应用载荷法优化抽油机井热洗时机的探索与实践

Exploration and Practice of Optimizing Hot Washing Time of Pumping Unit Well by Load Method

喇嘛甸油田结蜡造成的杆断井占总检泵井的18.1%,且周期仅为492天。喇嘛甸油田洗井周期是根据电流得到的,而电流变化不能直接反映杆柱受力情况,如果参照交变载荷的变化判断热洗时机就有可能避免杆断,延长检泵周期。因此通过对抽油机井杆柱的受力情况进行理论计算,得到影响交变载荷最大的因素为抽油杆在空气中的重量和作用在活塞上的液柱重量。现场实测确定结蜡对电流及载荷的影响规律,即洗井初期与计算值相当,之后上载荷及交变载荷逐渐增大。根据历史数据及现场实测数据的分析研究,制定了载荷法洗井模板,确定抽油机井合理热洗时机。通过现场试验可知,应用载荷法洗井53口井后,免修期达到289天,与上次检泵周期相比延长169天。

The rod fracture caused by wax formation in Lamadian Oilfield accounts for 18.1%of the total inspection pump wells,and the period is only 492 days.The washing period of Lamadian Oilfield is obtained according to the current,and the current change cannot directly reflect the stress of the rod column.If the change of alternating load is used to judge the time of hot washing,the rod break can be avoided and the pump inspection cycle can be prolonged.Therefore,through theoretical calculation of the stress of the rod column of the pumping unit,it is found that the biggest factors affecting the alternating load are the weight of the rod in the air and the weight of the liquid column acting on the piston.The effect law of paraffin deposition on current and load is determined by field measurement,that is,the initial stage of well flushing is equivalent to the calculated value,and then the upper load and the alternating load gradually increase.Based on the analysis and study of historical data and field measured data,the load method of well washing template is established to determine the reasonable hot washing time of pumping well.According to field tests,53 Wells were cleaned by load method,and the maintenance free period reached 289 days,169 days longer than the last pump checking period.