螺杆泵井转速对泵效的影响研究与应用

Research and Application of the Effect of Rotate Speed on Pump Efficiency for Screw Pump Wells

螺杆泵生产过程中,影响泵效的因素包括定(转)子过盈值、转子转速、液体黏度、含气量、泵沉没度等。其中,转速的选择尤为重要,合理的转速应与油井工况及螺杆泵的结构参数相匹配。如果转速选择不当,则螺杆泵高效节能的优点不能发挥,导致泵效下降,甚至影响螺杆泵寿命。针对如何提高井下螺杆泵泵效问题,从螺杆泵转速对油井的泵效影响分析入手,阐述螺杆泵转速对泵效的影响机理,并通过分析不同环境下转速对泵漏失、泵充满度的影响关系,拟合出理论计算公式;通过室内试验与现场应用,得出在井下工作环境中,转速对泵效的影响关系为反比关系,即转速越低,泵效越高。分析结论认为,针对井下工作环境,合理增大螺杆泵排量,适当降低转速,不仅可以提高螺杆泵的泵效,发挥其高效节能特点,在一定程度上还可减少螺杆泵的磨损,延长油井检泵周期。

During the production of the screw pump,the influencing factors of pump efficiency include stator(rotator) interference value,rotate speed of rotator,viscosity of the liquid,gas concentration,submergence depth and so on.Among them,the rotate speed is more important that should be matched with operational mode of oil wells and structural parameter of the screw pump.Unsuitable rotate speed may result in the drop of the pump efficiency and even in shorter life for restraining the advantage of high efficiency and energy saving of the screw pump.In the light of the problems of improving pump efficiency of screw pump,through the analysis of the effect of rotate speed on pump efficiency for oil wells,effect mechanism of rotate speed on pump efficiency is analyzed,and theoretical calculation formula is matched after analyzing the relation of rotate speed on pump loss and degree of fullness under various downhole environments.Inverse relation of rotate speed and pump efficiency underground is known by laboratory test and field application.The lower the rotate speed is,the higher the pump efficiency is.Rational increasing pump displacement and reducing rotate speed can not only improve pump efficiency,but also reduce the wear of rod and pump to a certain extent and prolong the period of pump inspection.