Advantages of backward extrusion include simplicity of tooling and ease of removal of the shell after forming. However, the process has limitations. The punch must be long enough to accommodate the entire length of the shell, plus an allowance for trimming, and a long stroke press is frequentl required. There is therefore a limit to the length of the part that can be formed by the procedure. Further, in the extrusion of long shells the punch has a tendency to float and this tendency is increased by play in the moving head of the press. As a result, there is some difficulty in maintaining uniform wall thicknesses in long extrusions.
(Design for manufacturability handbook, J.G. Bralla, pg. 3- 121)
Fine Blanking: The fine blanking process is a press-working technique that utilizes a special press and precision tools and dies to produce parts that are more nearly complete and ready for assembly as they leave the fine blanking press than parts blanked by conventional methods. Fine blanking produces parts with cleanly sheared over the entire material thickness. By comparison, cpnventionally stamped generally exhibit a cleanly sheared edge over only approximately one third of the material thickness and the remainder shows fracture. With conventional stamping, when these surfaces are functional, they may require some form of secondary operation such as shaving, milling, reaming, broching, hobbing or grindidng. often, several of these operations are necessary to the complete part. Apart from the improved quality of the sheared surfaces when fine blanking is used, high dimensional accuracy can be obtained and the process also allows operations that cannot normally be accomplished in conventional stamping dies.
(Design for manufacturability handbook, J.G. Bralla, pg. 3- 43)
SCOR: The Supply Chain Operations has been developed to describe the business activities associated with all phasesof satisfying a customer' s demand. The model itself contains several sections and is organized around the five primary management processes of plan, source, make, deliver and return. By describing supply chains using these process building blocks, the Model can be used to describe supply chains that are very simple or very complex using a common set of definitons. As a result, disparate industries can be linked to describe the depth and breadth of virtually any supply chain. The Model has been able to successfully describe and provide a basis for supply chain improvement for global projects as well as site specific projects.
(The Hitchhiker's Guide to Manufacturing Operations Management, Charlie Gifford, pg. 105-106)
Quick Response Manufacturing (QRM): The Quick Response Manufacturing System is based on the quick response concept with the purpose to quick response to the demand for developing new products and carry out of design and manufacturing process in a very timely manner. The frequent changing of market demand requires higher competence of new product development. On one hand, companies need to analyze its current development and manufacturing system to estimate, from the perspective of mission reliability, system' s ability to finish the task in the required time period. On the other hand, companies may also need to improve on those weaknesses that pertain to the system therefore increase its competence of development.
(Computational science, Yong Shi, pg. 202)
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