螺杆泵井抽油杆共振影响因素分析及应用

Analysis and application examples on resonance influence factors for oil pumping rod of screw pump well

抽油杆有其固有频率,当抽油杆运转时产生的振动频率等于抽油杆的固有频率后,会产生共振,使振幅增大,加剧螺杆泵抽油杆和油管的偏磨。为了减轻共振对螺杆泵井抽油杆偏磨的影响,从螺杆泵抽油杆横向振动共振的产生条件入手分析,通过下泵深度和杆径计算出共振频率,由此得出发生横向振动共振时的抽油杆转速,进而指导现场采用合理转速生产,消除抽油杆以发生共振转速运转,消除共振对螺杆泵井抽油杆偏磨的影响。

Pumping rod has its natural frequency, when the vibration frequency of pumping rod equals to its natural frequency, the resonance phenomenon will appear, and the vibration amplitude will enlarge, which will exacerbate the eccentric wear between pumping rod and tubing. In order to mitigate the influence of resonance on eccentric wear between pumping rod and tubing,starting from the analysis on transverse resonance generating condition of pumping rod and the calculation of the resonance frequency from rod diameter and pump depth, the rotation speed of pumping rod can be obtained when the transverse resonance occurs,then it can be used to guide the field production to use reasonable rotation speed, so as to avoid the occurrence of resonance phenomenon,and then the influence of resonance on the eccentric wear of pumping rod can be prevented.