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Just in Time Manufacturing

Just in Time Manufacturing
Just in Time Manufacturing Concept JIT Philosophy: With the progression in product-process technologies and the hybrid manufacturing systems, the Japanese have been perfecting a manufacturing system called ‘Just in Time’ or ‘JIT’. This JIT operating system is nothing but a production strategy that strives to improve business return on investment by reducing in-process inventory and associated carrying costs. The JIT purchasing system has emphasis on timing to supply materials just in time for use on the factory floor. Equally important emphasis is given to close and long term relationship with a few suppliers. The suppliers in JIT manufacturing are geographically closely located. Specifications: Producing and delivering finished goods ‘just in time’ to be sold Partly finished goods ‘just in time’ to be assembled into finished goods Parts ‘just in time’ to go into partly finished goods Materials ‘just in time’ to be made into parts. Loose specifications instead of rigid product specifications are used which leads to best use of supplier specialization and expertise for low cost and better quality. Frequent deliveries (daily deliveries) of small lots of exact quantities required are supplied directly to the shop floor avoiding large inventories, paper work and double inspection. The JIT system underlines the mutual confidence between buyer and supplier and long term relationship. This leads to investment by the supplier for the benefit of the buyer in terms of plant and equipment for improvement of quality, reduction of cost and shortening manufacturing lead times. Where does the responsibility lie? ‘The responsibility for the quality rests with the manufacturer of the part’ is the principle behind this Japanese practice. The primary responsibility for quality is transferred from quality control department to the production department. The quality control is considered a line function rather than staff function. The processes are designed to have less specialization on the part of workers. The physical layout is arranged in such a way that workers can operate two or three machines effectively and thereby become multifunctional. Good Quality First Time Every Time: Workers are organized in small closely linked groups thereby building team work. The production for each stage is planned in small lot sizes just meeting the needs of the subsequent stage. The system is such that even if one item produced is substandard, it would affect subsequent processes causing shortages and exposing the process or worker who has produced substandard item. This acts as a great motivator to produce good quality first time, every time. This also heightens the awareness among the workers about the inter dependence of processes. Taiichi Ohno, Father of the Toyota Production System saw this as an attribute rather than a problem. He used an analogy of lowering the water level in a river to expose the rocks to explain how reducing inventory showed where production flow was disrupted. Once bottle necks were exposed, they could be rectified or removed. Since one of the main barriers was rework, lowering inventory shoved each shop to improve its own quality. Just-in-time is a means to improving performance of the system, not an end. The result of the Japanese manufacturing system is quite pervasive in the areas of: Reduction in inventory Reduction in scrap Reduction in work Reduction in indirect costs Reduction in spare Reduction in administrative costs Increase in motivation of workers Increase in quality Better response to customers Better system flexibility and quicker response. What is kanban? Kanban is Japanese for “visual signal” or “card.” Toyota line-workers used a Kanban (i.e., an actual card) to signal steps in their manufacturing process. The system’s highly visual nature allowed teams to communicate more easily on what work needed to be done and when. It...
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Design of an Ideal Plant Layout

Design of an Ideal Plant Layout
Design of an Ideal Plant Layout Approach to proper layout: When a new plant is erected, a good deal of expertise is used by management to design a proper layout. A comprehensive approach with regard to the placement of machineries, location of stores, inspection cabins, tool rooms, maintenance wings, receiving and shipping departments, toilets, canteens and other handling equipments, is necessary for achieving quick and smooth production at the least cost. There is no set pattern of layout for all plants. What is suitable for a giant plant will not be fit for a small factory. What goes well with a processing industry may not match a job industry. But, the basic principles governing a plant layout are more or less the same. Cost of Production: The all time concern of big industries is the ever rising cost of production. Their priority would be mass production or continuous production to factorise the economy of scale. This is possible where industries are involved in producing highly standardized products. Industries involved in the production of customized or specialized products, catering to premium customers, cannot go for mass production since it is not a feasible option. They have to dedicate separate lines of production for different products. Invariable of the type of production, all industries need to cut down their costs wherever possible. The only possible solution is to design a suitable layout that facilitates uniform and minimum movement of materials thus avoiding wastage, minimization of production delays and avoidance of bottlenecks. An ideally laid plant layout reduces manufacturing costs through reduced materials handling, reduced personnel and equipment requirements and reduced in-process inventory. It is amazing how industries in Japan have mastered the art of employing Just-in-time concept, which focuses on continuous improvement and increases the rate of return on investment by reducing the in-process inventory and associated costs. The importance of plant layout would be better appreciated if one understands the influence of an efficient layout on the manufacturing function. An efficient plant layout would definitely incorporate the following aspects: Economies in handling-cut down material handling costs that account for 30-40 percent of the manufacturing cost Effective use of available space-especially in urban areas, where every inch of available space is an asset. Minimization of production delays-on time delivery schedules and speedy execution will help. Improved quality control-to reach expected standards of production Minimum equipment investment-by planned machine balance and location Identification and rectification of bottlenecks-don’t allow materials to pile up at any place of production, don’t allow workers to be lethargic, keep the machines in the best of condition to speed up operations Better production control-facilitated by a planned layout Better supervision-a good plant layout enables the supervisor to have a hawks eye on the entire shop floor Improved utilization of labor-process flow should be planned in such a way that workers should be equipped all the time without any lull Improved employee morale-by providing better working conditions, employee facilities, increased earnings, reduced accidents etc. , Scope for Expansion: A good plant layout must also have scope for expansion or revision in future. Even best layouts become obsolete over a period of time, so revisions ranging from minor alterations to a complete dismantling of the existing structure and installation of a new layout become necessary from time to time. Manufacturers, who are keen to survive the global competition, must consider revising their layouts which should fall in line with technological and market...
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