Abstract: Aiming at the problem that the press frequency of 250T metal powder sizing hydraulic press could not meet the needs of design, the main factors affecting the pressing frequency, such as the cylinder speed of lower inner die, the damping of pump outlet cartridge valve and the stroke of the slide block were studied. The working principle of the hydraulic system of 250T metal powder sizing hydraulic press was analyzed. The model of DG25 directional cartridge valve was built by AMESim, and the correctness of the model was verified through simulation. The simulation model of the hydraulic system of the 250T metal powder sizing hydraulic press was built, and the influences of the cylinder speed of lower inner die, the damping of pump outlet cartridge valve and the stroke of the slide block in the single pressing period were studied respectively. The results indicate that increasing the cylinder speed of lower inner die, increasing the damping size of the pump outlet cartridge valve and shortening the stroke of the slide block can effectively shorten the single pressing cycle of the press, increase the pressing frequency, the single time is controlled at 6.1 s, and meet the requirements of design.

Key words: hydraulic press system; metal powder sizing; press frequency; simulation model