Multi-joint intensive grouting well-reinforcing method for reinforcing coal-bed gas well penetrating through goaf

Abstract

The invention belongs to the technical field of coal-bed gas exploitation and provides a multi-joint intensive grouting well-reinforcing method for reinforcing a coal-bed gas well penetrating through a goaf. According to the method, the problems that during passing-through of the goaf, the third spud-in well-drilling construction process is complex, and the stability of a third spud-in well body structure is poor are solved. The third spud-in drilling construction process is adopted; a well body of the coal-bed gas well is composed of a first spud-in drilled hole, a surface casing, a second spud-in drilled hole, an intermediate casing and a third spud-in drilled hole; when third spud-in drilling is constructed, multi-joint grouting reinforcing is conducted on well wall surrounding rock outside the intermediate casing, so that the strength of the well wall surrounding rock is improved, long-term stability of the coal-bed gas well is guaranteed, and the stabilized intermediate casing is directly used as the production casing of the coal-bed gas well. A multi-joint cement paste wrapped body supporting structure is formed between the intermediate casing and the well wall surrounding rock, the long-term stability of the well wall surrounding rock of the coal-bed gas well and the well body structure can be strengthened greatly.

Description

technical field [0001] The invention belongs to the technical field of coalbed methane exploitation, and in particular relates to a coalbed methane well cementing method for multi-node intensive grouting in goafs, which is used for reinforcement grouting and cementing construction of well wall surrounding rocks of coalbed methane wells. Background technique [0002] Due to the long service life of coalbed methane wells, it is necessary to maintain the stability and safety of the production wells within the service life, especially when coalbed methane wells pass through the goaf, affected by the residual deformation of the old goaf and the disturbance of the new mining area, it will CBM wells cause damage or destruction. In engineering practice, the control method often adopted is to nest multi-layer casings and reinforce them by grouting to realize the cementing construction of coalbed methane wells. For example, the well body structure and construction process of a typica...

AI Technical Summary

Problems solved by technology

[0007] In order to solve the problems of complex three-cut drilling construction technology and poor structural stability of the three-cut well body when crossing the goaf, the present invention further provides a cementing method for multi-node intensive grouting through the goaf to strengthen coalbed methane wells method

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