油管内对接井下电缆湿接头的研制与应用

Development and Application of Downhole Cable Wet Connector in Tubing

有缆数字式分注工艺需在油管外预置电缆,存在现场施工作业复杂、施工效率低及带压作业难度大等问题。为此,研制了油管内对接井下电缆湿接头。该湿接头主要由对接下体和对接上体组成,施工时对接下体随井下工具下井,完井后在井口利用电缆携带对接上体依靠重力与对接下体完成对接,对接下体的外接头总成设计有5个Φ20 mm的过流孔及解锁力为12~20 k N的锁紧机构,实现对接后长期稳定通信与供电、正常注水及重复对接利用。室内试验及现场应用结果表明:该湿接头设计合理、对接可靠,试验值与设计指标相符,满足注水井的作业要求。建议根据不同的井斜设计不同的加重短节,以便内、外接头可靠对接。所得结论可为优化有缆数字式分注工艺提供参考。

The cable-type digital separate layer injection technology requires preset cable outside of tu b in g’ presenting issues like complicated field operation ’ low operation efficiency and difficulty in snubbing operation. In view of this’ the downhole cable wet connector in tubing has been developed. The wet connector is mainly composed of the lower and upper body of butt join t. In operation’ the lower body was run with the downhole too l’ th e n’ the upper body was conveyed and run by cable at the wellhead to connect with the lower body using gravity after well completion. The pin end assembly of the lower body is designed with five 020 mm over flow port and locking mecha-nism with the unlocking force of 1 2？20 kN ’ so as to achieve long-term stable communication and power su pply’ water injection and repeated u se. The results of indoor test and field application show that the wet connector has rea-sonable design and reliable docking. The test value is consistent with the design index ’ meeting the operation re-quirements of the water injection well. Recommendation has been proposed to design different heavy weight joint ac-cording to different well inclinations to ensure the connection of the internal and external connectors. The study re-sults could provide references for optimizing the digital separate layer injection technology.