Tool life and tool quality in bulk metal forming

Summary Due to their intermediate position between machine and workpiece, tools represent the interface of the manufacturing system to the process. Near net shape production, new materials and techniques are the new challenges in metal forming and specially in tooling. A significant economical effect can be achieved through an increase in the service time of tool elements, as well as through proper tool management strategies. The greatest problem connected with the preliminary estimation of tool life is the enormous dispersion of tool lives for the same construction of tool. The uncertainity in estimating the expected service time of tools and thus the tooling costs/piece is caused by enormous variety and confluence of damaging factors, factory-specific character of tool life, stochastic phenomenon of tool failures. From the confluence of aspects influencing the tool life it is clear, that there is no general recipe for increasing tool life and tool quality. Each of the influencing aspects contains some possibilities for increasing the service-time of tools. Paper shows some examples in tool design and tool manufacturing and points out, that a knowledge based approach can be the bridge between CA-techniques and human experience in prediction of expected tool life.

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