High-temperature-resistant and high pressure resistant composite one way valve

Abstract

A high-temperature-resistant and high-pressure-resistant composite one-way valve, comprising an upper valve body (1) and a lower valve body (2) which are connected into a whole by means of a temperature-resistant structural adhesive. A central hole (21) is axially formed in the center of the lower valve body (2); a valve core (3) is provided in the central hole (21); the valve core (3) is integrally cast with a guide rod (7) and a special concrete layer (6) by means of a mold; a rubber layer (5) is provided on the outer surface of the special concrete layer (6); the special concrete layer (6) and the rubber layer (5) are molded into a whole by using a vulcanization molding process; the rubber layer (5) is tightly attached to the upper valve body (1) by means of a conical surface; a spring (4) is sleeved on the guide rod (7); and the lower end of the spring (4) and the lower end of the guide rod (7) are both located in the central hole (21). The valve can withstand a high temperature of 205°C and a high pressure of 10,000 psi.

Description

The present disclosure relates to the technical field of oil drilling, production and well cementing apparatus, and particularly relates to a high-temperature and high-pressure resistant composite check valve. Background The floating apparatus is a key component for running casing and performing well cementing operations. The floating apparatus generally includes one or more check valves and forms part of the lower section of the casing, so as to prevent the cement slurry entering the annular space of the well wall from flowing back. The floating apparatus must withstand pressure and higher pressure from below the check valve and can be used normally in the temperature environment to which it is exposed. In addition, the check valve, as a component of the floating apparatus, is crucial for preventing backflow, and is fundamental to the success of the well cementing operations. When a currently available composite check valve is used in a high temperature (205°C) and high pressure (10000 psi) environment, the valve core material of the check valve is prone to softening, which may cause damage to the valve core, and lead to failure of the sealing function of the check valve and backflow of cement slurry during the well cementing process, thus causing failure of the well cementing, and resulting in significant economic losses. Summary The purpose of the present disclosure is to provide a high-temperature and high-pressure resistant composite check valve, which has the characteristic of high-temperature and high-pressure resistance. The technical solution adopted in the present disclosure is: a high-temperature and high-pressure resistant composite check valve, including an upper valve body and a lower valve body that are integrally connected by a temperature-resistant structural adhesive; wherein the lower valve body is provided with a central hole in a direction of a central axis; the valve core is provided in the central hole; the valve core is integrally cast from the guide rod and the special concrete layer using a mold; the rubber layer is provided on an outer surface of the special concrete layer; the special concrete layer and the rubber layer are integrally molded using a vulcanization molding process; the rubber layer is tightly bonded to the upper valve body through a tapered surface; the spring is sleeved on the guide rod; and both a lower end of the spring and a lower end of the guide rod are located in the central hole. In some embodiments, one end of the guide rod is provided with an inverted buckling structure, and the guide rod is fixedly connected to the special concrete layer through the inverted buckling structure. In some embodiments, a design thickness of the rubber layer is from 1 mm to 3 mm. In some embodiments, a design thickness of the rubber layer is 1.5 mm. In some embodiments, the upper valve body is made of a high-strength and temperature-resistant PPS composite material through injection molding, and a wall thickness of the upper housing of the upper valve body is from 1 mm to 5 mm. In some embodiments, a wall thickness of the upper housing of the upper valve body is 2 mm. In some embodiments, an outer surface of the upper valve body is uniformly provided with several anti-rotation protrusions. In some embodiments, a carbon molecular structure framework is provided inside the special concrete layer, and the carbon molecular structure framework is integrally cast with the special concrete layer in a single molding process. In some embodiments, a compressive strength of the carbon molecular structure framework and the special concrete layer after cast-molding is greater than or equal to 10000 psi. In some embodiments, a temperature that the carbon molecular structure framework and the special concrete layer can withstand after cast-molding is greater than or equal to 205°C. In some embodiments, the carbon molecular structure framework is formed from any one of materials selected from carbon fiber, titanium alloy, high-strength resin and aluminum alloy by printing using 3D printing technology. In some embodiments, the rubber layer is an oil-resistant, temperature-resistant, and wearresistant fluorine rubber layer. In some embodiments, the upper valve body includes an upper housing; wherein the upper housing is provided with a first hole body and a second hole body that are connected to each other; the first hole body is located at an end of the second hole body away from the lower valve body; and a diameter of the second hole body gradually decreases in a direction towards the first hole body for bonding with the rubber layer. In some embodiments, an outer peripheral surface of the special concrete layer includes a tapered mating surface corresponding to a hole wall surface of the second hole body, and at least a portion of the rubber layer covers the tapered mating surface. In some embodiments, the upper valve body includes an upper housing and a first coupling portion provided at a lower end of the upper housing; the lower valve body includes a lower housing and a second coupling portion provided at an upper end of the lower housing; and the first coupling portion and the second coupling portion are inserted-connect fit. In some embodiments, the first coupling portion is an annular insertion groove; the second coupling portion is an annular insertion protrusion; the temperature-resistant structural adhesive is coated in the annular insertion groove; and a guiding bevel is provided on a side of the annular insertion protrusion close to the upper valve body. In some embodiments, the lower valve body includes a lower housing and a central protrusion provided in the lower housing and located at a bottom of the lower housing, and the central hole is provided on the central protrusion. In some embodiments, the central hole includes a first hole section and a second hole section that are connected to each other; the first hole section is located at an end of the second hole section away from the upper valve body; a diameter of the first hole section is smaller than a diameter of the second hole section; a lower end of the guide rod passes through the second hole section and is then inserted into the first hole section; and the lower end of the spring is located in the second hole section and is in contact with a bottom surface of the second hole section. In some embodiments, the guiding rod includes a main rod body and a support seat provided at an upper end of the main rod body; the support seat is used for supporting the special concrete layer; and the spring is sleeved on the main rod body, and an upper end of the spring is in contact with the support seat. In some embodiments, the main rod body includes a first rod section and a second rod section that are sequentially connected in a direction away from the support seat; and an outer diameter of the first rod section is greater than an outer diameter of the second rod section. The beneficial effects of the present disclosure are as follows: with regard to the problem in the art known to inventors that a composite check valve is not resistant to high-temperature and high-pressure, in the high-temperature and high-pressure resistant composite check valve of the present disclosure, a technology that combines special concrete with a composite material is used to manufacture a check valve core, and a special rubber vulcanization process is applied to vulcanize a wear-resistant, temperature-resistant, and oil-resistant fluorine rubber surface layer on the surface of the special concrete; the upper valve body is formed from a high-strength, temperature-resistant composite material; the outer surface of the upper valve body is uniformly distributed with anti-rotation protrusions around its circumference; by utilizing a spring reset principle, the valve core is tightly fitted to the inner tapered surface of the upper valve body, such that the composite check valve can operate normally in an exposed environment with a high-temperature of 205°C and a high-pressure of 10,000 psi, effectively preventing the backflow of cement slurry entering the annular gap of the well wall. Brief Description of the Drawings Fig. 1 is a schematic diagram of the structure of a high-temperature and high-pressure resistant composite check valve according to the present disclosure; Fig. 2 is a schematic diagram of the structure of a valve core of a high-temperature and high-pressure resistant composite check valve according to the present disclosure; Fig. 3 is a schematic diagram of the structure of a high-temperature and high-pressure resistant composite check valve with a carbon molecule structure framework according to the present disclosure; Fig. 4 is a schematic diagram of the structure of a valve core of a high-temperature and high-pressure resistant composite check valve with a carbon molecule structure framework according to the present disclosure; Fig. 5 is a schematic diagram of the structure of a carbon molecule structure framework of a high-temperature and high-pressure resistant composite check valve with a carbon molecule structure framework according to the present disclosure; Fig. 6 is a schematic diagram of the overall structure of a high-temperature and high-pressure resistant composite check valve according to the present disclosure; Fig. 7 is a graph of the high-temperature and high-pressure test curves for composite valves currently available on the market; Fig. 8 is a graph of the high-temperature and high-pressure test curves for a composite check valve according to embodiment 2 of the present disclosure; Fig. 9 is a graph of the high-temperature and high-pressure test curves for a composite check valve with a carbon molecular structure framework according to embodiment 3 of the present disclosure. In the figures, 1. upper valve body; 10. upper housing; 11. first hole body; 12. second hole body; 13. first coupling portion; 14. anti-rotation protrusion; 2. lower valve body; 21. central hole; 211. first hole section; 212. second hole section; 22. central protrusion; 23. second coupling portion; 3. valve core;4. spring; 5. rubber layer; 6. special concrete layer; 7. guide rod; 71. main rod body; 711. first rod section; 712. second rod section;72. support seat; 8. carbon molecule structure framework. Detailed Description of the Embodiments The present disclosure will be described below in detail with reference to the accompanying drawings and specific embodiments. Embodiment 1 The structure of a high-temperature and high-pressure resistant composite check valve of the present disclosure is shown in Figs. 1 and 2, includes an upper valve body 1, a lower valve body 2, a valve core 3 and a spring 4; and as shown in Fig. 2, the valve core 3 includes a rubber layer 5, a special concrete layer 6, and a guide rod 7. The valve core 3 is integrally cast from the guide rod 7 and the special concrete layer 6 using a mold; one end of the guide rod 7 is provided with an inverted buckling structure to ensure a reliable connection with the special concrete layer 6; the special concrete layer 6 is integrally molded with the rubber layer 5 using a special vulcanization molding process; and a design thickness of the rubber layer 5 is from 1 mm to 3 mm. The upper valve body 1 is made of a high-strength and temperature-resistant PPS composite material through injection molding; a wall thickness of the housing of the upper valve body 1 is from 1 mm to 5 mm; an outer surface of the upper valve body 1 is uniformly provided with several anti-rotation projections 14; and the structure is shown in Fig. 6. The lower valve body 2 is provided with a central hole in a direction of a central axis ; the spring 4 is sleeved on the guide rod 7 of the valve core 3; and a lower end of the spring 4 and a lower end of the guide rod 7 are located together in the central hole of the lower valve body 2. The upper valve body 1 is tightly fitted with the rubber layer 5 of the valve core 3 though a tapered surface for sealing, and is integrally connected to the lower valve body 2 though a temperature-resistant structural adhesive. As shown in Figs. 4 and 5, a carbon molecular structure framework 8 is provided inside the special concrete layer 6; the carbon molecular structure framework 8 is integrally cast with the special concrete layer 6 in a single molding process; and the compressive strength thereof after castmolding can reach over 10000 psi. In the present disclosure, a temperature that the carbon molecular structure framework 8 and the special concrete layer 6 can withstand after cast-molding is greater than or equal to 205°C. With regard to the problem in the art known to inventors that a composite check valve is not resistant to high-temperature and high-pressure, in the high-temperature and high-pressure resistant composite check valve of the present disclosure, a technology that combines special concrete with a composite material is used to manufacture a check valve core, and a special rubber vulcanization process is applied to vulcanize a wear-resistant, temperature-resistant, and oil-resistant fluorine rubber surface layer on the surface of the special concrete; by utilizing a spring reset principle, the valve core 3 is tightly fitted to the inner tapered surface of the upper valve body, such that the composite check valve can operate normally in an exposed environment with a high-temperature of 205°C and a high-pressure of 10,000 psi, effectively preventing the backflow of cement slurry entering the annular gap of the well wall. Embodiment 2 The structure of a high-temperature and high-pressure resistant composite check valve of the present disclosure is as shown in Fig. 1, including an upper valve body 1, a lower valve body 2, a valve core 3 and a spring 4; and as shown in Fig. 2, the valve core 3 includes a rubber layer 5, a special concrete layer 6, and a guide rod 7. The valve core 3 is integrally cast from a guide rod 7 and a special concrete layer 6 using a mold; one end of the guide rod 7 is provided with an inverted buckling structure to ensure a reliable connection with the special concrete layer 6; the special concrete layer 6 is integrally molded with the rubber layer 5 using a special vulcanization molding process; the rubber layer 5 is an oil-resistant, temperature-resistant, and wear-resistant fluorine rubber layer; and a design thickness of the rubber layer is 1.5 mm. The upper valve body 1 is made of a high-strength and temperature-resistant PPS composite material through injection molding; the wall thickness of the housing of the upper valve body is 2 mm; and an outer surface of the upper valve body is uniformly provided with 24 anti-rotation projections 14. The lower valve body 2 is provided with a central hole in a direction of a central axis; the spring 4 is sleeved on the guide rod 7 of the valve core 3; and a lower end of the spring 4 and a lower end of the guide rod 7 are located together in the central hole of the lower valve body 2. The upper valve body 1 is tightly fitted with the rubber layer of the valve core 3 through a tapered surface, and is integrally connected to the lower valve body 2 through a temperature-resistant structural adhesive. Embodiment 3 As shown in Fig. 3, on the basis of embodiment 2, a carbon molecular structure framework 8 is added inside the valve core 3. The material of the carbon molecular structure framework 8 includes carbon fiber, titanium alloy, high-strength resin, aluminum alloy, etc., and the carbon molecular structure framework is formed by printing using 3D printing technology. The carbon molecular structure framework 8, the guide rod 7 and the special concrete layer 6 are finally integrally cast using a mold. The high-temperature and high-pressure resistant composite check valves in embodiments 2 and 3 of the present disclosure are compared with the composite valves currently popular in the market through API 10F testing, and specific comparison data is as shown in table 1 below: Table 1 API 10F Test Comparison Serial No. Valve Type Test Temperature (°C) Test Pressure (psi) 1 Composite valves the current market in 205 4800 2 The valve embodiment 2 in 205 10000 3 The valve embodiment 3 in 205 12000 The test curves of composite valves in the current market are shown in Fig. 7; the test curves of the high-temperature and high-pressure resistant composite check valve in embodiment 2 of the present disclosure are shown in Fig. 8; and the test curves of the high-temperature and high-pressure resistant composite check valve in embodiment 3 of the present disclosure are shown in Fig. 9. In conjunction with the test data in Figs. 7-9 and table 1, it can be found that the high-temperature and high-pressure resistant composite check valve of the present disclosure has a pressure resistance capability that is over twice that of the composite valves currently available in the market at a high temperature of 205°C. Embodiment 4 On the basis of any one of embodiments 1 to 3, the specific structure of the high-temperature and high-pressure resistant composite check valve of the present disclosure is as follows: as shown in Figs. 1 and 3, the upper valve body 1 includes an upper housing 10, wherein the upper housing 10 is provided with a first hole body 11 and a second hole body 12 that are connected to each other, the first hole body 11 is located at an end of the second hole body 12 away from the lower valve body 2, and a diameter of the second hole body 12 gradually decreases in a direction towards the first hole body 11 for bonding with the rubber layer 5. In some embodiments, an outer peripheral surface of the special concrete layer 6 includes a tapered mating surface corresponding to wall surface of hole of the second hole body 12, and at least a portion of the rubber layer 5 covers the tapered mating surface. As shown in Figs. 1 and 3, the upper valve body 1 includes an upper housing 10 and a first coupling portion 13 provided at a lower end of the upper housing 10; the lower valve body 2 includes a lower housing 20 and a second coupling portion 23 provided at an upper end of the lower housing 20; and the first coupling portion 13 and the second coupling portion 23 are inserted-connect fit. In some embodiments, the first coupling portion 13 is an annular insertion groove; the second coupling portion 23 is an annular insertion protrusion; the temperature-resistant structural adhesive is coated in the annular insertion groove; and a guiding bevel is provided on a side of the annular insertion protrusion close to the upper valve body 1. As shown in Figs. 1 and 3, the lower valve body 2 includes a lower housing 20 and a central protrusion 22 provided in the lower housing 20 and located at a bottom of the lower housing 20, and the central hole 21 is provided on the central protrusion 22. As shown in Figs. 1 and 3, the central hole 21 includes a first hole section 211 and a second hole section 212 that are connected to each other; the first hole section 211 is located at an end of the second hole section 212 away from the upper valve body 1; and a diameter of the first hole section 211 is smaller than a diameter of the second hole section 212; a lower end of the guide rod 7 passes through the second hole section 212 and is then inserted into the first hole section 211; and the lower end of the spring 4 is located in the second hole section 212 and is in contact with a bottom surface of the second hole section 212. As shown in Fig. 2, the guiding rod 7 includes a main rod body 71 and a support seat 72 provided at an upper end of the main rod body 71; the support seat 72 is used for supporting the special concrete layer 6; and the spring 4 is sleeved on the main rod body 71, and an upper end of the spring 4 is in contact with the support seat 72, wherein the main rod body 71 and the support seats 72 are integrally formed or detachably connected. As shown in Fig. 2, the main rod body 71 includes a first rod section 711 and a second rod section 712 that are sequentially connected in a direction away from the support seat 72; and an outer diameter of the first rod section 711 is greater than an outer diameter of the second rod section 712.

Claims

1. A high-temperature and high-pressure resistant composite check valve, comprising an upper valve body (1) and a lower valve body (2) that are integrally connected by a temperature-resistant structural adhesive; wherein the lower valve body (2) is provided with a central hole (21) in a direction of a central axis sthe valve core (3) is provided in the central hole; the valve core (3) is integrally cast from the guide rod (7) and the special concrete layer (6) using a mold; the rubber layer (5) is provided on an outer surface of the special concrete layer (6); the special concrete layer (6) and the rubber layer (5) are integrally molded using a vulcanization molding process; the rubber layer (5) is tightly bonded to the upper valve body (1) through a tapered surface; the spring (4) is sleeved on the guide rod (7); and both a lower end of the spring (4) and a lower end of the guide rod (7) are located in the central hole.

2. The high-temperature and high-pressure resistant composite check valve according to claim 1, wherein one end of the guide rod (7) is provided with an inverted buckling structure, and the guide rod (7) is fixedly connected to the special concrete layer (6) through the inverted buckling structure.

3. The high-temperature and high-pressure resistant composite check valve according to claim 1, wherein a design thickness of the rubber layer (5) is from 1 mm to 3 mm.

4. The high-temperature and high-pressure resistant composite check valve according to claim 1, wherein a design thickness of the rubber layer (5) is 1.5 mm.

5. The high-temperature and high-pressure resistant composite check valve according to claim 1, wherein the upper valve body (1) is made of a high-strength and temperature-resistant PPS composite material through injection molding, and a wall thickness of the upper housing (10) of the upper valve body (1) is from 1 mm to 5 mm.

6. The high-temperature and high-pressure resistant composite check valve according to claim 1, wherein a wall thickness of the upper housing (10) of the upper valve body (1) is 2 mm.

7. The high-temperature and high-pressure resistant composite check valve according to claim 1, wherein an outer surface of the upper valve body (1) is uniformly provided with several anti-rotation protrusions (14).

8. The high-temperature and high-pressure resistant composite check valve according to claim 1, wherein a carbon molecular structure framework (8) is provided inside the special concrete layer (6), and the carbon molecular structure framework (8) is integrally cast with the special concrete layer(6) in a single molding process.

9. The high-temperature and high-pressure resistant composite check valve according to claim 8, wherein a compressive strength of the carbon molecular structure framework (8) and the special concrete layer (6) after cast-molding is greater than or equal to 10000 psi.

10. The high-temperature and high-pressure resistant composite check valve according to claim 10, wherein a temperature that the carbon molecular structure framework (8) and the special concrete layer (6) can withstand after cast-molding is greater than or equal to 205°C.

11. The high-temperature and high-pressure resistant composite check valve according to claim 8, wherein the carbon molecular structure framework (8) is formed from any one of materials selected from carbon fiber, titanium alloy, high-strength resin and aluminum alloy by printing using 3D printing technology.

12. The high-temperature and high-pressure resistant composite check valve according to claim 1, wherein the rubber layer (5) is an oil-resistant, temperature-resistant, and wear-resistant fluorine rubber layer.

13. The high-temperature and high-pressure resistant composite check valve according to claim 1, wherein the upper valve body (1) comprises an upper housing (10); wherein the upper housing (10) is provided with a first hole body (11) and a second hole body (12) that are connected to each other; the first hole body (11) is located at an end of the second hole body (12) away from the lower valve body (2); and a diameter of the second hole body (12) gradually decreases in a direction towards the first hole body (11) for bonding with the rubber layer (5).

14. The high-temperature and high-pressure resistant composite check valve according to claim 13, wherein an outer peripheral surface of the special concrete layer (6) comprises a tapered mating surface corresponding to a hole wall surface of the second hole body (12), and at least a portion of the rubber layer (5) covers the tapered mating surface.

15. The high-temperature and high-pressure resistant composite check valve according to claim 1, wherein the upper valve body (1) comprises an upper housing (10) and a first coupling portion (13) provided at a lower end of the upper housing (10); the lower valve body (2) comprises a lower housing (20) and a second coupling portion (23) provided at an upper end of the lower housing (20); and the first coupling portion (13) and the second coupling portion (23) are inserted-connect fit.

16. The high-temperature and high-pressure resistant composite checkvalve according to claim 15,wherein the first coupling portion (13) is an annular insertion groove; the second coupling portion (23) is an annular insertion protrusion; the temperature-resistant structural adhesive is coated in the annular insertion groove; and a guiding bevel is provided on a side of the annular insertion protrusion close to the upper valve body (1).

17. The high-temperature and high-pressure resistant composite check valve according to claim 1, wherein the lower valve body (2) comprises a lower housing (20) and a central protrusion (22) provided in the lower housing (20) and located at a bottom of the lower housing (20), and the central hole (21) is provided on the central protrusion (22).

18. The high-temperature and high-pressure resistant composite check valve according to claim 1, wherein the central hole (21) comprises a first hole section (211) and a second hole section (212) that are connected to each other; the first hole section (211) is located at an end of the second hole section (212) away from the upper valve body (1); a diameter of the first hole section (211) is smaller than a diameter of the second hole section (212); a lower end of the guide rod (7) passes through the second hole section (212) and is then inserted into the first hole section (211); and the lower end of the spring (4) is located in the second hole section (212) and is in contact with a bottom surface of the second hole section (212).

19. The high-temperature and high-pressure resistant composite checkvalve according to claim 18, wherein the guiding rod (7) comprises a main rod body (71) and a support seat (72) provided at an upper end of the main rod body (71); the support seat (72) is used for supporting the special concrete layer (6); and the spring (4) is sleeved on the main rod body (71), and an upper end of the spring (4) is in contact with the support seat (72).

20. The high-temperature and high-pressure resistant composite check valve according to claim 1, wherein the main rod body (71) comprises a first rod section (711) and a second rod section (712) that are sequentially connected in a direction away from the support seat (72); and an outer diameter of the first rod section (711) is greater than an outer diameter of the second rod section (712).

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