随钻无线传输技术分析与比较

Analysis and Comparison of MWD Transmission Technology

随钻无线传输方式主要有泥浆压力波、电磁波、声波3种。对3种传输方式的工作原理和影响信号传输的因素进行了分析和比较。泥浆脉冲传输方式深度适应强,但使用维护成本较高;电磁波传输方式受钻井介质影响小,可以用于气体、泡沫钻井,并能实现边堵漏边作业,且信号传输不依赖钻井介质循环,时效较高,但其传输衰减受地层电阻率影响较大,有些区块因信号衰减大无法完成全井段信号传输;声波传输方式不依赖钻井介质循环,可用于欠平衡钻井,且具有传输率高、受地层介质影响小的优势,但因信号衰减大,其传输深度受到限制。提高传输率与泥浆脉冲发生器的高温性能,增加电磁波转输方式和声波转输方式的传输深度是随钻无线传输技术的发展方向。

Mud pulse,electromagnetic wave and acoustic wave are three kinds of wireless transmission technology of MWD.Analyzed are the working principle and the influence factors of signal transmission and compared are the advantages and disadvantages.The transmission depth of mud pulse is deeper,the maintenance cost is higher.The electromagnetic wave is less influenced by drilling medium,so can be used for gas and foam drilling and plugging operation,signal transmission does not depend on drilling medium circulation,but the transmission depth depends on the formation resistivity,sometimes it cannot finish the full well operation.Acoustic transmission does not depend on the circulation of drilling medium and can be used for unbalanced drilling,and the transmission rate is higher and the influence is smaller by formation medium,but the transmission depth is restricted.It improves the transmission rate and high temperature performance of the mud pulser,increases the electromagnetic wave and acoustic transmission depth and transmission rate is the main development direction of MWD transmission technology.