一种可溶剪切式管柱安全接头设计分析与应用  

Design analysis and application of shear string safety joint with soluble function

作　　者：李宁 任刚伟 孟令祥 陈亚丽 尚磊 LI Ning;REN Gangwei;MENG Lingxiang;CHEN Yali;SHANG Lei(Engineering and Technology Research Institute of Oil,Sinopec Zhongyuan Oilfield Branch,Puyang 457001)

机构地区：[1]中国石化中原油田分公司石油工程技术研究院,河南濮阳457001

出　　处：《机械设计》2024年第12期145-151,共7页Journal of Machine Design

基　　金：中国石油化工集团有限公司“特高含水油藏水驱提高采收率技术”项目资助(GC2106-03)

摘　　要：针对油田注水井管柱遇卡后,管柱提起困难和打捞卡点以上油管效率低的问题,文中设计了一种快速断开管柱的可溶剪切式管柱安全接头。通过理论计算和有限元仿真校核了3 000 N·m扭矩下所设计安全接头的强度,结果表明:最大应力出现在可溶锁块上,并且小于所选材料铝合金6061的屈服强度,能够满足强度要求。首先,模拟注水井井下环境,对密封性能进行了分析,通过计算得到的最大接触应力大于介质压力,能够满足密封性要求;然后,在高压釜内进行了3组可溶锁块溶解试验,得到了安全接头可溶锁块的平均溶解速率为15.49 mm/a,完全失效时间大约为4个月,能够保证工期内正常工作;最后,将其在现场试验两井次,已顺利下入管柱完成封隔器旋转和打压坐封。通过以上研究表明,可溶剪切式管柱安全接头作为管柱的配件,能够满足下入管柱时的拉压、扭转、密封要求和遇卡断开功能。In this article,in order to solve the difficulty in string lifting and the low efficiency in salvaging oil tubes above the stuck point when the oilfield water-injection well’s string gets stuck,a shear string safety joint with soluble function is designed for quickly disconnecting the string.The safety joint’s strength is checked when 3000 N·m torsion is exerted,by means of theoretical calculation and finite-element simulation.The results show that the maximum stress appears on the soluble locking block and is less than the yield limit of the selected aluminum alloy 6061,which meets the strength requirements.The sealing performance is analyzed by simulating the downhole environment of the water-injection well.The maximum contact stress is greater than the medium pressure,which meets the sealing requirements.Then,three groups of dissolution experiment are carried out on the soluble locking block in an autoclave.It is shown that the average dissolution rate of the soluble locking block for the safety joint is 15.49 mm/a and the time of complete failure is about four months,which ensures its normal function within the construction period.Finally,the string safety joint is tested twice on the spot;it successfully runs into the string for packer rotation and pressure setting.It is indicated that the shear string safety joint with soluble function,as the string’s accessory,meets the requirements of compression,torsion,sealing and flexible disconnection when running into the string.

关 键 词：安全接头 可溶锁块 强度校核 密封性 溶解速率 

分 类 号：TE937[石油与天然气工程—石油机械设备] TE921