Determining the pressure of formation fluid in earth formations surrounding a borehole
    1.
    发明授权
    Determining the pressure of formation fluid in earth formations surrounding a borehole 有权
    确定井眼周围地层中地层流体的压力

    公开(公告)号:US07178392B2

    公开(公告)日:2007-02-20

    申请号:US10644284

    申请日:2003-08-20

    IPC分类号: E21B47/06

    CPC分类号: E21B49/10 E21B49/008

    摘要: A method for determining formation fluid pressure in earth formation surrounding a borehole wall uses a downhole probe coupled to a variable-volume cavity. The probe is driven into contact with formation at the borehole wall. The method includes expanding the volume of the cavity during a first period of time to establish fluid communication between tool fluid and formation fluid, by withdrawing a minimal amount of fluid from the formation. During a second period of time the tool pressure is allowed to equilibrate to formation pressure. When pressure equilibrium is established, formation fluid pressure is set equal to tool pressure. A preferred embodiment includes terminating expanding the volume of the cavity on detecting a break in the mud cake seal. An associated formation pressure tester tool includes an elongated body; a probe defining a formation fluid inflow aperture, an electromechanical assembly defining a variable-volume cavity, a pretest flow line coupling the aperture to the cavity, a pressure sensor coupled to the cavity; and downhole electronic means for controlling the expansion of the volume of the cavity.

    摘要翻译: 用于确定围绕井壁的地层中的地层流体压力的方法使用连接到可变体积腔的井下探针。 探头被驱动与钻孔壁的形成接触。 该方法包括在第一时间段内膨胀空腔的体积,以通过从地层中抽取最少量的流体来建立工具流体和地层流体之间的流体连通。 在第二时间段期间,允许工具压力平衡到地层压力。 当建立压力平衡时,地层流体压力设定为等于工具压力。 优选实施例包括在检测到泥饼密封件中的断裂时终止膨胀空腔的体积。 相关联的地层压力测试仪工具包括细长体; 限定地层流体流入孔的探针,限定可变体积腔的机电组件,将孔耦合到空腔的预测流线,耦合到空腔的压力传感器; 以及井下电子装置,用于控制空腔体积的膨胀。

    Determining the pressure of formation fluid in earth formations surrounding a borehole
    2.
    发明申请
    Determining the pressure of formation fluid in earth formations surrounding a borehole 有权
    确定井眼周围地层中地层流体的压力

    公开(公告)号:US20050039527A1

    公开(公告)日:2005-02-24

    申请号:US10644284

    申请日:2003-08-20

    IPC分类号: E21B49/00 E21B49/10 E21B47/06

    CPC分类号: E21B49/10 E21B49/008

    摘要: A method for determining formation fluid pressure in earth formation surrounding a borehole wall uses a downhole probe coupled to a variable-volume cavity. The probe is driven into contact with formation at the borehole wall. The method includes expanding the volume of the cavity during a first period of time to establish fluid communication between tool fluid and formation fluid, by withdrawing a minimal amount of fluid from the formation. During a second period of time the tool pressure is allowed to equilibrate to formation pressure. When pressure equilibrium is established, formation fluid pressure is set equal to tool pressure. A preferred embodiment includes terminating expanding the volume of the cavity on detecting a break in the mud cake seal. An associated formation pressure tester tool includes an elongated body; a probe defining a formation fluid inflow aperture, an electromechanical assembly defining a variable-volume cavity, a pretest flow line coupling the aperture to the cavity, a pressure sensor coupled to the cavity; and downhole electronic means for controlling the expansion of the volume of the cavity.

    摘要翻译: 用于确定围绕井壁的地层中的地层流体压力的方法使用连接到可变体积腔的井下探针。 探头被驱动与钻孔壁的形成接触。 该方法包括在第一时间段内膨胀空腔的体积,以通过从地层中抽取最少量的流体来建立工具流体和地层流体之间的流体连通。 在第二时间段期间,允许工具压力平衡到地层压力。 当建立压力平衡时,地层流体压力设定为等于工具压力。 优选实施例包括在检测到泥饼密封件中的断裂时终止膨胀空腔的体积。 相关联的地层压力测试仪工具包括细长体; 限定地层流体流入孔的探针,限定可变体积腔的机电组件,将孔耦合到空腔的预测流线,耦合到空腔的压力传感器; 以及井下电子装置,用于控制空腔体积的膨胀。