An expandable liner for refracturing and refracturing method

Abstract

The invention discloses an expansion liner tube for refracturing and a refracturing method. An expansion liner tube body is a hollow round tube, an expansion mandrel is arranged in the expansion linertube body, the expansion mandrel moves and carries out extrusion in the axial direction of the expansion liner tube body, after the expansion liner tube body is subjected to radial plastic deformation, the expansion liner tube body makes contact with a perforated sleeve, a new closed shaft is formed, and the closed shaft is used for refracturing. Compared with the existing refracturing technology, the expansion liner tube is adopted for refracturing, the expansion difficulty is reduced, the strength and the sealing performance of the liner tube after expansion are improved, meanwhile, the defect that a connector easily disengages is overcome, and the oil and gas yield can be increased by rebuilding the integrity of the shaft.

Description

technical field [0001] The invention relates to the technical field of oil and gas field development, in particular to an expandable liner for repeated fracturing and a repeated fracturing method. Background technique [0002] Low-permeability oil and gas reservoirs are crucial to the energy structure of my country and the world. The ultra-low porosity and ultra-low permeability characteristics of low-permeability reservoirs make it necessary to rely on hydraulic fracturing to realize industrial production. However, low-permeability reservoirs, especially shale gas wells, are prone to fracture failure due to the production process after hydraulic fracturing. Generally, the output can drop to half of the peak within half a year. As a more economical and efficient means, refracturing technology is being valued. [0003] A large number of studies at home and abroad have shown that refracturing is one of the effective measures to increase the production of real estate wells. ...

AI Technical Summary

Problems solved by technology

In areas where wells are densely distributed, fracturing fluid may also flow into adjacent wells, causing the natural pressure of the two wells to dissipate and produce fluid, and eventually be scrapped

[0005] In refracturing, rebuilding the integrity of the wellbore plays an important role. However, in the existing technology, there are defects such as difficult construction, low tool reliability, poor sealing performance, and easy detachment of joints when establishing a new wellbore.

Images