work.
Purpose of the tools:
Develop Production Schedules
Determine wage payment plans
Estimate manufacturing costs
Baseline for estimating production increases
Identify employee training needs
Appraise employee performance
Justify additional production capapcity

3. Time Study Establishment of Time Standards Estimates
Historical records
Standards
Time study is the oldest type of work measurement performed. Technology advances have refined traditional devices, but the procedures remain the same.

4. Estimates Original method
Increasing competition requires fact rather than judgment
Unfair due to variability among estimators
Looking at a job and judging the amount of the time needed

5. Historical Records
Based on the record of similar, previously performed jobs
Measures time over entire job with no consideration of delays
Better than estimates (or lack of a standard)

6. Time Study Establishes a standard for a given task
Measures work content, allows for fatigue, personal and unavoidable delays
Increases the efficiency of the equipment and personnel
If standards are accurately established, they can increase the efficiency of the equipment and personnel. Poorly established standards result in high costs, labor dissension, possibly failure of an enterprise.

7. “A Fair Days Work”
The amount of work that can be produced by a qualified employee when working at a normal pace and effectively utilizing their time where work is not restricted by process limitations
Do you see any problems? What is meant by these terms?
Broad terminology, flexible
Basically saying employee should give a full day’s work for the time he or she gets paid w/reasonable allowances for personal, unavoidable delays & fatigue. Pace is representative of all-day performance by experienced, cooperative employee.

8. Responsibility Notification
Proper cutting tools, lubricants, materials, feeds & speeds, knowledge of procedure
Normal pace, no introduction of new movements
Union support
Communication from Analyst to Supervisor to worker to union steward to ensure everyone is on the same page and knows what is going on. EXAMPLES FROM ScriptPro, EMS

9. Equipment Stopwatch Decimal minute watch – 100 divisions (.01 minute)
Provides continuous or snapback timing
Electronic watch – accuracy of .001 second (600 times more accurate)
Provides both continuous and snapback timing
Computer Assisted Electronic Stopwatch
Figure 9.1 on page 378 shows a decimal minute watch.
Mechanical watch about $150, electronic about $50 and the price is dropping. Therefore, mechanical watches are quickly disappearing.

10. Equipment (con’t) Video cameras Time study board Time study forms (TP)
Time study Software
Training equipment
Video Cameras – record operators’ methods and time; also use to train new analysts
Board – to hold form and stopwatch
Forms – method, tools utilized, admin information
Software – Datawriter (captures electronically, download to PC), Programs for PC’s and PDA’s
These eliminate much of the drudgery of data entry and improves accuracy.

11. Figure 9.4 – Snapback Method

12. Time Study Elements Watch operator for several cycles
Break task down into fine elements
Look for natural breakpoints using both sight and sound
Record elements in proper sequence
Do not repeat identical elements descriptions, just reference the previous #
0.04 min is the limit for an element… if preceding and succeeding are long.
Example: finished piece hitting a container

13. Timing Record only what is necessary to rebuild later (TP) Two Methods
Snapback: Watch is reset after each breakpoint of an element
Continuous: Watch is allowed to run for the entire job being evaluated

14. Snapback Method
No clerical time needed to subtract from the previous observations as in continuous (TP)
Read and record Observed Time (OT) directly
Short element times are difficult to time
Possible cycle time lost during the snapback (N/A to electronic watch)

15. Continuous Method
Presents a complete record for the entire observation period
All delays and foreign elements are recorded
Better adapted to record short element times
Clerical work required

16. This table shows how to record data for a continuous study
This table shows how to record data for a continuous study. The clerical work comes in subtracting to determine element times.

17. Figure 9-7
Continuous Study

18. Missed Breakpoints Immediately mark an “M” in the W column
If operator omits an element, draw a dash (-) through the applicable space in the W column

19. Foreign Elements
Things that are external to the process that delay the work moving forward
Include: Supervisor interruptions, power losses, defective parts, leaving workstation, tool breakage, etc…
Occurring during an element, write A, B, C, etc…In the NT block (TP)
Both avoidable delays and unavoidable delays. Examples include: …
Foreign Elements enter time into W1 and W2 block.
<= 0.06 min, include in the element and circle reading.

23. Number of Cycles to Record
Tabulated data (TP)
Statistical methods
Confidence
Accuracy
Confidence – probability an interval about a sample statistic actually includes the population parameter.
Accuracy – Closeness of agreement between an observed value and accepted reference value
2 ways to determine number of cycles: specify confidence and accuracy ahead of time OR collect data, choose confidence or accuracy and calculate the other.
Z test versus t test (sample < 30)
Work Example.

25. Ratings Normalize the readings to the “average operator”
Can be for the entire element or individual cycles
NT=OT x R/100

26. Allowances Typically about 15% Personal interruptions Fatigue
Unavoidable delay
Standard Time (ST) = NT (1 + allowance)

27. Study Calculations
Start time, Finish time, Elapsed time, Time elapsed before study (TEBS), Time elapsed after study (TEAS), Total check time, Effective time, Ineffective time, Unaccounted time, Recording error (should not exceed ~ 2%)

29. Questions & Comments