国内3 000 m长水平段水平井钻井实例与认识

超长水平段水平井技术已经成为低渗透、非常规油气资源开发的重要技术保障，国内已钻成了多口3 000 m及以上长水平段水平井。由于水平段过长，导致摩阻扭矩大、井眼轨迹控制难、井眼清洁困难、钻压施加难、井壁稳定性差等问题。针对这些难点梳理了3 000 m及以上长水平段水平井钻井的关键技术，包括井眼轨道优化设计、井眼轨迹控制、钻井液性能提高、降摩减阻和“一趟钻”等。在此基础上提出了3 000 m长水平段水平井技术发展方向，以助于提高该技术的应用效果和技术整体水平。

Cases and understandings on the drilling of horizontal well with horizontal section of 3 000 m long in China

The horizontal well technology with ultra-long horizontal section has already become the important technological guarantee for the development of low permeability and unconventional oil and gas resources. And many horizontal wells with the horizontal section at least 3 000 m long have been completed in China. Long horizontal section results in a series of problems, such as large torque and drag, difficult hole trajectory control, difficult hole cleaning, difficult WOB application and poor well stability. To deal with these difficulties, this paper analyzed the key technologies for drilling the horizontal wells whose horizontal sections are at least 3 000 m long, including hole trajectory optimization design, drilling fluid performance improvement, friction reduction and “one-trip drilling”. Then, the development direction of the horizontal wells with horizontal section of 3 000 m long was put forward, so as to improve its application effect and overall level.