Casing cementing mechanical sliding sleeve and special switch device thereof

Abstract

The invention discloses a casing cementing mechanical sliding sleeve and a special switch device thereof. The casing cementing mechanical sliding sleeve comprises a first upper hollow connector and a first lower hollow connector, wherein a working oil port communicated with an external oil layer is formed in the first upper hollow connector; a sliding sleeve which can open and close the working oil port is mounted in the first upper hollow connector and the second lower hollow connector. The special switch device comprises a hollow center tube; the outsides of the upper and lower end of the center tube are respectively sleeved with piston cylinders; a countersunk groove is formed in a position, positioned between the two piston cylinders, on the outer wall of the center tube; a clamping device which can radially move and is matched with a preserved groove in the sliding sleeve is mounted in the countersunk groove. When a special switch is downwards pressed, a positioning detent extends out of a position between the two piston cylinders, is clamped in the preserved groove in the sliding sleeve and drives the sliding sleeve to downwards move; when a spring pawl is clamped in a lower clamping groove, the working oil port is opened, so the remining of the oil layer becomes possible.

Description

technical field [0001] The invention relates to a cementing mechanical sliding sleeve and a special switch device thereof, belonging to the technical field of petroleum machinery. Background technique [0002] The distribution and existence state of underground crude oil are complex and changeable, and the multi-reservoir bubble-like distribution is common. After the oil well is drilled, the casing is run, and the casing becomes the main channel connecting multiple oil reservoirs. The casing and each oil reservoir are blocked by cementing, and then the casing is destroyed at the reservoir that needs to be collected. Connecting the reservoir, allowing crude oil to flow into the casing. [0003] After the preliminary work is completed, the oil reservoir to be collected is determined. The traditional method is to use special perforating charges to penetrate several holes at the depth of the casing corresponding to the oil layer, and the fracturing operation vehicle performs fr...

AI Technical Summary

Problems solved by technology

[0004] The traditional perforation technology has many disadvantages, such as affecting the life of the casing, polluting the oil layer, complex construction technology, high construction cost, etc., and it is necessary to exploit multiple oil layers in order from deep to shallow, which is not flexible enough for development and adjustment.

When it is necessary to return to other oil layers after the collection of a single oil layer, the perforation position must be blocked with cement. After the plugging, it will not be possible to open it again to collect and re-migrate crude oil, which will affect the production efficiency of the oil well.

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