Friday, November 15, 2019

Machine Work Study - Productivity Improvement Based on Machine and Machine Work Redesign


Innovation in Industrial Engineering
Productivity promotes competitiveness.
IE promotes productivity.
Innovations in Industrial Engineering are needed to increase productivity and competitiveness.

Taylor's Industrial Engineering


Taylor's industrial engineering consists of reduction of cost of production or productivity improvement based on redesign of machines, cutting tools, machining parameters and operator work practices in using machines,  hand tools or only hands. This point was highlighted by Ralph Barnes in his book on Motion and Times Study (3r ed. and 5th ed.). Barnes gives credit to Gilbreth for developing motion study even though he states that Taylor also contributed to development of improving human effort.

In the industrial engineering literature the contribution of Taylor and the implications of those contributions were not captured adequately in Motion and Time Study and there is no other subject that focuses on work related to machines.  Industrial engineering discipline lost the insight of Taylor. Peter Drucker said, after Taylor, there is no further great insight in industrial engineering. As industrial engineering discipline ignored Taylor's ideas, Drucker thought may be even Taylor's insight is half insight. It is the failure of subsequent industrial engineering academicians and professionals not to recognize the shortcoming of the theory and practice promoted by them.

The situation can be corrected by developing machine based industrial engineering following Taylor's lead. As work study became a popular subject (even Barnes acknowledge the subject), machine work study can be the name given to machine based productivity improvement. It is actually machine based industrial engineering. It is redesign of machine, its tools and accessories and machining processes based on the data generated in the industrial practice.  Cost data is an important industrial data and industrial engineering specially emerged as a discipline through its focus on engineering redesign based on cost data to reduce cost of production.



Machine Work Study – Industrial Engineering Analysis of Machine in Production System - A Presentation 



Machine Work Study – Man Work Study – Taylor’s Conceptualization of Scientific Study of Man-Machine Systems is a presentation done by Dr. K.V.S.S. Narayana Rao, Professor,  (NITIE), in December 2015

Taylor (1911) “The Principles of Scientific Management”  - Scientific management in a machine shop. 

Taylor described the implementation of scientific management in a machine shop.

First Stage – Machine Related Improvements

The slide-rules developed for determining optimal speeds and feeds were used to determine the optimal speed and feed for every element of work done on this machine.

The Pulling power of the machine at its various speeds and feeds was determined.

The belt drive and pulleys of the machine were adjusted so that the machine can be run at the proper speed for each element.

The shape of tools was specified and the tools made of high-speed steel (already in use in the company) were properly dressed, treated, and ground.

After preparing the machine, tools and instruction cards in this way, the machinist was asked to work according to the new instruction card and all varieties of work were finished on the lathe and the times were recorded.
The gain in time was found to range from two and one-half times to nine times.


Handwork of Operators – Time and Motion Study

The change from rule-of-thumb management to scientific management involves, however, not only a study of machine effort, that is the proper speed for doing the work and a remodelling of the tools and the implements in the shop, but also study of human effort.

Hence elaborate analysis of the hand work was done.

Hand work depends upon the manual dexterity and speed of a workman, independent of the work done by the machine. On some machines, the time saved by scientific hand work was greater than that saved in machine-work.


Industrial Engineering Discipline - Neglected Machine Productivity Improvement

Industrial Engineering discipline has not developed a subject for analysis of machine related elements and over time the area got neglected. Facilities planning and Material Handling were included in IE programmes but they were also not integrated adequately with process improvement (productivity engineering) function adequately.

Early Authors on Scientific Management.

They recognized the machine work improvement.

Bertrand Thompson  (wrote between 1914 to 1920)

Scientific management was implemented -  first, by determining with the aid of experienced investigators the best materials, equipment, machine methods and man methods to use. In many machine shops, it was the practice to issue to the workman an instruction card containing directions as to feeds, speeds, tools, and times of machine elements and also the manual elements with their standard times in their proper sequence. The combination of machine work improvement and man work improvement resulted in substantial improvements in machine shop work

Malcolm Keir (1918)

Scientific management advocates development of science and a thorough investigation of the work involving analysis of materials, equipment, environment; motion study, fatigue study, time study; research into the laws of health, psychological experiment and community improvement.

Farquhar (1919)

Difference between improving impersonal means of production and human effort in production.


In his paper, he took up for description first, the mechanical phase - the more purely impersonal aspects - divorced so far as possible from the human factor.  He stated that the two were to a certain extent interactive, yet sufficiently distinct to warrant separate treatment.

H.B. Maynard (1927 & 1937)

H.B. Maynard, a popular industrial engineer of the next generation, was a coauthor of "Time and Motion Study and Formulas for Wage Incentives" Stewart McKinley Lowry, Harold Bright Maynard, Gustave James Stegemerten, McGraw-Hill Book Company, Incorporated, 1927. In that book "operation analysis" was described. It evaluated various aspects of the production system including the machine. Maynard and Stegemerten later   authored "Operation Analysis" in which they discussed each and every step of operation analysis in a separate chapter. This book should have been included in IE curriculums.

One Conclusion

There is a need for developing a subject of machine element analysis in IE curriculum based on the definition. "Industrial engineering is system efficiency engineering and human effort engineering"by Narayana Rao.



What are the question that can be asked and evaluated in machine work study? - Barnes


Based on the questions suggested Barnes:

1. What is the operation?
2. What is the purpose of the operation?
3. What is the transformation of the material required?
4. What is the equipment now used?
5. What are the alternative equipments?
6. What are the cutting tools now used?
7. What are alternative cutting tools?
8. What are the cutting parameters now used?
9. What are the alternative cutting parameters?
10. What should be the best specifications for machine and machine parameters for the minimum cost that does the required material transformation reliably and accurately?

Maynard provided a list in his book "Operation Analysis."



Questions on Machine, Equipment and  Tools - Maynard and Stegemerten

The tools  and equipment used to perform the operation needs to analysed logically. The following questions are the sort that will lead to suggested improvements:

1. Is the machine tool best suited to the performance of the operation of all machine tools available?

2. Would the purchase of a better machine be justified?

3. Can the work be held in the machine by other means to better advantage?

4. Should a vise be used?

5. Should a jig be used?

6. Should clamps be used?

7. Is the jig design good from a motion-economy standpoint?

8. Can the part be inserted and removed quickly from the jig?

9. Would quick-acting cam-actuated tightening mechanisms be desirable on vise, jig, or clamps?

10. Can ejectors for automatically removing part when vise or jig is opened be installed?

11. Is chuck of best type for the purpose?

12. Would special jaws be better?

13. Should a multiple fixture be provided?

14. Should duplicate holding means be provided so that one may be loaded while machine is making a cut on a part held in the other?

15. Are the cutters proper?

16. Should high-speed steel or cemented carbide cutting tool be used?

17. Are tools properly ground?

18. Is the necessary accuracy readily obtainable with tool and fixture equipment available?

19. Are all operators and machines provided with the same tools?

20. Can a special tool be made to improve the operation?

21. If accurate work is necessary, are proper gages or other measuring instruments provided?

22. Are gages or other measuring instruments checked for accuracy from time to time?

Because of the wide variety of tools available for different kinds of work, this list could be extended almost indefinitely with specific questions. Foundries, forge shops, processing industries, assembly plants, and so on all have different kinds of tools, and different questions might be asked in each case. The list given above, drawn up principally and by no means completely for machine work, will indicate the kind of searching, suggestive questions that should be asked. 

A special list might well be drawn up by each individual plant to cover the questions on the kind of machines, machine tools that are used in its own work.

Machine Work Study - Introduction - YouTube Video Presentation

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Machine Work Study:  Methods, Techniques and Tools - YouTube Video Presentation

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Updated on  16 November 2019,  4 July 2019, 27 June 2019, 

1 comment:

  1. Machine work study is an important activity in industrial engineering. The time taken for machining is to be minimized with the objective of reducing machine cost component of total cost of a part or full product.

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