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WORK STUDY 1. Define Productivity and work study and explain the relation between them. What are the techniques of work study? Productivity: Productivity may be defined as the ratio between output and input. Work study: Work study is the investigation, by means of a consistent system of the work done in an organisation in order to attain the best utilization of resources i.e. materials, machines, men and money. All the technologies and management systems are related with productivity. Work study is one the basic techniques of improving productivity. Work study is the generalized name used to describe a complete set of techniques through which work can be similised, standardized and measured. Work study investigates the work done in an organisation and it aims at finding the best and most effective way of utilizing the available resources. Work study and Productivity: Work study indicates how effectively utilize the resources. The resources may be men, material, machine and money. As it is evident from the work study that it reduces the wastage of time increases the efficiency of man and machines, so this technique leads to increase the productivity of the system. Productivity implies constant urge to find better, easier, cheaper, quicker and safer method of doing a job, manufacturing product or providing a service. But it is quite clear that most of these objectives can be achieved by different activities of work study, i.e. the economic position of our country can be improved in comparison to other countries if we improve our productivity and performance in various fields. In brief work study is organized and continued effort to improve productivity and quality to reduce cost. For this objective work study engineer must lead the way in effective utilization of resources i.e. man, machine, materials and money. Techniques of Work study: Basically there are two techniques, method study and work measurement. Work study is the term used to embrace the techniques of method study and work measurement, which are used to ensure the best utilization of man power and material resources in carrying out specified activity.

2. What is meant by method study, its objectives and steps involved (i.e. procedure of method study)? Method study: Method study is basically conducted to simplify the work and working methods and must go towards higher productivity. It is always desirable to perform the requisite functions with desired goal and with minimum consumption of resources method signifies how a work is to be done i.e., description of how we consume resources in order to achieve our target. Objectives: 1. Better design of plant equipment and buildings. 2. Less fatigue to workers by avoiding unnecessary movements of man power.

3. 4. 5. 6. 7.

Better working conditions and environment for workers. To have more effective and environment for workers. To have more effective utilization of materials, machines, money and manpower. Better product quality. Efficient and fact material handling equipment.

Procedure of Method study: 1. Selection of work or job to be studied. 2. Collection and recording of necessary information. 3. Critical examination of the existing method. 4. Develop the new improved method. 5. Install the improved method. 6. Maintain the improved method.

3. What are the recording techniques of method study? Recording Techniques: 1. Charts indicating process sequence: a. Outline process chart b. Flow process chart (man type, material type, and equipment type) c. Two handed process chart d. Gang process chart 2. Charts using a time scale: a. Multiple activity chart b. SIMO chart 3. Diagrams indicating movement a. Flow diagram b. String diagram c. Cycle graph d. Chromo cycle graph e. Travel chart 4. Define: outline process chart, flow process chart – man type, material type, machine type, flow diagram, two handed operation chart, two hand process chart, multiple activity chart, man-machine chart? 1. Outline process chart: It is a process chart giving an overall picture (birds eye view) of whole process, by recording in sequence only the main operation and inspections. 2. Flow process chart: It is the process chart setting out of the flow of products or a procedure by recording all events under the review using appropriate process chart symbols. 3. Man type flow process chart: It records ‘what a worker does’. 4. Material type flow process chart: It records ‘what happens to the material’. 5. Equipment type flow process chart: It records ‘how the equipment is used’. 6. Flow diagram: A flow diagram is a pictorial layout of buildings and floors on which locations of all the activities as given on the flow lines representing the movement of men and materials as shown. Such pictorial layout is valuable in incorporating improvement in the method. The number of movements if minimized results a lot of saving both in cost and efforts to perform this job. 7. Two handed process chart: It is a process chart in which the activities of a worker’s hand are recorder in their relationship to each other.

8. Multiple Activity Chart: It is a chart on which the activities of more than one object (worker, machine or equipment) are each recorded on a common time scale to show their inter relationship. 9. Man-Machine Chart: A multiple activity chart is a chart on which the activities of more than one subject (worker, machine or equipment) are each recorded on a common time scale to show their inter-relationship. The activity chart is of special value for analyzing maintenance work, jobs involving people working in groups, and operations where the work is unbalanced and where there is necessary idle time.

Give the examples of the above charts? Outline process chart: Assembling a switch rotor. Flow process type: 1. Man type: manufacture of relief value assembly of ball point pen, charging refill. 2. Machine type: machining of components. 3. Simple flow diagram: A simple flow diagram in which raw material, from the store moves to work station P where an operation is performed the semi-finished products moves to work place where another operation is carried out hence it moves to work place R inspection and is further sent to location S where it waits for a short period and ultimately goes out of unit. 4. Two handed process chart: Assembling bolt and nut cutting glass tube, pin-board exercise, assembly of power motor starting.

What are the process symbols? Give examples for what is the process used in outline process chart, flow process chat, two handed process chart? Process chart symbols: Process charts are the graphical representations or diagrams or pictures which given an overall view of a process. Process chart are denoted by symbols. The symbols give a better understanding of the facts. Following are the various symbols to record various events. Event Symbol Description Operation It represents an action Storage

Delay Transport Inspection

D

It represents a storage when materials (raw or semi finished goods awaits an action). It represents a temporary halt in the process It represents movement of an item It represents an act of checking

Outline process chart: It is also known as operation process chart and it provides a compact overall view of the whole system of operations involved in the production of a product. In this main activities (i.e. operations and inspections) carried out to complete a job are recorded in the sequence of

their occurrence but irrespective of where they are performed and who performs them and symbols used are: Event Symbol Description Operation It represents an action Inspection

It represents an act

Process chart symbols used in flow process chart: It utilizes symbols of operation, transportation, inspection, delay and permanent storage. Event Symbol Description Operation It represents an action Storage

It represents a storage when materials awaits an action. It represents an act

Inspection Delay

D

Transport

It represents a temporary halt in the process It represents movement of an item

Process chart: Symbols used in two handed process chart: Event Symbol Description Operation It represents an action Storage Delay Transport

D

It represents a storage when materials awaits an action. It represents a temporary halt in the process It represents movement of an item

What are THERBLINGS? Where do you use them? THERBLINGS is a term originated by Frank Gilbreth to describe the basic elements of movements or fundamental hand motions of the work cycle. It is also sometimes referred to a fundamental element or sub division of work. THERBLINGS is represented by a symbol, a definite colour and with a word. THERBLINGS are used to record activities that are occurred in filming.

What is meant by micro motion and memo motion study? Micro motion study: It means the study of micro motions known as THERBLINGS. Each human activity is supposed to get divided or split into these small moments. The purpose of the study is to found an operative one best pattern of moments, which involves less efforts, time and fatigue to accomplish a task.

Memo motion study: It was introduced by M.E.Mandel. It is a special type of micro-motion study in which the activities are filmed at a much lower speed, say that 60 or 70 frames per minute. Steps involved in memo motion are: 1. Study of operation to be filmed. 2. Prepare the film. 3. Analyze the film.

What is a SIMO chart? First abbreviate it? Where do you use it? SIMO chart: A SMIO chart is short form of Simultaneous Motion Cyclic Chart. SIMO chart is generally utilized for micro-motion analysis of: 1. Short cycle repetitive job 2. High order skill job This chart find in application in job like component assembly, inspection repetitive use of job jigs and fixtures, packing procedure. A SIMO chart shows relationship between different limbs of workers at any instant it can be found what one hand is doing with respect to other in terms of THERBLINGS. Principles of Motion economy: 1. Principle of motion economy as related to use of human body. 2. Principle of motion economy as related to use of work place layout. 3. Principle of motion economy as related to design of tools and equipment.

What is meant by work measurement, its objectives, and steps involved (i.e. procedure of work measurement? Work measurement: Work measurement may be defined as “the art of observing and recording the time required to do each detailed element of an industrial activity or operation.” The term industrial activity includes, mental, manual and machining operation where: 1. Mental time includes time taken by an operator for thinking over some alternative operations. 2. Manual time consist of three types of operations i.e. related with handling of materials, handling of tools, handling of machines. 3. Machining time includes time taken by the machines in performing the requisite operations. Objectives: 1. Target time for each job can be scientifically estimated with these estimate realistic schedules and man power requirements can be prepared. 2. Sound comparison of alternative methods is possible by comparing their basic times. 3. Useful wage incentive schemes can be formulated on the basis of target times. 4. It can lead to proper balancing of the work distribution. 5. To standardise the efficient method of performing operations. 6. To standardise conditions for efficient performance. 7. To determine man and machines ratio for effective and efficient utilization of bath.

Steps involved in work measurement: 1. Select the job for study and define the objective of the study. This needs statements of the use of results, precision require and the desired level of confidence in the estimated time. 2. Analyze the operation to determine if the standard method and conditions exists and the worker is properly trained. The method study or training of operator should be completed before starting time study if need be. 3. Select the operator to be studied if more than one can perform the task. 4. Record the information about the standard method, operator, operation, product machine, quality required and work conditions. 5. Divide the operation into reasonably small elements. 6. Time the operator for each of the element. Estimate the total number of observations to be taken. 7. Collect and record the data of required number of cycles by way of timing and rating the operator. 8. For each element of operation note the representative watch time and calculate the normal time as follows. Normal time = observed time x rating factors 9. Determine standard time by adding allowanced to normal time of operation. Some allowances such as personnel allowances (20%), fatigue allowances (5%), preparation allowances (5%) are generally used for these can be taken from the company’s policy book or by conducting an independent study. 10. Thus, standard time = normal time + allowances

What is meant by rating an operator? What are the techniques used for rating? Rating is the assessment of workers rating of working relative to the observers concept of the rate correspond to standard pace. Various rating techniques or systems are as follows: 1. Speed rating 2. Skill and effort rating 3. Westing-house system of rating 4. Systematic rating 5. Objective rating 6. Physiological evaluation of time study

Explain the steps involved in time study? What is Time study equipment? Steps involved in time study: 1. Identify the job to be time studied and the operations to be timed. 2. Obtain the improved procedure of doing the job from the method study department. 3. Select the worker for study. 4. Take the workers as well as the shop supervisor into confidence and explain to them the objectives of the study. 5. Collect the equipment and arrange machinery, jigs, fixtures, etc, required to conduct time study and ensure their accuracy. 6. Explain to the worker the improved working procedure and the use of tools, jigs, fixture and other attachment to the job. 7. Break the job into operations and operators into element and write them on the proper form. Also separate constant elements from variable elements. 8. Determine the number of observations to be timed for each element.

9. Conduct the observations and record them on the time study form. 10. Also rate the performance of the worker during step-9. 11. Repeat steps 9 and 10 for taking more than one observations. 12. Complete observed time from measure of central tendency. 13. Calculate observed time by using performance rating factor. 14. Add process allowances, rest and personnel allowances and special allowances in normal time to obtain standard time or allowed time. Time study equipment: 1. A stop watch 2. A time study board 3. Time study forms 4. Pencil, rubber, steel rule, tachometer, micro meter, calculator, etc.

What are the time allowances to be provided for workers? Define them and give appropriate percentages? An amount of time added to the normal time to provide for personnel delays, unavoidable delays and fatigue of the operator. Allowances when added to the normal time, it results in standard time. 1. Personal allowances: A worker cannot work continuously, like a machine and hence personnel allowance is provided to him, in order to satisfy his personnel needs like drinking water, trip to dressing room, etc. 2. Fatigue allowance: Fatigue may be defined as a physical or mental weariness, real or imagined, existing in a person and adversely affecting his ability to perform work, fatigue, rest relaxation allowance will give to worker to overcome fatigue allowance. 3. Process allowance: It is an allowance to compensate for enforced idleness. During process it may be likely that the operator is forced to be idle due to certain reasons. a. When operator is running automatic machines, then the operator is idle after loading the machine. b. When one operator is running more than one machine. Description Personal allowance Basic fatigue allowance Bad light Mental strain Atmospheric conditions (lack of ventilation, bad smell, fumes, dust, smoke)

Allowance 5% 4% 1-5% 1-8% 1-10%

What is meant by observed time, normal time, work content and standard time? Represent the calculation of standard time for completion of a job by diagram? Observed time: The actual time taken in the completion of the operation, commonly it is a total of the elemental time. The elements are so chosen as to be dependent on only one variable and which lies within the field of observations.

Normal time: It is the product of observed time and rating factor. Normal time = observed time x rating factor /100 Work content: It is sum of normal time and relaxation allowances. Work content = Normal time + relaxation allowance Standard time: Standard time is the total time in which a job should be completed at standard performance. Standard time = work content + other allowances

What is meant by work sampling? What are its applications? Work sampling: Work sampling is a technique in which a large number of observations are made over a period of time of one or group of machines, process, or workers. Each observation recorded for a particular activity or delay in a measure of the 1% of time during which that activity or delay occurs. It contains what % of the working day, a person spends how. Applications: 1. To determine idle time and working time of man and machine. 2. To estimate allowances for unavoidable delay. 3. For setting time standard....