Process Industrial Engineering - Methods and Techniques - Part 1 - Part 2 - Part 3 - Part 4 - Part 5
Lesson 74 of Industrial Engineering ONLINE Course.
Case 74 of Industrial Engineering ONLINE Course.
Process Industrial Engineering Methods Described by Taylor in the Paper "Scientific Management"
In process industrial engineering, we have to identify methods of studying or observing elementary operations and improving them as well as analyzing and improving activities that take place at major operation level, process level and the factory level etc. Certain improvements have to occur at elementary operation level and certain improvements are factory level decisions and implemented across the factory.
In process improvement, industrial engineer must be able to explain his improvement clearly with numbers. An illustration of such explanation is given by Taylor.
Many people have questioned the accuracy of the statement that first-class workmen can load 47 1/2 tons of pig iron from the ground on to a car in a day. The following is the data relating to this work.
First. That our experiments indicated the existence of the following law: that a first-class laborer, suited to such work as handling pig iron, could be under load only 42 per cent of the day and must be free from load 58 per cent of the day.
Second. That a man in loading pig iron from piles placed on the ground in an open field on to a car which stood on a track adjoining these piles, ought to handle (and that they did handle regularly) 47 1/2 long tons (2240 pounds per ton) per day.
Additional facts.
47 1/2 long tons equal 106,400 pounds of pig iron per day.
At 92 pounds per pig, equals 1156 pigs per day.
42 per cent. of a day under load equals 600 minutes; multiplied by 0.42 equals 252 minutes under load.
252 minutes divided by 1156 pigs equals 0.22 minutes per pig under load.
A pig-iron handler walks on the level at the rate of one foot in 0.006 minutes. The average distance of the piles of pig iron from the car was 36 feet. It is a fact, however, that many of the pig-iron handlers ran with their pig as soon as they reached the inclined plank. Many of them also would run down the plank after loading the car. So that when the actual loading went on, many of them moved at a faster rate than is indicated by the above figures. Practically the men were made to take a rest, generally by sitting down, after loading ten to twenty pigs. This rest was in addition to the time which it took them to walk back from the car to the pile. It is likely that many of those who are skeptical about the possibility of loading this amount of pig iron do not realize that while these men were walking back they were entirely free from load, and that therefore their muscles had, during that time, the opportunity for recuperation. It will be noted that with an average distance of 36 feet of the pig iron from the car, these men walked about eight miles under load each day and eight miles free from load. These figures can be checked by multiplying them and dividing them, one into the other, in various ways, and one will find that all of the facts stated check up exactly.
Source: http://nraoiekc.blogspot.com/2013/08/illustrations-of-success-of-scientific.html
Source: http://nraoiekc.blogspot.com/2013/08/illustrations-of-success-of-scientific.html
Shoveling Productivity Science and Engineering
The foundation of the science of shoveling can be developed with perhaps 15 to 20 hours of thought and analysis by an average person interested in developing the science. The science is elementary.
For a first-class shoveler there is a given shovel load at which he will do his biggest day's work. What is this shovel load? This is a question which can be answered only through carefully made experiments. By first selecting two or three first-class shovelers, and paying them extra wages for doing trustworthy work, and then gradually varying the shovel load and having all the conditions accompanying the work carefully observed for several weeks by men who were used to experimenting, it was found that a first-class man would do his biggest day's work with a shovel load of about 21 pounds. For instance, that this man would shovel a larger tonnage per day with a 21-pound load than with a 24-pound load or than with an 18-pound load on his shovel. It is, of course, evident that no shoveler can always take a load of exactly 21 pounds on his shovel, but nevertheless, although his load may vary 3 or 4 pounds one way or the other, either below or above the 21 pounds, he will do his biggest day's work when his average for the day is about 21 pounds.
At the works of the Bethlehem Steel Company, for example, as a result of this law, it became necessary to provide some 8 to 10 different kinds of shovels, etc., each one appropriate to handling a given type of material not only so as to enable the men to handle an average load of 21 pounds, but also to adapt the shovel to several other requirements which become perfectly evident when this work is studied as a science. A large shovel tool room was built, in which were stored not only shovels but carefully designed and standardized labor implements of all kinds, such as picks, crowbars, etc. This made it possible to issue to each workman a shovel which would hold a load of 21 pounds of whatever class of material they were to handle: a small shovel for ore, say, or a large one for ashes. Iron ore is one of the heavy materials which are handled in a works of this kind, and rice coal, owing to the fact that it is so slippery on the shovel, is one of the lightest materials.
Some of the other elements go to make up the science of shoveling. Thousands of stop-watch observations were made to study just how quickly a laborer, provided in each case with the proper type of shovel, can push his shovel into the pile of materials and then draw it out properly loaded. These observations were made first when pushing the shovel into the body of the pile. Next when shoveling on a dirt bottom, that is, at the outside edge of the pile, and next with a wooden bottom, and finally with an iron bottom. Again a similar accurate time study was made of the time required to swing the shovel backward and then throw the load for a given horizontal distance, accompanied by a given height. This time study was made for various combinations of distance and height. With data of this sort before him, coupled with the law of endurance, it is evident that the man who is directing shovelers can first teach them the exact methods which should be employed to use their strength to the very best advantage, and can then assign them daily tasks which are so just that the workman can each day be sure of earning the large bonus which is paid whenever he successfully performs this task.
Bricklaying Improvement by Gilbreth
Mr. Frank B. Gilbreth became interested in the principles of scientific management, and decided to apply them to the art of bricklaying. He made an intensely interesting analysis and study of each movement of the bricklayer, and one after another eliminated all unnecessary movements and substituted fast for slow motions. He experimented with every minute element which in any way affects the speed and the tiring of the bricklayer.
He developed the exact position which each of the feet of the bricklayer should occupy with relation to the wall, the mortar box, and the pile of bricks, and so made it unnecessary for him to take a step or two toward the pile of bricks and back again each time a brick is laid.
He studied the best height for the mortar box and brick pile, and then designed a scaffold, with a table on it, upon which all of the materials are placed, so as to keep the bricks, the mortar, the man, and the wall in their proper relative positions. These scaffolds are adjusted, as the wall grows in height, for all of the bricklayers by a laborer especially detailed for this purpose, and by this means the bricklayer is saved the exertion of stooping down to the level of his feet for each brick and each trowel full of mortar and then straightening up again. Think of the waste of effort that has gone on through all these years, with each bricklayer lowering his body, weighing, say, 150 pounds, down two feet and raising it up again every time a brick (weighing about 5 pounds) is laid in the wall! And this each bricklayer did about one thousand times a day.
As a result of further study, after the bricks are unloaded from the cars, and before bringing them to the bricklayer, they are carefully sorted by a laborer, and placed with their best edge up on a simple
wooden frame, constructed so as to enable him to take hold of each brick in the quickest time and in the most advantageous position. In this way the bricklayer avoids either having to turn the brick over or end for end to examine it before laying it, and he saves, also, the time taken in deciding which is the best edge and end to place on the outside of the wall. In most cases, also, he saves the time taken in disentangling the brick from a disorderly pile on the scaffold. This "pack" of bricks (as Mr. Gilbreth calls his loaded wooden frames) is placed by the helper in its proper position on the adjustable scaffold close to the mortar box.
We have all been used to seeing bricklayers tap each brick after it is placed on its bed of mortar several times with the end of the handle of the trowel so as to secure the right thickness for the joint. Mr. Gilbreth found that by tempering the mortar just right, the bricks could be readily bedded to the proper depth by a downward pressure of the hand with which they are laid. He insisted that his mortar mixers should give special attention to tempering the mortar, and so save the time consumed in tapping the brick.
Through all of this minute study of the motions to be made by the bricklayer in laying bricks under standard conditions, Mr. Gilbreth has reduced his movements from eighteen motions per brick to five, and even in one case to as low as two motions per brick. He has given all of the details of this analysis to the profession in the chapter headed "Motion Study," of his book entitled "Bricklaying System," published by Myron C. Clerk Publishing Company, New York and Chicago; E. F. N. Spon, of London.
An analysis of the expedients used by Mr. Gilbreth in reducing the motions of his bricklayers from eighteen to five shows that this improvement has been made in three different ways:
First. He has entirely dispensed with certain movements which the bricklayers in the past believed were necessary, but which a careful study and trial on his part have shown to be useless.
Second. He has introduced simple apparatus, such as his adjustable scaffold and his packets for holding the bricks, by means of which, with a very small amount of cooperation from a cheap laborer, he entirely eliminates a lot of tiresome and time-consuming motions which are necessary for the brick-layer who lacks the scaffold and the packet.
Third. He teaches his bricklayers to make simple motions with both hands at the same time, where before they completed a motion with the right hand and followed it later with one from the left hand.
For example, Mr. Gilbreth teaches his brick-layer to pick up a brick in the left hand at the same instant that he takes a trowel full of mortar with the right hand. This work with two hands at the same time is, of course, made possible by substituting a deep mortar box for the old mortar board (on which the mortar spread out so thin that a step or two had to be taken to reach it) and then placing the mortar box and the brick pile close together, and at the proper height on his new scaffold.
These three kinds of improvements are typical of the ways in which needless motions can be entirely eliminated and quicker types of movements substituted for slow movements when scientific motion study, as Mr. Gilbreth calls his analysis, time study, as the writer has called similar work, are, applied in any trade.
Still many men would be skeptical as to the possibility of actually achieving any large results from a study of this sort. Mr. Gilbreth reports that a few months ago, in a large brick building which he erected, he demonstrated on a commercial scale the great gain which is possible from practically applying his productivity engineering. With union bricklayers, in laying a factory wall, twelve inches thick, with two kinds of brick, faced and ruled joints on both sides of the wall, he averaged, after his selected workmen had become skillful in his new methods, 350 bricks per man per hour; whereas the average speed of doing this work with the old methods was, in that section of the country, 120 bricks per man per hour. His bricklayers were taught his new method of bricklaying by their foreman. Each worker received a substantial (not a small) increase in his wages for his more productive work. With a view to individualizing his workmen and stimulating each man to do his best, Mr. Gilbreth also developed an ingenious method for measuring and recording the number of bricks laid by each man, and for telling each workman at frequent intervals how many bricks he had succeeded in laying.
Source: http://nraoiekc.blogspot.com/2013/08/illustrations-of-success-of-scientific_4.html
Still many men would be skeptical as to the possibility of actually achieving any large results from a study of this sort. Mr. Gilbreth reports that a few months ago, in a large brick building which he erected, he demonstrated on a commercial scale the great gain which is possible from practically applying his productivity engineering. With union bricklayers, in laying a factory wall, twelve inches thick, with two kinds of brick, faced and ruled joints on both sides of the wall, he averaged, after his selected workmen had become skillful in his new methods, 350 bricks per man per hour; whereas the average speed of doing this work with the old methods was, in that section of the country, 120 bricks per man per hour. His bricklayers were taught his new method of bricklaying by their foreman. Each worker received a substantial (not a small) increase in his wages for his more productive work. With a view to individualizing his workmen and stimulating each man to do his best, Mr. Gilbreth also developed an ingenious method for measuring and recording the number of bricks laid by each man, and for telling each workman at frequent intervals how many bricks he had succeeded in laying.
Source: http://nraoiekc.blogspot.com/2013/08/illustrations-of-success-of-scientific_4.html
Guarding Against Deterioration of Quality Due to Increase in Output
One of the dangers to be guarded against, when the pay of the man or woman is made in any way to depend on the quantity of the work done, is that in the effort to increase the quantity the quality is apt to deteriorate.
It is necessary in almost all cases, therefore, to take definite steps to insure against any falling off in quality before moving in any way towards an increase in quantity.
Source: http://nraoiekc.blogspot.com/2013/08/illustrations-of-success-of-scientific_9321.html
The four functions in the planning department as given by Taylor are: (1) route man and order-of-
work man; (2) instruction cards; (3) time and cost; (4) disciplinarian.
Motion-study is a subfunction of function No. 3 of the planning department. Motion-study is related to all subfunctions of the instruction-card function, but is most closely related to time-study and to the determining of methods of least waste. It is related to time-study in that it determines what path a motion is to follow, while time-study determines how swiftly the path is to be traversed and the amount of rest required to overcome resulting fatigue. The two measure work and determine the best method by which the work can be done. Motion-study, time-study, micromotion-study, fatigue-study, and cost-study are important measures of scientific management, by which the efficiency of each function and subfunction is determined, tested, and checked.
The unit to be chosen for intensive study and method used is determined by the amount of time and money that it is possible to save by the investigation. The work selected is divided into subdivisions of performance. Each subdivision is then subjected to motion study, to determine the best method to use in performing the work. This method is further divided into the smallest practicable units. These units are timed. The timed units are then again subjected to motion study, for more intensive study of method. Subdivided motions result. These are again timed, and so the process proceeds until the further possible saving will no longer warrant further study, or the available appropriation of time or money is exhausted. The most efficient motions, as determined by the tests of motion-study and time-study are then synthesised into a method of least waste.
As for the particular device by which the measurements are made, the choice depends mainly on the equipment available. Standards have been improved even by merely timing the work by counting, where no timing devices were at hand. Excellent work had been done with stop watches. But we advocate the use of micromotion study in all work demanding precision. Micromotion study consists of recording the speed simultaneously with a two or three dimensional path of motions by the aid of cinematograph pictures of a worker at work and a specially designed clock that shows divisions of time so minute as to indicate a different time of day in each picture in the cinematograph film.
The result of measurement, as outlined above, is standards synthesised from measured ultimate
units of the workers' manual motions.
A standard under modem scientific management is simply a carefully thought-out method of performing a function, or carefully drawn specifications covering an implement or some article of stores or of product. The idea of perfection is not involved in standardisation.
Motion study consists of dividing work into the most fundamental elements possible; studying these elements separately and in relation to one another; and from these studied elements, when timed, building methods of least waste. To illustrate, in the case of assembly of a machine, The existing method of assembling the machine is recorded in the minutest detail. Each element of the assembly is then tested, the method used in handling the element being compared with other possible methods. In this way, the most efficient elements of an assembly are determined ; and these elements are combined into a method of assembly that, because it is the result of actual measurement, is worthy to become a standard.
Such an assembly study was done on braider, manufactured by the New England Butt Company. As a result of motion studies made upon this, where eighteen braiders had been assembled by one man in a day, it became possible to assemble sixty-six braiders per man per day, with no increase in fatigue. This method consists of improved motions, and implies, first, changes in surroundings, equipment, and tools; and, second, changes in the type of worker assigned to do the work.
During the motion study of the assembly, it was found that more efficient motions could be made if the machine assembled was placed on a special table, which could be turned on its side and transformed into a lower table, after the base group of the machine had been assembled. It was also found that speed was gained and fatigue eliminated, when the parts of the machine were arranged in an obvious sequence on a vertical packet. These devices were immediately supplied at little cost and with great result in saving. Through these devices, and the other changes made by motion study, it became possible to accomplish nearly three and one-half times as much assembly as had previously been done. Such changes are typical, and it is typical that the inventions result from the motion study.
The quality of the output is maintained through a new type of inspection, which considers not only the output itself, but the elements, material and human, which result in that output. Nothing is a higher guarantee of quality than insistence on a standard method.
To find and apply the necessary measures for achievement and fatigue is primarily a task for the engineer. His training impresses him with the importance of measurement. His work makes him skilled in the use of measuring devices. Success in his profession depends chiefly upon the continued application of the most accurate measurement available, and this provides the incentive necessary for the maintenance of the scientific method. The engineer must secure the co-operation of the educator, the psychologist, the physiologist and the economist before he can hope to secure complete data, and to understand the full interpretation of what he finds.
The writers thus became impressed early with the importance of obtaining as accurate and detailed
records of methods as possible, if achievements were ever to be accurately measured.
The methods study was formulated into motion study, and divided into three parts:
1. Study of the variables of the worker.
2. Study of the variables of the surroundings, equipment and tools.
3. Study of the variables of the motion itself.
The writer's acquaintance with Dr. Taylor brought an added appreciation of the need for including time study with motion study. The great problem was to record the motions used along with time measurement. The cinematograph was finally resorted to as an accurate recording device. The invention of a special microchronometer that recorded times down to the millionth of an hour, made possible simultaneous records of this microchronometer and the positions of the worker whose activity was being studied.
The solution to the problem of efficiency or scientific management is to point out the job at which a man is a first-class man and put him in it.
Motion study shows the worker a new method of attack. The study has been done with the worker's co-operation. He has, through the study, learned how a motion problem is attacked, and he can apply the same method of attack to the minutiae of motions in his own work that the management has not had the time or the money to investigate.
Frank Gilbreth developed process analysis and improvement also along with motion study. In 1921, he presented a paper in ASME, on process charts. Lilian Gilbreth was a coauthor of this paper.
PROCESS CHARTS: FIRST STEPS IN FINDING THE ONE BEST WAY TO DO WORK
By Frank B. Gilbreth, Montclair, N. J. Member of the Society
and L. M. Gilbreth, Montclair, N. J. Non-Member
For presentation at the Annual Meeting, New York, December 5 to 9, 1921,
of The American Society of Mechanical Engineers, 29 West 39th Street, New York.
https://ia800700.us.archive.org/5/items/processcharts00gilb/processcharts00gilb_bw.pdf
At the end of the paper, the conclusion made is as follows:
The procedure for making, examining and improving a process is, therefore, preferably as follows:
a. Examine process and record with rough notes and stereoscopic diapositives the existing process in detail.
b. Have draftsman copy rough notes in form for blueprinting, photographic projection and exhibition to executives and others.
c. Show the diapositives with stereoscope and lantern slides of process charts in executives' theater to executives and workers.
d. Improve present methods by the use of —
1 Suggestion system
2 Written description of new methods or 'write-ups," "manuals," ''codes," ''written systems," as they are variously called
3 Standards
4 Standing orders
5 Motion study
6 Micromotion studies and chronocyclegraphs for obtaining and recording the One Best Way to do Work.
e. Make process chart of the process as finally adopted as a base for still further and cumulative improvement.
Note: Development in process improvement thought are being presented chronologically is reasonably brief way to place before the readers multiple approaches some of which are serial and hence have to be all used in a detailed process industrial engineering project. Some could be competing ideas, in which case, a choice needs to be made. The latter day texts, especially motion and time study or work study do not cover all the developments. Many industrial engineering graduates are not aware of some ideas because of that. So trying to present multiple ideas at one place can make many aware of the existence of many lines of thought.
In process industrial engineering, Certain improvements have to occur at elementary operation level and certain improvements are factory level decisions and implemented across the factory.
In process improvement, industrial engineer must be able to explain his improvement clearly with numbers. Otherwise many will not accept the new method.
An example of handling pig iron was given.
Answer:A shovel which would hold a load of 21 pounds of whatever material is to be shoveled. Different shovel design for different materials.
Thousands of stop-watch observations were made to study just how quickly a laborer, provided in each case with the proper type of shovel, can push his shovel into the pile of materials and then draw it out properly loaded.
Mr. Frank B. Gilbreth became interested in the principles of scientific management, and decided to apply them to the art of bricklaying.
He experimented with every minute element which in any way affects the speed and the tiring of the bricklayer.
Positions of Tools and Materials: He developed the exact position which each of the feet of the bricklayer should occupy with relation to the wall, the mortar box, and the pile of bricks, and so made it unnecessary for him to take a step or two toward the pile of bricks and back again each time a brick is laid.
Help of assisting laborer: Sorting of bricks by a laborer, and placing bricks with their best edge up on a simple wooden frame.
Motion improvement or method improvement. Mr. Gilbreth found that by tempering the mortar just right, the bricks could be readily bedded to the proper depth by a downward pressure of the hand with which they are laid.
Mr. Gilbreth has reduced movements required for bricklaying from eighteen motions per brick to five, and even in one case to as low as two motions per brick.
He has given all of the details of the study and analysis to the civil engineering profession in the chapter headed "Motion Study," of his book entitled "Bricklaying System."
He teaches his bricklayers to make simple motions with both hands at the same time, where before they completed a motion with the right hand and followed it later with one from the left hand.
Mr. Gilbreth calls his analysis, scientific motion study. Taylor has called similar work,time study.
Mr. Gilbreth used his new method in in a large brick building construction and operators achieved 350 bricks per man per hour; whereas the average was earlier 120 bricks per man per hour.
Mr. Gilbreth also developed an ingenious method for measuring and recording the number of bricks laid by each man, and for telling each workman at frequent intervals how many bricks he had succeeded in laying to give him an indication of higher earnings.
One of the dangers to be guarded against, when the pay of the man or woman is made in any way to depend on the quantity of the work done, is that in the effort to increase the quantity the quality is apt to deteriorate. It is necessary therefore, to take definite steps to insure against any falling off in quality due to process industrial engineering.
Motion-study is a subfunction of function No. 3 of the planning department related to specifying time and cost.
Motion-study, time-study, micromotion-study, fatigue-study, and cost-study are important measures of scientific management, by which the efficiency of each function and subfunction is determined, tested, and checked.
We advocate the use of micromotion study in all work demanding precision. Micromotion study consists of recording the speed simultaneously with a two or three dimensional path of motions by the aid of cinematograph pictures of a worker at work and a specially designed clock that shows divisions of time so minute as to indicate a different time of day in each picture in the cinematograph film.
A standard under modem scientific management is simply a carefully thought-out method of performing a function, or carefully drawn specifications covering an implement or some article of stores or of product. The idea of perfection is not involved in standardisation.
To illustrate, in the case of assembly of a machine, The existing method of assembling the machine is recorded in the minutest detail.
As a result of motion studies made upon this, where eighteen braiders had been assembled by one man in a day, it became possible to assemble sixty-six braiders per man per day, with no increase in fatigue.
Improvement. Machine assembled was placed on a special table, which could be turned on its side and transformed into a lower table.
The quality of the output is maintained through a new type of inspection, which considers not only the output itself, but the elements, material and human, which result in that output. Nothing is a higher guarantee of quality than insistence on a standard method.
The engineer must secure the co-operation of the educator, the psychologist, the physiologist and the economist before he can hope to secure complete data, and to understand the full interpretation of what he finds.
The methods study was formulated into motion study, and divided into three parts: 1. Study of the variables of the worker. 2. Study of the variables of the surroundings, equipment and tools. 3. Study of the variables of the motion itself.
The writer's acquaintance with Dr. Taylor brought an added appreciation of the need for including time study with motion study.
The operator can apply the same method of attack to the minutiae of motions in his own work that the management has not had the time or the money to investigate.
In 1921, he presented a paper in ASME, on process charts.
The Process Chart is a device for visualizing a process as a means of improving it.
The use of this process-chart procedure permits recording the existing and proposed methods and analysis of it without the slightest fear of disturbing or disrupting the actual work itself.
The aim of the process chart is to present information regarding existing and proposed processes in such simple form that such information can become available to and usable by the greatest possible number of people in an organization before any changes whatever are actually made, so that the special knowledge and suggestions of those in positions of minor importance can be fully utilized.
If any operation of the process shown in the process chart is one that will sufficiently affect similar work, then motion study (operation analysis) should be made of each part of the process, and the degree to which the motion study should be carried depends upon the opportunities existing therein for savings.
Improve present methods by the use of —
1 Suggestion system
2 Written description of new methods or 'write-ups," "manuals," ''codes," ''written systems," as they are variously called
3 Standards
4 Standing orders
5 Motion study
6 Micromotion studies and chronocyclegraphs for obtaining and recording the One Best Way to do Work.
38 Points
First posted on 30 July 2020
Updated on 16 August 2021, 3 August 2020
Source: http://nraoiekc.blogspot.com/2013/08/illustrations-of-success-of-scientific_9321.html
Gilbreth on Methods Study, Motion Study and Time Study
(In the book, Applied Motion Study, Collection of Essays by Gilbreth, 1917)The four functions in the planning department as given by Taylor are: (1) route man and order-of-
work man; (2) instruction cards; (3) time and cost; (4) disciplinarian.
Motion-study is a subfunction of function No. 3 of the planning department. Motion-study is related to all subfunctions of the instruction-card function, but is most closely related to time-study and to the determining of methods of least waste. It is related to time-study in that it determines what path a motion is to follow, while time-study determines how swiftly the path is to be traversed and the amount of rest required to overcome resulting fatigue. The two measure work and determine the best method by which the work can be done. Motion-study, time-study, micromotion-study, fatigue-study, and cost-study are important measures of scientific management, by which the efficiency of each function and subfunction is determined, tested, and checked.
The unit to be chosen for intensive study and method used is determined by the amount of time and money that it is possible to save by the investigation. The work selected is divided into subdivisions of performance. Each subdivision is then subjected to motion study, to determine the best method to use in performing the work. This method is further divided into the smallest practicable units. These units are timed. The timed units are then again subjected to motion study, for more intensive study of method. Subdivided motions result. These are again timed, and so the process proceeds until the further possible saving will no longer warrant further study, or the available appropriation of time or money is exhausted. The most efficient motions, as determined by the tests of motion-study and time-study are then synthesised into a method of least waste.
As for the particular device by which the measurements are made, the choice depends mainly on the equipment available. Standards have been improved even by merely timing the work by counting, where no timing devices were at hand. Excellent work had been done with stop watches. But we advocate the use of micromotion study in all work demanding precision. Micromotion study consists of recording the speed simultaneously with a two or three dimensional path of motions by the aid of cinematograph pictures of a worker at work and a specially designed clock that shows divisions of time so minute as to indicate a different time of day in each picture in the cinematograph film.
The result of measurement, as outlined above, is standards synthesised from measured ultimate
units of the workers' manual motions.
A standard under modem scientific management is simply a carefully thought-out method of performing a function, or carefully drawn specifications covering an implement or some article of stores or of product. The idea of perfection is not involved in standardisation.
Motion study consists of dividing work into the most fundamental elements possible; studying these elements separately and in relation to one another; and from these studied elements, when timed, building methods of least waste. To illustrate, in the case of assembly of a machine, The existing method of assembling the machine is recorded in the minutest detail. Each element of the assembly is then tested, the method used in handling the element being compared with other possible methods. In this way, the most efficient elements of an assembly are determined ; and these elements are combined into a method of assembly that, because it is the result of actual measurement, is worthy to become a standard.
Such an assembly study was done on braider, manufactured by the New England Butt Company. As a result of motion studies made upon this, where eighteen braiders had been assembled by one man in a day, it became possible to assemble sixty-six braiders per man per day, with no increase in fatigue. This method consists of improved motions, and implies, first, changes in surroundings, equipment, and tools; and, second, changes in the type of worker assigned to do the work.
During the motion study of the assembly, it was found that more efficient motions could be made if the machine assembled was placed on a special table, which could be turned on its side and transformed into a lower table, after the base group of the machine had been assembled. It was also found that speed was gained and fatigue eliminated, when the parts of the machine were arranged in an obvious sequence on a vertical packet. These devices were immediately supplied at little cost and with great result in saving. Through these devices, and the other changes made by motion study, it became possible to accomplish nearly three and one-half times as much assembly as had previously been done. Such changes are typical, and it is typical that the inventions result from the motion study.
The result of the introduction of motion standards is an increase in output and wages, and an accompanying decrease in cost and fatigue. The decreased cost and the increased wages both depend, of course, on the increased output. The output is increased, because the motions used to make any one unit of the output are less in number and more efficient in results.
The quality of the output is maintained through a new type of inspection, which considers not only the output itself, but the elements, material and human, which result in that output. Nothing is a higher guarantee of quality than insistence on a standard method.
To find and apply the necessary measures for achievement and fatigue is primarily a task for the engineer. His training impresses him with the importance of measurement. His work makes him skilled in the use of measuring devices. Success in his profession depends chiefly upon the continued application of the most accurate measurement available, and this provides the incentive necessary for the maintenance of the scientific method. The engineer must secure the co-operation of the educator, the psychologist, the physiologist and the economist before he can hope to secure complete data, and to understand the full interpretation of what he finds.
The writers thus became impressed early with the importance of obtaining as accurate and detailed
records of methods as possible, if achievements were ever to be accurately measured.
The methods study was formulated into motion study, and divided into three parts:
1. Study of the variables of the worker.
2. Study of the variables of the surroundings, equipment and tools.
3. Study of the variables of the motion itself.
The writer's acquaintance with Dr. Taylor brought an added appreciation of the need for including time study with motion study. The great problem was to record the motions used along with time measurement. The cinematograph was finally resorted to as an accurate recording device. The invention of a special microchronometer that recorded times down to the millionth of an hour, made possible simultaneous records of this microchronometer and the positions of the worker whose activity was being studied.
The solution to the problem of efficiency or scientific management is to point out the job at which a man is a first-class man and put him in it.
Motion study shows the worker a new method of attack. The study has been done with the worker's co-operation. He has, through the study, learned how a motion problem is attacked, and he can apply the same method of attack to the minutiae of motions in his own work that the management has not had the time or the money to investigate.
Process Charting for Improvement - Gilbreths' View (1921)
Frank Gilbreth developed process analysis and improvement also along with motion study. In 1921, he presented a paper in ASME, on process charts. Lilian Gilbreth was a coauthor of this paper.
PROCESS CHARTS: FIRST STEPS IN FINDING THE ONE BEST WAY TO DO WORK
By Frank B. Gilbreth, Montclair, N. J. Member of the Society
and L. M. Gilbreth, Montclair, N. J. Non-Member
For presentation at the Annual Meeting, New York, December 5 to 9, 1921,
of The American Society of Mechanical Engineers, 29 West 39th Street, New York.
https://ia800700.us.archive.org/5/items/processcharts00gilb/processcharts00gilb_bw.pdf
THE Process Chart is a device for visualizing a process as a means of improving it. Every detail of a process is more or less affected by every other detail; therefore the entire process must be presented in such form that it can be visualized all at once before any changes are made in any of its subdivisions. In any subdivision of the process under examination, any changes made without due consideration of all the decisions and all the motions that precede and follow that subdivision will often be found unsuited to the ultimate plan of operation.
The use of this process-chart procedure permits recording the existing and proposed methods and changes without the slightest fear of disturbing or disrupting the actual work itself.
The aim of the process chart is to present information regarding existing and proposed processes in such simple form that such information can become available to and usable by the greatest possible number of people in an organization before any changes whatever are actually made, so that the special knowledge and suggestions of those in positions of minor importance can be fully utilized.
Further detailed studies based on process chart
If any operation of the process shown in the process chart is one that will sufficiently affect similar work, then motion study should be made of each part of the process, and the degree to which the motion study should be carried depends upon the opportunities existing therein for savings.
If the operations are highly repetitive or consist of parts or subdivisions that can be transferred to the study of many other operations, then micromotion studies already made can be referred to; also new and further micromotion studies may be warranted in order that the details of method with the exact times of each of the individual subdivisions of the cycle of motions, or ''therbligs," as they are called,
that compose the one best way known, may be recorded for constant and cumulative improvement.
These synthesized records of details of processes (motion studies and micromotion studies) in turn may be further combined and large units of standard practice become available for the synthesis of complete operations in process charts.
At the end of the paper, the conclusion made is as follows:
The procedure for making, examining and improving a process is, therefore, preferably as follows:
a. Examine process and record with rough notes and stereoscopic diapositives the existing process in detail.
b. Have draftsman copy rough notes in form for blueprinting, photographic projection and exhibition to executives and others.
c. Show the diapositives with stereoscope and lantern slides of process charts in executives' theater to executives and workers.
d. Improve present methods by the use of —
1 Suggestion system
2 Written description of new methods or 'write-ups," "manuals," ''codes," ''written systems," as they are variously called
3 Standards
4 Standing orders
5 Motion study
6 Micromotion studies and chronocyclegraphs for obtaining and recording the One Best Way to do Work.
e. Make process chart of the process as finally adopted as a base for still further and cumulative improvement.
Note: Development in process improvement thought are being presented chronologically is reasonably brief way to place before the readers multiple approaches some of which are serial and hence have to be all used in a detailed process industrial engineering project. Some could be competing ideas, in which case, a choice needs to be made. The latter day texts, especially motion and time study or work study do not cover all the developments. Many industrial engineering graduates are not aware of some ideas because of that. So trying to present multiple ideas at one place can make many aware of the existence of many lines of thought.
Important Points from Part 2: Process Industrial Engineering - Methods and Techniques (Lesson 74)
Methods Described by Taylor in the Paper "Scientific Management"
In process industrial engineering, Certain improvements have to occur at elementary operation level and certain improvements are factory level decisions and implemented across the factory.
In process improvement, industrial engineer must be able to explain his improvement clearly with numbers. Otherwise many will not accept the new method.
An example of handling pig iron was given.
Shoveling Productivity Science and Engineering
What is the best shovel size for handling maximum quantity per throw?Answer:A shovel which would hold a load of 21 pounds of whatever material is to be shoveled. Different shovel design for different materials.
Thousands of stop-watch observations were made to study just how quickly a laborer, provided in each case with the proper type of shovel, can push his shovel into the pile of materials and then draw it out properly loaded.
Bricklaying Improvement by Gilbreth
Mr. Frank B. Gilbreth became interested in the principles of scientific management, and decided to apply them to the art of bricklaying.
He experimented with every minute element which in any way affects the speed and the tiring of the bricklayer.
Positions of Tools and Materials: He developed the exact position which each of the feet of the bricklayer should occupy with relation to the wall, the mortar box, and the pile of bricks, and so made it unnecessary for him to take a step or two toward the pile of bricks and back again each time a brick is laid.
Help of assisting laborer: Sorting of bricks by a laborer, and placing bricks with their best edge up on a simple wooden frame.
Motion improvement or method improvement. Mr. Gilbreth found that by tempering the mortar just right, the bricks could be readily bedded to the proper depth by a downward pressure of the hand with which they are laid.
Mr. Gilbreth has reduced movements required for bricklaying from eighteen motions per brick to five, and even in one case to as low as two motions per brick.
He has given all of the details of the study and analysis to the civil engineering profession in the chapter headed "Motion Study," of his book entitled "Bricklaying System."
He teaches his bricklayers to make simple motions with both hands at the same time, where before they completed a motion with the right hand and followed it later with one from the left hand.
Mr. Gilbreth calls his analysis, scientific motion study. Taylor has called similar work,time study.
Mr. Gilbreth used his new method in in a large brick building construction and operators achieved 350 bricks per man per hour; whereas the average was earlier 120 bricks per man per hour.
Mr. Gilbreth also developed an ingenious method for measuring and recording the number of bricks laid by each man, and for telling each workman at frequent intervals how many bricks he had succeeded in laying to give him an indication of higher earnings.
One of the dangers to be guarded against, when the pay of the man or woman is made in any way to depend on the quantity of the work done, is that in the effort to increase the quantity the quality is apt to deteriorate. It is necessary therefore, to take definite steps to insure against any falling off in quality due to process industrial engineering.
Gilbreth on Methods Study, Motion Study and Time Study
(In the book, Applied Motion Study, Collection of Essays by Gilbreth, 1917)Motion-study is a subfunction of function No. 3 of the planning department related to specifying time and cost.
Motion-study, time-study, micromotion-study, fatigue-study, and cost-study are important measures of scientific management, by which the efficiency of each function and subfunction is determined, tested, and checked.
We advocate the use of micromotion study in all work demanding precision. Micromotion study consists of recording the speed simultaneously with a two or three dimensional path of motions by the aid of cinematograph pictures of a worker at work and a specially designed clock that shows divisions of time so minute as to indicate a different time of day in each picture in the cinematograph film.
A standard under modem scientific management is simply a carefully thought-out method of performing a function, or carefully drawn specifications covering an implement or some article of stores or of product. The idea of perfection is not involved in standardisation.
To illustrate, in the case of assembly of a machine, The existing method of assembling the machine is recorded in the minutest detail.
As a result of motion studies made upon this, where eighteen braiders had been assembled by one man in a day, it became possible to assemble sixty-six braiders per man per day, with no increase in fatigue.
Improvement. Machine assembled was placed on a special table, which could be turned on its side and transformed into a lower table.
The quality of the output is maintained through a new type of inspection, which considers not only the output itself, but the elements, material and human, which result in that output. Nothing is a higher guarantee of quality than insistence on a standard method.
The engineer must secure the co-operation of the educator, the psychologist, the physiologist and the economist before he can hope to secure complete data, and to understand the full interpretation of what he finds.
The methods study was formulated into motion study, and divided into three parts: 1. Study of the variables of the worker. 2. Study of the variables of the surroundings, equipment and tools. 3. Study of the variables of the motion itself.
The writer's acquaintance with Dr. Taylor brought an added appreciation of the need for including time study with motion study.
The operator can apply the same method of attack to the minutiae of motions in his own work that the management has not had the time or the money to investigate.
Process Charting for Improvement - Gilbreths' View (1921)
In 1921, he presented a paper in ASME, on process charts.
The Process Chart is a device for visualizing a process as a means of improving it.
The use of this process-chart procedure permits recording the existing and proposed methods and analysis of it without the slightest fear of disturbing or disrupting the actual work itself.
The aim of the process chart is to present information regarding existing and proposed processes in such simple form that such information can become available to and usable by the greatest possible number of people in an organization before any changes whatever are actually made, so that the special knowledge and suggestions of those in positions of minor importance can be fully utilized.
If any operation of the process shown in the process chart is one that will sufficiently affect similar work, then motion study (operation analysis) should be made of each part of the process, and the degree to which the motion study should be carried depends upon the opportunities existing therein for savings.
Improve present methods by the use of —
1 Suggestion system
2 Written description of new methods or 'write-ups," "manuals," ''codes," ''written systems," as they are variously called
3 Standards
4 Standing orders
5 Motion study
6 Micromotion studies and chronocyclegraphs for obtaining and recording the One Best Way to do Work.
38 Points
First posted on 30 July 2020
Updated on 16 August 2021, 3 August 2020
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