Continuous Production System
Continuous production system involves a continuous or almost continuous physical flow of materials. It makes use of special purpose machines and produces standardized items in large quantities. The examples are petrochemical, cement, steel, sugar and fertilizer industries, etc.
In a Continuous Production System, the items are produced for the stocks and not for specific orders. Before planning manufacturing to stock, a sales forecast is made to estimate the likely demand of the product and a master schedule is prepared to adjust the sales forecast based on past orders and level of inventory. Here, the inputs are standardized and a standard set of processes and sequence of processes can be adopted. Due to this, routing and scheduling for the whole processes can be standardized.
After setting out a master production schedule, a detailed planning is carried out. Basic production information and bill of materials are recorded. Information for the machine load charts, equipment, personnel and material needs are tabulated. In continuous production, each production-run manufactures in lot sizes and the production process is carried out in a definite sequence of operations in a predetermined order. In process storage is not necessary, which in turn reduces material handling and transportation facilities. First-in-First-out method is followed in the system.
Characteristics of Continuous Production System
1. Standard products are manufactured, which have large demand throughout the year.
2. Standardized inputs and standardized sequence of operations, machine tools and equipment are used.
3. Division of labour is made more efficient.
4. Minimum and constant material handling.
5. Minimum flow of work at any point of time.
6. Small work in progress is involved.
7. Use of productivity techniques is feasible.
8. Minimum cost of production per unit is possible.
9. Rigid quality control is exercised.
10. More maintenance is required.
Types of Continuous Production
There are three types of continuous production viz., mass production, process production and assembly production.
1. Mass Production
In this type of continuous production, only one type of product or a maximum of two or three types are manufactured in large quantities, as much emphasis is not given to orders of the consumers. Standardization of product, process, materials, machine and uninterrupted flow of materials are the main characteristics of this system.
Mass production system is employed in several industries where the production is carried on without any interruption. Electronics, electrical, automobiles, bicycles and container industries are a few examples of mass production industries.
Mass production system offers economies of scale as the volume of output is large. Quality of products tends to be uniform and high due to standardization and mechanization. In a properly designed and equipped process; individual expertise plays a less prominent role. Of course, the exact quality level depends upon the quality control systems and management policy of the plant.
2. Process Production
This system is used for the manufacture of those items whose demand is continuous and high. Here, single raw material can be transformed into different kinds of products at different stages of the production process e.g., processing of crude oil in refinery — we get kerosene, gasoline, etc., at different stages of production. On the basis of the nature of production process, flow of production may be classified into
- Analytical process of production and
- Synthetic process of production.
Analytical Process of Production: In analytical process of production, a raw material is broken into different products. For example, crude oil is analyzed into gas, naphtha, petrol, etc. Similarly, coal is processed to obtain coke, coal, gas, coal-tar, etc.
Synthetic process of production: Synthetic process of production, on the other hand, involves the mixing of two or more materials to manufacture a product. For instance, lauric acid, myristic acid, plasmatic acid, stearic acid, linoleic acid, etc., are synthesized to manufacture soap.
3. Assembly Production
In assembling process, two or more components are combined to manufacture a finished product. Manufactured parts are joined into sub-assemblies or final assemblies. Such process is employed in assembling automobiles, radio sets, television sets, bicycles, watches, cameras, etc.
Assembly line is a type of flow production which was developed in the automobile industry in the U.S.A. A manufacturing unit prefers to develop and employ the assembly line because it helps to improve the efficiency of production. The use of flow production methods results in cost reduction. Assembly line is particularly useful when a limited variety of similar products is to be produced on a mass scale or in fairly large batches on a regular or continuous basis.
In any production system, the most vital decision is the proper layout of assembly line. The design of assembly line involves the proper balancing of technology and other manufacturing facilities so as to develop a rational approach for optimization of results. The assembly line design depends largely upon product design and location of production. In order to develop an assembly line, machines are positioned keeping the following considerations in view:
- the rate of flow of work
- the direction of manufacturing operations
- the inconvenience and comfort of operators or workers
- the availability of service facilities like water, electricity, compressed air, oxygen, etc.
- the supply and demand of materials.
In an assembly line, each machine must directly receive material from the previous machine and pass it on directly to the next machine. Therefore, the location of machines is automatically regulated by the sequence of operations.
Machines and equipment should be arranged in such a manner that every operator has a free and safe access to each machine. Space should be provided for free movement of fork lifts, trucks, etc., which deliver materials and collect the finished products. The passage should not be blocked and workers must not be in danger of being hit by the moving trollies, etc. At the same time, there should be commercial utilization of floor space.
Assembly line process is employed in assembling automobiles, radios, television sets, computers and other electrical and electronic products.
Advantages of Continuous Production System
1. Reduced Labour cost,
2. High accuracy,
3. Reduced material handling,
4. Simple control process,
5. Minimum wastage,
6. Better materials /inventory control,
7. Higher return on investments.
Disadvantages of Continuous Production System
1. Heavy loss during slack demand period
2. Rigid maintenance and upkeep of machines
3. Customers’ tastes cannot be met as only one standard product is manufactured.
4. Difficult to adjust to new situations and specifications.
5. Special purpose machine tools are required.
Suitability of Continuous Production System
Continuous system is best suited to organizations which intend to produce a limited variety of products on a large scale. The heavy fixed costs of specialized equipment that are utilized for operating at low cost per unit can be distributed over a high volume of output.
Continuous production system can be applied to those industries which satisfy the following requirements:
- Uniform demand,
- High volume of production,
- product standardization, and
- Process balancing.