大斜度井段岩屑床厚度计算模式研究

水平井、大位移井可以大幅度提高油气采收率，在油田开发中得到了广泛的应用，但该井型的水平井段尤其是大斜度井段易出现井眼清洁问题，造成卡钻等事故，从而影响机械钻速和井下安全，制约了复杂结构井技术的发展。深入研究了水平井及大位移井的大斜度井段岩屑运移规律，考虑钻柱旋转和颗粒间作用力的影响，分析岩屑受力情况，建立了环空岩屑床厚度计算程序，并进行了相关参数的敏感性分析，探究了钻井液排量、岩屑直径、流性指数、钻井液密度、钻杆偏心度、钻杆转速等对岩屑床厚度的影响。

Study on thickness calculation model of cuttings bed in highly-deviated well sections

The horizontal well and extended-reach well can greatly improve the recovery ratio of oil and gas，so the horizontal well and extended-reach well are widely used in the development of marine oil field. However，the poor hole cleaning in the highly-deviated sections and horizontal sections leads to sticking pipe and other accidents，which affects the rate of drilling and underground safety. This has restricted the technology development of complex structure well. Therefore this paper explores further the rule of cuttings transport in the highly-deviated sections of the horizontal well and extended-reach well，considering the influence of the drill string rotation and particles interaction forces. The force conditions of cuttings were analysed，the calculation program of annular cuttings bed thickness was established，and the sensitivity analysis of related parameters have been carried out. Finally，the influence of drilling fluid displacement，the diameter of cuttings，the drilling fluid flow index，the density of drilling fluid，the drill pipe eccentricity and the rate of drilling on cuttings bed thickness was also explored.