Process Observation - ISEE 120

Work Measurement

• concerned with how long it should take to complete a job

  • First developed Purpose: increase productivity, define a standard for “full day’s work”, reduce costs

  • Examples: shoveling iron ore, determined the optimal load to be 21.5lb, Bethell steel used studies to reduce the workers needed at one plant from 400-140

  • Today’s Purpose: Incentive Plans, basis of lean / process improvement activities, and more. 
    

Standard Time

• amount of time it should take a qualified worker to complete a specific task, working at a sustainable rate, using given methods, tools, and equipment, raw materials inputs, and workplace arrangement. 

Time Studies

• watch novice, intermediate, and advanced and average to get the best result. 

Stopwatch Time Study

• develop a time standard based on observations of one worker taken over a number of cycles

• Redo time studies twice a year (if possible) & whenever a significant change hits.

Cycle

•  time it takes to do a task or procedure/process

Standard Elemental Time

• use of published data on standard times from across the industry

• use if you don’t have time to take your own data, will be less accurate

Work Sampling

• used to estimate the proportion of time that a worker or machine spends on various activities and idle time.

• records what the worker is actually doing at each part of the day

Industrial Engineer - Production Standard Uses

• productivity measurement,

• cost reduction,

• improvement methods,

• plant layout,

• equipment justification,

• incentive plans (how to incentivize productivity) 

Production Control - Production Standard Uses

• capacity planning,

• people planning,

• schedule production

Purchasing - Production Standard Uses

• lead times,

• subcontracting

Industrial Relations / Human Resources - Production Standard Uses

• fair day’s work hiring needs

• (sometimes used to evaluate performance of workers, ex: grades in school),

• grievance resolution

Marketing - Production Standard Uses

• setting prices (product cost),

• cost vs. price

Accounting - Production Standard Uses

• budgeting,

• payroll analysis,

• cost management

1st Step - Stopwatch Time Study Steps

• Go to gemba (shop floor) and talk with the worker who will be studied

2nd Step - Stopwatch Time Study Steps

• Observe the process for understanding FIRST (and read the Standard Operating Procedures SOP) if significant variability is observed cycle to cycle address that first. 

3rd Step - Stopwatch Time Study Steps

• Record the process steps. Divide work into steps based on natural breaks in motions and times

4th Step - Stopwatch Time Study Steps

• Determine the number of cycles to be observed.

5th Step - Stopwatch Time Study Steps

• Start the watch, record the cumulative times in the bottom box in each row - i.e. run the watch continuously. 

6th Step - Stopwatch Time Study Steps

• Calculate the incremental times for each step

7th Step - Stopwatch Time Study Steps

• Determine and record the average time for each step

8th Step - Stopwatch Time Study Steps

• Calculate total process cycle time

9th Step - Stopwatch Time Study Steps

• Add in support elements - handling, maintenance, recording info.

10th Step - Stopwatch Time Study Steps

• Record observations -problems, improvement opportunities (waste) - extra walking, repairs extra handling, etc. 

Time Observation form

• standard document to track a process, it’s cycle times and the number of cycles observed

Involve Employees in Creation Standards

• Make sample representative of population

• Select variety of experience, may need to talk to supervisor to find average or typical worker

• Vary times and days of studies; so that different conditions can be observed

Number of Cycles to Observe

• A function of variability of observed times, desired level of accuracy and desired level of confidence for estimated job time

• Refer to Chart: the faster it is the more cycles you should do. Best practice is around 20-30 (1-2minutes/cycle)

Element

• complete actions to which there is a clear trigger (beginning) and end

• Define clear physical set points that trigger each element or end each element

  • Easily recognizable

  • Logical in context 

Irregular Observations

•  irregular elements that do not occur every cycle, record time and frequency

  • Parts handling

  • Very minor repairs or adjustments

  • Inspection of samples

  • Changeover tasks

Avoidable delays

• Avoidable delays - shouldn’t be included in standard

  • Drinking coffee

  • Chatting with coworker

Unavoidable Delays

• should be included in standard

  • Reporting to supervisor

  • Breaking a tool

Pay Attention to

• Problems encountered that cause process time variability

• Experience level of the person doing the work

• Opportunity to for improvement

  • One hand vs. two

  • Parts presentation, handling

  • Layout of the workplace

  • Task sequence

  • Inventory - too much to little, wrong location

  • tooling , mechanical assist

Pace Rating

• observer estimates pace, ensure that standard is based on method not the operator

  • This aspect of a time study sometimes comes into play

Learning Curve Theory

• Time required to perform a manual task decreases with increasing repetitions

  • Degree of improvement is a function of the task being done

    • Short routine tasks will show modest improvement relatively quickly

    • Longer routines show improvement at a longer interval

    • T_n=T₁ x n^b . 

      • Is a inverse function

Personal Allowance

5% - bathroom breaks, drink breaks, lunch nut included, (generally always included)

Basic Fatigue

5% - (generally always included)