Types of Manufacturing System PDF

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THIS IS EXPLAINS THE TYPES OF MANUFACTURING SYSTEM...

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Define FMS? A Flexible Manufacturing System(FMS) consists of group of programmable production machines interconnected by means of an automated material handling and storage system, and controlled by an integrated computer system to produce a variety of parts at non uniform production rates, batch sizes and quantities.

Types of Manufacturing System As it has been discussed earlier that there are a number of factors which are to be considered before commencement of manufacturing. These factors also lead to guide about the type of manufacturing system to be followed. Manufacturing system is of two types: A. Intermittent Manufacturing/Production System B. Continuous Manufacturing/Production System

Types of Production System Intermittent Production System (Production to Order)

Continuous Production System (Production to Stock)

Job Production

Mass Production

Batch Production

Process Production

A. Intermittent Manufacturing/Production System: Intermittent means something that starts and stops at irregular intervals. The system is named so because here, the flow of raw material is intermittent. This system of production is followed in those industries which manufacture goods to fulfill the orders of customers. Here the products produced are not stocked. It is a system where facilities are flexible enough to handle a wide variety of products because the production is done on the basis of orders placed by customers. In the industries where intermittent production system is followed the components are combined differently for different customers. The finished product is heterogeneous in nature but within a range of standardized options assembled by the producers.

Characteristics of Intermittent System i) ii) iii) iv) v)

It is suitable where the goods are to be produced in wide variety. The flow of goods is intermittent not continuous. The quantity to be produced is small. Single sequence of operations is not followed and the adjustments are made to suit different jobs or batches. Inventory of work-in-process is high.

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General purpose machines and equipments are use to manufacture variety of products. Workloads are generally unbalanced. Specialization of workers is general. Equipments are laid out by process.

Classification of Intermittent System Intermittent production system is of two types: a. Job Production b. Batch production Both of these types of production systems are explained as under. a. Job Production Job production involves the manufacturing of single complete unit by one operator or a group of operators. This is a ‘special order’ type of production where the goods are produced for definite customers. Each job or product is different from the other and no repetition is involved. The product is usually costly and non-standardized as it requires highly skilled labour and high investments. The demand of the product is not on a continuous basis so the production becomes intermittent. Some examples of job production are:  Dam construction  Power projects  Ship building. Characteristics The characteristics of job production system can be classified as under: i) The product manufactured is custom-made or non-standardized. ii) Whole project is taken as single operation. iii) High unit cost of production. iv) Volume of output is low. v) Variable path materials handling equipment are used. vi) High capital investment is required. vii) Versatile and highly skilled labour is required. viii) A wide range of general purpose machines like grinders, press, drilling, shaper etc. is used. Merits The merits of job production system can be classified as under: i) A fault in one operation does not stop the process. The other operations keep on running. ii) Due to its flexibility any change in production design can be easily adapted. iii) The machines are installed close to each other which results in less material handling. iv) As the machines are closer to each other the waiting period between operations is also reduced. v) It is cost effective and time-effective as there are operations in a group which are similar in nature. Demerits The demerits of job production system can be classified as under: i) To ensure a regular and smooth production a complex schedule of activities is required.

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Raw materials and work-in-progress inventories are high. It is the most complex system of production, for example, in building a ship thousands of individual parts must be fabricated and assembled. Workloads are unbalanced, speed of work is slow and unit costs are high.

b. Batch Production Batch production is another type of intermittent production system. Batch production occurs when many similar items are produced together. Each batch goes through one stage of the production process before moving onto next stage. Good examples include:  Cricket bat manufacture  Baking/meal preparation  Clothing production In this type of production system, production of an individual unit is not done; rather numbers of units are produced in batches. The new batch starts only after completion of previous batch. It is a combination of mass production and job production. Under this type of system machine manufactures different products at time intervals, and each product being produced for short time using mass production methods. Both job production and batch production are similar in nature, except that in batch production the quantity of product manufactured is comparatively large. In batch production system production planning is not based on sales forecasts but it is done according to promotion programs of the organization, past information and the general business conditions It is defined as “The manufacture of a product in small or large batches or lots at intervals in which a series of operations are performed, each operation being carried out on the whole batch before any subsequent operation is performed”. Characteristics The characteristics of batch production system can be classified as under: i) Low investment of capital is required. ii) Production Planning is not based on sales forecasts. iii) Production planning is based on promotion programs of organization and past information. iv) More specialized labour is required. v) The production is done for customers not for stock. Merits The merits of batch production system can be classified as under: i) Manufacturing in batches helps in reducing unit cost. ii) Care of specific customer needs can be taken.(e.g. size, weight, style). iii) Use of specialized machinery and skills help in increasing output and productivity. Demerits The demerits of batch production system can be classified as under:

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Time lost switching between batches and machinery may need to be reset. It is potentially de-motivating for staff.

Continuous Manufacturing/Production System “Continuous flow production situations are those where the facilities are standardized as to routings and flow since inputs are standardized. Therefore a standard set of processes and sequences of process can be adopted”. --Buffa Thus in continuous production system large quantities of a single product are produced with few variations following a standard set of processes and sequence. It is carried on continuously in expectation of demand. In this type of production system items are produced for stock and not for the specific orders of customers. It involves a regular movement of items throughout the production process. This means that when one task is finished the next task must start immediately. Therefore, the time taken on each task must be the same. This type of production system is associated with large quantities with high rate of demand. Continuous production involves the use of production lines such as in a car manufacturer where doors, engines, bonnets and wheels are added to a chassis as it moves along the assembly line. It is appropriate when firms are looking to produce a high volume of similar items. Some of the big brand names that have consistently high demand are most suitable for this type of production. Characteristics i) The volume of output is generally large and goods are produced in anticipation of demand. ii) The material should be as per the specifications and should be delivered on time. iii) The product design and the sequence of operations must be standardized i.e. identical products are produced. iv) There must be continuity in demand as the production is done in anticipation of demand. v) It is preferred when the demand for the product is high in volume. vi) Automatic machines are used to perform standardized operations. vii) Machine capacities are balanced in such a manner that materials are fed one end are received on the other end in form of finished products. viii) The sequence of operations is predetermined so material handling equipments have a fixed path. ix) Appropriate plant and equipment is required. x) Product layout designed according to a separate line for each product is considered. Merits i) The main advantage of continuous system is that the inventory of work-in-progress is minimum. ii) This type of production system offers high level of accuracy.

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The quality of output is kept uniform because through repetition of work each stage develops. Control of this type of production system is simple. Any delay at any stage is automatically detected. Since most of the work is done through machines which, in turn, reduces direct labour requirements. Handling of materials is reduced under this system of production. The materials are handled through conveyer belts, roller conveyers, pipe lines, overhead cranes etc. Any weakness in this system can be located easily. As the production is high the firms can enjoy benefits of economies of scale. Investment in materials is quickly transformed into income from sale.

Demerits i) It is a rigid system as a fault in one operation disturbs the entire process of production. ii) The investment in this type of production system is fairly high. iii) Standby equipments to meet the breakdown are essential. iv) It is very difficult to alter the production process. v) Conducting the same work a number of times becomes boring for the employees. vi) All products are similar and cannot be tailored to individual tastes.

Classification of Continuous System Continuous system can be divided into two types: a. Mass Production b. Process production Both these types of production system can be explained as under. a. Mass production It is also known as ‘Flow Production System’. This system is used where large quantities of goods are produced and no emphasis is paid on customer order. The production is done to stock not to order. Standardization is the fundamental characteristic of this system. Materials and machines are standardized and a regular flow of material is maintained through predetermined sequence of operations. This type of production system is found in the industries engaged in manufacturing subassemblies or components. These parts are further assembled together and final product is produced. The industries observing this system reap the benefits of economies of scale as the volume of output is large. The example of mass production system can be the components of industrial products. b. Process Production This system is an extended form of mass production system. Here the production is carried out on automatic and highly sophisticated machines continuously through a uniform predetermined sequence of operations. It is employed in industries where bulk processing of material is required. In such a system, generally, single raw material can be converted into various products at different stages of production process for example crude oil is converted

in kerosene oil, diesel, petrol, LPG, etc at various stages. Other examples of this type of production system are:  Petroleum Industry  Cement Industry  Sugar Industry  Plastic Industry, etc. This type of production system is not labour intensive as maximum work is conducted on automatic machines and the worker is just an operator to monitor the machine and take corrective action, if required. Production volume is large and those items are manufactured whose demand is continuous and high. Generally in this system of production finished product of one process is used as raw material in the other process till the last process is completed. Continuous production may further be classified into two:  Analytical Process of Production  Synthetic Process of Production In Analytical Process of production, a raw material is broken into different products e.g. crude oil is converted into gas, diesel, petrol etc. Similarly, coal is processed to obtain coke, coal gas, coal tar etc. In Synthetic Process of production two or more materials are mixed to manufacture a product, for example, lauric acid, stearic acidare synthesised to manufacture soap....