Novel check valve for well washing through hollow rod

Abstract

The novel check valve comprises a righting spring rod, the outer side of the righting spring rod is sleeved with a spring, the left side of the spring is inserted into an inner valve ball seat, and the inner valve ball seat is movably inserted into a valve seat; the sealing ring is movably inserted into the inner valve ball seat and is positioned on the outer side of the valve head of the inner valve ball seat; and an inserting section is arranged at the liquid outlet end of the inner valve seat. According to the equipment provided by the embodiment of the invention, the inner hexagonal groove is formed in the outer end part of the adjusting screw rod, and the adjusting screw rod is screwed through an external tool to adjust the position of the righting spring rod, so that the compression amount of the spring can be adjusted, the contraction force of the spring is adjusted, and the sealing opening pressure is adjusted; a sealing assembly in the valve seat is composed of an inner valve ball seat, a spring and a righting spring rod and is of a double-righting structure, so that the displacement of the inner valve ball seat is more stable, the sealing performance is effectively guaranteed, overflowing is changed into a long groove type liquid outlet from a traditional hole, and the overflowing area is increased.

Description

Technical Field

[0001] The present application relates to the technical field of downhole check valves, and in particular to a new type of hollow rod check valve for well washing. Background Art

[0002] A check valve is a device that allows fluid to flow only along the inlet, but the medium at the outlet cannot flow back. It is commonly known as a check valve. A check valve is also called a non-return valve. It is used in hydraulic systems to prevent oil from flowing in the opposite direction, or in pneumatic systems to prevent compressed air from flowing in the opposite direction. Check valves are available in two types: straight-through and right-angle. Straight-through check valves are installed on the pipeline with threaded connections. Right-angle check valves are available in three types: threaded, plate-type, and flanged.

[0003] Oil production is actively promoting CCUS pilot tests in order to achieve the dual goals of carbon sequestration and significantly increase oilfield recovery. The oil wells of the oilfield CCUS project use hollow rod well washing technology. The check valve used in the traditional hollow rod well washing has unsatisfactory use effect in the downhole oil and gas high pollution environment, and there are problems such as unadjustable sealing pressure, small flow area and easy clogging, and unreliable sealing method. Therefore, we proposed a new check valve for hollow rod well washing. Summary of the invention

[0004] The present application provides a new type of check valve for hollow rod well washing, in order to solve the problems that the check valve used in the conventional hollow rod well washing has poor performance in the downhole oil and gas highly polluted environment, has unadjustable sealing pressure, small flow area and easy clogging, and unreliable sealing method.

[0005] In order to solve the above technical problems or at least partially solve the above technical problems, the present application provides a new type of hollow rod check valve for well washing, including:

[0006] A righting spring rod, the outer side of which is sleeved with a spring, the left side of which is inserted into the inner valve ball seat, the inner valve ball seat is movably inserted into the inner side of the valve seat, and the right end of the righting spring rod is rotatably connected with an adjusting screw;

[0007] A sealing ring, which is movably inserted into the inner valve ball seat and is located outside the valve head of the inner valve ball seat;

[0008] An inner valve seat, wherein a plug-in section is provided at a liquid outlet end of the inner valve seat, and the plug-in section is plugged into the inner left side of the valve seat through a thread.

[0009] Optionally, the sealing ring is pressed and fitted with the opposite end of the plug-in section, and the left end of the sealing ring is fixedly connected with a first rubber sealing ring.

[0010] Optionally, a second rubber sealing ring is fixedly connected to the outer end of the plug-in section.

[0011] Optionally, a plurality of liquid outlets are formed in a ring array on the right side of the valve seat.

[0012] Optionally, the sealing end of the inner valve ball seat is hemispherical, and the inner valve ball seat is provided with a circular tube on the right side of the hemispherical sealing end.

[0013] Optionally, the outer wall of the circular tube is pressed and fitted with the inner wall of the valve seat.

[0014] Optionally, the right end of the straightening spring rod is fixedly connected to the right end of the inner cavity of the valve seat.

[0015] Optionally, the right end of the valve seat is fixedly connected to a connecting seat.

[0016] Optionally, two sections of cavities are provided inside the inner valve seat, and the inner diameters of the inner valve seat and the plug-in section decrease sequentially from left to right.

[0017] Optionally, the left side of the outer side of the adjusting screw is a round rod, and the right side of the outer side of the adjusting screw is a threaded rod. The outer side of the threaded rod is inserted into the middle of the threaded ring through threads, and the outer side of the threaded ring is fixedly connected to a circular groove opened in the middle of the connecting seat.

[0018] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0019] The device provided in the embodiment of the present application has a hexagonal groove on the outer end of the adjusting screw. The adjusting screw is turned by an external tool to adjust the position of the righting spring rod, thereby adjusting the compression of the spring, thereby adjusting the contraction force of the spring, thereby adjusting the seal opening pressure. The sealing assembly inside the valve seat is composed of an inner valve ball seat, a spring and a righting spring rod, and has a double righting structure, so that the displacement of the inner valve ball seat is more stable, effectively ensuring the sealing performance, and the flow is changed from a traditional hole to a long groove liquid outlet, and the flow area is increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0022] Figure 1 This is the overall structure diagram of a new type of hollow rod check valve for well washing;

[0023] Figure 2 A cross-sectional view of a new type of hollow rod check valve for well washing.

[0024] In the figure: 1. inner valve seat; 2. valve seat; 3. liquid outlet; 4. connecting seat; 5. plug-in section; 6. second rubber sealing ring; 7. first rubber sealing ring; 8. sealing ring; 9. inner valve ball seat; 10. righting spring rod; 11. spring. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0026] Various embodiments of the present application may exist in the form of a range. It should be understood that the description in the form of a range is only for convenience and simplicity and should not be understood as a hard limit to the scope of the present application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single values ​​within the range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which are applicable regardless of the range. In addition, whenever a numerical range is indicated in the present application, it is meant to include any quoted numbers (fractions or integers) within the indicated range. Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present application, etc., can be purchased from the market or can be prepared by existing methods.

[0027] In the present application, in the absence of any contrary description, the directional words used, such as "upper" and "lower", are specifically the directions of the drawings in the accompanying drawings. In addition, in the present application, the terms "include", "comprise", etc. refer to "including but not limited to". In the present application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. In the present application, "and / or" describes the association relationship of the associated objects, indicating that three relationships may exist, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. Wherein A, B can be singular or plural. In the present application, "at least one" refers to one or more, and "plural" refers to two or more. "At least one", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of singular items or plural items. For example, "at least one of a, b, or c" or "at least one of a, b and c" can both mean: a, b, c, ab, i.e. a and b, ac, bc or abc, where a, b, c can be single or plural, respectively.

[0028] like Figure 1-Figure 2 As shown, the embodiment of the present application provides a new type of hollow rod check valve for well washing, including:

[0029] A righting spring rod 10, the outer side of which is sleeved with a spring 11, the left side of which is inserted into the inner valve ball seat 9, the inner valve ball seat 9 is movably inserted into the inner side of the valve seat 2, and the right end of the righting spring rod 10 is rotatably connected with an adjusting screw 12;

[0030] A sealing ring 8, wherein the sealing ring 8 is movably inserted into the inner valve ball seat 9 and is located outside the valve head of the inner valve ball seat 9;

[0031] The inner valve seat 1 has a plug-in section 5 at the liquid outlet end thereof, and the plug-in section 5 is plugged into the left side of the inner portion of the valve seat 2 by means of threads.

[0032] Specifically, the length of the righting spring rod 10 is such that when the spring 11 is in a free state, the left side of the righting spring rod 10 is inserted into the right side of the inner valve ball seat 9, so that when the spring 11 is compressed, the deformation state of the butterfly spring 11 can be stabilized, and the displacement of the inner valve ball seat 9 can be more stable;

[0033] The outer surface of the inner valve ball seat 9 is smooth, and the outer wall of the inner valve ball seat 9 and the inner wall of the valve seat 2 are pressed, fitted and slid to limit the displacement of the inner valve ball seat 9;

[0034] The inner side of the sealing ring 8 is provided with a notch that matches the outer side of the inner valve ball seat 9, thereby increasing the area of ​​the sealing ring 8 in compression contact with the end face of the inner valve ball seat 9, thereby increasing the sealing effect of the sealing ring 8, and a sealing gasket is connected to the side wall of the notch that matches the outer side of the inner valve ball seat 9 provided on the inner side of the sealing ring 8, thereby increasing the sealing degree of the sealing ring 8;

[0035] By turning the adjusting screw 12 to adjust the position of the straightening spring rod 10, the compression amount of the spring 11 can be adjusted, thereby adjusting the contraction force of the spring 11, thereby adjusting the seal opening pressure, thereby adjusting the seal opening pressure.

[0036] The overall structure is simple and the practical effect is stable. The inner valve ball seat 9 is a tubular structure, which increases the contact area between the inner valve ball seat 9 and the inner side of the outer shell, thereby increasing the stability of the operation of the inner valve ball seat 9.

[0037] like Figure 2 As shown, the sealing ring 8 is pressed and fitted with the opposite end of the plug-in section 5 , and the left end of the sealing ring 8 is fixedly connected with the first rubber sealing ring 7 .

[0038] Specifically, the first rubber sealing ring 7 can increase the sealing degree of the plug-in section 5 and the sealing ring 8, and the first rubber sealing ring 7 has high elasticity and high strength.

[0039] like Figure 2 As shown: the outer end of the plug-in section 5 is fixedly connected with a second rubber sealing ring 6.

[0040] Specifically, the second rubber sealing ring 6 can seal the gap at the connection between the valve seat 2 and the plug-in section 5 , and the second rubber sealing ring 6 has high elasticity and high strength.

[0041] like Figure 1 As shown: the right side of the valve seat 2 is provided with a plurality of liquid outlets 3 in a circular array.

[0042] Specifically, the liquid outlet 3 is the outlet of the liquid, and the liquid outlet 3 is a long rectangular opening with arc-shaped ends, so as to increase the amount of liquid outlet from the liquid outlet 3 .

[0043] like Figure 2 As shown: the sealing end of the inner valve ball seat 9 is hemispherical, and the inner valve ball seat 9 is provided with a round tube on the right side of the hemispherical sealing end.

[0044] The outer wall of the circular tube is pressed and fitted with the inner wall of the valve seat 2 .

[0045] Specifically, the inner valve ball seat 9 is limited by the inner side wall of the valve seat 2, so that its movement is more stable.

[0046] like Figure 2As shown: the right end of the straightening spring rod 10 is fixedly connected to the right end of the inner cavity of the valve seat 2.

[0047] Specifically, the straightening spring rod 10 can make the compression and extension of the spring 11 more stable.

[0048] like Figure 1 As shown: the right end of the valve seat 2 is fixedly connected with a connecting seat 4.

[0049] Specifically, the connection seat 4 can position and connect the entire structure on a fixed device; a stepped circular hole is opened in the middle of the connection seat 4, and the left side of the stepped circular hole is sealed and plugged with the left round rod of the adjusting screw 12.

[0050] Specifically, the connection seat 4 is cylindrical, and a hole for bolt insertion and fixing may be provided on the surface, or a thread may be provided to be inserted into and matched with a screw hole provided in an external device for positioning.

[0051] like Figure 2 As shown, the inner valve seat 1 is provided with two sections of cavities, and the inner diameters of the inner valve seat 1 and the plug-in section 5 decrease from left to right.

[0052] Specifically, the inner cavity structure of the inner valve seat 1 and the plug-in section 5 has the effect of accelerating the flow rate of the liquid.

[0053] Specifically, the inner valve seat 1 is an inlet interface structure, and a threaded structure, a snap-fit ​​structure or a flange structure may be provided inside the inner valve seat 1 .

[0054] like Figure 2 As shown: the left side of the outer side of the adjusting screw 12 is a round rod, and the right side of the outer side of the adjusting screw 12 is a threaded rod. The outer side of the threaded rod is inserted into the middle of the threaded ring 13 through threads, and the outer side of the threaded ring 13 is fixedly connected to the circular groove opened in the middle of the connecting seat 4.

[0055] Specifically: a hexagonal groove is formed at the outer end of the adjusting screw 12. The adjusting screw 12 is screwed by an external tool to adjust the position of the straightening spring rod 10, thereby adjusting the compression amount of the spring 11, thereby adjusting the contraction force of the spring 11, thereby adjusting the seal opening pressure, thereby adjusting the seal opening pressure.

[0056] When the equipment is in use, the inner valve seat 1 is the liquid inlet, and the outer end of the adjusting screw 12 is provided with an inner hexagonal groove. The adjusting screw 12 is twisted by an external tool to adjust the position of the righting spring rod 10, so that the compression amount of the spring 11 can be adjusted, thereby adjusting the contraction force of the spring 11 to adjust the seal opening pressure. When water enters, when the pressure overcomes the force of the spring 11, the inner valve ball seat 9 is displaced to the right, so that the liquid outlet 3 and the internal liquid cavity of the valve seat 2 are connected to each other, so that the liquid outlet 3 can discharge liquid. The sealing component inside the valve seat 2 is composed of the inner valve ball seat 9, the spring 11 and the righting spring rod 10, and has a double righting structure, which makes the displacement of the inner valve ball seat 9 more stable, effectively ensuring the sealing performance, and the flow is changed from the traditional hole to the long groove type liquid outlet 3, and the flow area is increased.

[0057] The protection points of this application document are: (1) the floating design of the righting spring rod 10, thereby adjusting the contraction force of the spring 11, thereby adjusting the seal opening pressure; (2) the valve seat sealing component has a double righting structure, which has reliable sealing performance in a highly polluted working environment. At the same time, the elongated inner valve ball seat 9 (that is, the inner valve ball seat 9 is a tubular structure) increases the contact area between the inner valve ball seat 9 and the inner side of the outer shell, thereby increasing the stability of the operation of the inner valve ball seat 9.

[0058] Example:

[0059] In the pilot test project, the Majian 3 well, with a well depth of 3700m, an estimated wax deposition depth of 700m, and a hollow rod length of 1000m, was tested using the check valve. 3 , the hot washing pressure is controlled within 0.2MPa-0.2MPa, the displacement is controlled at 3 to 3.5m3 per hour, the hot washing car outlet temperature is controlled between 60-65℃, the return water outlet is clear, and the well washing effect is good;

[0060] The structure of this equipment is suitable for CCUS oil production wells in oil and gas fields. It is a hollow rod well washing check valve for oil production wells. On the basis of traditional check valves, it solves the problems of corrosion protection and flow area, making it more suitable for CCUS pilot tests.

[0061] The Chinese patent number is: CN201810265U discloses a hollow rod well washing check valve, the end of the upper joint is connected with a hollow middle joint a, a hollow middle joint b, a hollow lower joint and a variable thread plug in sequence, the middle joint b is provided with a valve core a, a chamber c and a chamber d which are internally connected in sequence, and a reverse ball a is provided between chamber c and chamber d; the lower joint is provided with a valve core b, a chamber f and a chamber g which are internally connected in sequence, and a reverse ball b is provided between chamber f and chamber g; the upper joint is provided with a chamber a, and the end of the chamber a is provided with an axial through hole, which is respectively connected with the interior of chambers d and g. The hollow rod well-washing check valve of the present invention has a simple structure and is easy to use. The cleaning agent can enter chamber d and chamber g respectively, and then flow into the oil pipe through radial through hole a and radial through hole b. It has the advantages of good one-way flow effect and high well-washing displacement, and can be used for oil well wax cleaning and sewage discharge. That is, the hollow rod well-washing check valve of the present invention, the well-washing fluid enters chamber a, and enters chamber d and chamber g respectively through the axial through hole; the well-washing fluid entering chamber d pushes the ball a to enter chamber c, and then enters chamber b through valve core a and is discharged into the oil pipe through radial through hole a; the well-washing fluid entering chamber g pushes the ball b to enter chamber f, and then enters chamber e through valve core b and is discharged into the oil pipe through radial through hole b. In this way, the cleaning fluids with the same temperature enter the middle and lower parts of the oil pipe respectively, and the oil pipe drives the well-washing fluid upward to flow along the oil pipe, so as to dissolve the viscous matter and wax on the inner wall of the oil pipe, and finally carry it to the ground to achieve the purpose of cleaning. It has a simple structure, is easy to use, has the advantages of good one-way flow effect and high well washing capacity, and can be used for oil well wax removal and sewage discharge;

[0062] However, the overall structure of the above-mentioned invention patent is complex, and there are many chambers arranged inside, which can easily cause blockage of the internal chambers, thereby affecting the use of the device;

[0063] Compared with the present application document: the present application document has a simple structure, fewer internal chambers, and the position of the straightening spring rod 10 can be adjusted by turning the adjusting screw 12 with an external tool, thereby adjusting the compression amount of the spring 11, thereby adjusting the contraction force of the spring 11, thereby adjusting the seal opening pressure, thereby adjusting the seal opening pressure, and being able to meet the opening and passing of different media. The extended inner valve ball seat 9 (that is, the inner valve ball seat 9 is a tubular structure) increases the contact area between the inner valve ball seat 9 and the inner side of the outer shell, thereby increasing the stability of the operation of the inner valve ball seat 9.

[0064] The above is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. It will be apparent to those skilled in the art that various modifications to these embodiments are possible, and the general principles defined in the present application can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown in the present application, but will conform to the widest scope consistent with the principles and novel features applied for by the present application.

Claims

1. A new type of hollow rod check valve for well washing, characterized in that: include: A righting spring rod (10), the outer side of the righting spring rod (10) is sleeved with a spring (11), the left side of the spring (11) is inserted into the inner valve ball seat (9), the inner valve ball seat (9) is movably inserted into the inner side of the valve seat (2), and the right end of the righting spring rod (10) is rotatably connected to an adjusting screw (12); A sealing ring (8), the sealing ring (8) is movably inserted into the interior of the inner valve ball seat (9) and is located outside the valve head of the inner valve ball seat (9); An inner valve seat (1), wherein a plug-in section (5) is provided at a liquid outlet end of the inner valve seat (1), and the plug-in section (5) is plugged into the inner left side of the valve seat (2) via a thread.

2. The new type of hollow rod well washing check valve according to claim 1 is characterized by: The sealing ring (8) is pressed and fitted with the opposite end of the plug-in section (5), and the left end of the sealing ring (8) is fixedly connected to the first rubber sealing ring (7).

3. The new type of hollow rod well washing check valve according to claim 1 is characterized by: The outer end of the plug-in section (5) is fixedly connected to a second rubber sealing ring (6).

4. The new type of hollow rod well washing check valve according to claim 1 is characterized by: The right side of the valve seat (2) is provided with a plurality of liquid outlets (3) in a ring array.

5. The new type of hollow rod well washing check valve according to claim 1 is characterized by: The sealing end of the inner valve ball seat (9) is hemispherical, and a circular tube is provided on the right side of the hemispherical sealing end of the inner valve ball seat (9).

6. The new type of hollow rod well washing check valve according to claim 5 is characterized by: The outer wall of the circular tube is pressed and fitted with the inner wall of the valve seat (2).

7. The new type of hollow rod well washing check valve according to claim 1 is characterized by: The right end of the straightening spring rod (10) is fixedly connected to the right end of the inner cavity of the valve seat (2).

8. The new type of hollow rod well washing check valve according to claim 1 is characterized by: The right end of the valve seat (2) is fixedly connected to a connecting seat (4).

9. The new type of hollow rod well washing check valve according to claim 1 is characterized by: The inner valve seat (1) is provided with two sections of cavities, and the inner diameters of the inner valve seat (1) and the plug-in section (5) decrease from left to right.

10. The new type of hollow rod well washing check valve according to claim 1 is characterized by: The left side of the outer side of the adjusting screw (12) is a round rod, and the right side of the outer side of the adjusting screw (12) is a threaded rod. The outer side of the threaded rod is inserted into the middle of the threaded ring (13) through threads, and the outer side of the threaded ring (13) is fixedly connected to a circular groove opened in the middle of the connecting seat (4).

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