Facilities layout (plant layout)

Introduction

The term plant layout is used in broad sense to include factory layout and machine layout. A plant layout refers to the arrangement of machinery, equipments and other industrial facilities – such as receiving and shipping departments, tool rooms, maintenance rooms, employee amenities etc. for the purpose of achieving the quickest and smoothest production of the lest cost.

Meaning

Plant layout may be defined as physical arrangements of industrial facilities. This arrangement includes the space needed for material movements, storage, indirect labour and all other supporting activities or services as well as operating equipment and personnel. Plant layout basically:

• Placing the right equipment.
• Coupled with the right method.
• In the right place.
• To permit the processing of a product unit in the most effective manner, through the shortest possible distance, and in the shortest possible time.

Definition

According to K.G.LOCKYER, “the disposition of the various parts of a plant along with all the equipment used there in, is known as the plant layout, which should be designed to enable the plant to function most effectively”.

Needs for plant layout

• When a new plant is set up to manufacture newly designed products.
• When a new product line is introduced in the factory.
• When additional space is required to meet increased demand for products.
• When frequent accident occur in the factory.
• When the existing facilities are to be rearrangement due to change in methods or production.
• When the existing factory is shifted to a new area.
• When the cost reduction program is launched.
• When improvements are to be made by incorporating scientific and technological innovations.

Factors affecting the plant layout decision

1. Type of production: - the plant layout for engineering unit will be quite different from that of a flour factory.
2. Production system: - the plant layout is a continuous production system will be totally different that under the intermitted production system.
3. scale of production: - the plant layout and material handling equipment in the large scale organization will be different from that in the small-scale manufacturing activity.
4. Type of machine: - the use of simple-purpose and multipurpose machines substantially affect the plant layout. Similarly noisy and vibrating machines require special attention in the plant layout decision.
5. Type of building facility: - the plant layout in a single story building will be different from that in a multi-story building.
6. availability of total floor area: - the allocation of space for machines, work benches, etc is made on the basis of the available floor area. Use of overhead space is made in case of shortage of space.
7. possibility of future expansion:- the plant layout is made in the light of the future requirements and installation of additional facilities.
8. arrangement of material handling equipments: - the plant layout and the material handling services are closely related and the latter has a decisive effect on the arrangement of production process and plant services.

Types of layout

1. Process or functional layout
2. product or line layout
3. project or fix position

1. Process layout

The layout in which all the equipments performing similar tasks are grouped together is called the process layout.

It is also called the functional layout, as the material and machines required are grouped depending on their functions. For example: the milling machines, machines can be grouped together and the grinding machines can be grouped together.

Advantages

o A high degree of variety of products can be manufactured.

o Flexibility and adaptability to change is high.

o Machine breakdown do not cause of stoppage.

o It is easier to instill job satisfaction to workers.

o Coordination and supervision is simpler.

Disadvantages

o Higher flow time of the product due to zigzag flow through the system.

o Larger number of machine set-ups.

o Low machine utilization.

o More material handling.

2. Product or line layout: -

The layout in which the equipments are placed in the order in which they are used for producing the product is called the product layout. The product layout is also called the line layout, as the materials and machineries required are place in sequence. This type of layout is useful in automobiles industries or industries where assembling of materials and part take place. In such industries, you need to start the process by feeding in the raw materials and the process ends with the production of the final product. In the product layout, workmen are required in less number that automatically reduces the cost and leads to higher productivity, as the whole process is automatic.

Advantages

o Low total flow time for the product.

o High rate of output, because there are no interruptions to the flow.

o Simple production planning.

o Less inspection.

Disadvantages

o No variety is possible.

o No flexibility is regard to design changes.

o High capital cost and capital investment.

o Less job satisfaction for labour.

Difference between production layout and process layout

Combination of product and process layout

In practice, the adoption of a pure product layout or a pure process layout in rarely seen, as it is not possible to adopt either of these in isolation. So, we come across a combination of product and process layout which is widely practiced, especially in factories which are engaged in repetitive processes manufacturing standard products. This is on account of deriving the maximum benefits accruing from both product and process layouts, there by over coming the disadvantages of these layouts.

3. Project or fixed position layout

The layout in which the raw materials are placed in a fixed position is called the project layout. The project layout is also called the fixed position layouts, as the production operation is performed at one fixed position. This type of layout is useful when number of equipments is less. For example, aero plane and ship manufacturing industries use this type of layouts. In this type of layouts, the machineries are heavy and therefore, they are fixed at one position.

Advantages

o Reduces movement of machineries and equipments.

o Minimize damage or cost of moving.

o More continuity of the assigned work force since there is no movement of raw materials or product from one department to another. Hence, the problem or re-planning and instructing people each time a new type of activity is to begin.

Disadvantages

o Since the same workers are involved in more operations. Skilled and versatile workers are required. The necessary combination of skills may be difficult to find and high pay level may be necessary.

o Movement of people and material to and from the place may be expensive.

o Equipments utilization is low because the equipment may be left at a location where it will be needed again in a few days rather than moved to another location where it would be productive.

Advantages of plant layout

• Better work conditions for workmen.
• Minimization in material handling.
• Minimization in damage and spoilage materials.
• Minimization in congestion of materials, machinery and workmen.
• Flexibility in changing production conditions.