Group Technology

What is Group Technology?

It is a manufacturing technique in which the similar parts are identified and grouped together to manufacture in one location for saving time and effort. So the similar parts are arranged into part families, where each part family possesses similar design and/or manufacturing characteristics.

A plant can be easily adapted to group technology when the plant currently uses traditional batch production and a process type layout.

For example, 

If a plant wants to manufacture 5000 different part numbers, we can group the vast majority of these parts into 20 to 30 distinct families by identifying the similar geometry and its manufacturing characteristics. Then the processing cycle time can be reduced by arranging the production equipment into machine groups or cells to facilitate workflow. Grouping the production equipment into machine cells where each cell specializes in the production of a part family is called Cellular Manufacturing.

Objectives of Group Technology

• Reduce Machine Lead Time
• Improve equipment utilization
• Reduce tooling
• Improve scheduling
• Achieve close tolerance

Steps to be taken by a company to implement Group Technology

Identifying the part families

If the plant wants to group the 5000 different parts into part families, they have to review all part drawings to find the similarities in its manufacturing process steps, the geometry shape, and size for grouping. So this task consumes a significant amount of time.

Rearranging production machines into the machine into machine cells

It is the time consuming and costly to implement and accomplish this changeover. So the company will take this step only when they have a clear roadmap for their production planning.

Part family examples

Figure 1

In figure 1, The two parts are identical in shape and size but have different manufacturing requirements.

(a) Quantity: 3000 parts/ year

      Material: AISI 1018 Steel

(b) Quantity: 7000 parts/ year

      Material: ASTM A216 WCC

                                       

Figure 2

Figure 2 shows the family of parts with similar manufacturing process requirements but different design attributes.

 The manufacturing process steps are,

• All parts are machined from cylindrical stock by turning.
• Some parts require drilling.
• Some parts require drilling and milling.

Benefits of Group Technology

• Standardization of tooling, fixtures, and workpiece setups.
• Parts move within machine cell rather than the entire factory.
• Material handling time is reduced.
• Process planning and production scheduling are simplified.
• Higher quality of work.
• Lower manufacturing lead times since the setup time is reduced.