Double-acting one-way valve

Abstract

The utility model discloses a double-acting one-way valve which comprises an upper cylinder body, a pin seat is installed in the upper cylinder body, and a valve rod is installed in the pin seat. The middle barrel body is in threaded connection with the upper barrel body, and a first one-way valve is mounted between the middle barrel body and the pin seat; the lower cylinder body is in threaded connection with the middle cylinder body, and a second one-way valve is mounted between the lower cylinder body and the middle cylinder body; the lower end of the upper cylinder sleeves the upper end of the middle cylinder, and the lower end of the middle cylinder sleeves the upper end of the lower cylinder; a sealing face matched with a pitching ball is arranged at the upper end of the valve rod, overflowing holes are formed in the front end of the valve rod in the circumferential direction, and a center flow channel is formed in the valve rod in the axial direction. The one-way valve is applied to a drainage gas recovery system, keeps one-way flow of fluid, prevents gas or liquid from flowing backwards, and improves efficiency and safety of the system.

Description

Technical Field

[0001] The utility model belongs to the technical field of drilling operations, and particularly relates to a double-acting check valve. Background Art

[0002] The existing check valve uses a rupture disk structure to control the wellbore pressure. The tool string will carry more than ten rupture disks. During use, it is necessary to apply pressure to break the rupture disk so that the liquid in the tool can flow reversely. The overall structure of the tool is complex, and operation and maintenance are inconvenient. Content of the Utility Model

[0003] The utility model provides a double-acting check valve, aiming to solve the existing problems.

[0004] The utility model is realized as follows. A double-acting check valve includes:

[0005] An upper cylinder body, in which a pin seat is installed, and a valve stem is installed in the pin seat;

[0006] An intermediate cylinder body, which is threadedly connected to the upper cylinder body, and a first check valve is installed between the intermediate cylinder body and the pin seat;

[0007] A lower cylinder body, which is threadedly connected to the intermediate cylinder body, and a second check valve is installed between the lower cylinder body and the intermediate cylinder body;

[0008] The lower end of the upper cylinder body is sleeved on the upper end of the intermediate cylinder body, and the lower end of the intermediate cylinder body is sleeved on the upper end of the lower cylinder body;

[0009] The upper end of the valve stem is provided with a sealing surface adapted to the ball, and flow holes are circumferentially arranged on the front end of the valve stem, and a central flow channel is axially arranged in the valve stem.

[0010] In some embodiments, the first check valve and the second check valve have the same structure and are arranged back to back.

[0011] In some embodiments, the first check valve includes a valve seat, a valve body and a valve plate. The valve plate and the valve body are hinged, and a sealing member is arranged between the valve seat and the valve body.

[0012] In some embodiments, a pin hole is arranged on the outer wall of the front end of the valve stem.

[0013] In some embodiments, when the valve stem is in the first position, the lower end of the pin seat is fixedly connected to the upper end of the valve stem through a shear pin, the valve stem penetrates through the first check valve, and the first check valve is opened while the second check valve is closed.

[0014] In some embodiments, when the valve stem is in the second position, the shear pin breaks due to the shear force, the pin seat is separated from the valve stem, the valve stem penetrates through the second check valve, and the first check valve is closed while the second check valve is opened.

[0015] In some embodiments, an overflow groove is provided on the inner wall of the upper end of the intermediate cylinder body. When the valve stem is in the second position, the overflow hole communicates with the overflow groove.

[0016] In some embodiments, the overflow hole is arranged at the rear side of the sealing surface.

[0017] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0018] The present utility model discloses a double-acting check valve, which is applied to a drainage gas production system to maintain the unidirectional flow of fluid, prevent the backflow of gas or liquid, and improve the efficiency and safety of the system; this structure adopts a ball-throwing structure, simplifies the structure and operation process of the check valve, and improves the use reliability; using a double-acting check valve for drainage gas production is equivalent to carrying more than a dozen rupture discs, reducing the overall operation time, making the structure more reliable, and reducing the well control risk to be lower and safer. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic structural diagram of the present utility model;

[0020] Figure 2 is an embodiment diagram of the present utility model;

[0021] Figure 3 is Figure 1 an enlarged view of part A in

[0022] Figure 4 is Figure 2 an enlarged view of part B in

[0023] In the figure: 1 - upper cylinder body, 2 - pin seat, 3 - shear pin, 4 - valve body, 5 - valve plate, 6 - seal, 7 - valve seat, 8 - intermediate cylinder body, 9 - return spring, 10 - overflow groove, 11 - overflow hole, 12 - central flow channel, 13 - lower cylinder body, 14 - ball. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] In order to make the objectives, technical solutions and advantages of the present utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.

[0025] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model. In addition, in the description of the present utility model, the meaning of "a plurality of" is two or more unless otherwise specifically defined.

[0026] Please refer to Figures 1-4 , the present utility model provides a technical solution: a double-acting check valve, comprising: an upper cylinder body 1, an intermediate cylinder body 8, and a lower cylinder body 13.

[0027] A pin seat 2 is installed in the upper cylinder body 1, and a valve stem is installed in the pin seat 2; the intermediate cylinder body 8 is threadedly connected to the upper cylinder body 1, and a first check valve is installed between the intermediate cylinder body 8 and the pin seat 2; the lower cylinder body 13 is threadedly connected to the intermediate cylinder body 8, and a second check valve is installed between the lower cylinder body 13 and the intermediate cylinder body 8; the lower end of the upper cylinder body 1 is sleeved on the upper end of the intermediate cylinder body 8, and the lower end of the intermediate cylinder body 8 is sleeved on the upper end of the lower cylinder body 13;

[0028] The upper end of the valve stem is provided with a sealing surface adapted to the ball 14, the circumferential direction of the front end of the valve stem is provided with a flow hole 11, and a central flow channel 12 is axially opened in the valve stem.

[0029] Among them, the first check valve and the second check valve have the same structure and are arranged back to back; the check valve includes a valve seat 7, a valve body 4, and a valve plate 5. The valve plate 5 and the valve body 4 are hinged, and a return torsion spring is arranged between the valve plate 5 and the valve body 4; a sealing member 6 is arranged between the valve seat 7 and the valve body 4;

[0030] When the valve stem is in the first position, the lower end of the pin seat 2 is fixedly connected to the upper end of the valve stem through a shear pin 3, the valve stem penetrates through the first check valve, and the first check valve is opened while the second check valve is closed.

[0031] When the valve stem is in the second position, the shear pin 3 breaks due to the shear force, the pin seat 2 is separated from the valve stem, the valve stem penetrates through the second check valve, the first check valve is closed, and the second check valve is opened.

[0032] Specifically, an overflow groove 10 is opened on the inner wall of the upper end of the intermediate cylinder body 8. When the valve stem is in the second position, the flow hole 11 is communicated with the overflow groove 10; a pin hole is provided on the outer wall of the front end of the valve stem; the flow hole 11 is arranged behind the sealing surface.

[0033] Such as Figure 1As shown, when the double-acting one-way valve is in the standby state, the valve stem is fixed in the inner cavities of the pin seat 2 and the intermediate cylinder body 8 through the shear pin 3. At this time, the valve stem penetrates through the first one-way valve, the first one-way valve is normally open, and the second one-way valve can only pass downward;

[0034] As Figure 2 shown, when the double-acting one-way valve needs to work, the ball 14 is dropped from the pipe string. The ball 14 reaches the designated position of the valve stem through the channel in the pipe string. At this time, pressure is applied to the inside of the pipe string from the wellhead, the pressure inside the pipe string increases, an annular sealing surface is formed between the ball 14 and the valve stem, and the pressure inside the pipe string creates a radial shearing force on the shear pin 3.

[0035] When the pressure inside the pipe string increases to the preset working pressure of the double-acting one-way valve, the shear pin 3 is cut off, and the valve stem moves downward under the action of the pressure to reach the designated position and is in the inner cavities of the intermediate cylinder body 8 and the lower cylinder body 13; the pin seat 2 is separated from the valve stem, the upper end of the valve stem disengages from the first one-way valve, the valve plate 5 of the first one-way valve is reset by the return spring 9, the lower end of the valve stem pushes open the second one-way valve, the first one-way valve can only pass upward, and the second one-way valve is normally open.

[0036] At this time, due to the change in the position of the valve stem, the double-acting one-way valve changes from the state of passing only downward to the state of passing only upward, realizing the function of the double-acting one-way valve.

[0037] When the double-acting one-way valve completes the commutation work, there is still an annular sealing surface between the ball 14 and the valve stem. As the water level of the underground permeating water gradually rises and the gas production pressure gradually increases, the underground permeating water and gas enter the double-acting one-way valve through the pipe string, flow into the flow groove 10 of the intermediate cylinder body 8 through the central flow channel 12 and the flow hole 11 of the valve stem, and then enter the upper cylinder body 1, finally realizing drainage and gas production.

[0038] The above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A double-acting one-way valve, characterized in that: include: An upper cylinder, wherein a pin seat is installed in the upper cylinder, and a valve stem is installed in the pin seat; The middle cylinder is threadedly connected to the upper cylinder, and a first one-way valve is installed between the middle cylinder and the pin seat; The lower cylinder is threadedly connected to the middle cylinder, and a second one-way valve is installed between the lower cylinder and the middle cylinder; The lower end of the upper cylinder is sleeved on the upper end of the middle cylinder, and the lower end of the middle cylinder is sleeved on the upper end of the lower cylinder; The upper end of the valve stem is provided with a sealing surface adapted to the pitching ball, the front end of the valve stem is provided with a flow hole in the circumferential direction, and the valve stem is provided with a central flow channel in the axial direction.

2. A double-acting one-way valve according to claim 1, characterized in that: The first one-way valve and the second one-way valve have the same structure and are arranged opposite to each other.

3. A double-acting one-way valve according to claim 1, characterized in that: The first one-way valve comprises a valve seat, a valve body and a valve plate. The valve plate and the valve body are hinged, and a sealing member is arranged between the valve seat and the valve body.

4. A double-acting one-way valve according to claim 1, characterized in that: The outer wall at the front end of the valve stem is provided with a pin hole.

5. A double-acting one-way valve according to claim 4, characterized in that: When the valve stem is in the first position, the lower end of the pin seat is fixedly connected to the upper end of the valve stem through the shear pin, and the valve stem passes through the first one-way valve, the first one-way valve is opened, and the second one-way valve is closed.

6. A double-acting one-way valve according to claim 4, characterized in that: When the valve stem is in the second position, the shear pin breaks due to the shear force, the pin seat is separated from the valve stem, the valve stem passes through the second one-way valve, the first one-way valve is closed, and the second one-way valve is opened.

7. A double-acting one-way valve according to claim 6, characterized in that: The inner wall of the upper end of the intermediate cylinder is provided with a flow groove, and when the valve stem is in the second position, the flow hole is communicated with the flow groove.

8. A double-acting one-way valve according to claim 1, characterized in that: The flow hole is arranged at the rear side of the sealing surface.

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