Die design of powder metallurgy hand tight nuts used for power tools

The structure of powder metallurgy hand tight nuts used for power tools is complex. The reasonable die structure and size were found out in this paper by the careful analysis of product structure and forming process, combining with 3D design software and actual production practice. In the results, after sintering the pressed products at high temperature, the density and size of the products meet the design requirements, and successfully pass the testing of testing center and customer. Mass production of powder metallurgy hand tight nut dies for power tools are prepared by 30 t mechanical press pressing, the structure of which includes two up and two down. The overall pressed products by up-punching forming are cracked and scrapped when 5000~7000 pieces are produced. Pressing products by the outside and inside punching forming, the dies are worn and need to be repaired after the production of 100000~120000 pieces of hand tight nuts. Using the forming scheme of the outside and inside punching, the die service life is increased, the production cost is reduced, and the produced powder metallurgy hand tight nut dies for power tools fully meet the design requirements.