摘要
大位移井由于其大斜度段和长水平段的环空间隙小 ,岩屑很容易在环空聚积形成岩屑床 ,进而在大位移井的钻进过程中极易发生井下复杂情况和安全事故 ,因此对大位移井进行井下不清洁的早期识别是一个极其重要的问题。为此 ,文章提出利用井下工具测量钻压、扭矩及环空压力 ,结合地面测量的数据 ,对井下不清洁情况进行比较精确的早期识别。其原理是 :通过井下钻压、扭矩和地面大钩载荷、扭矩计算出轴向摩阻系数和旋转摩阻系数 ,结合当量循环密度差来综合判别井下不清洁情况。其中 :当量循环密度差在应用中可以更明显地标示出井下不清洁情况。
Cuttings are easy to be piled up to form cuttings bed in annulus because of the narrow annuluses at the high-angle interval and long horizontal interval of extened-reach well, so that the downhole complication and accident will happen very easy in the process of drilling. For this reason, the early identification of downhole unclean circumstances in extended-reach well is a very important problem. In the paper it is proposed that more accurate early identification of downhole unclean circumstances may be carried out through measuring bit weight, torque and annulus pressure by downhole tools and in combination with surface measured data. Its principle is that on the basis of calculating axial friction resistance coefficient and rotary friction resistance coeffi cient by use of downhole bit weight and torque and of surface hook load and torque, the downhole unclean circumstances can be comprehensively identified in combination with equivalent circulating density difference which plays an important role in such an early identification.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2004年第8期42-44,共3页
Natural Gas Industry
基金
国家 8 6 3高科技项目 (2 0 0 1AA6 0 2 0 12 0 3B)部分成果
