Sliding sleeve with switchable layered fracturing cementing and its construction method

Abstract

A switchable well cementation sliding sleeve based on fracturing of separate layers comprises an outer barrel, an upper joint and a lower joint are installed at the upper end and the lower end of the barrel respectively, a fracturing port is formed in the side wall of the upper portion of the outer barrel, and an upper center pipe, an upper connection sleeve, a lower center pipe and a lower connection sleeve are installed inside the outer barrel. The switchable well cementation sliding sleeve based on fracturing of the separate layers is not provided with a ball seat, so a full bore of the inner wall can be maintained, fracturing fluid can flow back in time, and the construction period is shortened. The well cementation sliding sleeve is set in the upper center pipe through a bottom packer, downward pushing force big enough can be generated in the process of annular or continuous tubing pressing, so the upper center pipe can overcome shearing force of corresponding shearing dowels and move downwards, and therefore the fracturing port of the well cementation sliding sleeve can be opened.

Description

technical field [0001] The invention relates to a downhole tool for oil and gas wells, in particular to a switchable layered fracturing and cementing sliding sleeve for fracturing reconstruction of oil and gas wells and a construction method thereof. Background technique [0002] In the development process of horizontal wells, a variety of stimulation methods have been formed. The cementing sleeve staged fracturing and acidizing technology is one of them, and has achieved good results in practical applications. It has become a horizontal well staged fracturing technology One of the latest trends in cracking. At present, there are mainly two types of cementing sleeves at home and abroad. [0003] The first is to open the cementing sliding sleeve by stepping balls and perform staged fracturing operations. After the fracturing operation is completed, the ball seat can be retained or drilled out according to production needs. The disadvantage of this cementing sleeve is that t...

AI Technical Summary

Problems solved by technology

The disadvantage of this cementing sleeve is that the full diameter of the wellbore cannot be guaranteed after the fracturing is completed. To maintain the full diameter, additional drilling is required to remove the ball seat, which increases the workload

[0004] The opening and closing of the second type of cementing sliding sleeve is realized by a special switch tool. Although the cementing sliding sleeve ensures the full diameter of the wellbore, it needs to be closed in time after the fracturing of this layer is completed to achieve interlayer isolation. The transformation of the next layer can only be started after the sleeve is installed, and finally the sliding sleeve is selectively opened for production, which increases the workload

At the same time, due to the limitation of the lifting capacity of the operating equipment and the signal display requirements for the opening of the sliding sleeve, it is sometimes difficult to open and close the sliding sleeve

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