Anti-erosion and sand-free fracturing sleeve

Abstract

The invention provides an anti-erosion and no sand card fracturing sliding bush which can be connected with an oil pipe and arranged inside a bushing. The anti-erosion and no sand card fracturing sliding bush compromises a shell body. The upper end of the shell body is connected with an upper contact, and the lower end of the shell body is connected with a closed outer cylinder. A plurality of open holes is arranged on the circumferential direction of the closed outer cylinder. The outer shell is provided with a movable piston cylinder. The anti-erosion and no sand card fracturing sliding bush also compromises a sand blasting body. The upper end of the sand blasting body is stuck between the shell body and the piston cylinder. The upper end of the sand blasting body is connected with a lower contact. A nozzle is embedded inside the sand blasting body. The nozzle is provided with a plurality of bell shaped spray holes along the circumferential direction. The spray holes can be communicated with the open holes. The inside of the sand blasting is provided with sliding bush which is used for sealing the spray holes, and the sliding bush is connected with the lower contact detachably. The anti-erosion and no sand card fracturing sliding bush has the advantages of being capable of reducing casing damage during fracturing, and avoiding the sand card when lifting the pope, being thorough in back flushing, and high efficient in fracturing.

Description

technical field [0001] The invention relates to the technical field of oil and natural gas exploitation, and is a fracturing tool, in particular to an anti-erosion and sand-free fracturing sliding sleeve suitable for fracturing and exploiting oil and gas from vertical wells, highly inclined wells or horizontal wells. . Background technique [0002] In oil production, for oil reservoirs with abnormally high temperature, high pressure, low porosity and low permeability, the production wells are mainly well types such as highly deviated wells and horizontal wells, and staged fracturing must be carried out before production. It is a mechanical staged fracturing method, which can improve the conductivity of the reservoir, increase the output of the production well or the injection rate of the injection well, but it also has the following shortcomings: [0003] In the fracturing construction, the fracturing packer is forced to construct in sections. After the fracturing is comple...

AI Technical Summary

Problems solved by technology

[0003] In the fracturing construction, the fracturing packer is forced to construct in sections. After the fracturing is completed in one section, the ball is thrown to slip the sleeve, and the fracturing construction in the next section is carried out. If there are too many packers, the upper packer will be expanded repeatedly, which will affect the performance and sealing effect of the packer, which will easily cause fracturing failure. At the same time, shutting down the well after fracturing and blowout, because the wellhead pressure is low and the formation pressure is high. , the liquid flow from the formation to the wellhead will inevitably bring out part of the fracturing sand, making it easy to cause sand jams when the string is lifted up, resulting in overhaul accidents, difficult handling, long cycle, high labor intensity and poor safety

[0004] At the same time, in the fracturing construction, the casing will be inevitably damaged during the sand adding stage, which is mainly manifested in the following two aspects: 1. The ceramsite in the sand-carrying fluid passes through the sandblasting port at high speed, and under the action of inertia 2. The turbulence and turbulence generated around the sandblasting port cause the plowing of the ceramsite on the casing wall, so that the inner wall of the casing is facing Microscopic flaking around the blast port

[0005] Furthermore, after the fracturing is completed, the method of backwashing the well is usually used to clean the fracturing sand in the pipe string and the casing annulus, that is, the backwashing fluid is injected from top to bottom through the annulus for cleaning. After fracturing, the sandblasting ports of each fracturing stage have been opened, and the backwash fluid will enter the oil pipe from the sandblasting port of the fracturing stage above, so that the backwash liquid will take a shortcut and make the fracturing stage below The fracturing sand in the section cannot be washed, which increases the probability of sand sticking

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