Method for the detection and correction of magnetic interference in the
surveying of boreholes
    11.
    发明授权
    Method for the detection and correction of magnetic interference in the surveying of boreholes 失效
    在钻孔测量中检测和校正磁干扰的方法

    公开(公告)号:US4761889A

    公开(公告)日:1988-08-09

    申请号:US905979

    申请日:1986-09-10

    IPC分类号: E21B47/022

    CPC分类号: E21B47/022

    摘要: A method is presented, for use in borehole drilling, for correcting errors in azimuth determination resulting from variations in the earth's magnetic field to which a measuring instrument is exposed. The method distinguishes between variations in the earth's magnetic field caused by the drillstring and variation caused by external sources, and the method corrects only for errors caused by the drillstring. If the error is caused by the drillstring, an azimuth correction is made based on dip angle data, thereby reducing errors caused by scale factor variations since dip angle is a ratio quantity of magnetic field components.

    摘要翻译: 提出了一种用于钻孔钻孔的方法,用于校正由测量仪器暴露于其中的地球磁场变化引起的方位测定误差。 该方法区分由钻柱引起的地球磁场变化和外部源引起的变化,该方法仅对钻柱引起的误差进行校正。 如果误差是由钻柱引起的,则基于倾角数据进行方位角校正,从而减少因尺度因子变化引起的误差,因为倾角是磁场分量的比值。

    Method for evaluation of formation invasion and formation permeability
    14.
    发明授权
    Method for evaluation of formation invasion and formation permeability 失效
    地层入侵和地层渗透性评价方法

    公开(公告)号:US4716973A

    公开(公告)日:1988-01-05

    申请号:US941390

    申请日:1986-12-15

    申请人: Martin E. Cobern

    发明人: Martin E. Cobern

    IPC分类号: G01V3/20 E21B49/00

    CPC分类号: G01V3/20

    摘要: A method is presented for evaluation of formation invasion and formation permeability by conducting a series of formation resistivity loggings in the operation of a measurement while drilling (MWD) logging system.

    摘要翻译: 提出了一种通过在钻井(MWD)测井系统进行测量操作中进行一系列地层电阻率测井来评估地层入侵和地层渗透率的方法。

    Mud turbine tachometer
    15.
    发明授权
    Mud turbine tachometer 失效
    泥浆涡轮转速计

    公开(公告)号:US4647853A

    公开(公告)日:1987-03-03

    申请号:US537821

    申请日:1983-09-30

    申请人: Martin E. Cobern

    发明人: Martin E. Cobern

    CPC分类号: G01P3/487 E21B47/00

    摘要: In an MWD measurement system, the speed of rotation of a downhole turbine is measured by the interaction of a triaxial magnetometer in a sensor package and a permanent magnet attached to the turbine shaft. The triaxial magnetometer may be part of an existing MWD system for measuring borehole directional parameters. The magnet is a strong magnet mounted on the turbine shaft perpendicular to the axis of the turbine and the axis of the drill string.

    摘要翻译: 在MWD测量系统中,通过传感器封装中的三轴磁力计与附接到涡轮轴的永磁体的相互作用来测量井下涡轮机的转速。 三轴磁力计可以是用于测量井眼方向参数的现有MWD系统的一部分。 磁体是安装在涡轮机轴上的强磁体,其垂直于涡轮机的轴线和钻柱的轴线。