Terms in this set (59)
List the eight steps in applying methods engineering
The eight steps of methods engineering are:
1) select the project
2) get and present the data
3) analyze the data
4) develop the ideal method
5) present and install the method
6) develop a job analysis
7) establish time standards
8) follow up the method
Explain Frederick W. Taylor's principles of scientific management
The principles of scientific management included: time study, standardization of all tools and tasks, use of a planning department, use of slide rules and other time saving implements, instruction cards
for workers, bonuses for successful performance, differential rates, mnemonic systems classifying products, routing systems and modern costs systems.
What is meant by motion study, and who are the founders of the motion study technique?
Motion study is the study of body motions used in performing an operation, with the thought of improving the operation by eliminating unnecessary motions and simplifying necessary motions, and
then establishing the most favorable motion sequence. Frank and Lilian Gilbreth are considered the founders of motion study.
How are time study and methods engineering related?
Time study should not be undertaken until a good method has been developed and installed.
How does the flow process chart differ from the operation process chart?
The flow chart contains more detail than the operation process chart. In addition to operations and inspections, it includes transportations, storages, delays, and the times and distance involved.
What symbols are used in constructing the flow process chart?
small circle = an operation
square = an inspection
triangle standing on its vertex = a storage
D = a delay
arrow = a transportation.
Why is it necessary to construct process charts from direct observation as opposed to information obtained from the foreman?
Information from the supervisor frequently is not accurate and may be biased. More reliable information is obtained by personal observation and measurement.
When would you advocate using the flow diagram?
Flow diagrams are useful in solving plant layout problems.
Reducing which of the three times - worker, machine, or loading - would give the greatest effect on increasing productivity? Why?
Reducing loading time would have greatest effect on productivity, because it decreases time in both worker and machine columns. That is the whole purpose behind SMED (single minute exchange of die) in the Toyota Production System.
How is operation analysis related to methods engineering?
Operation analysis is one technique (by examining nine different aspects of the operation) for accomplishing the goals of methods engineering.
Compare and contrast operations analysis with the lean manufacturing approach.
Lean manufacturing originated with the Toyota Motor Corporation as a means of eliminating waste which were classified into seven types (see Question 5). These overlap with traditional methods
engineering in which:
1) delays and transport elements are reduced using flow process charts analyses
2) excess motions are eliminated by using the principles of work design and motion economy
3) overproduction and excess inventory require additional storage and material handling , which is a waste to be reduced
4) defective products are an obvious waste producing scrap or requiring rework and also need to be reduced.
What are the seven mudas?
The seven types of muda or waste are:
2) waiting for the next step
3) unnecessary transportation
4) inappropriate processing
5) excess inventory
6) unnecessary motion
7) defective products.
What are the two general types of plant layout? Explain each in detail.
In product or straight-line layouts, the equipment and workstations are located so that the flow from one operation to the next is minimized for any product class. In process or functional layouts, similar
facilities or workstations are grouped together.
Explain why workstation designers should endeavor to have operators perform work elements without having to lift their elbows.
Raising the elbow requires static contraction of muscles, which is very fatiguing.
Define and give examples of the 17 fundamental motions, or therbligs.
Therbligs are basic motions of work
Effective Therbligs - directly advance progress of work. May be shortened but difficult to eliminate completely
1) Reach; RE
2) Move; M
3) Grasp; G
4) Release; RL
5) Preposition; PP
6) Use; U
7) Assemble; A
8) Disassemble; DA
Ineffective Therbligs - do not advance progress or work. Should be eliminated if possible
9) Search; S
10) Select; SE
11) Position; P
12) Inspect; I
13) Plan; PL
14) Unavoidable Delay; ED
15) Avoidable Delay; AD
16) Rest to Overcome Fatigue; R
17) Hold; H
How may the basic motion 'search' be eliminated from the work cycle?
Provide fixed locations for all tools and work components used by the operator at the work station.
What basic motion generally precedes 'reach'?
'Reach' is typically preceded by a 'release'.
Explain the difference between avoidable and unavoidable delays.
An avoidable delay takes place only when the operator is solely responsible, while an unavoidable delay is an interruption beyond the control of an operator.
Which of the 17 therbligs are classed as effective, and usually cannot be removed from the work cycle?
Reach, move, grasp, release, preposition, use, assemble and disassemble are classed as effective.
In a motion study, why is it inadvisable to analyze both hands simultaneously?
Analyzing both hands simultaneously would be much too confusing.
Compare and contrast a decision table with value engineering.
Although both techniques assist one in making a proper decision, a decision table is primarily a non-quantitative checklist, while value engineering provide weights and rankings to allow a more specific numerical value.
What is a job evaluation?
A job evaluation is a procedure for making an appraisal of a job and recording the details of the work so that it can be evaluate fairly.
What is the weakness of using historical records as a means of establishing standards of performance?
Historical records usually are not accurate enough to be used as input data for important decision making. Too often they allow more time than is required since delay time is frequently charged to a
particular order or item that really was not related to that order.
Explain why a range of rates rather than just one rate should be established for every labor
A range of rates allows for promotion within a labor grade.
How is a fair day's pay determined?
A fair day's pay is determined through the application of sound job evaluations.
What are the effects of poor time standards?
Poor standards mean that some are too 'tight' and other are too 'loose'. Those operators with tight standards will complain and cause problems. Operators with loose standards will not be working at
the true standard and the company will loose money.
What equipment is needed by the time study analyst?
Minimum equipment includes a good stopwatch, a time study board, time study forms, and a pocket calculator. A nice alternative approach is to use a hand-held PC or PDA with time study software.
Differentiate between constant and variable elements. Why should they be kept separate when dividing the job into elements?
Constant elements are those for which the time will deviate very little, while variable elements are those for which the time will vary within a specified range of work. Constant elements should be kept separate from variable elements so that they can be used as a source of standard data or formula construction.
What advantages does the continuous method of watch recording offer over the snapback method?
The continuous method provides a complete record of the entire observation period. It is better adapted to measuring and recording very short elements. In mechanical watches, no time is lost in
snapping the hand back to zero.
Explain what a foreign element is and how foreign elements are handled under the continuous method.
A foreign element is one introduced by the operator during the study that was not planned at the time the elements of the study were established. When a foreign element occurs, the observer will signify
the event by an alphabetical designation in the NT column. A short description of the foreign element is made in a separate space.
What factors enter into the determination of the number of cycles to observe?
1) the type of activity of the job
2) the cycle time of the job
3) the variation in cycle times
4) the desired confidence in or accuracy of study
Define a qualified operator.
A qualified operator is one who can achieve the established standard of performance when following the prescribed method at an average pace.
For what reasons are allowances applied to the normal time?
Allowances are used to care of personal and unavoidable delays and fatigue, so that a fair standard is developed that can be achieved by the qualified operator when exerting average effort.
Define the term standard time.
Standard time is the time required for an average operator, fully qualified and trained, and working at standard pace, to perform the operation.
When during a time study should a rating be given? Why is this important?
The rating is given while observing the element before the watch reading is taken. Only at the workstation can the analyst provide the best judgement of the skill and effort demonstrated.
Would there be any objection to studying an operator who was performing at an excessive pace? Why or why not?
It is preferable to study an operator who is working at a more standard pace. It is difficult to accurately evaluate performances at either end of the rating scale. A slow worker will produce loose times. A fast worker will produce tight times (regression toward the mean.)
What are the two methods used in developing allowance standard data? Briefly explain the
application of each technique.
The two methods are work sampling and the production study. Work sampling is the primary tool to establish allowances for various work categories. The production study is used in cases were grievances have been submitted and a careful scrutiny of all times and delays must be made.
What are some of the major factors that affect fatigue?
Illumination, noise, temperature, humidity, ventilation, weight of loads, posture, monotony of the task, repetitiveness of the task, mental strain of the task, etc. all affect fatigue.
Which operator interruptions would be covered by the unavoidable delays allowance?
Unavoidable delays cover interruptions from the supervisor, dispatcher, time study analyst, material irregularities, interference delays, etc.
What is meant by 'standard data'?
Standard data are elemental time standards that have been either taken from stopwatch time studies or
developed from predetermined time systems.
What advantages are there to establishing time standards by using standard data rather than by taking individual studies?
-The standards will be more consistent
-They can be established more rapidly
-A less experienced person can be used to establish standards
What is the danger of using too few studies in the derivation of a formula?
Insufficient data points can lead to significant inaccuracies in the plotting of curves and the resulting
algebraic expressions (i.e. large variance for the formula).
Who was originally responsible for thinking in terms of developing standards for basic work
divisions? What was his contribution?
F. W. Taylor with his developments of scientific management, stopwatch time studies and tool-life equation was responsible initiating the concepts of basic work elements.
What are the advantages of using predetermined times?
When properly applied by competent analysts, they establish consistent standards. They maintain a uniform concept of normal in connection with the predetermined time system used.
How is MTM related to the analysis of method?
To apply MTM (or any other predetermined time system), one must first make a detailed analysis of the method; hence, the use of the MTM-2 Analysis Checklist.
What are the three basic motion sequences used in BasicMOST?
The three basic motions are:
1) general move
2) controlled move
3) tool/equipment use.
What are advantages of work sampling over stopwatch time study?
-continuous observations not required
-less clerical time
-fewer analyst hours expended
-operator not subjected to long observation periods
-crew operations easily studied by one analyst
What are the pros and cons for using work sampling to establish standards of performance?
-eliminates the use if a stop watch
-is quite efficient
-allows several standards to be established simultaneously
-establishes standards on work that is difficult to measure
-standards are likely to be loose because of the bias in collecting data
-difficult to rate performance reliably
-since data collection may last over several weeks, standards cannot be established quickly
Compare and contrast the different ways of determining a standard time.
Standard times can be estimated from performance records and can be calculated with stopwatch time
studies, standard data, time formulas, work sampling studies and predetermined time systems.
Detailed comparisons are found in Table 16-2.
How can valid time standards help develop an ideal plant layout?
By knowing the exact requirements for facilities in terms of numbers, style, and load, the best possible utilization of space can be determined.
Explain the relationship between time standards and plant capacity.
With time standards, it is a matter of simple arithmetic to determine the capacity of a machine, a department, or entire plant. Department and plant capacity can be easily determined by calculating the capacity of bottle-neck operations only.
How do time standards allow the accurate determination of labor costs?
Labor costs are accurately determined by multiplying the reciprocal of the efficiency of the department by the average daywork rate. This would give the hourly direct labor cost based on standard production. Under incentive wage payment the standard multiplied by the base rate would provide the direct labor cost based upon standard production.
Explain the benefits of increasing production in relation to manufacturing cost.
By increasing production, fixed costs (such as general labor, insurance, basic utilities, etc.) decrease because they are spread over a larger output.
Differentiate between individual wage payment plans and group-type plans.
In individual plan's, each employee's compensation is governed by that employee's performance. Group plans are applicable to two or more workers who are working as a team that tend to be
dependent on one another.
What are the characteristics of piecework?
Under piecework operators are rewarded in direct proportion to output; the base rate is not guaranteed.
What are the fundamental prerequisites of a successful wage incentive plan?
1. policy providing for valid work measurement
2. adequate volume of work must be available for each operator (i.e. good scheduling and inventory control)
3. fair base rates
4. adequate tools
5. well maintained equipment
Why is it fundamental to keep time standards up-to-date if a wage incentive plan is to succeed?
Obsolete standards will result in wage payments that are not equitable. Loose time rates will provide take-home pay that is excessive, which will lead to the failure of the system and perhaps the business.
What does unduly high performance indicate?
Unduly high performance indicates a creeping looseness in standards and/or the introduction of a methods change for which no standards revision has been made.
What are some of the reasons for the failure of wage incentive schemes?
Failure can be grouped into three main categories:
1) fundamental problems such as poor standards, complicated wage schemes, ceilings on earnings
2) poor human relations with regard to proper training and support
3) poor technical administration of maintaining standards under methods changes, quality issues, grievance problems, etc.