3.1 OVERVIEW

• Most product models use an exact definition of geometry, or other details

 

• It can be useful to have a more abstract representation of a part for some tasks,

- Storage and recall of designs

- Recall of process plans for similar parts

- Classification of designs for analysis of production

 

• GT is used to identify subsets or families of similar parts for the purpose of realizing common features for improved design and process efficiency through standardization.

 

• GT codes can be used to represent products using any combination of geometry, manufacturing processes, and/or function.

 

• The advantages of such a system can be found in,

1. Product design - Group technology allows similar designs to be recalled on the computer. Instead of starting from scratch again.

2. Tooling and setups - standard tooling can be developed for a part family, and then standard setup procedures and times can be used.

3. Materials Handling - Factory floor layout can be updated to reflect part families, and reduce part handling time.

4. Production and Inventory Control - The use of GT to set up standard production techniques allows faster production, therefore less inventory, and Work in Process (WIP).

5. Employee Satisfaction - Grouping of machines allows easier tracking of quality (and achievement).

6. Process Planning - Standard plans can be developed for GT part families. The plans can then be altered to fit, instead of producing a new process plan.

 

• Problems with GT systems are,

1. Not suited to a factory with widely varying products

2. Can have a long setup time, and debugging

3. There are no standard GT codes developed - each GT code application will probably be unique.

4. A GT code may be hard for inexperienced users to read.

 

 

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