Plant layout and its types

Answer 1

The following are the popular types of plant layout:

(1) Process layout (2) Product layout (3) Combined layout (4) Static product layout or Project layout (5) Cellular layout (6) Job Shop layout. Each layout is explained in brief in the following paragraphs:

Process layout: It is also called functional layout. All machines performing similar type of operations are grouped at one location in the process layout e.g. all lathes, milling machines, cutting machines etc in the engineering shop will be clustered in their like groups. Thus all forging will be done in one area and all the lathes will be placed in another area. In this layout, several products may share a machine to make its full use. The sequential arrangement of the machine group is generally, but not necessarily made on the basis of labor operations. In this type of layout the process rather than the product has a dominating role. The product is given secondary consideration and is moved for the purpose of operations to the process section with like machines stationed at a particular point. This type of process is more suitable to job order type of production. In such production the operation differs from product to product. So, it is desirable to arrange the machines on the basis of process rather than on the products.

The typical arrangement of the machines in the process layout will be as under:

Product 'A' and Product 'B' with their differential sequence will be routed for the processing in the manner.

Advantages: The process layout avails of the following advantages:

1) Like product layout it eliminates the duplication of machines an enables the optimum use of installed capacity.

2) It facilitates the flexibility in production. It is more flexible than a line layout. Different products can be made without the changes in the arrangement of machine. The production capacity is not arranged in rigid sequence and fixed rated capacity with line balancing.

3) Like product layout, the break down of one machine does not interrupt the entire production flow.

4) Specialization in supervision becomes possible.

5) Individual incentive schemes can be developed.

Disadvantages: The following are the main disadvantages of the process layout:

1) Due to lack of straight line sequence of production, it is impossible to maintain the line balancing in production. So the problems of bottleneck and waiting and idle capacity arise.

2) The cost of material handling increases due to long routing and back tracking between the processes.

3) The processing time is prolonged which reduces the inventory turnover and increase the investments in inventories.

4) The inspection cost increases. Due to frequent changes in the machine set-up inspection is required at each stage of the process.

5) The cost of supervision increase due to specialist supervisors and more number of supervisors are required at each process unit.

6) The production planning and control becomes difficult due to complexities arising in routing, scheduling, dispatching and follow up.

7) It is not possible to implement the group inventive schemes on the basis of quantity of the products manufacturing

8) More space is required for internal storing, reservoir of materials and provision for the expansion of the particular process section.

Product layout:

In this type of layout, the machines are arranged in the sequence as required by the particular product. All machines as required to balance the particular product the product line layout. In this layout, one product goes through all the machines lined up, in the order required by its manufacture. The best known example of this type of layout is seen in motor car production. To make this layout successful, the work load on the various machines must be balanced. The process of getting even loading at each stage of production is called line balancing.

In this type of layout, the product is dominating over the process, in the sense that the product is given the primary importance and the process machine must remain present at a point where the product needs its services. Thus, unlike the process layout, the process is given secondary importance in relation to the product. Product layout suitable for continuous flow production with few items of production:

It does not require frequent changes in machine set up. The typical arrangement of the machines in the product with the separate independent product lines for the Product 'A' and Product 'B' will be as shown.

Advantages: The product layout is advantageous as under:

1) Reduced material handling cost due to straight line production flow.

2) Mechanization of material handling is possible due to handling between fixed points.

3) Line balancing may eliminate bottlenecks an idle capacity.

4) Shorter operating cycle due to shorter and speedier movement of materials.

5) Maximum utilization of machine and labor capacity through developing proper balance between them.

6) Effective control over production with reduced supervision by generalist supervisors. By reducing the manufacturing to simple steps we can often use less skilled labor.

7) Effective quality control with reduced inspection points. It does not require frequent changes in machine set-up.

8) Effective production planning and control. Unlike process layout, the routing, scheduling, dispatching and follow up are relatively easier.

9) Maximum use of space due to straight production flow and reduced need of interim storing.

10) It facilitates the implementation of the group inventive schemes for the workers.

11) It is relatively easy to control