Research Progress on Surface Design and Solid-Liquid Composite Lubrication Technology of Friction Pairs in High-Pressure Plunger Pumps

Plunger pumps， as one of the most critical power components in mechanical hydraulic systems， are widely used in aerospace， construction machinery and other fields due to their advantages of high rotational speed， high pressure， high transmission efficiency， diverse variable displacement mechanisms and high power density.In recent years， with the development of new-generation high-speed， high-pressure， intelligent and long-life mechanical hydraulic systems， more stringent adaptive requirements have been placed on the safety， stability and reliability of plunger pumps.The tribological performance of the three key friction pairs (plunger pair， valve assembly pair and slipper pair) of plunger pump under high-speed and high-pressure conditions is the critical factor limiting the service life of plunger pumps， determining the stability and reliability of mechanical hydraulic systems.This article first introduced the friction and wear problems of the three key friction pairs of plunger pumps and the forms of lubrication failure， and then summarized the surface treatment technologies for improving the friction and wear of the key friction pairs of plunger pumps and compared them.Finally， based on the service conditions and research status of plunger pumps， the issues that needed to be solved for the lubrication of plunger pump friction pairs in the new generation of mechanical design were proposed， and prospected these issues.