Switch-type double sliding sleeve assembly for staged fracturing of horizontal wells

Abstract

The invention belongs to the field of petroleum exploration and development and particularly relates to a opening-and-closing type double-sliding-sleeve assembly for staged fracturing of a horizontal well. The opening-and-closing type double-sliding-sleeve assembly for staged fracturing of the horizontal well comprises a fracturing sliding sleeve and a screen pipe sliding sleeve. The bottom end of the fracturing sliding sleeve is connected with the top end of the screen pipe sliding sleeve through threads. The opening-and-closing type double-sliding-sleeve assembly for staged fracturing of the horizontal well has the advantages that the phenomenon that a supporting agent is poured back greatly, and the fracturing effect is influenced is avoided; the diameter inside the well-dwelling pipe column is large, and thus treatment in a later stage is convenient; the sliding sleeves can be closed or opened in the later stage to control production; multi-stage fracturing can be freely achieved.

Description

technical field [0001] The invention belongs to the field of petroleum exploration and development, and in particular relates to a switchable double sliding sleeve assembly for staged fracturing of horizontal wells. Background technique [0002] At present, in the staged reconstruction of horizontal wells, it is necessary to use sliding sleeve switch tools. The currently used fracturing sleeves include differential pressure sleeves and ball-pitched sleeves. The principle of the differential pressure sliding sleeve is to open through the pressure difference of the inner sliding sleeve. During use, the problem that the differential pressure sliding sleeve is opened in advance or not fully opened often occurs. In the construction process of the ball-pitching sliding sleeve, it is often difficult to open the sliding sleeve, and the ball seat needs to be drilled and milled to ensure the diameter of the casing. After the completion of staged fracturing operations in ordinary hor...

AI Technical Summary

Problems solved by technology

In the construction process of the ball-pitching sliding sleeve, it is often difficult to open the sliding sleeve, and it is necessary to drill and mill the ball seat to ensure the diameter of the casing.

After the completion of staged fracturing operations in ordinary horizontal wells, the sliding sleeve remains open. Especially for shale gas production, proppant regurgitation occurs, and high-speed gas carries proppant output, resulting in damage to the wellhead bend

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