Symbols Used in Method Study
Method study enables the industrial engineer to subject each operation to systematic analysis. The main purpose of method study is to eliminate the unnecessary operations and to achieve the best method of performing the operation. Method study is also called methods engineering or work design.
Symbols Used in Method Study:
Graphical method of recording was originated by Gilberth, in order to make the presentation ofthe facts clearly without any ambiguity and to enable to grasp them quickly and clearly. It isuseful to use symbols instead of written description.
METHOD STUDY SYMBOLS
An operation occurs when an object is intentionally changed in one or more of its characteristics (physical or chemical). This indicates the main steps in a process, method or procedure. An operation always takes the object one stage ahead towards completion.
Examples of operation are:
- Turning, drilling, milling, etc.
- A chemical reaction.
- Welding, brazing and riveting.
- Lifting, loading, unloading.
- Getting instructions from supervisor.
- Taking dictation.
An inspection occurs when an object is examined and compared with standard for quality and quantity. The inspection examples are:
- Visual observations for finish.
- Count of quantity of incoming material.
- Checking the dimensions.
A transport indicates the movement of workers, materials or equipment from one place to another.
Example: Movement of materials from one work station to another.
Workers travelling to bring tools.
Delay (Temporary Storage)
A delay occurs when the immediate performance of the next planned thing does not take place.
Example: Work waiting between consecutive operations.
Workers waiting at tool cribs.
Operators waiting for instructions from supervisor.
Storage occurs when the object is kept in an authorised custody and is protected against unauthorised removal. For example, materials kept in stores to be distributed to various work.