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Man, Machines, Materials, Money, Technology and Time are the main resources required to produce goods and are to be deployed in the most effective manner
We have to select the best available combination of these resources at any point of time.
Method Study helps in analyzing the existing methods and develop a more efficient
method for future.
Method StudyMethod Study Method StudyMethod Study
Method Study is the systematic recording and critical examination of existing and proposed ways of doing work, as a means of developing and applying easier and more effective methods and reducing costs.
Definition And Objective of Method Definition And Objective of Method StudyStudy
Definition And Objective of Method Definition And Objective of Method StudyStudy
THE OBJECTIVES OF METHOD STUDY ARE THE OBJECTIVES OF METHOD STUDY ARE
Improvement of processes and procedures Improvement in the design of plant and equipment Improvement of plant layout. Improvement in the use of men, materials and
machines. Efficient materials handling Improvement in the flow of production and process. Economy in human effort and the reduction of
unnecessary fatigue. Method Standardization Improvement in safety standards. Development of a better physical working
environment
METHOD STUDY PROCEDURE METHOD STUDY PROCEDURE
The basic approach to method study consists of the following eight steps:
1. SELECT :- the work to be studied and define its boundaries.
2. RECORD :the relevant facts about the job by direct observation and collect such additional data as may be needed from appropriate sources.
3.EXAMINE the way the job is being performed and challenge its purpose, place, sequence and method of performance.
4. DEVELOP the most practical, economic and effective method.
5.EVALUATE different alternatives to developing a new improved method, and compare the cost-effectiveness of the selected new method with the current method of performance.6.DEFINE the new method in a clear manner and
present it to those concerned, management, supervisors and workers.
7.INSTALL the new method as standard practice and train the persons involved in applying it.
8.MAINTAIN the new method & introduce control procedures to prevent a drawback to the previous method of work.
These are the seven essential stages in the application of method study ; none can be excluded. Strict adherence to the sequence, as well as to their content, is essential for the success of an investigation. They are shown diagrammatically on the chart.
There are three factors that should be kept in mind when selecting a job.
1. Economic or cost-effective considerations.2. Technical considerations.3. Human considerations.
1. Economic considerations: It is obviously a waste of time to start or continue a
long investigation if the economic importance of a job is small.
Questions that should always be asked Will it pay to begin a method study of this job? Or
Will it pay to continue this study?
STEP 1: SELECTING THE WORK TO BE STUDIED
Obvious choices for study are:
A. Key profit-generating or costly operations or ones with the largest Scrap/waste rates.
B. Bottlenecks which are holding up other production operations, or lengthy operations that consume a great deal of time. C. Operations involving repetitive work using a great deal of labor
and ones that are likely to run for a long time. D. Movements of material over long distances between
workstations, those involving the use of a relatively large proportion of labor or which require repeated handling of material.
One of the easiest techniques that can be used to identify key operations as listed in part (A) is the Pareto analysis (sometimes also referred to as “the ABC analysis of value analysis”).
The same observation can be extended by saying that among all the
operations in a given plant a small number account for the largest share of cost or of profit, or the largest percentage of waste.
To illustrate the point we will consider the following example.
Let us assume that a certain enterprise produces 20 different products.Each of these products generates a certain profit.By listing the annual production and profit contribution one obtains the results shown in table 6.The next step consists of rearranging these items in descending order of importance according to profit. The result would then appear like the one shown in table 7.From table 7 it can be seen that three products only, listed as “A items”, account for 60 per cent of the profit. These are the most profitable and any improvement in methods of producing these particular products would reflect highly on profits. They would be a priority for study. Products listed under “B”, which are seven in number, contribute 25 per cent of the profit. They could then assume a second importance,while products “C” would command the last priority since their contribution to profit is minimal. The same type of analysis can be conducted to determine “the most costly products or processes” or “the products or processes that yield the highest waste”. Those would then become a priority for study by the work study specialist.
2. Technical or technological considerations:
One of the important considerations is the desire by management to acquire more advanced technology, i.e. in equipment or in processes.
Therefore, management may want to computerize its office paperwork or its inventory system, or to introduce automation in the production operations.
Before such steps are taken, a method study can point out the most important needs of the enterprise in this respect.
The introduction of new technology should therefore constitute an important factor in the choice of methods of work to be investigated.
3. Human considerations:
Certain operations are often a cause of dissatisfaction by workers. They may bring on fatigue or monotony or may be unsafe to
operate. The level of satisfaction should point to a need for method study. In
a similar fashion, a choice of a particular job for study may lead to anxiety or ill feeling. The suggestion given here is to leave it alone.
STEP 2: RECORDING THE FACTS
The next step in the basic procedure, after selecting the work to be studied, is to record all the facts relating to the existing methodThe success of the whole procedure depends on the accuracy with which the facts are recorded, because they will provide the basis of both the critical examination and the development of the improved method Recording techniques – known as CHARTS and DIAGRAMS Charts and diagrams broadly grouped as:
PROCESS SEQUENCES includes the following CHARTSPROCESS SEQUENCES includes the following CHARTS
OperationProcess Chart Flow Process
ChartMan , Material
andEquipment Type
Two HandedProcess Chart
Process Chart Symbols…Process Chart Symbols…Process Chart Symbols…Process Chart Symbols…
Indicates the main steps in a process, method or procedure.Indicates the main steps in a process, method or procedure.Usually the part, material or product concerned is modified or Usually the part, material or product concerned is modified or
changed during the operation. changed during the operation.
InspectionInspection
Indicates an inspection for quality and / or check for quantityIndicates an inspection for quality and / or check for quantity
OperationOperation
TransportTransport
Indicates the movement of workers, materials or equipment from place Indicates the movement of workers, materials or equipment from place to placeto place
Temporary Storage or DelayTemporary Storage or Delay
Indicates a delay in the sequence of events : for example, work waiting Indicates a delay in the sequence of events : for example, work waiting between consecutive operations, or any object laid aside temporarily without between consecutive operations, or any object laid aside temporarily without
record until required. record until required.
Permanent StoragePermanent Storage
Indicates a controlled storage in which material is received into or issued Indicates a controlled storage in which material is received into or issued from a store under some form of authorization; or an item is retained for from a store under some form of authorization; or an item is retained for reference reference purposes.purposes.
Process Chart Symbols…Process Chart Symbols…Process Chart Symbols…Process Chart Symbols…
The Outline Process Chart The Outline Process Chart
An outline process chart is a process chart giving an overall An outline process chart is a process chart giving an overall picture by recording in sequence only the main operations and picture by recording in sequence only the main operations and inspectionsinspections
It does not portray the details – delays , movements, and storage It does not go into the details of the details of the place of activity, the person who performs it, or the physical means of achievement In making an outline process chart we start with a vertical line down the right hand side of the page to show the operations and inspections undergone.
The Outline Process Chart- Example The Outline Process Chart- ExampleFor the purpose of illustration , the case of the repair of a bicycle is taken.
In this example it is assumed that the bicycle had been involved in a minor accident and required restricted repairs to the front wheel, the left pedal and the steering handle.
The Outline Process Chart would be
OBSERVATIONS OBSERVATIONS
After operation number 15, the next operation shown is number 23. Operations 16 to 22 are covered by the seven repetitions of operation 15. Similarly , the gap between Inspection number 3 and 11 is accounted for by the seven repetitions of inspection 3.
FLOW PROCESS CHART (FPC)FLOW PROCESS CHART (FPC)
It is a process chart setting out the sequence of the flow of a product or procedure by recording all events under review using appropriate process chart symbols.
BENEFITS: In identifying ways of improving the process by eliminating unnecessary idle time, minimizing the distances things must be moved or rearranging tasks for greater efficiency
Three types of flow process chartsThree types of flow process charts
MAN TYPE: Flow chart which shows the actions of a person
MAN TYPE: Flow chart which shows the actions of a person
MATERIAL TYPE: Flow chart which shows what happens to a product or item
MATERIAL TYPE: Flow chart which shows what happens to a product or item
EQUIPMENT TYPE: Flow chart which shows how a tool or other piece of equipment is used
EQUIPMENT TYPE: Flow chart which shows how a tool or other piece of equipment is used
Flow Process Charts- Material TypeFlow Process Charts- Material Type
An FPC (Matrl) sets out the sequence of flow of a product or a document , recording all the events that affect the material or document being processed.
Illustration : The process of charging of batteries by Umesh Motors(P) Ltd. Is as follows. Customers deposit discharged automobile batteries at the Reception Bay of the workshop, and obtain a receipt. After three days, they collect their respective batteries from the Delivery Bay of the workshop, on presentation of the receipt and payment of service charges. The reception clerk marks each battery with a customer-identification number.He stacks the batteries on a steel shelf.
The chargeable batteries are collected twice a day from the Reception Bay by mazdoor Dharam. He transports the batteries on a stillage truck , and delivers them to the charging shop, which is 50 meters away from the Reception Bay.
The chargeable batteries are collected twice a day from the Reception Bay by mazdoor Dharam. He transports the batteries on a stillage truck , and delivers them to the charging shop, which is 50 meters away from the Reception Bay.
At the Charging Shop , the battery is tested, cell by cell , for voltage and specific gravity. The cells are ‘topped up’ to the correct level. The battery is then moved to the charging bench, and placed on charge by connecting the terminals to the bus bars. While on charge , it is tested every four hours for specific gravity. On completion of charging, which is determined by the specific gravity of the electrolyte , the connections to the bus bars are removed.The battery is tested for voltage of each individual cell.It is then placed on a stillage(small wooden platform with low legs)
At the Charging Shop , the battery is tested, cell by cell , for voltage and specific gravity. The cells are ‘topped up’ to the correct level. The battery is then moved to the charging bench, and placed on charge by connecting the terminals to the bus bars. While on charge , it is tested every four hours for specific gravity. On completion of charging, which is determined by the specific gravity of the electrolyte , the connections to the bus bars are removed.The battery is tested for voltage of each individual cell.It is then placed on a stillage(small wooden platform with low legs)
Mazdoor Dharam collects a stillage of charged batteries and transports them, by a stillage truck, to the delivery bay , which is 35 meters away from the charging shop . Here the Delivery Clerk takes over the batteries and places them on a steel rack.
Mazdoor Dharam collects a stillage of charged batteries and transports them, by a stillage truck, to the delivery bay , which is 35 meters away from the charging shop . Here the Delivery Clerk takes over the batteries and places them on a steel rack.
Flow Process Charts- Man TypeFlow Process Charts- Man Type
An FPC(Man), sets out the sequence of activities of an individual performing a task under study .
Only four symbols are employed- operation , inspection, delay, transport
TWO HANDED PROCESS CHARTSTWO HANDED PROCESS CHARTS
Two handed process charts is a chart in which the activities of a worker’s hands individually(or limbs) are recorded in the relationship to one another
SYMBOLS AND THEIR DESCRIPTIONS FOR TWO HANDED CHARTS
OperationOperation
Is used for activities for grasp, position, use, release Is used for activities for grasp, position, use, release etc. of a tool, component or materialetc. of a tool, component or material
TransportTransport
To represent the movement of hand to or from the work, or a tool, or material
Temporary Storage or DelayTemporary Storage or Delay
Denotes time during which the hand being charted is idle (although the others may be in use)
HOLDHOLD
In two handed process chart , hold is used to represent the activity of holding work , tool or material i.e when the hand being charted is holding something
MULTIPLE ACTIVITY CHART
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 interrelationship
Useful in organizing teams of operatives on mass production work and also on maintenance work when expensive plant cannot be allowed to remain idle longer
Time (Hours) WORKER 1 WORKER 2 WORKER 3 WORKER 4
5
10
15
20
25
30
35
Disassembly of lathe Disassemble lathe. Head stock, bed, fed and lead screws, carriage and tailstock
Disassemble head stock, Remove main spindle, speed change mechanisms, and change gears.
Idle
Inspection to determine fault
Wash with thinner to remover grease and clean parts
Repair carriage bed and lay out screw, nuts, etc.
Repair and assembly of feed gear box
Repair carriage bed, check and repair feed screw and apron of the carriage.
Repair and assemble feed gear box
Grind lathe beds
Fit saddle to bed
Assemble tailstock
Assemble and mount bed and headstock on stand
Repair carriage way and lay out screw, nuts, etc.
Assemble tailstock.
Idle
Fit cross slide and top slide
Assemble cooling system
Repair and assembly of apron
Install electric motor
Install feed gear box, apron and feed rod
Installing feed gear box apron and feed red
Mount electric motors and fit reservoirs
Running in and finishing Run in and finish Run in and finish
Testing the lathe Test and calibrate assembly
MAN-MACHINE CHART
Variant of Multiple Activity Chart
Present a picture of the operations performed simultaneously by a man and one or more machines
Useful for
1. Better coordination between man and machine
2. Reduction / elimination of idle times of man and
machine to improve the utilization
3. Exploration of alternative man-machine
arrangements suitable to the plant conditions
TIME
Min.
Man Machine
2 Remove finished casting clean with compressed air
Idle
4 Gauge depth on surface plate
5
6
Break sharp edge and clean with compressed air
8 Place in box obtain new casting
10 Clean machine with compressed air
12 Locate castig in fixture: start machine and automatic feed
15 Idle Mill second face
20
EXAMPLE
Draw a man – machine chart showing one man(the operator) operating two semi-automatic lathes. The cycle consists of load M/C , ½ min., Machine part , 1 min (the machine stops automatically at the end of cut) and unload Machine, ¼ min. The two machines are alike and each completes the machining operation and stops automatically. The man-machine chart is to show the operator starting the machines in the morning with both machines empty and continues until each machine completes two cycles, i.e. it has machined two pieces. The man-machine chart should have one column for the man and a column each for machine 1 and machine 2.
CONTD..
DIAGRAMS INDICATING MOVEMENTS
•String Diagram•Travel Charts•Flow Diagrams
STRING DIAGRAM
Observe the clusters of points, pins, turning points. Also observe the grid lines which represent a measure of the
distance between the points. Red is the staring point and yellow is the ending point
CONSTRUCTION OF A STRING DIAGRAM
Step-1 Produce a scale map of the work area Identifying all machines, furniture and other equipments in
the diagram that can be moved. These could be shaped as pieces of card that can be pinned to the work area map
Step-2 Identify the points in the process where actions take place
and also identify the doorways, pillars etc that effect the path movements and mark the positions of these on the map with map pins and action symbols.
Step-3 Tie the end of a pieces of string to the pin where the process
starts and then wrap it around each pin in turn, following the movement around the process
CONTINUE………………………..
Step-4 Mark the string at the start and finish points, using
a pen. Step-5
Measuring between the pen marks, will give the total distance travelled during the process.
Step-6 Rearrange the movable items on the map, aiming
to reduce the total distance
Mobility:- Rearrange items and movements around fixed or immovable items such as heavy machines.
Function:- Put machines or people together that perform the same function. This is useful when varying loads may be between machines.
Product:- Put machines or people together that make the same product. This works well when each machine is used for only one product.
Strategies for deciding layouts include:
TRAVEL CHART A travel chart is a tabular record for presenting
quantitative data about the movements of workers, materials or equipment between any number of places over any given period of time.
The travel chart also identifies movement, when movements along complex paths are involved.
WHY TRAVEL CHART ?
Although the string diagram is a neat and effective way of record the movement of worker or material
o They take long time to construct ;o Look increasingly like a complex maze with increasing
complexity of movement paths.
When the movement patterns are complex, the travel chart is quicker and more manageable to record.
Count of occurrence
Distance between places
FLOW DIAGRAM
While the flow process chart describes the flow of a product or process, it is generally supplemented with a flow diagram.
While the flow process chart records travel distances and time taken for various operations, the flow diagram is a plan , drawn to scale of the work area, correctly indicating the position of machines and working positions.
The example shown indicates the flow diagram of receiving, inspection, marking and storing materials.
IMPROVED FD OF INSPECTION AND MARKING
Types of Jobs Examples Recording Technique
Complete Sequence of manufacture
•Manufacture of an electric motor from raw material to dispatch; •Transformation of thread into cloth from preparation to inspection;• Receipt, packing and dispatch of fruit
Outline process chartFlow process chartFlow diagram
Factory layout : movement of materials
•Movements of a diesel engine cylinder head through all machining operations. •Movements of grain between milling operations.
Outline process chartFlow process chart material typeFlow diagramTravel chart
Suitability of different recording techniques:-
Types of Jobs Examples Recording Technique
Factory layout : movement of workers
Laborers servicing spinning machine with bobbins
Cooks preparing meals in a restaurant kitchen
Flow process chart-man typeString diagram
Handling of materials
Putting materials into and taking them out of storesLoading lorries with finished products.
Flow process chart – material typeFlow diagramString diagram
Workplace layout Light assembly work on a benchTypesetting by hand
Flow process chart-man type.Two-handed process chart. Multiple activity chart.
Continue…………………..
Types of Jobs Examples Recording Technique
Gang work or automatic machine operation
Assembly line Operator looking after semi-automatic lathe
Multiple activity chartFlow process chart-equipment type
Movements of operatives at work
Female operatives on short – cycle repetition workOperations demanding great manual dexterity
Multiple activity chartFlow process chart – equipment type
Continue…………………..
EXAMINE
The questioning technique is the means by which the critical examination is conducted, each activity being subjected in turn to a systematic and progressive series of questions.
PRIMARY QUESTIONS
The PURPOSE for which
The PLACE at which
The SEQUENCE in which
The PERSON by whom
The MEANS by which
THIS EXAMINATION SEEKS TO
the recorded activities
Identify possibility of
ELIMINIATING
COMBINING
REARRANGING
OR
SIMPLIFING
INSTALLATION OF THE NEW METHOD
The success of method study is realized when actual change is made on ground.
The first part of installation is to define the new method by preparing ‘the written standard practice.
This method is perhaps the most difficult step of method study procedure as it needs reassuring, retraining and supporting through acquisition of new skills.
New method involves gaining approval of following personnel for the changes suggested:
1. Concerned department supervision
2. Works and general management
3. Workers and their representatives
The install Phase in some cases, will require a parallel running of old and new systems.
While in other cases it may require the build up of buffer – stocks.
It may also require changes in procedures, or minor addition of equipment and process.
Thus, the successful introduction of new working methods is extremely important because very often there is only one chance to make change.
MAINTAIN THE NEW STANDARD
After the introduction of new working methods, it is necessary to check and verify that the new method is working and is it bringing the desired results or not. This is the maintain phase.
Proper control procedures are used to ensure that new method is practiced to achieve the benefits of method study and also to achieve higher productivity.
One of the common problems of maintaining the new standard is method drift.
At last, installation is to be preceded by retraining the workers to operate new methods. Close contact with the progress of the job must be maintained, till it is performed.
FINAL EXAMPLE
Here I took an example of car manufacturing process.
As first step is to select the work is to be studied. Here I select the process of car manufacturing.
Step-1 select, manufacturing process of car
STEPS INCLUDE IN MANUFACTURING PROCESS
Parts are produced in various plantsStart with the frameInstalling the partsEngine and Transmission InstalledBuilding the ShellFinal Body ComponentsInspection and WashingPaintThe Inner WorkingsThe Shell and the FrameTest the Car
RECORDING OF WORK Suppose, here I used string diagram to record the
work.
Plants
`
EXAMINE
Here assume that total length of thread is 30cm and therefore total distance has to covered within the process is 30*100= 3000 m. More distance means more time and more time mean more cost.
So improvement is required to reduced the distance.
After considering all activities. It can be seen that all machineries are movable. So here we rearrange all machineries and after that will see the synergy.
INSTALLATION, MAINTANCE OF NEW SYSTEM
Before installation of new plan Length of thread Distance Time Cost
Of the new model should be measure and compare with the original one
If profitable then install the new plan and maintain it through regular check on it