Preset casing pipe segmented valve type staged fracturing method and special tool thereof

Abstract

The invention discloses a preset casing pipe segmented valve type staged fracturing method and a special tool thereof, and relates to the technical field of petroleum drilling. The method comprises the following steps that () a casing pipe with a toe end sliding sleeve and a plurality of casing pipe segmented valves preset is fed into a shaft; 2) the casing pipe is divided into a first section to an N section which are continuous through the toe end sliding sleeve and the casing pipe segmented valves; 3) the toe end sliding sleeve is opened, and then fracturing construction is carried out on the first section; 4) packing and perforation are achieved on the second section to the N section through a well entering tool string assembly, and then the well entering tool string assembly is taken out for fracturing construction; and 5) after fracturing construction of the first section to the N section is completed, a coiled tubing is fed to drill and grind off valve plates on the casing pipe segmented valves of all the sections, and subsequent oil and gas production is facilitated. The segmented tool is the casing pipe segmented valves, the outer diameter of the well entering tool string assembly is far smaller than that of a bridge plug, when the casing pipe deforms, the well entering tool string assembly can enter a well normally, and the pumping bridge plug is likely to meet resistance and cannot enter the well.

Description

technical field [0001] The present invention relates to the technical field of petroleum drilling, and more specifically relates to the technical field of a preset casing segmented valve-type segmental fracturing method. Background technique [0002] Currently, staged fracturing technology is mainly used for reservoir stimulation in the petroleum industry. Among them, the technology of staged fracturing and selected firing holes for horizontal well cable transmission is a commonly used oilfield stimulation measure, especially suitable for the development of gas reservoirs and fractured reservoirs. Its working principle is as follows: the locator, multiple perforating guns and composite bridge plugs are connected in series, and electric transmission type perforation + composite bridge plugs are used for joint construction. The guns and bridge plugs are transported to the target layer. After the bridge plugs are sealed, the power is lifted up and positioned step by step at pre...

AI Technical Summary

Problems solved by technology

[0003] However, when this technology faces the problem of downhole casing deformation, it is limited by the fact that the outer diameter of the bridge plug is too large to pass through the deformation of the downhole casing, and the entire tool string cannot reach the predetermined position downhole to carry out the plug setting operation. The perforating bridge is sent to perforate and then pressed together, which greatly reduces the implementation efficiency and operability of the process

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