Mechanical underground sleeve valve

Abstract

The invention discloses a mechanical underground sleeve valve comprising a valve body, a switch tool, a protecting sliding sleeve and a valve plate. The valve body comprises an upper joint, a valve seat joint, a connection sleeve, a valve seat and a lower joint. The valve plate is hinged onto the valve seat, the protecting sliding sleeve is mounted in the valve body, the outer wall of the protecting sliding sleeve matches with the inner wall of the valve seat joint and the inner wall of the valve seat at the same time, and the lower end face of the protecting sliding sleeve is disposed on a step of the lower joint, a positioning lock is mounted on the inner wall of the connection sleeve, and a positioning groove matching with the positioning lock is mounted on the outer wall of the protecting sliding sleeve. The protecting sliding sleeve is arranged in the valve body, a conventional well cementation technology can be adopted for well cementation work, and working difficulty is reduced. An externally embedded switch sliding sleeve is adopted to be fixedly connected with a drilling tool in a shearing manner, so that during the whole process of placing the switch tool into a well, the risk of early failure of the valve resulted from that a drilling head is scrapped and elements and mechanisms in the sleeve valve are worn out is avoided.

Description

[0001] technical field [0002] The invention relates to the technical field of oil and gas drilling downhole tools, and is mainly used in underbalanced drilling and well completion construction operations. Background technique [0003] During the process of underbalanced drilling, since the drilling fluid column pressure is lower than the reservoir fluid pressure, the drilling fluid will not infiltrate and pollute the reservoir, thus maximizing the protection of the reservoir and effectively increasing the single well production. At the same time, in the process of underbalanced operation, because the pressure of the drilling fluid column cannot balance the pressure of the reservoir fluid, there is a certain pressure in the wellbore. Therefore, when the drill string is lifted to the upper part of the wellbore during the tripping process, the weight of the drill string is insufficient. The drill string will be pushed out of the wellhead when it overcomes the upward force gen...

AI Technical Summary

Problems solved by technology

[0008] The purpose of the present invention is to solve the problem that the existing hydraulic casing valve technology cannot get rid of the limitation of ground hydraulic control, while the foreign mechanical casing valve has complex structure, low reliability, and the drill bit is easy to scrape the inner wall of the valve body and easily get stuck, resulting in A series of technical problems such as the inability of the operating tool to effectively open or close the casing valve and the difficulty in cementing provide a mechanical casing valve with a simple structure and easy operation. A protective sleeve, which can keep the valve plate open and protect the valve core when conventional cementing methods are used; at the same time, the switch tool matched with the casing valve is connected externally with shear screws The structure of the switch sliding sleeve can effectively solve the problem of the drill bit scraping the valve body and the valve plate stuck during the operation, and adopts the multi-layer shear screw structure design to improve the reliability of the tool operation

Images