Adjacent well distance while-drilling electromagnetic large-range detection system without interfering adjacent well operation

Abstract

The invention provides an adjacent well distance while-drilling electromagnetic large-range detection system without interfering adjacent well operation. The adjacent well distance while-drilling electromagnetic large-range detection system comprises an adjacent well signal transmitting module, a positive drilling signal receiving module and a ground signal processing module, wherein the adjacentwell signal transmitting module comprises adjacent well sleeves, insulating joints and a low-frequency alternating current power supply; the insulating joints are mounted in the middles of the adjacent well sleeves and spaced from the adjacent well sleeves; the ground surface low-frequency alternating current power supply supplies power to the two parts of the adjacent well sleeves at the two endsof the insulating joints; the positive drilling signal receiving module comprises a non-magnetic drill rod and an MWD, and the MWD detects magnetic field signals generated by current on the adjacentwell sleeves; and the ground signal processing module comprises an MWD signal detecting device and a computer, the MWD signal detecting device receives the magnetic field signals and transmits the magnetic field signals to the computer, and the computer is used for calculating the distance between an adjacent well and a positive drilling well through the magnetic field signals. The adjacent well distance while-drilling electromagnetic large-range detection system has the beneficial effects that in the drilling process, the adjacent well distance is detected while drilling, normal operation ofthe adjacent well is not interfered, the production efficiency is improved, and the detection precision is improved.

Description

technical field [0001] The invention relates to the technical field of oil, natural gas and coalbed methane drilling and production engineering, in particular to an electromagnetic large-range detection system for the distance between adjacent wells while drilling without interfering with the operation of adjacent wells. Background technique [0002] In the exploitation of oil and gas resources and coalbed methane, complex wells such as cluster wells, connecting wells and double horizontal wells are widely used in the petroleum and geological fields in order to improve the recovery rate. However, the wellbore trajectories of these wells with complex structures are complex, and the distance between adjacent wells needs to be detected accurately while drilling. Measurement while drilling can monitor the drilling position while drilling. However, as the well depth increases, the position of the drilling well monitored by measurement while drilling will have a large deviation fr...

AI Technical Summary

Problems solved by technology

However, the wellbore trajectories of these complex-structured wells are complex, and it is necessary to accurately detect the distance between adjacent wells while drilling

Measurement while drilling can monitor the drilling position while drilling. However, as the well depth increases, the position of the drilling well monitored by measurement while drilling will have a large deviation from the actual position due to the accumulation of errors. The distance between the well being drilled and the offset well is inaccurate

Using electromagnetic technology to detect the distance of adjacent wells is a feasible method. Among the current detection methods based on electromagnetic technology, WellSpot, MGT, RMRS and SWG all need to run electromagnetic source or signal receiving probes in adjacent wells, which will interfere with adjacent wells. normal operation, seriously reducing production efficiency

However, the signal of the surface current injection method decreases significantly with the increase of depth, especially when the formation resistivity is low, the signal attenuates quickly, which leads to a decrease in detection distance and accuracy

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