基于多参数测量柱塞的井底流压连续监测及应用

Continuous Monitoring of Bottom Hole Flowing Pressure Based on Multi-parameter Measuring Plunger and Its Application

为了连续监测井底流压,为井区压力监测、气井生产及排水采气策略的制定提供理论和实际指导数据,以井区柱塞井为研究对象,依托井下多参数测量柱塞内置的压力、温度和加速度传感器,经过内置算法得到柱塞运行过程中沿井筒的温度和压力分布,并对获取的井底流温和流压数据进行分析。结果表明,得到的柱塞运行过程中沿井筒的温度和压力分布,有助于分析气井积液和井下压力等生产状况。获取的流温流压数据准确可靠,Y4-3井使用井下多参数测量柱塞实施气举排水采气工艺后,套压下降速度缓慢,平均降速为0.0019MPa/d,年下降0.6935MPa;井底流压下降速率为0.0004MPa/d,低于井口套压的压降速率。井口套压的下降速率和井底流压下降速率并不一致,前者是后者的4.75倍,井口套压的变化并不能直接反映井底流压的变化,原因在于环空的积液量情况未知且较难预测。

In order to continuously monitor the bottom hole flowing pressure,to provide theoretical and practical guidance for the pressure monitoring in well area,gas well production and drainage gas recovery strategy,the plunger wells in the well area are studied as the object.Pressure,temperature and acceleration sensor are built into the multi-parameter measuring plunger.Built-in algorithm is used to obtain the temperature and pressure distribution along the wellbore during plunger operation,and the obtained bottom hole flowing temperature and pressure data are analyzed.The results show that:the obtained temperature and pressure distribution along the wellbore during plunger operation can help analyze production conditions such as gas well liquid loading and downhole pressure.The obtained flowing temperature and pressure data is accurate and reliable.After the downhole multi-parameter measuring plunger is applied to gas lift drainage gas recovery process in Well Y4-3,the casing pressure dropped slowly with the average decrease rate of 0.0019MPa/d and annual decrease of 0.6935MPa.While the decrease rate of bottom hole flowing pressure is 0.0004MPa/d,which is lower than that of wellhead casing pressure.The decrease rate of wellhead casing pressure is not consistent with that of bottom hole flowing pressure,which is 4.75 times that of the latter,so the change of wellhead casing pressure cannot directly reflect the change of bottom hole flowing pressure.The reason is the liquidloading volume in the annulus is unknown and difficult to be predicted.