Prof. A.G. Anderson - 1928
Anderson, A.G. (1928), Industrial Engineering and Factory Management, Ronald Press, New York
Professor Anderson synthesized the developments in industrial engineering up to 1928 in a chapter in his book. Have industrial engineers ignored his work? Barnes followed Anderson in developing his book Industrial Engineering and Management in 1931. But the latter developed Motion and Time Study overshadowed the earlier development of Process Study - Operation Study. Barnes tried to explain his work methods design containing process analysis and operation analysis. But the direction went into undesired ways and industrial engineering suffered.
Barnes clearly pointed out that Taylor was the pioneer is task improvement and work methods design. But his major focus was on machines and machine work. The development of motion study, that is detailed study of the work of operators was done by Gilbreth. So Motion and Time Study was only partial description of work methods design. Barnes was clear on it. But industrial engineering professors made a mistake.
CHAPTER XX OPERATION STUDY-NATURE AND SCOPE
Productivity of engineering systems is the primary aim of industrial engineering. Along with productivity, some other performance dimensions like quality, comfort and health of operators, profitability of the firm, income of employees, market demand etc. become areas of attention for industrial engineers.
Production or manufacturing system is an engineering system.
Systems have components that interact and create outputs. La nd, buildings, equipment that includes production equipment, inspection equipment, material handling equipment, stores and storage facilities are parts of production system. Energy sources like power supply, steam generation facilities, compressed air supply, water supply etc. are required for functioning of the system. Operators run the machines. Material and parts supply is required and planning and communications are required. Suppliers provide materials and parts. Customers buy the output. Processes, technologies, operations, methods, motions of operators and control procedures have to be present in the system to produce parts, assemblies and instructions.
The aim of production system study is to make the manufacturing establishment in its entirety most productive; to insure that the personnel, buildings, equipment, operating and auxiliary departments are suitable for the work to be done, and function to advantage.
Operation study involves an analysis and standardization of all factors influencing the doing of a task, the development of the best method of performance, and the determination of the time required.
The following constructive results accrue from operation study:
(1) the best manufacturing conditions as to layout, equipment and surroundings are established and maintained, and improvements stimulated; (2) the best methods, and the skill of the most expert workers are made available to all, increasing average efficiency and earning power; (3) uniformly consistent and correct task times are set affording an accurate basis for setting wage rates fair to man and management; thus eliminating a prolific cause of industrial unrest; (4) production is increased; (5) quality is improved and made more uniform; (6) waste of time, materials and human energy is eliminated; (7) production may be scheduled and delivery dates set with assurance; (8) a detail check is provided on the effective functioning of every auxiliary department as previously arranged for; they become truly service departments of the highest order.
As a consequence manufacturing costs will be at a minimum, making higher wages and lower prices possible. Operation study is the foundation of good management.
Job Standardization
Job standardization is determining the best method for doing the task. The standardized job is to be taught to the workers.
Job Standardization.-
Job standardization denotes the establishment of the best possible conditions with respect to all physical factors which influence the job and is a first natural objective in all operation-study work. A new plant, laid out, designed, built and equipped completely ready for operation by progressive managers and experienced engineers will presumably be ideal with respect to job standardization. Where ideal conditions cannot be realized in existing workshops the best standards attainable can be set and maintained. An outline for job standardization is as follows:
OUTLINE FOR JOB STANDARDIZATION AND MOTION-STUDY WORK
A. Object
B. Location
C. Personnel
1. Number 2. Position of each operator 3. Method of wage payment
D. Equipment
1. Machines 2. Tools 3. Transportation facilities 4. Miscellaneous 5. Floor plan
E. Materials
F. Relations to other processes
1. Processes preceding 2. Processes following 3. Routing methods
G. Local conditions
1. Lighting 2. Ventilating 3. Heating 4. Safety devices 5. Sanitation 6. Fire protection
H. Process A complete and detailed account of every motion made, etc.
I. Lost motion and interference
J. Recommendations
Some of the important things to consider are as follows:
EQUIPMENT.
A study of existing equipment may suggest changes and improvements or repairs. The need to bend over, to lift heavy materials or parts, to take more than a step or two, slows up the work and tires the operator; which suggests the economical utilization of mechanical devices.
Processes should be those which combine economy with uniformity of standard quality.
Standard methods are to be developed after standardization of machines within each class, and the maintenance of normal conditions with respect to their upkeep.
Proper means of transporting and handling materials must be utilized.
TOOLS.
Assurance must be had that the tools needed for a given task will be available. This phase of the investigation will consider the tool room organization and administration, the selection of proper steels, shape, size, variety and tempering of tools, procedure in issuing them when needed, and their repair and re-sharpening after use. Likewise all necessary auxiliary equipment in the way of bolts, blocks, clamps, dies, jigs, etc., should be standardized, perhaps for each operation-kept in good condition, and made readily available.
MATERIALS.-Economy in the use of materials should be studied, considering comparative values of material and labor. The latter may be a relatively unimportant item. Waste should be considered, remembering that workmen constantly handling a material may become careless and insensible to its value. Disposing, reclaiming or utilization of waste should be provided for. Considering the consumer's use of the product and methods of manufacture, the kind and grade of material used should be analyzed. Another material may be better, a cheaper grade prove as suitable, or a better grade may be less expensive to process and the finished product more uniform as to quality. A study of storeroom practice may suggest ways of eliminating delays in the issuing of materials.
LAYOUT. All the machines and workplaces in the department have a relation one with another, and must be considered together. Departmental arrangement is important. A uniform, maximum flow. of materials in process is the aim. To achieve this, moves between operations should be short, space sufficient, inspection points and storage areas provided for, production facilities balanced so that congestion will not take place at certain points, with perhaps idle work areas at others. Tool, store and stock rooms must be readily accessible and service centers convenient. Most factories grow by adding manufacturing space here and there, until finally production arrangements are haphazard. In one instance the path of travel of a part was reduced from 535 feet to 27 feet, four truck trips including two elevator journeys dispensed with, and the method changed to require four operators instead of five. Much time was saved.
ENVIRONMENT.-Intelligent attention will be given to adequate illumination, ventilation, sanitation, comfort of floors, unnecessary noises or objectionable odors, and danger hazards. Environment makes its impress upon the worker and is reflected in his work; hence it should be good. Adjustments and changes suggested by the foregoing analysis may be few and unimportant, or they may be extensive and costly, requiring many months for completion. When the work is completed provision must be made for the maintenance of the standards established. Best performances are possible only when conditions are "right," and standard performances possible only when conditions do not vary materially. Operation study brings about a great change in the relation of auxiliary departments to the operating departments, and the attitude of executives. Ordinarily the job, as represented by the man doing it, has little option but to accept equipment, arrangements, tools, materials, environment, etc., as they come. The worker is at the bottom of the ladder of authority. With operation study job requirements are analyzed and standardized in every particular; and the service required of auxiliary departments and executives is outlined in minute detail, and effective functioning checked at every turn. The job is now supreme, and workmen in a position to demand effective management. This is as it should be, for mental inertia and laziness are as prevalent among one group as the other.
Time Study and Motion Study -Beginning of Process Studies
The Beginning of "Time Study."
In 1881, Frederick W. Taylor originated time study in the machine shop of the Midvale Steel Works at Philadelphia, with the object of determining proper standards for a day's work and increase productivity. His experience as a workman and a foreman made him realize output can increase perhaps two or three times, if the management could know the possible output from a machine-operartor combinator , and would then provide a sufficient incentive to the operator for its accomplishment. Taylor improved machines and determined proper speeds and feeds that gave higher outputs. In combination with improvement of machines and machine effort, he studied movements of operators and improved them. He got productivity improvements varying from two hundred percent to seven hundred percent in various parts and machines. Time study involves breaking down a task into elements, measuring the time presently taken for each element, searching for alternatives to reduce the time taken, and creating a modified task that takes less time. Taylor explained the steps in a time study in multiple papers.
Taylor's Outline and Definition of Time Study.
In 1912, Taylor had occasion to outline and define time study, and he said: "Time study" consists of two broad divisions, first, analytical work, and second, constructive work.
The analytical work of time study is as follows:
(a) Divide the work of a man performing any job into simple elementary movements.
(b) Pick out all useless movements and discard them.
(c) Study, one after another, just how each of several skilled workmen makes each elementary movement, and with the aid of a stop watch select the quickest and best method of making each elementary movement known in the trade.
(d) Describe, record and index each elementary movement, with its proper time, so that it can be quickly found.
(e) Study and record the percentage which must be added to the actual working time of a good workman to cover unavoidable delays, interruptions, and minor accidents, etc.
(f) Study and record the percentage which must be added to cover the newness of a good workman to a job, the first few times that he does it. (This percentage is quite large on jobs made up of a large number of different elements composing a long sequence infrequently repeated. This factor grows smaller, however, as the work consists of a smaller number of different elements in a sequence that is more frequently repeated.)
(g) Study and record the percentage of time that must. be allowed for rest, and the intervals at which the rest must be taken, in order to offset physical fatigue. The constructive work of time study is as follows:
(h) Add together into various groups such combinations of elementary movements as are frequently used in the same sequence in the trade, and record and index these groups so that they can be readily found.
(i) From these several records, it is comparatively easy to select the proper series of motions which should be used by a workman in making any particular article, and by summing the times of these movements, and adding proper percentage allowances, to find the proper time for doing almost any class of work.
(j) The analysis of a piece of work into its elements almost always reveals the fact that many of the conditions surrounding and accompanying the work are defective; for instance, that improper tools are used, that the machines used in connection with it need perfecting, that the sanitary conditions are bad, etc. And knowledge so obtained leads frequently to constructive work of a high order, to the standardization of tools and conditions, to the invention of superior methods and machines.*
Remarks.
It will be noted that under (j) job standardization work is suggested, while (b) and (c) refer to motion study, developed in detail by Frank Gilbreth. The outline suggests the compilation of data for an entire trade, as that of machinist, for example, which when suitably indexed would enable a man sitting at a desk to determine accurately the time of doing any operation in the trade. It has not been possible to do this because of the variety of equipment and tools used, differences in methods, and varying conditions existing in different plants.
Synthetic Time Studies.
Some tool manufacturers now provide fundamental operation time data with their machines which approximates what Taylor had in mind. This is supplemented in plants by studies designed to yield time data covering all elemental motions made in using the equipment. With sufficient data of this character, properly arranged and classified, the operation time for any job within the capacity of the machine may be calculated without the need for taking individual studies.
Operation Time Studies. In the past, most efforts have been devoted to making operation time studies-ascertaining the proper time for the doing of an individual task or operation. This is accomplished by observation of the worker at the machine, or work sta- tion while doing the job. The Use of Charts, Diagrams and Formulas.-Data obtained in either of the ways suggested may be utilized to prepare standards which are expressed in charts, diagrams or formulas. By the use of these, task operation times may be determined. Examples are given in Chapter XXII of the use of charts, diagrams and formulas.
Motion Study.-Motion study involves an analysis of the movements made in performing an operation with the object of eliminating useless and unnecessarily fatiguing motions and arranging the necessary ones in a logical sequence. It is an aid to job standardization work in suggesting proper facilities as crane service, standardized workplaces, or improved arrangements. Utilizing these proper facilities, the motions which the worker makes in performing the task are then subject to study. It is well to record the motions of each hand separately and the need for using both hands as is done thereon. The performance of the most successful workers should be studied to the end that the best method may be evolved for the benefit of all. Seldom will the practice of one worker be ideal in all respects. Effort is made to achieve a method which is simple, direct and easy to perform, and in which results are attained by straight, short and quick motions which succeed each other naturally, establishing a rhythm and harmony of action of the hands and body that makes for accuracy, speed and minimum fatigue.
Thoughtful observation of a worker and consideration of the significance of his movements, of the machinery, tools and accessory equipment used, of incidental delays, the receipt of materials, manner of its handling and of the disposal of his finished work, may well suggest action leading to increased productivity at less cost and with less effort. A machinist turning out 198 castings a day, each weighing 35 pounds, in carrying them to and from his machine walked over two miles a day under load. By rearranging his stock trucks he at once doubled his output and earning capacity. An extreme case perhaps, but innumerable instances of time savings ranging upward from a few per cent are being effected. Preliminary stop-watch studies may aid in judging the relative worth of alternate methods and reveal facts not apparent from observation.
Administration and Production Control.-
The productivity of a department or a work station will be influenced by the success with which work in process is controlled, and the smoothness with which the administrative machinery functions. Production centers must be coordinated, delays and interruptions anticipated and guarded against, and supply and auxiliary service departments made efficient. It should be appreciated that while motion study accompanied by the suggested job standardization work invariably results in increased output this is not accomplished by speeding up the worker, but by reducing friction, training in proper methods, and removing obstacles that he has previously needed to overcome. Poor lighting or deficient ventilation slows up the worker; while the need to manipulate a machine which can be made to operate automatically, or to lift and carry a 50 pound casting 10 or 15 feet every few minutes are obstacles to easy, rapid work. Observation of the worker accompanied as it is by a detailed study of the task provides data for selecting workers possessing the necessary physical and mental qualifications and manual or trade skill. This may be available to the personnel department in the form of a job specification card. (See Figures 78A and 78B.)
Micromotion Studies.-The Gilbreths have developed a highly scientific method of motion study for work which is intricate or complex and demands unusual precision. It consists in taking motion pictures of the worker which record the speed simultaneously with a two or three dimensional path of motions. In the field of view is placed a standard clock together with a special clock with a large dial and one hand which registers time in fractions of 1/2000 of a minute. Instruments recording air conditions may also be included and other data photographed as necessary to supply a complete record of all conditions surrounding the task. This record may be studied in the laboratory and the film run fast or slow as desired, or held stationary, permitting repeated analysis without the need for taking new studies. For refined work small electric lights are attached to the hands or body of the operator which flash at uniform intervals and indicate. the path of the motion and the time taken. The use of a stereoscopic camera brings out the third dimension in the motion path. When the method is chosen wire models may be constructed showing the path of motions and the workers trained accordingly. Similar models showing ordinary procedure serve to impress upon the worker the simplicity and advantage of the chosen way. Remarkable results have been achieved with micromotion studies in perfecting methods and reducing operation times.
Stop-Watch Study.
The primary purpose of stop-watch studies is to record operation times and provide a basis for setting rates. It is the third and final phase of operation study. With facilities for doing a task and the conditions surrounding it at their best and standardized, and with the worker trained in the best method of accomplishment, studies with a stop-watch enable an observer to determine the time it ought to take to perform the task. Rates set in this manner will be based upon facts and relatively fair as compared with each other. Other methods of determining task times are (1), comparison with past performance, (2) judgment of the foreman, (3) sending through trial lots, and (4) utilizing fundamental machine data supplied by equipment manufacturers together with the experience of shop executives. All these methods, however, have their defects. Past performances are not a fair guide. One job may be done by qualified men working with enthusiasm; another by mediocre mechanics or poor workmen without interest in their jobs. In any event, good men and poor ones will be employed. If rates are set on a basis of past performance the good men already doing a good day's work will enjoy but slight wage increases; while the poorer workmen by simply becoming proficient and endeavoring to do a fair day's work will profit greatly. The first group are penalized because of their skill and previous application; the second capitalize previous incompetency. Then again, the conditions under which jobs are done change, and the elements included under a job title vary. Lacking reliable records these changes may not be evaluated accurately or may even escape notice so that rates set on this basis are likely to be both unfair in themselves and inequitable as compared with other rates, and hence cause dissatisfaction.
The foreman's judgment will prove fallible in the same respects, as he cannot be expected to possess superior skill in all the work which he supervises, guesswork inevitably plays a part in his attempts at rate-setting. Favoritism may manifest itself. Conditions may not be right, methods may be wrong, and the worker may be endeavoring to influence the setting of a favorable time. Sending through trial lots provides information of the time which an operation does take, but not necessarily data as to the time it ought to take, for the reasons just noted. Utilizing machine tool data with experience of executives provides an approximation to time study, but is a compromise. It usually denotes a desire on the part of management to inaugurate operation study work, and suggests the possible opposition of the workers to its use. To an increasing extent management and men are favoring the use of time study as the one best method of setting task times. The improvement effected by standardization work and training in best methods that precede stop-watch studies are the phases of operation study that enable work to be accomplished in minimumi time. Stop-watch studies tell men and management what that time should be and eliminate cause for disagreements on this vital point.
Combination of Job Standardization, Motion Study and Time Study.
It is not to be inferred that job standardization, motion study, and time study are always three distinct phases of operation study, each completed in entirety for a department or plant before the succeeding step is begun. When operation study is inaugurated in an existing plant this procedure is to be recommended if times set are to prove equitable, for changes and improvements effected for the benefit of one operation will influence the time for doing others. In a new plant the first step and much of the second will have been cared for in its design. In going plants, however, with well-established operation-study departments the situation is somewhat different. Industry is not static and the evolution constantly taking place necessitates changes and readjustments. New methods are introduced, improved equipment is added, the product is altered in design, or possibly new items are added. Materials are constantly being replaced by others, newly developed and more suitable or cheaper to use. Recent years, for example, have seen the development of bakelite, decalcomania, drop forgings, aluminum and steel castings, pressed steel and punched parts. Likewise machine improvements offer possibilities for combining operations, and perfection of processes for simplification. For example, the introduction of a new method of finishing automobiles has cut down by several days the production time for this phase of the work, and greatly decreased the space and facilities needed. This typical situation calls for continual revision of obsolete task times and the setting of standards for new operations. In all such cases job standardization and motion-study work will be carried on as a preliminary to each and every stop-watch study of an individual task or operation. The work is never finished.
Questions for Review
1. What does operation study involve doing?
2. What is the aim of operation study?
3. What important benefits are expected to accrue from operation study?
4. Who originated operation study? When? Why?
5. Differentiate between synthetic time studies and operation time studies. When is each used?
6. Explain the meaning and nature of job standardization. Of motion study. Of stop-watch study.
7. How are job specification cards prepared, and what is their value?
8. Name and discuss methods other than stop-watch studies which can be used to determine task times.
9. When are the three steps in operation study combined in one task, all to be accomplished by the "observer"?
1 In laying out work in sequence each man has a certain standard time in which to do his job. The work may thus be handled progressively to succeeding operations and machines and men can be kept uniformly busy and the product completed in minimum time. 2 The popular term for the more inclusive title "Job Standardization, Motion and Time Study," or Operation Study." It is also used to indicate time studies made with a stop-watch. 346
4 From a paper contributed to the discussion of a committee report entitled, "The Present State of the Art of Industrial Management," American Society of Mechanical Engineers, 1912.
Training the Planning Staff, by Donald Ross, Manufacturing Industries, Vol. 9, No. 4, p. 375.
THE BLANK UNDERWEAR COMPANY Motion Study-Observation Sheet OPERATION-Collar Seaming OPERATOR-W. P. DEPARTMENT-Finishing OBSERVER-C. W. L. LEFT LAND DATE- TIME-9:00 to 11:00 A. M. NO. I PLANT GARMENT Reg. Light Weight Union Suit MACH.-Union Special BOTH HANDS RIGHT HAND No. 1. Turn bundle right side up.. 2. 3. 4. Pull out cord. 5. Hold ticket.. 6. Hold ticket.. 7. 8. Hold bag open.. 9. Hold bag open. . IO. II. 12. 13. 14. 15. Hold garment.. 16. Hold garment.. Lift bundle to lap with necks at left and straighten Untie cord Hold back garments Sign ticket Clip ticket Open bag Take out collar and lay on table at right Take out back pieces and lay on table at right Shirrup bag Lay bag on table at left: cord ready for bundle Pick up garment Open top part Place on machine left front corner ahead 17. first one only-hold end of collar. 18. Place collar on garment and hold.. Feed and guide to second 19. 20. Hold garment. 21. Bring collar even. 22. 23. Break thread. 24. Lift garment.. 25. Fold in the middle. 26. 27. Pick up ring end of cord. 28. Hold ring. 29. Hold bundle. 30. Hold ring and cord. 31. Pick up one back-piece Pick up one collar Fold other end over to test marks Hold garment mark, first mark at seam Put in back piece from under side Fold back piece Feed and guide to come out even Hold garment Take it by middle Lay on table over cord Pick up free end Put free end through ring Pull cord through ring Loop and tie 1 Lay bundle aside Figure 77. Simple Motion Study 6
From Management's Handbook, The Ronald Press Company, p. 806.
7 See Applied Motion Study, by Frank B. and L. M. Gilbreth.
О Job Name. Departments. Male JOB SPECIFICATIONS BORING MILL HAND-VERTICAL о DESIRABLE EMPLOYES' QUALIFICATIONS Female. ENGLISH Speak X Read Write SCHOOLING Quick Rough Public NATURE AND CONDITIONS OF WORK Floor X Standing Bench X Sitting Heavy or Fatigue X Medium X Machine Stooping Light Job No.. о B-27 High Technical University Hot Dust Dirty EEFEEDEE Kindred Occupation. Machine Tools Operated. Personal Hand Tools Required. Slow Monotonous Dangerous KIT OF MACHINIST'S TOOLS Close X Exacting Approximate time required to train an inexperienced employe to do this work Cold or Outside Wet or Moist Fumes Greasy Day work job Piece work job hour Day Work day Rate is from (a). week to hour Base is from day Rate to week Overtime Remarks. RATE DATA hour is from Starting rate day week to hour Approximate are from Piece work day earnings to week Bonus or Prémium (c) Figure 78A. Job Specification Card
Job Name BORING MILL HAND-VERTICAL Job No. B-27 THE DUTIES OF THIS JOB ARE: To set up and operate a Vertical Boring Mill on all classes of work. THE NECESSARY EMPLOYE QUALIFICATIONS TO FILL THIS JOB ARE: (1) Must be an experienced mechanic who is able to take care of and operate a Vertical Boring Mill on all classes of work, working to samples, drawings or instructions, interpreting mechanical requirements and figuring necessary dimensions. (2) Should be skilled in the use of modern tools and measuring instruments such as micrometers, calipers vernier calipers, gauges, protractors, dividers, surface gauges, etc. (3) Must be able to make layout, set up, placing, blocking, bolt- ing and clamping large or small, heavy or light springy parts and be capable of very accurate machining of same. (4) Must be capable of grinding `and setting the different tools used. (5) Must be thoroughly experienced in Vertical Boring Mill methods, such as facing, boring, undercutting, turning taper fits and working to close measurements. (6) Must have a working knowledge of the proper feeds and speeds to use in order to get the best results with different kinds of material. Remarks о Figure 78B. Reverse of Job Specification Card
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