The combined concave die must be pressed, how to correctly apply
7 Conclusion The advantages of this die are: strong versatility, only a part of the components can be extruded and a variety of piston pins can be extruded; The column guide sleeve type mold frame ensures the accuracy of the guidance; the angle of the upper and lower punches is improved, and the unit extrusion force is reduced; the use of a three-layer prestressed combined die increases the strength of the die and saves valuable molds
When the female die of the inner ring is damaged, only the inner ring needs to be replaced, and the entire combined female die will not be scrapped, which greatly reduces the manufacturing cost of the die. The combined concave die must be pressed, how to correctly apply the pre-stress to the inner cavity of the combined concave die during the pressing Strength is a very important issue.
The inner layer die is W18Cr4V, heat treatment hardness HRC60~65; middle layer prestressed sleeve is 40Cr and heat treatment hardness is HRC40~45; outer laminated sleeve is 45 steel and heat treatment hardness is HRC40~42. Although the relative sliding speed is not high, it is in a semi-liquid friction state at a temperature of about 1000), which is easy to cause wear. The actual unit of the die is subjected to a large squeezing force, and a three-layer prestressed combination die must be used to meet the requirements. To expand the support area, the convex The upper end of the die 12 is designed as a cone of 10.8 times the strength of the overall concave die. Therefore, the 2000kN hydraulic press (Y32-200) should be used for the pressing equipment.), the pressing force (multiplied by a safety factor of 1. The pressing method, the pressing angle is 1*30′, the pressing effect on the hydraulic machine is very good.1 Foreword Piston pin is an important basic part in internal combustion engine. Because it is subjected to a periodic alternating impact load (specific pressure is generally 30005000MPa), it is easy to produce fatigue damage. When cold extrusion, the cavity of the concave die is greatly affected.
4 Conclusion At present, my country has wholesale medical treatments mould built and put into operation dozens of connecting rod forging production lines, and its production capacity can fully meet the needs of the domestic market. To ensure the accuracy of the mold frame, To ensure the accuracy of the guide, the guide column guide sleeve type mold frame is used.