Analysis of the causes of rapid damage of forging tools

摘要

The article presents an analysis of the causes of the occurrence of premature damage and failure of dies and punches at an early stage of operation, as compared to the "typical", predictable and proceeding wear of forging tools. At present, in Europe and the world, numerous studies are being performed aiming at increasing the durability of forging tools. The latter is usually determined by the number of forgings properly produced by the given tool in respect of geometry and quality. It is assumed that, in the case of tools used in hot forging processes, the average tool life is about 5000 forgings, and the factors and mechanisms shortening the operation time have been quite well analyzed. In turn, the subject literature provides little information on preliminary damage of forging instrumentation. An analysis of such numerous cases presented in the study as well as the authors' experience point to the fact that the most common cause of rapid failure are problems connected with inappropriate thermal treatment (38%), improper mechanical treatment of tool surfaces (21%), faulty tool material (16%), errors resulting from the took' improper preparation for work (15%), inappropriately elaborated forging technology (6%) and others (4%). It should be emphasized that preliminary wear is also significantly affected by the human factor, which, often, consciously or unconsciously, contributes to the occurrence of an unexpected event causing rapid damage or failure. The presented analysis aims at contributing to the recognition of the causes of such type of damage as well as their effective elimination.