Long-lasting anti-erosion float valve

Abstract

The application relates to the technical field of oil and gas exploitation, and aims to provide a long-acting anti-erosion float valve which comprises a hollow first valve body and a hollow second valve body which are connected through side supporting arms and internally provided with fluid channels, a valve plate is hingedly arranged on the side supporting arm of one end of the first valve body close to the second valve body, an elastic piece for resetting the valve plate to close the fluid channel on the first valve body is arranged at the valve plate, the fluid channel on the first valve body is obliquely arranged and forms an included angle alpha with the axis of the first valve body. The application can reduce the erosion of the valve plate and prolong the service life.

Description

TECHNICAL FIELD

[0001] The present application relates to the oil and gas technology field, and particularly relates to a long-acting anti-erosion float valve. BACKGROUND

[0002] The float valve is a key well control equipment for controlling the one-way flow of fluid in drilling, oil and gas exploitation and the like, and mainly functions to prevent the reverse flow of fluid (such as mud, oil and gas and the like) in the well to ensure the safety of operation. The core structure thereof usually comprises a valve body, a rotatable valve plate and an elastic element (such as a torsional spring). When the fluid such as mud flows in the forward direction, the fluid pressure pushes the valve plate to open the channel against the force of the elastic element to ensure normal circulation. If the reverse pressure increases due to well kick, pump stoppage and the like, the elastic element drives the valve plate to reset to close the channel to prevent backflow. The float valve is widely used in the drilling string, casing string and the like, and is an important device for preventing blowout and the like, and its performance is directly related to the safety and efficiency of drilling operation.

[0003] At present, the conventional float valve has obvious erosion phenomenon in the use process due to the long-term erosion of the valve plate by mud, which affects the service life of the float valve, and even causes the deformation of the valve plate and the like, resulting in the defect of loose closure when the valve plate resets. SUMMARY

[0004] The present application aims to provide a long-acting anti-erosion float valve capable of reducing the erosion of the valve plate and improving the overall service life.

[0005] To achieve the above-mentioned application purposes, the technical solution adopted by the present application is as follows: a long-acting anti-erosion float valve, comprising a hollow first valve body and a hollow second valve body, wherein the first valve body and the second valve body are connected through a side support arm, a valve plate is hingedly arranged on the side support arm of the first valve body close to the second valve body, and an elastic element for resetting the valve plate to close the fluid channel on the first valve body is arranged at the valve plate.

[0006] The fluid channel on the first valve body is inclined and forms an included angle a with the axis of the first valve body.

[0007] Preferably, the included angle a is 5-15°.

[0008] Preferably, the included angle a is 7°.

[0009] Preferably, the fluid channel on the first valve body is inclined to the side of the valve plate away from the hinged center along the fluid direction.

[0010] Preferably, the valve plate is sprayed with a hard alloy layer on the side opposite to the fluid channel on the first valve body.

[0011] Preferably, the valve plate is provided with a hinge lug on the side close to the hinge center, the side branch arm is provided with a hinge shaft at the position opposite to the hinge lug, and the valve plate and the hinge lug are sleeved on the hinge shaft to form a hinge; the elastic member is a return torsion spring, one leg of the return torsion spring is clamped on the back surface of the valve plate, and the other leg is fixed on the end of the first valve body.

[0012] Preferably, the first valve body is provided with a sealing step on the inner circumferential surface of the end close to the valve plate, and the sealing step is provided with an inner bushing and a sealing ring.

[0013] Preferably, the first valve body is provided with an end groove on the end surface opposite to the return torsion spring, the end groove is provided with an adjusting block capable of sliding along the length direction of the end groove, and the leg of the return torsion spring is inserted into the adjusting block.

[0014] The first valve body is provided with a side groove on the inner side wall of the fluid channel close to the end groove, the side groove is communicated with the end groove through a connecting pipe, the connecting pipe is provided with a moving plunger in sliding fit with the connecting pipe, and one end of the moving plunger is connected with the adjusting block through a connecting rod.

[0015] Preferably, the side groove is provided with a pressure bag, and the pressure bag is communicated with the connecting pipe.

[0016] Preferably, the side groove is provided with a filter grid at the end corresponding to the fluid channel.

[0017] The beneficial effects of the present application are mainly reflected in that the erosion of the valve plate can be reduced, and the overall service life is improved. Specifically, in the use process, the mud and other fluids enter through the fluid channel on the first valve body. Since the fluid channel is inclined, the mud will not directly flush the surface of the valve plate, but will impact the surface of the valve plate at an angle, which can buffer and release the impact force, thereby avoiding deformation and damage of the valve plate under long-term erosion. The special included angle a range is preferably designed, and the included angle a range of 5-15°, especially 7°, can ensure the smoothness of the fluid flow and also consider the buffering property of the fluid flushing force. By spraying a hard alloy layer on the sealing surface of the valve plate, the anti-erosion property of the valve plate is further improved. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a structural schematic view of the present application when the valve plate is opened;

[0019] Figure 2 is a structural schematic view of the structure shown in Figure 1 when the valve plate is closed;

[0020] Figure 3 A preferred embodiment of the structure shown in Figure 2 A preferred embodiment of the structure shown in

[0021] Figure 4 A preferred embodiment of the structure shown in Figure 3 A preferred embodiment of the structure shown in

[0022] Figure 5 A preferred embodiment of the structure shown in A preferred embodiment of the structure shown in

[0023] Reference signs: 0, fluid passage; 1, first valve body; 2, second valve body; 3, side branch arm; 4, valve plate; 5, hinged lug; 6, hinged shaft; 7, reset torsion spring; 8, inner bushing; 9, sealing ring; 10, end groove; 11, adjusting block; 12, side groove; 13, connecting pipe; 14, moving plunger; 15, connecting rod; 16, pressure bag; 17, filter grid. DETAILED DESCRIPTION

[0024] As shown in Figure 1 , the present application is a long-acting anti-erosion float valve, which, like the existing flap float valve, comprises a hollow first valve body 1 and a second valve body 2, which are usually integrally formed and connected by a side branch arm 3. The number of side branch arms 3 is usually two, and the gap between the side branch arms 3 is formed.

[0025] The first valve body 1 is hingedly provided with a valve plate 4 on the side branch arm 3 near one end of the second valve body 2, and an elastic member is provided at the valve plate 4 to reset the valve plate 4 to close the fluid passage 0 in the first valve body 1.

[0026] As shown in Figure 2 , the side of the valve plate 4 facing the first valve body 1 is usually flat to ensure stable contact with the end of the first valve body 1 and form a good seal. The side facing the second valve body 2 is convex, similar to a boss, to better cope with reverse flow conditions such as well overflow and better disperse the stress to the entire valve plate 4.

[0027] From the hinged setting of the valve plate 4, there are many alternative hinge structures, for example: as shown in Figure 1 , a hinged lug 5 is provided on the side of the valve plate 4 near the hinge center (the upper side in Figure 1 , and a hinged shaft 6 is provided on the side branch arm 3 opposite the hinged lug 5, and the valve plate 4 and the hinged lug 5 are hingedly connected on the hinged shaft 6. Figure 2 and Figure 5 , the elastic member is usually a reset torsion spring 7, one leg of which is placed on the back of the valve plate 4, and the other leg is fixed to the end of the first valve body 1.

[0028] Figure 1And 2 As shown in the drawings, the fluid passage 0 on the first valve body 1 of the present application is different from the existing mode of extending along the axial direction of the first valve body 1, and is arranged obliquely and forms an included angle a with the axis of the first valve body 1, the included angle a is usually set to 5-15°, and 7° is optimal, which can ensure the smoothness of the fluid flow and also take into account the buffering of the fluid scouring force.

[0029] In use, the fluid such as mud enters through the fluid passage 0 on the first valve body 1, at this time the valve plate 4 is in an open state under the action of pressure, since the fluid passage 0 is arranged obliquely, in the opening process, the mud does not directly cause frontal scouring to the surface of the valve plate 4, but obliquely impacts the surface of the valve plate 4, which can buffer and release the impact force, thereby avoiding deformation and damage of the valve plate 4 under long-term erosion. After the valve plate 4 is opened, the valve plate 4 is located in the gap between the side arms 3, and it is preferably located on the side away from the fluid movement direction of the fluid passage 0 in the first valve body 1, thereby further avoiding the impact of the fluid on the valve plate 4, as shown in Figure 1 After the fluid passage 0 on the first valve body 1 of the present application is designed obliquely, it is usually deviated to the non-hinged side of the valve plate 4 (lower side in Figure 1 ), that is, the fluid passage 0 on the first valve body 1 is inclined along the fluid direction to the side of the valve plate 4 away from the hinged center. In this way, after the valve plate 4 is opened, the fluid will not directly impact the valve plate 4.

[0030] In order to further improve the sealing performance, a sealing step is arranged on the inner circumferential surface of the first valve body 1 near one end of the valve plate 4, and an inner bushing 8 and a sealing ring 9 are arranged at the sealing step. In addition, in order to strengthen the performance of the impact surface of the valve plate 4, a hard alloy layer is sprayed on the side of the valve plate 4 opposite to the fluid passage 0 on the first valve body 1. As shown in Figure 2 , that is, the left side of the valve plate 4 is sprayed with a hard alloy layer, and the surface of the valve plate 4 is strengthened by the hard alloy layer.

[0031] In long-term use, as the fluid such as mud is pumped in, the valve plate 4 is in the open state as shown in Figure 1 , at this time the reset torsion spring 7 is under long-term stress, and is easily affected by vibration caused by fluid flow, which can cause elastic fatigue, and further cause the reset effect of the reset torsion spring 7 to decrease. In order to solve the above problem, the better way of the present application is also:

[0032] As shown in Figure 3 and 4As shown in the figure, the first valve body 1 is provided with an end slot 10 on the end face opposite to the reset torsion spring 7, and an adjusting block 11 capable of sliding along the length direction of the end slot 10 is arranged in the end slot 10, and the leg of the reset torsion spring 7 is inserted into the adjusting block 11. That is, by changing the position of the adjusting block 11, one leg of the reset torsion spring 7 can be pushed to move towards the direction of the body of the reset torsion spring 7, so as to reduce the effective arm length of the leg (such as the distance from the contact point of the rightmost side of the adjusting block 11 to the body of the reset torsion spring 7), and under the condition that the pre-tightening force of the reset torsion spring 7 is unchanged, the total elasticity of the reset torsion spring 7 is reduced; and under the condition that the effective arm length of the other leg is unchanged, the elastic load at the leg is reduced, so as to reduce the fatigue risk. Figure 4

[0033] As shown in the figure, that is, when high-pressure fluid is injected into the fluid passage 0, as the pressure in the first valve body 1 rises, the adjusting block 11 is driven to move rightwards, the effective arm of the corresponding upper leg of the reset torsion spring 7 is shortened, and the elastic load of the other leg is reduced; as the fluid is no longer injected into the first valve body 1, the pressure in the first valve body 1 is reduced, the adjusting block 11 is driven to move leftwards, the effective arm of the corresponding upper leg of the reset torsion spring 7 is lengthened, and the overall output reset elastic force is ensured. Figure 4

[0034] In order to drive the adjusting block 11, the first valve body 1 of the present application is provided with a side slot 12 on the inner side wall of the fluid passage 0 close to the end slot 10, and the side slot 12 and the end slot 10 are communicated through a connecting pipe 13. A movement plunger 14 in sliding fit with the connecting pipe 13 is arranged in the connecting pipe 13, and one end of the movement plunger 14 is connected with the adjusting block 11 through a connecting rod 15.

[0035] In use, as the pressure in the first valve body 1 rises, the movement plunger 14 can be pushed to move rightwards, that is, the overall output reset elastic force of the valve plate 4 in the open state is reduced, so as to reduce the load; and as the fluid pressure in the first valve body 1 is reduced (stopping pumping) or well surge occurs, as the pressure on the second valve body 2 side rises, the movement plunger 14 can be pushed to move leftwards, that is, the overall output reset elastic force of the valve plate 4 in the closed state is increased, so as to meet the effective sealing requirement of the valve plate 4.

[0036] ​​On this basis, since the pumped fluid of the present application has many impurities and low cleanliness, the connecting pipe 13 is easily contaminated after entering the connecting pipe 13, causing the movement of the moving plunger 14 to be limited. In order to further ensure the stability of the movement of the moving plunger 14, a pressure bag 16 can also be provided in the side groove 12, and the pressure bag 16 is in communication with the connecting pipe 13. The pressure bag 16 is filled with pressure transmission medium, which is generally hydraulic oil; so as to transmit the pressure through the hydraulic oil, and ensure the stability of the action of the moving plunger 14. In order to form a certain protection for the pressure bag 16, avoid the impact of stones, impurities and the like on the pressure bag 16, the side groove 12 is provided with a filter grid 17 at one end corresponding to the fluid passage 0.

Claims

1. A long-lasting anti-erosion float valve, comprising a hollow first valve body (1) and a second valve body (2) having a fluid channel (0) inside, the first valve body (1) and the second valve body (2) being connected by a side support arm (3); a valve plate (4) is hinged on the side support arm (3) at one end of the first valve body (1) near the second valve body (2), and an elastic element is provided at the valve plate (4) for resetting the valve plate (4) to close the fluid channel (0) on the first valve body (1); Its features are: The fluid passage (0) on the first valve body (1) is inclined and forms an angle α with the axis of the first valve body (1); The elastic element is a reset torsion spring (7); An end groove (10) is provided on the end face opposite to the reset torsion spring (7) of the first valve body (1). An adjustment block (11) that can slide along the length direction of the end groove (10) is provided in the end groove (10). The support leg of the reset torsion spring (7) is inserted into the adjustment block (11). The first valve body (1) has a side groove (12) on the inner wall of the fluid channel (0) near the end groove (10). The side groove (12) and the end groove (10) are connected by a connecting pipe (13). A moving plunger (14) is provided in the connecting pipe (13) and forms a sliding fit with the connecting pipe (13). One end of the moving plunger (14) is connected to the adjusting block (11) through a connecting rod (15).

2. The long-life anti-erosion float valve according to claim 1, characterized in that: The included angle α is 5-15°.

3. The long-life anti-erosion float valve according to claim 2, characterized in that: The included angle α is 7°.

4. The long-life anti-erosion float valve according to claim 1, characterized in that: The fluid passage (0) on the first valve body (1) is inclined along the fluid direction toward the side of the valve plate (4) away from the hinge center.

5. The long-life anti-erosion float valve according to claim 1, characterized in that: The valve plate (4) opposite to the fluid channel (0) on the first valve body (1) is sprayed with a hard alloy layer.

6. The long-life anti-erosion float valve according to claim 1, characterized in that: The valve plate (4) is provided with a hinge ear (5) on the side near the hinge center. The side support arm (3) is provided with a hinge shaft (6) at the position opposite to the hinge ear (5). The valve plate (4) and the hinge ear (5) are sleeved on the hinge shaft (6) to form a hinge. One leg of the reset torsion spring (7) rests on the back of the valve plate (4), and the other leg is fixed to the end of the first valve body (1).

7. The long-life anti-erosion float valve according to claim 1, characterized in that: The first valve body (1) has a sealing step on the inner circumferential surface near the valve plate (4), and an inner bushing (8) and a sealing ring (9) are provided at the sealing step.

8. The long-life anti-erosion float valve according to claim 1, characterized in that: A pressure bladder (16) is provided in the side groove (12), and the pressure bladder (16) is connected to the connecting pipe (13).

9. The long-life anti-erosion float valve according to claim 8, characterized in that: A filter grid (17) is provided at one end of the side groove (12) corresponding to the fluid channel (0).

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