39results about How to "Reduce pull strength" patented technology

The utility model relates to an extrusion die for a cylindrical forged steel inside and outside reducing closing-in piece. The die comprises a lower cushion block, a lower die, a lower punch, an upper punch and an upper die, an upper die inner hole is arranged in the upper die, the upper end of the upper punch is arranged in the upper die inner hole, the lower end of the upper punch is fixedly connected with the upper end of the lower punch, a lower die inner hole is arranged in the lower die, the lower end of the lower punch can be embedded in the lower die inner hole, and the lower cushion block is arranged at the bottom of the lower die inner hole. According to the utility model, the technical problems of low production efficiency, uncontrollable inner wall quality, poor concentricity, high production labor intensity and the like of the inner and outer diameter change of the cylindrical forged steel in the background technology are solved, and the yield and the working efficiency are improved.