PURPOSE: To lessen variations of dimension accuracy of the product which is produced by the press, by forming the ram rod of the dieing press by use of the core rod and the sleeve pipe whose quality of material has little deformability to tension load and compression load.

CONSTITUTION: 4 pieces of ram rods 9 connecting the punch plate 10 and the ram plate 7 of the diening press are formed by use of the core rod 9a and the sleeve pipe 9b. The core rod 9a is made of Cr-Mo steel, etc. which have large tensile strength, the sleeve pipe is made of high speed steel, etc. which have large pressure resisting strength and hardness, and tensile strength and compressive strength are provided in the shaft direction as pre-pressure, respectively. The upper and lower end parts of the core rod 9a are made to penetrate into the punch plate 10 and the ram plate 7, while the sleeve pipe 9b is made to intervene between both the plates 10, 7, and also it is tightened with the nuts 14, 15 screwed to the male screws 9c, 9d on the end part of the core rod 9a. Thus, stretch resisting quality, compression resisting quality, abrasion resisting quality and strength are elevated, and it can be prevented that the dimension accuracy of the pressed product in case of pressure molding is deteriorated due to deformation of the ram rod 9.