This paper presents drilling fluid technology used for big hole,big clearance of annular,owl returning velocity while drilling collapsing complicate formation,that is polymer/MMH drilling fluid.

• 本文介绍了一种应用于大井眼、大环空间隙、较低返速条件下钻易垮塌等复杂地层的钻井液技术，即两性钻井液技术。