The alternate experiments of top clearance pump element,normal pump element without top clearance,constant pres- sure delivery valve and damping valve in fuel injection pump are made.

Research on Consistency of Pump with Top Clearance Plunger;

Research and Developing on Fuel Injection Pump with Top Clearance Plunger;

Ceramic plunger couples have been favored by engine designers for their excellent properties such as wear resistance,corrosion resistance and so on,but their use have been severely restricted because of their complicated technics and machining.

In order to use engineering ceramics to make plunger couples instead of metal,stress and displacement distributions for plunger couples made of different materials were studied under the engine rated power,and the change regulations of clearance were analyzed.

Use the Water Base Cleaning Process,Improve Cleanliness of Plunger and Barrel Assembly;

The most important factor that causes plunger matching parts failure of injection pump on the high pump end was analyzed in this paper,and the necessary tests was done.

By analyzing the sealing and lubrication of the plunger matching parts of the fuel injection pump with the oil film theory and gap liquid flow theory, a basic theory and the analytic method are proposed to set the smallest gap between the plunger matching parts.

FEA and testing researches are conducted to calculate the deformation and leakage of the plunger assembly clearance during its working process,and further optimization design is finished for better dynamic sealing-performance under-super-pressure condition.