发明名称 |
FREMGANGSMAATE OG APPARAT FOR BESTEMMELSE AV DYBDEN AV ET VERKTOEY ELLER EN SONDE |
摘要 |
<p>A high resolution method and apparatus for measuring the depth of a tool suspended from a cable inside a borehole are described. The tool includes accelerometers for measuring its acceleration and this measurement is combined with a cable depth measurement with which the amount of cable in the borehole is determined. A Kalman filter is employed to continually provide estimates of the velocity and depth of the tool from the accelerometer and cable depth measurements. A filter modifier alters operation of the filter during discontinuous motions of the tool such as when it is stuck and slips. A tool sticking detector senses when the tool is stuck and for how long to correspondingly modify the filter by forcing it to more strongly rely upon accelerometer measurements when the tool is stuck and gradually return to normal filter operation when the tool resumes movement after having been stuck.</p> |
申请公布号 |
NO833813(A) |
申请公布日期 |
1984.04.30 |
申请号 |
NO19830003813 |
申请日期 |
1983.10.19 |
申请人 |
SCHLUMBERGER LTD |
发明人 |
CHAN DAVID |
分类号 |
E21B47/04;G01B7/26;(IPC1-7):E21B/ |
主分类号 |
E21B47/04 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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