磁力随钻测量磁干扰校正方法研究  

Method of Magnetic Interference Correction in Survey with Magnetic MWD

作　　者：许昊东 黄根炉[1] 张然 韦红术 程锋瑞 

机构地区：[1]中国石油大学(华东)石油工程学院,山东青岛266580 [2]中国石油阿姆河天然气公司钻井部,北京102206 [3]中海石油(中国)有限公司深圳分公司,广东深圳518000

出　　处：《石油钻探技术》2014年第2期102-106,共5页Petroleum Drilling Techniques

基　　金：中海石油有限公司科技攻关项目"陆丰低渗油气藏测试工程联作关键技术研究"(编号:CCL2012SZPS0005)资助

摘　　要：为提高磁力随钻测量的井眼轨迹精度，研究了随钻测量磁干扰校正方法。利用随钻测量参数，计算井斜角、工具面角和方位角；采取360＆#176;旋转钻柱记录、分析径向磁力计读数的方法，纠正磁热点引起的径向磁干扰；采用循环迭代的方法，纠正钻柱磁化引起的轴向磁干扰。通过仿真测量参数、磁干扰数据和地磁参数，应用磁干扰校正方法计算得到校正方位角，并与实测方位角、真实方位角进行了对比，结果发现，在其他井眼参数保持不变的条件下，井斜角接近90＆#176;或方位角接近90＆#176;、270＆#176;时，实测方位角误差变大；井斜角接近0＆#176;或方位角接近0＆#176;、180＆#176;时，实测方位角误差变小；真实方位角为0＆#176;～180＆#176;时，实测方位角比真实方位角小，真实方位角为180＆#176;～360＆#176;时，实测方位角比真实方位角大；井眼轨迹接近水平东或水平西方向时，轴向磁干扰的校正效果最差。磁干扰校正方法能够提高方位角测量精度，减少无磁钻铤长度。In order to improve accuracy of well trajectory measured by MWD ,magnetic interference correction was studied .Inclination angle ,tool-face and azimuth angle were worked out when surveying with magnetic MWD .Cross-axial magnetic interference originating from magnetic hot spots in the NMDC was corrected by rotating drillstring 360＆#176; and analyzing cross-axial magnetometer data .Axial magnetic interfer-ence originates from the magnetization of ferromagnetic portions of the drill string was corrected by loop it-eration method .A series of conclusions were reached by a group of simulation data including survey data , magnetic interference data and geomagnetic parameters ：the error of measured azimuth was larger when in-clination approaches 90＆#176; or azimuth approaches 90＆#176; ,270＆#176;;the error of measured azimuth was smaller when inclination approaches 0＆#176; or azimuth approaches 0＆#176; ,180＆#176;;the measured azimuth was smaller than true azi-muth when true azimuth was between 0＆#176; and 180＆#176;;the measured azimuth was larger than true azimuth when true azimuth was between 180＆#176; and 360＆#176;;the effect of correcting axial magnetic interference was poo-rer when trajectory approaches horizontal west or east and the correcting algorithm was stable .

关 键 词：径向磁干扰 钻柱磁化 轴向磁干扰 方位角 

分 类 号：P631.8[天文地球—地质矿产勘探]