The tool gives out a current that travels around the casing before returning bacl to the electrode. Most of the current remains in the casing, but a small portion leaks into the formation. Electrodes present on the tool measures the voltage difference created by this leaked current, and this difference is directly proportional to the formation conductivity.
For better electrical contact between the tool and the casing essential for the measurements, small electrodes are designed on the body of the tool to make sure the scale and corrosion on the casing are cleaned.
The tool can be used to measure resistivity behind casing of sizes 5″ or 7″. This can be even used in wells upto 5000 meters, and it can be used in casing environment without any fluids or wells without fluid.
Application
- Formation Resistivity evaluation through cased hole
- Monitor Oil-Gas-Water contact.
- Evaluation of reservoir saturation
- Identification of gas zone.
- Monitor the water injection into the main zone.
- Re-evaluation of old fields to find missed oil or gas zones.
Specification |
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Max. Temperature
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310℉ (155℃)
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Max. Pressure
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15000 Psi (100 MPa)
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Tool O.D.
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3 1/2 in. (89 mm)
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Weight
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264 lb. (120 Kg)
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Logging Speed
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118 ft/h (36 m/h)
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Measurement Accuracy
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≤8%
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Vertical Resolution
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1.1m
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Investigation Depth
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2 m~10 m
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Working Frequency
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3Hz
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Measurable Formation Resistivity range
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1Ω·m~100 Ω·m
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