深井、超深井短尾管安全丢手关键技术研究

为提高深井、超深井短尾管固井施工的可靠性,针对深井、超深井摩阻大、短尾管固井悬挂尾管短和质量轻等原因造成的丢手不易判断的问题以及摩阻大造成的丢手困难的问题,通过采用尾管牵制技术及尾管悬挂器卡瓦内嵌技术,使尾管具有反向锚定锁紧及解锁功能,为短尾管提供附加载荷,便于现场施工安全丢手;制定了现场施工工艺流程,通过合理设计各级动作启动压力值,最终形成了适合于深井、超深井的短尾管安全丢手关键技术。该项技术已在塔河油田、青海油田及冀东油田等地区累计应用了72井次,成功率100%,应用最深井深为7271 m,最小规格为177.8 mm×Ф101.6 mm,尾管质量最轻仅为4.4 t。应用结果表明,该项技术有助于实现尾管悬挂器坐挂、丢手操作一次性成功,提高了短尾管固井施工的可靠性,为深井、超深井短尾管固井提供了有力的技术支持和施工保障。

Key Technology of Safety Release of Short Liner in Deep and Ultra-Deep Wells

The high drag in deep and ultra-deep wells makes releasing difficult and the short liner and light weight results in difficulty in identifying releasing.To improve the reliability of short liner cementing in deep and ultra-deep wells,the liner containment technology and liner hanger slip embedded technology are adopted to provide the liner with reverse anchoring locking and unlocking functions.With additional load for the short liner,liner hanger release is safer.The on-site operation process is formulated.Through reasonable design of the starting pressure values for each stage,a key technology for the safety release of short liner in deep and ultra-deep wells is finally formed.This technology has been applied in 72 wells in Tahe Oilfield,Qinghai Oilfield and Jidong Oilfield,with a success rate of 100%.The deepest well depth applied is 7271 m,the minimum specification of the tool is 177.8 mm×Ф101.6 mm,and the lightest liner weight is only 4.4 t.The application results show that the technology could help to achieve one-time success of the liner hanger setting and releasing operation,improves the reliability of short liner cementing,and provides technical support and guarantee for short liner cementing in deep and ultra-deep wells.