Group Technology - 2

A Classification Scheme: GT classification addresses the structuring of part attributes into a set of clusters with similar features---GT coding.

Group technology coding – the process of assigning symbols, numerics, and letters to a particular attribute of a particular item. 3 different coding structures: monocodes, polycodes, hybrid (mixed-mode) codes

Traditional coding structures are useful for:
Identifying similar parts in manufacturing--- bar code system.

GT coding system using bar-code technology can:
improve accuracy and productivity in identifying similar purchased items and can also facilitate communication between the buyer and the vendor.

Example: Once all the purchased items are categorized on the basis of similarity and then bar coded by the buyer, it will be much easier and faster for the buyer to handle them because they can be scanned for sorting, order picking, cycle checking, warehousing space arrangement, printing of bills of lading, and so forth. Recognizing these numerous benefits, we propose the incorporation of traditional coding structures into the computer-based supplier bar-code system.

The design phase:
- new designs can be kept to a minimum
- shop floor workers and inspectors know the existing parts very well and also know which parts need more attention.
- Quality can be maintained at a high level

A manufacturing phase:
- The groupings of the parts can be done using geometric features and processing requirements
Geometric groupings can be done automatically with the innovative CAD systems to generate the geometric code for the newly designed part.

Processing based codes contain more useful and accurate information, but are more time consuming as well.

In the manufacturing phase, standardization of manufacturing processes reduces the amount of new molds significantly. Therefore, it reduces costs and shortens the period from design to market--- very important to maintain high quality production.

Implementations of the process- based approach:
- analyzing the flow of parts through the shop
- coding parts and then grouping them into families based on their manufacturing processes
- making machine group selections.
By, applying GT, a shop floor worker can be divided into several cells based on the machine groups. Since all the parts within a family will be manufactured through the same machine cells, it is possible for shop floor workers and inspectors to become familiar with a part family quickly. This is a key to producing high quality products because workers know these parts very well.

Managerial Benefits:
Reduced purchasing cost through volume purchasing. By identifying purchased materials serving the same function, GT enables the buyer to purchase fewer different items at higher volumes. Subsequently, the buyer can take advantage of substantial volume or shipping discounts.
Faster lead time. By computerizing the coding system, the buyer can quickly identify the materials or the parts needed. Thus, the buyer can speed up the ordering process, thereby reducing order cycle time.

Better negotiation leverage. On many occasions, the buyer repeatedly purchases similar items. Since the GT classification and coding system can be a basis for value analysis, the buyer can not only discover substantially less expensive items from other suppliers, but also estimate the supplier’s actual profit margins. This information can be used as a valuable bargaining tool for negotiating with the suppliers when the purchase of similar items recurs.

Potential Obstacles:
Management resistance to change. Since the introduction of an innovative GT concept requires new mind-set and training for the buyers, they may be unwilling to devote their and energy to GT applications in purchasing. That is to say, unless GT is introduced gradually to a purchasing department, the buyers may resist due to their tendency to rely on conventional wisdom rather than the unknown and unproven concept, namely GT.

Extensive data requirements. The proper identification of purchased items often dictates their accurate classification and coding with respect to design, engineering, and functional similarities. The proper identification, however, necessitates detailed item descriptions which can only be found in extensive purchase records and data.

High Start-up Cost. GT coding is almost impossible without the help of interactive computer graphics and automated information storage/retrieval systems because: (1) graphical images may better help the buyers recognize similarities in design and engineering specifications and (2) the long list of item characteristics such as geometry, shape, dimensions, tolerance, functions, and bills of materials cannot be readily available to the GT users without the aid of automated information storage and retrieval systems which usually incur high expenses until GT is in place.

Bibiliography:
Bourke, Richard and Kempfer, Lisa. “Achieving Success with Mass Customization: The Vital Contribution of Engineering.” Computer – Aided Engineering. (Oct 1999).

Ham, Inyoung, Katsundo, Hitomi and Teruhiko, Yoshida. Group Technology: Application to Production Management. Boston, MA: Hingham, 1985.