摘要
大位移定向井、水平井钻井过程中,随井斜角增加,钻井液携带岩屑效率降低,形成岩屑床,影响钻井效率,易引发井眼安全事故。对市场在用的A型和B型两种带有螺旋槽结构的岩屑床清除钻杆,分别建立有限元模型,基于计算流体动力学(CFD)对相同工作条件下两种螺旋槽部位的环空流场进行数值模拟,从轴向速度场、切向速度场、动压力场三个方面分别对比两种螺旋槽流道结构对环空流体流动特性的影响。研究结果表明,A型清除钻杆相比于B型清除钻杆,在螺旋槽流域产生了更大的涡流和轴向速度,形成的低压区有利于岩屑卷入螺旋槽流道,使岩屑随钻具旋转甩向高压区,能有效冲刷、携带井眼环空流域的沉积岩屑。
With the inclination angle increased in extended reach wells and horizontal wells, the cuttings carrying by drilling fluid is harder, resulted in cuttings bed, low drilling performance and downhole accidents.Two helical groove structured hydroclean drill pipe subs commonly used now are studied.Finite element models of the two subs are established and their annulus flow fields are numerically simulated based on the computational fluid dynamics (CFD) under the same working conditions.The effects of two helical groove structures on the flow characteristics of annular fluid are compared in terms of axial velocity field, tangential velocity field and pressure field.The results show that type A drill pipe have a greater vortex and axial velocity produced in the basin of helical groove and a low pressure zone formed compared with type B.This is conducive for cuttings to be whirled into the helical channel, thrown into the high pressure area when the drilling tool rotated, so the cuttings bed in drilling annulus can be effectively scoured and taken away.
作者
屈文涛
郭怡潇
李桂变
胡海燕
QU Wentao;GUO Yixiao;LI Guibian;HU Haiyan(3.Shanxi Fenglei Drilling Tools Co.Ltd, Houma, Shanxi 043013, China;LWD Center, China Petroleum Logging Co.Ltd, Xi’an, Shanxi 710054, China)
出处
《钻采工艺》
CAS
北大核心
2019年第2期89-92,I0006,共5页
Drilling & Production Technology
基金
中国兵器工业集团民品科技开发项目"海洋钻井岩屑床清除专用钻杆科研开发及产业化"(兵科安字[2015]170号)资助
关键词
岩屑床
清除钻杆
螺旋槽
涡流
数值模拟
cuttings bed
hydroclean drill pipe
helical groove
vortex
numerical simulation
