发明名称 |
DETECTING SYSTEM AND METHOD FOR OIL OR GAS WELL |
摘要 |
A system for sensing the passage of a member past a predetermined location along a tubing disposed in an oil or gas well comprises: a magnet connected to the member, the magnet having a soft body so that the magnet can be drilled out by a drill bit lowered into the well after the member has passed the predetermined location; and a sensor, connected to the outside of the tubing at the predetermined location, for detecting a magnetic field of the magnet as the member with the magnet connected thereto passes the sensor. A method for assisting the proper placement of a cement slurry in an oil or gas well comprises: pumping a cement slurry through a tubing into an oil or gas well; releasing a cementing plug into the tubing in series with the cement slurry, the cementing plug having a magnet as referred to above; and sensing the cementing plug at a predetermined location along the tubing, including: generating a null signal in response to providing a biasing magnetic field in opposition to a magnetic field naturally occurring in the tubing at the predetermined location; and changing the null signal to an indicator signal in response to the magnet moving in the tubing to the predetermined location.
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申请公布号 |
CA2120109(A1) |
申请公布日期 |
1994.10.01 |
申请号 |
CA19942120109 |
申请日期 |
1994.03.28 |
申请人 |
HALLIBURTON COMPANY |
发明人 |
DAVIS, JAMES L.;VAN BERG, CHARLES F., JR. |
分类号 |
E21B47/09;(IPC1-7):G01B7/30 |
主分类号 |
E21B47/09 |
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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