Down hole tool for determination of formation properties
    21.
    发明授权
    Down hole tool for determination of formation properties 失效
    用于测定地层特性的井下工具

    公开(公告)号:US4860581A

    公开(公告)日:1989-08-29

    申请号:US248867

    申请日:1988-09-23

    IPC分类号: E21B49/00 E21B49/08 E21B49/10

    摘要: The apparatus of the present invention relates to a down hole tool capable of extraction of valid samples and making pressure measurements useful in calculating formation permeability. The tool incorporates the features of a staddle packing to allow formation fluid specimens to be taken at large flow rates without depressing the pressure below the formation fluid bubble point. When used in combination with a pressure probe the tool is used to obtain meaningful permeability readings in a larger radius area than previously permitted with known dsigns. Additionally, the apparatus of the present invention allows flow control during the creation of the pressure pulse which enhances extraction of valid samples and the permeability determination. The apparatus may be modularly constructed so that in a single descent of the tool, a pressure profile of the zone of interest can be made, a fluid analysis can be made at each station, multiple uncontaminated fluid samples can be withdrawn at pressures above the bubble point, local vertical and horizontal permeability measurements can be made at each station, a packer module can be set at a location dictated by previous measurements and a large scale pressure build up test can be performed.