INFLUENCE OF SPACE BETWEEN HOLE AND PIPES ON DRILL PIPES’FAILURE

摘要

According to the practical problems encountered in horizontal directional drilling, arncomprehensive analysis of the main factors of drill pipes’ failure has been done.rnBased on the drill string dynamics, the paper have studied the influence on the drillrnpipes’ failure of the space between hole and pipes from the perspective of bendingrnstress, and proposed the measures for the prevention of drill pipes’ failure.