发明名称 |
Standoff compensation for nuclear logging while drilling systems |
摘要 |
<p>A standoff compensation system is disclosed for use in an LWD system implementing gamma density and/or neutron porosity measurements. An acoustic transducer is provided to measure the standoff distance between the logging tool and the borehole wall. The present invention includes a downhole processor for determining a weighting factor for the density and/or porosity measurements based upon the measured standoff distance. The weighting factor can either be calculated by the downhole processor according to a predetermined weighting function, or can be retrieved from a pre-calculated look-up table in ROM. The processor then multiplies the weighting factor by the count data from the sensor to determine a weighted count value. The weighted count values are accumulated during an averaging period and normalized, so that a single normalized count value can be generated and either stored in downhole memory, used immediately, or transmitted by telemetry to the surface.</p> |
申请公布号 |
GB2288018(B) |
申请公布日期 |
1998.12.02 |
申请号 |
GB19950006455 |
申请日期 |
1995.03.29 |
申请人 |
* HALLIBURTON COMPANY;* HALLIBURTON ENERGY SERVICES, INC. |
发明人 |
WARD E * SCHULTZ;GORDON L * MOAKE |
分类号 |
E21B47/08;E21B47/12;E21B49/00;G01V5/08;(IPC1-7):G01V5/08 |
主分类号 |
E21B47/08 |
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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