ERD wells are widely adopted due to its great economic benefits and its applicability fur special purposes, while the drag along the horizontal section has limited the promotion of ERD wells.

• 摘要大位移井技术因其具有巨大经济效益并能够满足特殊作业的目的而得以迅速推广应用，但水平井段摩阻扭矩又成为了制约大位移井推广应用的关键因素。