水力活塞泵工作过程故障诊断的理论研究

水力活塞泵在工作过程中因换向阀上下冲程的瞬时换向而产生水击。这对油管中流体流速的急剧变化，引起压力急剧变化。根据水力活塞泵换向阀水击运动方程和连续方程，导出了描述水力活塞泵工作过程的工作状态方程组，准确地表征了这种泵工作过程中流量、压力随时间的变化规律。通过对水力活塞泵运动状态的水击理论讨论和数学模型的建立，为进行水力活塞泵参数监测和故障分析奠定了理论基础。建议利用导出的泵工作状态实际模型，配套研制地面测试仪表，完善水力活塞泵的井下诊断技术。

Theoretical analysis of fault diagnosis of hydraulic piston pump

In the course of work of a hydraulic piston pump, water hammer occurs owing to instantaneous reverse of the up stroke and downstroke of the slide valve, and the rapid change of the flow rate of the fluid in the tubing string causes the rapid change of the pressure. Based on the water-hammer motion equation and continuity equation of the reversing valve of a hydraulic piston pump, the equation set for describing the course of work of the pump is derived, thereby the varia tion pattem of the flow rate and pressure with time can be expressed precisely. The theoretical analysis of the motion con dition of the hydraulic piston pump and the establishment of the relevant mathematical model provide a basis for the pa rameter menitoring and fault diagnosis of the pump. It is recommended to develop the surface testing instriments by using the wothing condition model of the pump obtained.