Cellular Manufacturing

Cellular manufacturing also known as Group Technology is an approach whereby production can be done in small batches while taking advantages of the flow characteristics of the product or line layout. Components that may appear to be dissimilar but which require similar manufacturing processes and/or similar setups of the machine are grouped together and go through a particular group of such machines which may be dissimilar. Thus, instead of functional work centers we have these groups of machines or short lines. For instance, we may have a turning machine, a drilling machine and polishing equipment put together in a group, using which a group of components can be manufactured. However, not all components of a components’ group need to go through all the machines in the corresponding group or short line of machines. This concept is called Group Technology. Each of these short lines or groups of machines is also called as a ‘cell’. A cell thus consists of a group of machines and a ‘family’ of related components being produced on these machines. Since the manufacturing plant would now consist of several cells, manufacturing using such Group Technology is also called Cellular Manufacturing.

Group technology exploits the similarities and relationships between large populations of components. It thereby could reduce transport between successive machines, reduce set up on a machine and cut down the artificial uncertainty of the flows. The effect would be a reduction in the time and cost of manufacture.

Cells can be formed to manufacture different variety (within a range) of components. The entire variety requirement of the factory in the short term and a foreseeable intermediate term can be met by having a limited number of such lines or cells. In effect, we have all the variety needed, and at the same time we have simulated line production too. We thus have the flexibility of variety as well as reduced flow times. A small number of people functions as a cohesive group and accomplishes a common whole task. So, there is a lot more job satisfaction. Unlike large assembly lines, there is no boredom here and very little in-process inventory is needed within a cell.

Management can empower the cell to function as an independent unit with independent maintenance and internal quality functions. The management has to ensure, however that the ‘group’ goals are in line with the company goals.

Benefits of cellular Manufacturing:

What happens with such grouping? We already saw some of the advantages. Here is a more comprehensive list.

1. Compared to the earlier process layout, there are very few halts. Hence flow times are reduced considerably.
2. Unnecessary fresh setups or modifications to setups are eliminated. This saves process times significantly.
3. “Very few halts” translates to a drastic reduction in inventories of work in process.
4. However all the required variety can be produced. Group technology does not compromise on the variety of items.
5. Even a sudden rush order can be produced without causing much problem.
6. Employees feel empowered.
7. Employees in the cells derive much job satisfaction.
8. Cells satisfy several other psychological needs of its members: a sense of belonging self esteem mad security. This, in turn, reduces absenteeism, labor turnover and labor unrest.
9. An employee of a cell is free to do any operation within the cell, provided he has developed that skill. Multi-skilling is commonly observed in cellular manufacturing. So, there is job enlargement for the employee.
10. Since the employee is familiar with a known range of components that come to a cell, the employee tends to make less errors; this can improve the quality of the items.
11. Quality can also improve because of reduced handling of the items, and multiple operations get done in a single cell.
12. Since cells mean a modular approach to organizing production, it is easier to manage/direct/reorient/repair a cell than either a huge elephantine flow or the amorphous process layout.
13. In time of crisis, such as sudden demand changes or labor unrest, the crisis can be contained because of the modular nature of production.
14. Production control methods could be simpler; there could even be visual methods of production control in some cases. Because, the product (being worked upon) goes quickly through the system.