Research On Performance Degradation Of Heavy-Duty Swashplate Piston Pump Based On Wear Data

Plunger pump is widely used in aerospace,engineering machinery,military and other fields.With the increasing demand for use,there are higher requirements for its use pressure.As the working pressure of the plunger increases,the overturning moment increases,which will aggravate the wear of the plunger pair,and then reduce the volume efficiency of the plunger pump,affecting the reliability of the plunger pump.The performance degradation of plunger pair due to wear is one of the indexes to evaluate pump service condition.Therefore,it is necessary to study the wear variation of the plunger pair under heavy load condition,so as to provide a theoretical basis for evaluating the reliability of the pump under heavy load.This paper takes heavy-duty swashplate piston pump as the research object,and the main research contents are as follows:Firstly,the kinematics analysis of plunger is carried out,and the force balance equation of plunger is established based on the kinematics analysis,the force on plunger under heavy load is analyzed.The clearance change of plunger pair under heavy load is studied,and the formula for calculating the leakage of plunger pair and other friction pairs is derived,the leakage performance of piston pump under heavy load was obtained.Secondly,according to the results of force analysis and dynamic analysis of the plunger pair contact force results,combined with the working speed of plunger pump,determine the plunger pair of material friction and wear experimental conditions.The friction and wear characteristics of the matched materials of plunger pair under different rotating speeds and pressure conditions are studied,which lays a foundation for deducing the actual wear of plunger pair from experimental data.Thirdly,according to the experimental results of friction and wear and the relationship between the actual working geometry of the plunger pair and the force,the change rule of the piston pair leakage with the cumulative wear time was obtained by using the wear model of the friction pair,and the change rule of the volume efficiency of the plunger pump with time was studied under different pressure and cylinder speed conditions.The life prediction method of plunger pump is put forward,which provides reference for life prediction of plunger pump.Finally,the whole pump volumetric efficiency test was completed to determine the no-load displacement of the plunger pump,test the leakage amount and volumetric efficiency of the plunger pump under different working pressures and cylinder speed,and verify the reliability of the theoretical research.