Stapler free essay sample

Design efficiency = (number of functional component / total ) x 100 Major component: superstructure x2, loading component, pin holder, flexor, spring, pin No. functional component = 6 Total no. component = 9 Design effictencr (6/9)x100 = 66. 67% i) Suitability A breakdown of how the unit is currently manufactured and associated costs a) Sequence of assembly: 1 . Flexor + top superstructure + PVC holder 2. Bottom superstructure + PVC holder 3. Loading compartment + Pin holder + Spring 4. step 1 + step 2+ step 3+ Pin b) Assembly process 1 . The assembly process for the bottom and top superstructure is almost similar which they used hot stamping machine to assemble the PVC holder to the superstructure. The hot stamping machine use pressure and heat to imprint the PVC holder to fit on the superstructure. 2. To assemble the loading compartment, pin holder and spring, manpower is used. 3. After the above is done, the stapler is to be assembled to be one which c) Labour cost a pin is tlxed Example: production: 1 million unit of stapler per month 3 shift time taken to assembly 1 unit 0 2 minutes RM1500 per month per worker 26 working days 3 shift (20 hours) 1 person per shift = 6. We will write a custom essay sample on Stapler or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page 67 hours = 400. 2 minutes 2 minutes per unit, 1 shift = 200 units 3 shift 0 600 units/day 26 days 0 15600 unit/worker 1 million units = (1 workers Labour cost = (64 X RM1500)/ 1 million = RMO. 096/unit = RMO. 0/unit To reduce the labour cost, the assembly time per unit needs to be reduced. The assembly time per unit can be reduced to 1. 5 minute. To reduce the time, one of the sequences of the assembly process need to be reduced and hence the number of parts of the stapler need to be reduced. Therefore, with the time reduce to 1. 5 minute, the labour cost per unit is reduced to RMO. 75. d) Identify human error For the hot stamping machine, the time set by human might not be accurate which the time taken to applied on the product might be too fast. If the time is too long it might melt the product For the assembly part where human effort is needed, which is the assembly of the spring, the direction of hook might be opposite or the spring is not placed properly that the spring will be easily off. e) For the stamping process, there is stamping machine with combination process. While to hook the spring to the load compartment, human is needed. Finally the last process which is to gather the parts to one, human will put in a pin into the parts. ) Conclusion The assembly process of the design can still be simplified. Some process can be improved by using machine. The parts of the stapler can be simplified. (iii) Manutacturing process a) Parts of stapler: Top superstructure, bottom superstructure, spring, flexor, PVC holder, loading compartment, pin holder, pin b) Superstructure: This part is manufactured using stamping machine. Flat sheet metal material are laced between punch and die. When the punch pushes the material, the shape o f the punch will shear from the sheet. This process is a very cost-efficient way of mass production stampings because it does not require manpower to hold the material. Spring formation: Coil springs are wound around rods and heat-treated, to be pulled apart and pressed together, and still return to its original wound up condition. Flexor: A thin piece of steel is cut into the shape wanted is rolled or bent to its proper shape. To produce changes in the metals characteristics which gives the flexor more lasticity, the flexor is heated to a temperature which will cause internal stresses. PVC Holder: The pvc holders are made by injecting liquified plastic into a die, which is injection molding. The liquid flows into the open void and is then cooled, the shape of PVC holder is formed. Loading compartment pin holder: These parts are manufactured by stamping and brake forming which the desired shape is punch out and the bending part is bent simultaneously. The pin is made through forging process. As the pin is used as a hinge point for top and bottom half of the stapler, it is made from a strong, heat-treatable metal. Percentage of net shape manufacturing d) Finishing process Painting: As required to prevent rust or for cosmetic reasons, some components are painted. Some automatic painting operations employ electrostatic spraying, where the parts and paint are electrically charged. This method eliminates wasted paint. e) Cost of each manufacturing process Labour cost Material cost Go where find? f- Conclusion 2. List out DFM Rules ( one by one ) a) Reduce the total nu mber of parts. The reduction of the number of parts in a product is probably the best opportunity for reducing manufacturing costs. Less parts implies less purchases, inventory, handling, processing time, development time, equipment, engineering time, assembly difficulty, service inspection, testing, etc. b) Develop a modular design. The use of modules in product design simplifies manufacturing activities such as inspection, testing, assembly. These modules add versatility to product update in the redesign process, help run tests before the final assembly is put together, and allow the use of standard components to minimize product variations. c) Use of standard components. Standard components are less xpensive than custom-made items. d) Design parts to be multi-functional. Multi- functional parts reduce the total number of parts in a design, thus, obtaining the benefits given in rule 1 . e) Design parts for multi-use. In a manufacturing firm, different products can share parts that have been designed for multi-use. These parts can have the same or different functions when used in different products. f) Design for ease of fabrication. Select the optimum combination between the material and fabrication process to minimize the overall manufacturing cost. Final operations uch as painting, polishing, should be avoided. g) Avoid separate fasteners. The use of fasteners increases the cost of manufacturing a part due to the handling and feeding operations that have to be performed. Minimize the number, size, and variation used; also, utilize standard components whenever possible. h) Minimize assembly directions. All parts should be assembled from one direction. If possible, the best way to add parts is from above, in a vertical direction, parallel to the gravitational direction (downward). In this way, the effects of gravity help the ssembly process, contrary to having to compensate for its effect when other directions are chosen. i) Maximize compliance. Errors can occur during insertion operations due to variations in part dimensions or on the accuracy of the positioning device used. This faulty behavior can cause damage to the part or to the equipment. j) Minimize handling. Handling consists of positioning, orienting, and fixing a part or component. To facilitate orientation, symmetrical parts should be used whenever possible. b- Compare with existing design (see match with DFM rules or not)