It may be defined as a technique of locating machines, processes and plant services within the factory so as to achieve the right quantity and quality of output at the lowest possible cost of manufacturing. It involves a judicious arrangement of production facilities so that workflow is direct. Principles regarding the plant layout A scientific criterion for determining a good Plant Layout: 1. Integration: Integration of men, money, materials and machines and support services in order to get the optimum output of resources. 2. Cubic space utilization:
Utilization of both horizontal and vertical spaces and height is very important to use the space as much as possible. 3. Minimum distance: Minimum travel of men and material should be implemented means; the total distance travel by the men and material should be minimized as much as possible. Further straight line movements should be promoted. 3. Floor: Arranging the floor to move the material/finished products in forward direction towards the final stage. 4. Maximizing coordination: Entry into and disposal from any department should be in such manner that it s most convenient to the issuing or receiving departments. The layout should be consider as a whole. 5. Minimum flexibility: The layout should be able to modify when necessary. 6. Maximum accessibility: All servicing and maintenance points should be readily accessible. For example; equipment should not be placed against a wall because necessary servicing or maintenance cannot be carried out easily. Further; equipments or other necessary units keep in front of a fuse box will impede the work of the electrician. 7. Safety security:
Plant Layout Essay Example
Due consideration to industrial safety methods is necessary. Care must be taken not only of the persons operating the equipment, but also of the passes-by, who may be required to go behind equipment as the back of which may be unsafe. 8. Minimum handling: Reduce the material handling to the minimum. Material being worked on should be kept at working height and never have to be placed on the floor if it is to be lifted later. The following principles also can be taken in to account when planning for a good plant layout; •The geographical limitations of the site; Interaction with existing or planned facilities on site such as existing roadways, drainage and utilities routings; •Interaction with other plants on site; •The need for plant operability and maintainability; •The need to locate hazardous materials facilities as far as possible from site boundaries and people living in the local neighborhood; •The need to prevent confinement where release of flammable substances may occur; •The need to provide access for emergency services; The need to provide emergency escape routes for on-site personnel; •The need to provide acceptable working conditions for operators. PLANT LAYOUT TOOLS AND TECHNIQUES Procedure to identify the necessity of revising existing layout A scientific layout study is a disciplined objective procedure that clearly determines the goals to be attained, collects all relevant facts, thoroughly analyses the data and achieves an improved layout. The following are the steps in studying the feasibility of revising a layout. (i) Objectives of the investigation are to be formulated. ii) Collect the layout drawings of existing plant. (iii) analyze the information available on present layout with the help of flow diagram, process charts, analysis of service activities etc. (iv) develop a new plan of layout by means of improved flow diagram, process charts and final drawing of revised layout. Factors responsible for inefficient layout can be Factors responsible for inefficient layout can be : (i) layout planning is entrusted to unqualified/incompetent persons. (ii) various departmental heads are given the responsibility of planning the layout.
This leads to unhealthy competition for location and floor space and irrational emphasis on some plant activities. In the absence of any centralized control over layout department makes whatever revisions it fells are necessary with the result that plant operation as a whole suffers form high production costs. (iii) The site selected for the plant may impose restriction on the choice of good layout. Poor site can be characterized by poor rail and road connection, inadequate or no outdoor storage space and no prospect of low cost plant expansion. iv) the choice of unsuitable building may result in high production costs e. g the need of multi-story building may not have been recognized initially. (v) existing layout may not have provisions for future plant expansion. (vi) ineffective sales forecasting and production planning activiti9es may adversely affect an efficient plant layout. (vii) highly specialized plant facilities in a layout imposes limitations of the products the firm can offer in the market. (viii) poor preventive maintenance results in machine breakdown on interruption in production, which further leads to wasteful plant layout revisions.
Revising and improving plant Layout To maintain operating efficiently over a period of time, the existing plant layout must ordinarily be modified and improved continuously. There reasons are: (i) Increase in demand of the product may need expansion of manufacturing facilities. Expansion of plant may be due to (a) Output of new products in search of profit prospects e. g manufacture of electronic items, food industry, automobiles etc. periodically revise their existing models & styles. b) the horizontally integrated programme can expand only within the field of one main category of products whereas vertically integrated product program can expand to produce as many different products. (c) Plant expansion can be done to produce by-products. A by-product is a commodity the production of which i facilitated by the production of the main line of products e. g chemical products or waste material is considered a potential starting point for a new product gained form the distillation of coal. In industry every end product e. g firms manufacturing leather goods can use waste leather pieces to produce washers,shoe soles etc.
Similarly glass waste can be used in and papers. (d) Sometimes there may be excess plant capacity which results in increased production costs. The unused capacity can be used to manufacture new products. This may need some revision of the facilities and layout. (ii) To acquire more plant efficiency by using new technology: the use of advance technology in manufacturing systems may be characterized by increased mechanization, using modern sources of fuel and energy; new development sin process, materials, product design and scientific management . a) increased mechanization implies substitution of machine process for manual process, large capacity machines for smaller ones, and complex mechanical devices for simpler ones. Greater output at lower costs can be achieved by reduction in amount and king of labour required to produce goods. This may be done by elimination of one or more hand operations, increase in speed of machines, etc. (b) fuel and energy development: Technological progress can be seen through the use of new and improved forms of power e. g mechanical system of belts, shafts and pulleys is being rapidly by direct electric drive motor. c ) developments in process, material etc. can be judged form the use of automatic chemical process, increased efficiency in use of raw material by producing by products, product design may be improved for reduction in cost of production or attaining greater product simplification. Economy is attained by reducing unnecessary variety in the products. (iii) improving the layout through analysis and work simplification: A progressive management is always on look or improvement in plant facilities to save it from obsolescence. The evils of poor layout are usually concealed” hidden costs”.
There may be unnecessary handling, waste motions, delay in storage and other hidden expenses. Factors relevant in the choice of the Layout There some various factors relevant in the choice of the layout 1)Climatic conditions of factors relevant in the choice of the layout 2)Location of the Plant of factors relevant in the choice of the layout 3)Nature of Manufacturing System of factors relevant in the choice of the layout 4)Size of Output of factors relevant in the choice of the layout 5)Nature of the product of factors relevant in the choice of the layout Features of a good Layout
The layout of plant can be planned in a number of ways but a good layout should possess some basic characteristics, namely: (i) There should be sufficient space for the workers as well as for the equipment to perform their functions. This will ensure smooth and continuous flow of production process. (ii) Must provide adequate safety and security to workers against accidents or injury e. g. Provision of firefighting equipment, first-aid boxes etc. (iii) Sufficient gang-way space for materials, workers and semi-finished goods. This leads to increase in efficiency. iv) Arrangement of machines and equipment should be such that minimum material handling’s necessary for low cost processing. (v) Stores for in-process material should be provided at some convenient place i. e. not far from the place of operations. (vi) Supervision, co-ordination and control of the activity should be effectively and easily executed. (vii) There should be sufficient scope for making adjustments and modifications whenever any need arises i. e. the layout should be flexible. Typical weakness in a poor plant layout
The following characteristics are indicative of weaknesses in any layout plan: (i) low production density and under utilization of plant capacity. (ii) lack of flexibility in the plant production facilities. (iii) long processing time due to too many delays, temporary storage, bottle-necks etc. (vi) improper utilization of plant site including inaccessibility to the rail road siding, wasted outdoor area etc. (v) Over-specialization of production facilities. (vi) Improper location and ineffective integration of parts fabrication and subassembly feeder lines with the final assembly lines. vii) Uneconomical material handling. Lack of gravity handling and channelized flow of work. (viii) Costly inspection and difficulty in maintaining quality standards. (ix) Inadequate storage facilities. (x) Equipment and production machinery not accessible for maintenance and repair due to layout. (xi) Poor lighting, ventilation, air cleaning arrangement is in the layout. (xii) Inadequate safety provisions for workers. Steps in planning the layout for a new enterprise There are some various steps of planning i) The first thing is planning a layout is to study the objectives, production plan and the nature of machines, equipment and manufacturing operations involved in the production process. Select the equipment on the basis of product design and volume of the output to be attained. In other words the layout of the plant should be functional in the production of a specified product at the required rate of output. (ii) Accumulate layout data: machine data cards, machine load charts and templates of equipment. (iii) On the basis of information collected in step (ii) develop process charts which are vital in the development of a sound layout.
These charts summaries the production activities that are required to achieve the manufacturing objectives. (iv) Develop an over-all flow plan of operations for efficient processing and materials handling. The best flow of work both horizontal and vertical and the integration of operations form the receipt of the raw materials to storage of finished goods are the objectives to be attained. Process charts. Machine load data, production rate desired etc. should be considered in drafting the plan. (v) The sequence of mechanical operations is studied to fix the position of respective machines performing desired operations. vi) Select best suited type of building and develop a tentative plot plan for the site. The exact specifications of the building are designated only after the layout is developed in considerable detail. (vii) Layout templates or models of individual production machines and space for service activities: materials handling, receiving and shipping, inspection, storage, maintenance, offices etc. according to flow plan operations. (viii) Decision about the location of services facilities like cafeteria, toilets etc.
Inside the plant building is taken, keeping into consideration the requirements of the produciton process and comforts of the workers. (ix) The position of windows, ventilators, electric fittings, drainage of the layout are drawn and the production run is tested. (x) After analyzing all the details in steps (i) to (vii), drawings of the layout are drawings of the layout are drawn and the production run is tested. (xi) Modifications can be done according to the experience of test runs. Model of a layout The model of a layout can be made by studying the operations involved in the production process. i) Key operations are located. (ii) Locate main and minor gangways. These should be preferred near the walls and not across the floor. (iii) Locate the subsidiary equipments viz. rubbish bins, telephones etc. In a good layout packing department should be near to dispatching point whereas inspection place should be located near the windows for proper daylight. In addition to this the following specific points should be kept in mind for the layout of machines: (i) space occupied by a machine must include some overhang space for the travel of any part or for the movement of material. ii) Gangways must be adequate for the collection and delivery of material. (iii) Floor must be strong enough not only to carry the machine load but also to bear the load of semi-finished and finished goods. (iv)Servicing facilities and safety devices must be easily accessible. (v) Sufficient space around the machine must be provided so that operator can move freely to do his work. It should be observed that he layout of an organization has an impact on other functional areas. There is a strange integration between layout planning and other decision areas such as work measurement and method study.