超深井随钻测量仪器适应性分析

Adaptability of the measurement-while-drilling equipment in ultra-deep wells

随着对深部油气藏的陆续开发，深井超深井数量逐步增多。由于井深的增加，对随钻测量仪器的抗高温、耐高压性能都提出了更高的要求，同时长距离传输的脉冲信号衰减超出仪器解码范围的问题也屡见不鲜，制约了上述仪器的使用。通过在川东北多个工区的随钻测量实践，总结了不同井深和温度条件下随钻测量仪器的选用原则：①垂深在5000ITI以内的井，有很多MWD仪器可供选择；②垂深介于5000～6000m的井，如果井底温度不超过130℃、井底循环动压不超过17000psi（约117MPa），HALLIBURTON公司生产的MWD仪器以其工作的稳定性高得到比较普遍的认可，若温度或压力超过这个指标，则可用BAKERHUGHES公司生产的MWD仪器或GE公司生产的GEOLINKMWD仪器；③垂深超过6000m时，推荐使用BAKERHUGHES公司生产的MWD仪器或GE公司生产的GEOLINKMWD仪器，若温度进一步升高或改良脉冲信号的措施无法实施时，则要引入抗温性能更高的MWD仪器。还结合工程实例体会，进一步总结了不同仪器在超深井中的适用情况及改良措施。

With the exploration of deep-buried reservoirs,the number of ultra-deep wells with the depth larger than 6000 or 7000 m is gradually increasing.Because of the increase of vertical depth,the measurement-while-drilling(MWD) equipment often has to work under much higher temperature and higher pressure.On the other hand,mud pulse signals must transmit even longer distance in viscous drilling fluids that can generate much more attenuation,the MWD equipment can not gain effective signals in some cases.The performance of different MWD equipment in ultra-deep wells is presented based on several case studies.Through practices in many fields of the northeastern Sichuan Basin,principles to choose suitable MWD equipment for different well depths and temperatures are summarized.(1) For wells with the total vertical depth within 5000 m,many kinds of MWD can be used.(2) For wells with the total vertical depth of 5000-6000 m,if the BHT is not over 130℃ and the dynamic circulation BHP is not over 17000 psi(about 117 MPa),the HALLIBURTON's MWD can be used due to its high stability,but if for much higher BHT and circulation BHP,the BAKER HUGHES' MWD or the GE's GEOLINK MWD can be used and both can be recommended for wells with the total vertical depth over 6000 m.And if the temperature is even higher or pulse improvement fails to be fulfilled,the MWD with even higher temperature performance will be introduced.In the end,based on the cases history,the adaptability and the improvement measures are summarized for different types of MWD in ultra-deep wells.