关键词: 径向水平井, 斜向器, 钻杆截面, 受力分析, 塑性变形, 轴向应力

Abstract: Ultra short radius horizontal radial drilling is a novel oil drilling and exploitation technology.During drilling operation,when drill pipe passthrough whipstock rollerpass,the varying curvature radius of drill pipe cause the bending drill pipe behaves plastic state.Deformation of the pipe cross section and the relevant drag force from the whipstock pass highly affect horizontal advan cing capability of the drill pipe.This paper,the ideal rigid plastic analysis based on the stress strain relation of the pipe is presented the equations of the long axis and short axis extreme values of the elliptically deformed pipe cross section,and of the bending whipstock resistance exerting on advancing drill pipe.The effects of the roller pass friction and the reverse force of water jet on the pipe advancing resistance are analyzed.The equation in this paper are verified by experiments under various conditions,and they are of practical importance in designing whipstock selecting pipe material and optimizing parameter.

Key words: ultra short radius horizontal radial drilling, whipstock, cross-section of drill pipe, stress, analysis plastic deformation, axial stress