Abstract: Powder metallurgy hand tight nuts for power tools, used in hand tight drill chuck, the demand is very large. The shape of the hand tight nuts is complicated, and the research and development personnel jointly analyze the various problems that may occur in the forming process, and put forward different forming schemes. The upper part of the forming is made of two structural die punching, one is to make an upper punch to simplify the mold, the other is the upper outside punch and the upper inside punch, which is split at the chamfering Angle to solve the problem that the upper punch may be cracked by lateral pressure. The mold design scheme of the lower part of the hand tight nuts masterbatch is analyzed, and the problem of easy damage due to the thin punching wall under forming is reasonably solved. Combined with 3D design software, a reasonable mold is designed to meet the requirements of accuracy, density, size and performance, to reduce costs and improve production efficiency.