The condensability of liquid,the Westphal's effect and the continuous flow condition are not only comprehensively considered,but also the dynamic property of the ball valve being established.

结合现场,据直线电机采油泵运特性,综合考虑了液体可压缩性、魏氏效应、液体连续流条件和球阀特性,建立了直线电机采油泵球阀运规律精确运微分方程组。