A Drainage Sealing Method and Experiment in Injection-Production Wells with High Temperature and High Pressure

Because the mechanical research of downhole tubing is limited by the downhole mechanical detection device, a “pressure cap + ferrule” drainage sealing method is proposed to meet the drainage sealing requirements of the downhole mechanical detection device. The drainage sealing device has been manufactured and the indoor pressure seal experiment has been carried out. The results showed that the drainage sealing device met the sealing requirements of 30 MPa hydraulic pressure, and 80 °C high temperature using the pressure-resistant sealing experimental device. The drainage sealing device was installed on the downhole mechanical detection device, and the whole equipment was lowered to the DXX-162-X20 well of Shengli Oilfield to carry out the downhole experiment. The drainage sealing device worked in the downhole environment of 0–100 °C and 0–30 MPa, and successfully detected the downhole fluid pressure. The drainage sealing method proposed in this work provides reference for the research of downhole mechanical detection device, and is helpful for the mechanical research of downhole tubing, and reduces the injection-production operation accidents.