Lean Manufacture, Just-In-Time Approach, Total Quality Management, and Total Productive Maintenance - Assignment Example

PART A: Economics, Quality, and Organization LEAN MANUFACTURE, JUST-IN-TIME APPROACH, TOTAL QUALITY MANAGEMENT AND TOTAL PRODUCTIVE MAINTENANCE Just-In-Time (JIT) manufacturing has been implemented successfully in Japan for the past 20 years. It is a philosophy as well as a technique that guides a manufacturing company in organizing and managing its business more effectively, and in planning and controlling its operations more efficiently. It is a way to achieve high velocity manufacturing. High Velocity Manufacturing Traditionally, a manufacturing business competes on price, quality, variety, after service, etc. Now, these conditions are merely prerequisites. Few businesses exist today without offering low prices, high quality, and good service. The key competitive factor has become speed. All else being equal, the faster a business responds to its customers, the more profitable it is. The shorter the lead-time in which a manufacturer can supply its products, the higher the probability that it will survive. High velocity manufacturing is a common goal for all manufacturing businesses. In high velocity manufacturing, everything is moving. Machines, people, funds and materials are constantly moving. Therefore, inventories in storage or on the shop floor are moving inventories rather than sitting inventories. Inventories are stocked only for a very short time, and will move to other locations only moments after being stocked. The conditions of high velocity manufacturing include flow manufacturing, line balancing, level schedule, and linearity. As we have mentioned before, JIT improves the manufacturing system gradually rather than drastically, as in business process reengineering (BPR). This gradual continuous improvement is defined by APICS Dictionary as “one less at a time”: a process of gradually reducing the lot size of the number of items in the manufacturing pipeline to expose, prioritize, and eliminate waste. “One less at a Just-In-Time Manufacturing time” is a constant, step-by-step methodology for making JIT work in any manufacturing environment. JIT is a never-ending series of small, controlled steps, not one great leap forward. In the JIT philosophy, not the same product is produced over and over again; instead, the same process is used repeatedly to produce different products. The procedure of “one less at a time” is as follows: 1. If the inventory is equal to zero then stop, else 2. Select the most prioritized process to be improved. 3. Improve the process. 4. Is the process economical? If no, go to step 3. 5. Reduce the inventory by a small amount. 6. Go to step 1. The third step “Improve the process” in the above procedure can be broken down into following steps: 1. Observe the existing method and collect related data on the selected process. 2. Investigate and analyze the data to generate alternatives to improve the process. 3. Evaluate the alternatives to determine the new method for the process. 4. Install the new method and educate the operator. 5. Maintain the new method. Reducing inventory forces the setup times to decrease for more frequently the products have to be produced to maintain lower inventory level. In order to have shorter setup times, processes must be designed to be more flexible and workers must be trained to do multiple jobs. The need for shorter setup times also demands that the number of items be fewer. The number of items can be reduced through a design of more common parts and modules in different products. Shorter setup times lead to smaller lot sizes and shorter lead times. Shorter lead times result in more frequent product delivery and decrease the need for accurate forecasting and planning which increase the schedule stability. More frequent distribution forces people to reduce paper work and material move distance, and to develop more efficient material handling and transportation systems. Less inventory demands a higher quality level, zero defect process, and better preventive maintenance. Less inventory also requires better communication between departments, customers, and suppliers, and hence requires a smaller number of suppliers. One inventory Less setup time lot size lead time production distribution frequency planning accuracy forecast accuracy schedule stability flexibility of process & personnel paper work material handling move distance transportation cost quality of product & process quantity of part numbers links to other dept. links to suppliers links to customers number of suppliers preventive maintenance Effects of fewer Inventories  Problems as opportunities JIT philosophy sees the problems as the opportunities. A problem is an opportunity to improve. JIT exposes problems rather than covering them.  Quality at the source Defects may occur at the design stage, any workstation in the production line, or the suppliers’ plants. Quality does not come from inspection. It does not come from manufacturing either. Quality comes from good design. The quality of a product is determined at the design stage, including product design and process design. A poor design will never result in good quality. In a production line, it is not adequate to inspect the products at the end the line. Inspections should be executed by the operators themselves at each step of the line before the parts are passed on to the following process. The operator in the next workstation has no obligation to inspect an incoming part. A defect must be screened out immediately after it occurs. For purchased parts, the inspection should be completed before delivery. Incoming inspection is not required.  Simplification Simplicity is a key to successful manufacturing. Products should be designed to be easy to manufacture, install, and repair. Only 2 or 3 levels should exist in the bill of material. Suppliers deliver the materials regularly and purchase orders are not required. Materials are stored at the point of use (POU), and picking orders are not required. Work centers produce the items when they are consumed and shop orders are not required. Material inventory records are not updated until the finished goods are reported complete. Simplifying the system is central to the philosophy of JIT.  Visual Control Visible control tools are used wherever possible. Cards attached to the materials, containers at sight, tags in stock indicating order points, etc. are examples of visual control tools. These signals are processed by human intelligence at the speed of light, and are superior to any computer in the world. JIT philosophy reminds us that natural human senses are effective tools but are frequently ignored.  Focus on Customer Needs In JIT philosophy, only values in customers’ eyes are real values. Values perceived by engineers but not accepted by customers are wastes. All activities from production design, material procurement, fabrication, assembly, distribution to after service, focus on customer needs. Any motion of the operator on the shop floor not adding value to customer needs is a waste.  Production to Customer Demand In JIT philosophy, only immediate customer demands are produced. Extra items not required immediately by the customers are not put into production. Without customer demand, there should be no production.  Respect for Individual Each individual in a company is an important asset. Education and training are frequently conducted to enhance the capability of the employees. Employee involvement and empowerment are part of JIT philosophies. Employee involvement is the concept of using the experience, creativity, and intelligence of all employees by treating them with respect, keeping them informed, and including them and their ideas in decision making processes (Apics, 1995). Employee empowerment is the practice of giving non-managerial employees the responsibility and power to make decisions that can effect their jobs or tasks. It allows employee to take responsibility for tasks normally associated with staff specialists, such as scheduling, inspection, etc. (Apics, 1995). JIT as an Environment In addition to philosophical concepts, JIT also provides an environment in which products are manufactured in a simpler way.  Repetitive Manufacturing Repetitive manufacturing is the production of discrete items in a production line with fixed routings. The items can be a product or a family of products. The product is standard or made from standard modules. The manufacturing environment is make-to-order (MTO) or assemble-to-order (ATO). The production line consists of workstations located close together and in sequence. Materials flow from a workstation to the next at a relatively constant rate. Material handling systems are normally used to move the materials from process to process in the production line. Normally, the capacity of the production line is kept sufficient. The repetitive manufacturing is based on an uninterrupted flow of materials.  Total Quality Management (TQM) Total quality management is a management approach used to achieve quality improvement and long-term success through customer satisfaction. TQM involves all members of the organization, and is meant to improve the quality of all processes, products, services, operations, and corporate culture. TQM activities follow a plan-do-check-action (PDCA) cycle to improve the quality. In the “plan” step, the problem is defined, the symptoms are explained, and the key performance measures are determined. In the “do” step, the cause of the symptoms is identified. The causes of the causes are also investigated until the root cause is uncovered. Then, an approach to solve the problem is developed and implemented. The performance measures can be changed in this step. In the “check” step, the effectiveness of the proposed approach is observed by using the performance measures. In the “action” step, the results are studied to determine what was learned and what can be predicted. The improvement process is standardized to apply to similar problems. In the PDCA cycle, the steps are not necessarily followed strictly sequentially. For example, if we find a proposed approach is not affirmative in “check” step, we may jump to the “do” stage to revise the approach.  Total Productive Maintenance (TPM) “Preventive maintenance” is a restrictive term which mentally prohibits us from thinking more broadly. TPM means preventive maintenance and continuing efforts to adapt, modify, and refine equipment in order to increase flexibility, reduce material handling, and promote continuous flows. It is operator-oriented maintenance involving all qualified employees in all maintenance activities. (Apics, 1995)  Total Employee Involvement (TEI) Elimination of waste and continuous improvement are the central ideas of the JIT philosophy. They can be accomplished only when employees are cooperative. A successful JIT environment should have the cooperation and involvement of everyone in the organization. Traditionally, operators take orders from management and do what they are asked to do, while management is in charge of planning, supervising, inspecting, etc. In a JIT environment, operators take responsibility for controlling the equipment, inspecting for quality, correcting the deviations, maintaining the machines, and improving the processes. Many of the tasks traditionally done by the management become the duties of the line workers under 8-12 JIT. Managers are not playing the game; they are coaches and the line workers are the players. The mission of a coach is to train the players.  Supplier Partnership In order to establish a smooth flow of materials into the factory, a close and reliable relationship with the suppliers is very important. Supplier partnership is the establishment of a working relationship with a supplier whereby the two organizations act as one. Relationships with the suppliers should be based on mutual trust, cooperation, and long-term commitment. JIT as a Control Technique In daily operations, JIT provides useful control methods. The characteristics of a JIT control technique include uniform loading, repetitive processes, pull system, using production cards, and synchronized production.  Pull System JIT control pulls materials from the previous workstation. The workstation replenishes any materials consumed by its following workstation. Since only the consumed materials are produced, the inventories between workstations never accumulate. For the first workstation of the factory, the supplier is its preceding workstation. For the last workstation in a factory, the customer is its following workstation. Customers pull the products from the factory, and factory pulls the materials from the suppliers.  Uniform Loading The loads for jobs in every workstation are equal. This makes the pull system possible. If uneven loading exists, the following workstation may have to wait for the materials from the preceding workstation. Uniform loading allows the materials to flow through the production line smoothly. Every workstation runs at a constant rate. If the demand increases, the production rates in all workstation increase together. If the demand drops, all workstations may have the same level of idleness. Just-In-Time Manufacturing 8-13  Production Card JIT control uses various cards to transmit production signals. During the production, these cards are attached to and detached from the materials. Production signals are transmitted from the following workstation back to the preceding workstation. The cards have various shapes and colors to indicate different purposes. Sometimes material containers or the material itself are themselves the signals.  Synchronized Production Synchronized production is a manufacturing practice in which production activities in each workstation are synchronized with certain control signals. The production rates of workstations are related to each other, and the work-in-process inventories are limited to a predetermined level. Synchronized production can be seen in JIT environments or theory-of-constraints (TOC) environments. The control signals are carried by kanbans in a JIT environment. In the TOC environment, drum-buffer-rope (DBR) is used to synchronize the workstations. Synchronized production will be discussed in the next chapter. PART B: B1 MACHINE A GRAPH OF COST AGAINST NUMBER OF ITEMS 1 MACHINE B GRAPH OF COST AGAINST NUMBER OF ITEMS 2 Machine B is better to buy because the payback period being infinitely long, B will repay the investment and then some. The graph of A cuts the x-axis at a smaller value than B. B2. Each component needs pounds 2.027. batch average range 1 25.0 3 2 25.03 3 3 25.14 3 4 25.35 3 5 25.4 3 6 25.46 3 7 25.58 4 8 25.63 4 period is 11.33 years. Machine B (b) B4 (b) B4(c) There is great discrepancy between the batches. However, there is convergence because the range does not differ much. B5. The cost of the new project is Pounds 2,000,000.549. Read More