抽油杆柱的纵向振动特性与共振条件

Longitudinal vibration characteristic and resonance condition of sucker rod string.

针对美国中西部研究所关于抽油杆柱纵向振动研究力学模型存在的问题 ,在研究抽油杆柱纵向振动特性时 ,提出将抽油杆柱简化为上端固定于随悬点运动的基础之上 ,下端受液体载荷激励的力学模型。得出单级抽油杆柱纵向自由振动的固有频率以及抽油杆柱对悬点运动和泵柱塞液体载荷两种激励的稳态响应计算公式。指出单级抽油杆柱产生共振的条件是激励频率等于基频的奇数倍。证明APIRP11L《有杆抽油系统的设计计算推荐方法》中关于激励频率等于基频偶数倍时单级抽油杆柱将产生共振的结论是错误的 。

A new mechanical model for analyzing the longitudinal vibration characteristic of the sucker rod string is set up, and the natural frequency and steady responses to exciting forces are studied. The resonance condition of single stage rod string is that the exciting frequency is equal to odd times of the basic frequency. Theoretical analysis and deducing show that the resonance condition of single stage rod string stipulated in API RP 11L is unreasonable because of incorrect mechanical model being used.