煤层气小井眼大位移井完井技术研究及应用

Research And Application Of Completion Technology for Slim Hole Extended Reach Well Of CBM

煤层承压能力低,固井过程中易造成井漏,煤层段固井质量无法保证,漏失的水泥浆对煤层产生不可恢复的伤害等严重问题,导致单井产量低,严重制约了煤层气开发效益;如何实现固井质量高,层间封隔好,固井施工对煤层的伤害小成为当下亟需解决的难题。采用刚性旋流扶正器优选和安放设计、优选增韧水泥浆体系和TS早强降失水剂、顶替模拟及水泥环完整性分析等技术,通过现场试验有效解决了煤层气小井眼大位移井完井存在的难题,形成了小井眼大位移井完井特色技术。

The coal seam has low pressure bearing capacity,which is easy to cause well leakage in ce-menting process,the quality of cementing in coal seam section can not be guaranteed,and the lost cement slurry causes irreparable damage to the coal seam,which leads to low single well production,which seri-ously restricts the development benefit of CBM;How to achieve high cementing quality,good interlayer sealing and small damage to coal seam by cementing construction have become the urgent problems to be solved.The problems existing in the completion of small displacement wells in coalbed methane wells are effectively solved by field tests,such as the optimization and placement design of rigid swirl centralizer,the optimization of toughening cement slurry system,TS early strength loss reducing agent,displacement simulation and integrity analysis of cement ring.