柔性连续抽油杆超冲程问题探讨

Discussion on Flexible Continuum Rod with Increased Downhole Pump Stroke

针对国内柔性连续抽油杆在应用中强调柔性杆容易实现超冲程的观点,引述理论界对于柔性连续抽油杆柱塞超冲程的讨论,依据杆柱一维振动模型阐述柱塞超冲程的相关问题,说明不同阻尼下实现放大系数最大时的频率比随阻尼系数的变大而变小。提出出现超冲程时必然会伴随着超载荷;在过阻尼的情况下,杆柱不但不会出现超冲程,反而会出现超冲程损失;柔性杆的应用应该以柱塞的实际冲程作为设计依据;柔性杆相对超冲程的量一般比液载的额外冲程损失小,正是钢丝绳弹性模量大而优于其他柔性杆的关键原因;柔性连续抽油杆的单井优化设计应该以加重杆满足柔性杆不受压为主要设计依据。

The discussion on Flexible continuum sucker rod relative/ absolute increased downhole pump stroke is presented. Based on the one dimension vibration equation to expatiate the rules of increased downhole pump stroke, the frequency ratio corresponding to the Max Magnify Coefficient increased along with the Damping Coefficient, relative increased downhole pump stroke must lead to increased load, excessive Damping Coefficient will not relatively increase downhole pump stroke emergence, but relative losing downhole pump stroke, design flexible continuum rod should not pursue relative increased downhole pump stroke. Because Young＇s modulus of steel wire rope rod was close to conventional steel sucker rod, its stroke efficiency excelled carbon-fiber rod and fiberglass rod, design Flexible continuum rod should ensure the Flexible continuum sucker rod not to be pressed in the downwards stroke.