• 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.