西部地区深井井身结构设计技术探讨

科学合理地确定井身结构及钻井液密度是深井超深井钻井的关键环节之一，其基础是准确建立地层孔隙压力、地应力、破裂压力、坍塌压力的钻前预测剖面。分析了西部地区目前深井井身结构的缺点和进行井身结构应考虑的问题，介绍了深探井井身结构的设计方法，并针对西部复杂地区的地层特点，建议采用3种增加技术套管的井身结构方案。塔河油田钻井实践表明，采用这3种井身结构方案后，深井机械钻速得到提高，钻井周期缩短，而且降低了钻井成本。

Discussions on Casing Program Design Technology in Western China

Reasonable casing program and mud density designs based on accurate forecast profiles of formation pore, .stress, fracture and sloughing pressures, etc. are ones of the keys to drilling operations in deep and ultra-deep wells. This paper analyzes shortcomings of current deep-well casing schematics in China and considerations necessary to be taken into account, presents casing program design methods for deep-exploration wells. In addition, three special casing schematics with additional intermediate casing strings, suitable for the west complicated formations, are presented. Drilling practices in Tahe Oilfield indicate that the ROP in deep wells employing such three casing programs can be increased with Shortened drilling cycle and decreased drilling cost.