Novel double-seal arrow-shaped check valve

Abstract

The invention relates to a novel double-seal arrow-shaped check valve, is mainly used for an anti-spraying device in an oilfield drill column and belongs to the field of well control equipment of a petroleum and gas drilling well. The novel double-seal arrow-shaped check valve comprises an upper valve body, a lower valve body, an arrow-shaped valve core, a supporting base, a rubber cylinder, a thrust block, a spring and a valve core rear part rod, wherein the upper valve body is connected with the lower valve body through a thread; the inner part of the upper valve body is designed with a tapered surface; the tapered surface and a tapered face of the arrow-shaped valve core are contacted to form a seal; the lower valve body is internally provided with the supporting base and the rubber cylinder, the thrust block and the spring are sleeved in the rear part of the arrow-shaped valve core; the valve core rear part rod and the supporting base are clamped through a safe clamping ring; and drilling-down liquid and well drilling liquid do not block a channel in a normal circulation process. The novel double-seal arrow-shaped check valve has the advantages of simple structure, smooth flow channel, small drilling-down resistance and a well drilling medium can smoothly pass through; and at a high pressure, the novel double-seal arrow-shaped check valve has a double-sealing effect, can prevent underground fluid from upwards flowing and is good for well control work.

Description

technical field [0001] The invention relates to a novel double-sealed arrow-shaped check valve, which is mainly used in blowout prevention devices in drill strings in oil fields, and belongs to the field of oil and gas drilling well control equipment. Background technique [0002] Due to the complex and changeable formations, high-pressure fluids are often encountered during the drilling process. If there is no reliable blowout prevention system, well kicks or blowouts may occur, which will affect the safety of drilling operations and drilling efficiency. At present, blowout preventers of various types and specifications have the ability to control well kick or blowout outside the drill string, but the blowout prevention technology inside the drill string needs to be further improved. The arrow-shaped check valve is connected in the drill string as a blowout prevention tool in the drill string. When encountering high-pressure oil and gas layers, it can drive the arrow-shaped...

AI Technical Summary

Problems solved by technology

In the prior art, the main components of the arrow-shaped check valve are the valve body, and there are parts such as a pressure cap and a valve seat in the valve body. , The gap between the valve seat and the inside of the valve body needs to be sealed by rubber parts

The existence of the pressure cap restricts the passage of the drilling medium, resulting in resistance, and the rubber parts used for sealing are easy to fail and fall off under the action of high-pressure and high-speed fluid, which affects the sealing effect of the arrow-shaped valve core; The valve seat is in a contact state, and is affected by the upward buoyancy during the downhole process. The valve core often seals the valve seat, so that the water hole of the drilling tool is closed when the drill is run in. This not only affects the speed of the drill pipe, but also is unfavorable to the well control operation; The spring under the spool of the existing arrow-shaped check valve also fails under pressure and protection

[0003] At present, the existing arrow-shaped check valve only has a primary seal formed by the arrow-shaped valve core and the valve seat, and the main sealing surface is easily eroded and worn, and the sealing reliability is insufficient.

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