A high temperature gas cooled reactor primary circuit nuclear grade ball valve

Abstract

The application discloses a high-temperature gas cooled reactor primary loop nuclear grade ball valve, belongs to the field of ball valve design, and relates to a high-temperature gas cooled reactor primary loop nuclear grade ball valve which comprises a valve shell and a valve cover, the valve cover and the valve shell are provided with a cavity for placing a valve core assembly between the valve cover and the valve shell, the valve core assembly comprises a valve cage and a ball, and a pressing sleeve is further arranged between the valve cage and the ball, and elastic members are arranged between the pressing sleeve and the valve cage and between the pressing sleeve and the ball respectively. The elastic members arranged in the valve core assembly can avoid abrasion of internal sealing members when the ball valve is operated to be opened or closed, prolong the service life of the ball valve and reduce the internal leakage rate.

Description

Technical Field

[0001] This invention relates to the field of ball valve technology, and in particular to a nuclear-grade ball valve for the primary loop of a high-temperature gas-cooled reactor. Background Technology

[0002] High-temperature gas-cooled reactors (HTGRs) are an advanced nuclear reactor design. Unlike traditional water-cooled reactors (such as pressurized water reactors and boiling water reactors), they use gas (usually helium) instead of water to cool the nuclear fuel and regulate the reactor temperature. In the backflush filter piping of the fuel loading and unloading system in HTGR nuclear power plants, the medium is high-pressure helium, which carries radiation. Ball valves are needed to control the flow of high-pressure helium in the piping. These ball valves must be able to operate in high-temperature environments and ensure reliable sealing and control. Since an HTGR is a nuclear reactor system, safety and prevention of radiation leakage are paramount. Ball valves must possess excellent sealing performance to ensure that gas does not leak into the environment. Reducing internal leakage is a crucial measure to improve the sealing performance of ball valves, and internal leakage is generally caused by wear of internal seals. Based on this, a ball valve with good wear resistance and a long service life is designed. Summary of the Invention

[0003] In view of the problems existing in the primary loop nuclear-grade ball valve of the high-temperature gas-cooled reactor mentioned above, this invention is proposed.

[0004] Therefore, the problem to be solved by this invention is how to solve the problem of easy wear of the internal seals of the ball valve, which leads to internal leakage.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a nuclear-grade ball valve for the primary loop of a high-temperature gas-cooled reactor, comprising a valve body and a valve cover, wherein a cavity for placing a valve core assembly is provided between the valve cover and the valve body; the valve core assembly comprises a valve cage and a ball, wherein a pressure sleeve is further provided between the valve cage and the ball; and elastic elements are respectively provided between the pressure sleeve and the valve cage, and between the pressure sleeve and the ball.

[0006] As a preferred embodiment of the nuclear-grade ball valve for the primary loop of the high-temperature gas-cooled reactor described in this invention, wherein: the inner wall of the cavity inside the valve housing is wedge-shaped, the outer wall of the valve cage is also wedge-shaped, the valve cage slides with the inner wall of the valve housing, a first sealing surface is provided on the inner side of the valve cage, and at least one first sealing groove is provided on the first sealing surface, the opening angle of the first sealing groove being ω.

[0007] As a preferred embodiment of the nuclear-grade ball valve for the primary loop of the high-temperature gas-cooled reactor described in this invention, the ball is disposed inside the valve cage and a support platform is symmetrically disposed on the ball, and a valve stem seat is also disposed on the support platform, the valve stem seat being rotatably engaged with the valve cage through a sealed bearing.

[0008] As a preferred embodiment of the nuclear-grade ball valve for the primary loop of the high-temperature gas-cooled reactor described in this invention, the end face of the support platform near the valve stem seat is a second sealing surface, a hemispherical groove is provided on the second sealing surface, the hemispherical grooves are evenly distributed, and a second sealing groove is also provided on the second sealing surface, the cross-sectional shape of the second sealing groove is a right trapezoid.

[0009] As a preferred embodiment of the nuclear-grade ball valve for the primary loop of the high-temperature gas-cooled reactor of the present invention, wherein: the pressure sleeve is disposed between the valve cage and the ball, the pressure sleeve is annular and slides with the valve cage, the pressure sleeve is divided into a main sealing end and a secondary sealing end, the main sealing end can fit against the surface of the ball, the secondary sealing end is divided into a third sealing surface and a fourth sealing surface, a hemisphere is provided on the third sealing surface, and the hemisphere can fit with the hemispherical groove.

[0010] As a preferred embodiment of the nuclear-grade ball valve for the primary loop of the high-temperature gas-cooled reactor described in this invention, a gap is provided between the third sealing surface and the second sealing surface, and the second sealing groove is also provided on the third sealing surface.

[0011] As a preferred embodiment of the nuclear-grade ball valve for the primary loop of the high-temperature gas-cooled reactor described in this invention, the fourth sealing surface has a gap with the first sealing surface, and at least one first sealing groove is also provided on the fourth sealing surface.

[0012] In a preferred embodiment of the nuclear-grade ball valve for the primary loop of the high-temperature gas-cooled reactor described in this invention, the elastic element includes a first corrugated spring disposed between the first sealing surface and the fourth sealing surface; the elastic element further includes a second corrugated spring disposed between the second sealing surface and the third sealing surface.

[0013] As a preferred embodiment of the nuclear-grade ball valve of the primary loop of the high-temperature gas-cooled reactor described in this invention, wherein: the opening angle of the protrusion of the first corrugated spring under normal conditions is θ, θ < ω, and the protrusion of the first corrugated spring is placed in the first sealing groove.

[0014] As a preferred embodiment of the nuclear-grade ball valve for the primary loop of the high-temperature gas-cooled reactor described in this invention, a washer is also fixedly provided at one end of the second corrugated spring, and the cross-sectional shape of the washer is an isosceles trapezoid.

[0015] The beneficial effects of this invention are as follows: By setting the internal elastic element of the valve core assembly, this invention can prevent the wear of the internal seals when the ball valve is opened and closed, thereby extending its service life and reducing the internal leakage rate. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0017] Figure 1 This is a diagram showing the external structure of the nuclear-grade ball valve in the primary loop of a high-temperature gas-cooled reactor.

[0018] Figure 2 This is an exploded view of the internal structure of the nuclear-grade ball valve in the primary loop of a high-temperature gas-cooled reactor.

[0019] Figure 3 This is an exploded view of the internal structure of the valve cage of the primary loop nuclear-grade ball valve in a high-temperature gas-cooled reactor.

[0020] Figure 4 This is a cross-sectional view of the overall structure of the nuclear-grade ball valve in the primary loop of a high-temperature gas-cooled reactor.

[0021] Figure 5 This is a cross-sectional view of the internal structure of the valve cage of the primary loop nuclear-grade ball valve in a high-temperature gas-cooled reactor.

[0022] Figure 6 This is a cross-sectional view of the valve cage structure of the primary loop nuclear-grade ball valve in a high-temperature gas-cooled reactor.

[0023] Figure 7 for Figure 6 Enlarged view of the structure at point A in the middle.

[0024] Figure 8 This is a cross-sectional view of the pressure sleeve structure of the primary loop nuclear-grade ball valve in a high-temperature gas-cooled reactor.

[0025] Figure 9 This is a diagram of the spherical structure of the primary loop nuclear-grade ball valve in a high-temperature gas-cooled reactor.

[0026] Figure 10 This is a cross-sectional view of the spherical structure of the primary loop nuclear-grade ball valve in a high-temperature gas-cooled reactor.

[0027] Figure 11 for Figure 10 Enlarged view of the structure at point B.

[0028] Figure 12 This is a cross-sectional view of the fit between the elastic element and other components in the primary loop ball valve of a high-temperature gas-cooled reactor. Detailed Implementation

[0029] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0030] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0031] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places throughout this specification does not necessarily refer to the same embodiment, nor is it an embodiment that is mutually exclusive, either alone or selectively, with other embodiments.

[0032] Example 1

[0033] Reference Figure 1 and Figure 2 This is the first embodiment of the present invention, which provides a nuclear-grade ball valve for the primary loop of a high-temperature gas-cooled reactor. The high-temperature gas-cooled reactor primary loop nuclear-grade ball valve includes a valve body 100, a valve cover 200, and a valve core assembly 300.

[0034] Specifically, the valve body 100 is integrally cast and can be connected to the valve cover 200 via a flange. The inner walls of the valve body 100 are wedge-shaped on opposite sides, and the valve cage 301 is composed of two symmetrical parts with wedge-shaped side walls. Therefore, when the valve cage 301 is placed into the valve body 100, the two parts of the valve cage 301 are squeezed by the inner walls of the valve body 100, which not only improves the seal between the valve cage 301 and the valve body 100, but also provides clamping force for the two parts of the valve cage 301, thereby ensuring the sealing performance of the valve cage 301.

[0035] Preferably, two pressure sleeves 303 are symmetrically arranged. Under the action of the elastic element 304, the pressure sleeves 303 are tightly attached to the surface of the ball 302 to ensure the internal sealing of the ball valve. When the ball 302 begins to rotate, the pressure sleeves 303 will temporarily separate from the ball 302. Only when the ball 302 has rotated to its final position, i.e., in the open and closed states, will the pressure sleeves 303 re-adhere to the ball 302, thus ensuring a seal. This reduces the friction time between the pressure sleeves 303 and the ball 302, thereby extending their service life. In addition, the elastic element 304 provides pre-tightening force to the pressure sleeves 303, which also increases the sealing performance.

[0036] Example 2

[0037] Reference Figures 2 to 12 This is the second embodiment of the present invention, which is based on the previous embodiment.

[0038] Specifically, a first sealing surface 301a is provided on the inner side of the valve cage 301, and at least one first sealing groove 301a-1 is provided on the first sealing surface 301a. The opening angle of the first sealing groove 301a-1 is ω. The first sealing surface 301a is the surface that abuts against the outer surface of the pressure sleeve 303, that is, in this embodiment, the first sealing surface 301a is the surface in the horizontal direction of the inner wall of the valve cage 301. Correspondingly, the surface in the horizontal direction of the outer surface of the pressure sleeve 303 is the third sealing surface 303b-1. Both the first sealing surface 301a and the third sealing surface 303b-1 are provided with a plurality of first sealing grooves 301a-1, and the position of the first sealing groove 301a-1 corresponds to the protrusion of the first corrugated spring 304a. The opening angle of the first sealing groove 301a-1 is 140° < ω < 150°, and in this embodiment, ω = 143°.

[0039] Preferably, the ball 302 is disposed inside the valve cage 301, and a support platform 302a is symmetrically arranged on the ball 302. A valve stem seat 302b is also provided on the support platform 302a, and the valve stem seat 302b is rotatably engaged with the valve cage 302 via a sealed bearing 302c. The support platform 302a on the ball 302 is cylindrical, and the valve stem seat 302b is coaxial with the support platform 302a. A groove is provided at the end of the valve stem seat 302b for mounting the valve stem.

[0040] Preferably, the end face of the bearing platform 302a near the valve stem seat 302b is the second sealing surface 302a-1. Hemispherical grooves 302a-2 are provided on the second sealing surface 302a-1, and these grooves are evenly distributed. In this embodiment, four hemispherical grooves 302a-2 are provided, spaced 90 degrees apart in a circular pattern. Correspondingly, hemispheres 303b-3 are provided on the third sealing surface 303b-1 of the pressure sleeve 303. In this embodiment, four hemispheres 303b-3 are also provided, spaced 90 degrees apart in a circular pattern. In other words, under normal conditions, the hemisphere 303b-3 is placed within the hemisphere groove 302a-2. When the ball 302 rotates, i.e., when the support platform 302a rotates, the hemisphere 303b-3 on the pressure sleeve 303 slides out of the hemisphere groove 302a-2 on the support platform 302a. This means the pressure sleeve 303 is lifted, and the main sealing end 303a on the pressure sleeve 303 temporarily separates from the surface of the ball 302. Only after the support platform 302a rotates 90 degrees will the hemisphere 303b-3 on the pressure sleeve 303 fall back into the hemisphere groove 302a-2, the pressure sleeve 303 reset, and the main sealing end 303a re-adhere to the hemisphere 303b-3. This reduces friction when the ball 302 rotates, extending the service life of the ball valve.

[0041] Preferably, a first bellows spring 304a is located between the first sealing surface 301a and the fourth sealing surface 303b-2. The protrusion opening angle of the first bellows spring 304a in its normal state is θ, where θ < ω. In this embodiment, θ = 104°, and the protrusion of the first bellows spring 304a is positioned within the first sealing groove 301a-1. The first bellows spring 304a is elastic, providing clamping force to the pressure sleeve 303 while also sealing between components. Furthermore, since θ < ω, when the first bellows spring 304a is compressed, it gradually flattens, increasing the protrusion opening angle and fitting into the first sealing groove 301a-1. That is, when the main sealing end 303a on the pressure sleeve 303 moves away from the ball 302, the protrusion of the first bellows spring 304a fits into the first sealing groove 301a-1, thereby achieving a better sealing effect and preventing internal leakage inside the ball valve.

[0042] Preferably, a second sealing groove 302a-3 is also provided on the second sealing surface 302a-1 and the third sealing surface 303b-1. The two second sealing grooves 302a-3 with right-angled trapezoidal cross-sections can be combined to form an annular groove with a complete isosceles trapezoidal cross-section. A second corrugated spring 304b is also installed between the second sealing surface 302a-1 and the third sealing surface 303b-1, and a washer 304b-1 is fixed on the outer ring of the second corrugated spring 304b. The cross-sectional shape of the washer 304b-1 is an isosceles trapezoid, but its size is smaller than the cross-sectional shape of the second sealing groove 302a-3. Therefore, when the main sealing end 303a on the pressure sleeve 303 moves away from the ball 302, the second corrugated spring 304b will contract. At this time, the outer ring of the second corrugated spring 304b will pull the washer 304b-1 to move towards the center. Since the cross-sections of the washer 304b-1 and the second sealing groove 302a-3 are both wedge-shaped, the washer 304b-1 will seal the second sealing surface 302a-1 and the third sealing surface 303b-1 more tightly.

[0043] Based on the above, the working principle of this invention is as follows:

[0044] When the ball 302 begins to rotate, the pressure sleeve 303, which is in close contact with the surface of the ball 302, moves up and down respectively. At the same time, the first corrugated spring 304a is compressed and begins to store force. The main sealing end 303a on the pressure sleeve 303 will temporarily separate from the surface of the ball 302. When the ball 302 rotates to its final position, the pressure sleeve 303 will reset under the action of the first corrugated spring 304a, and the main sealing end 303a will re-adhere to the ball 302, maintaining a seal. This prevents frictional wear on the main sealing end 303a when the ball 302 rotates, extending its service life.

[0045] However, when the pressure sleeve 303 moves up and down respectively, fluid will also flow out from the gap between the main sealing end 303a and the ball 302, which may lead to leakage from the sealing bearing 302c. If this is not restricted, it will increase the internal leakage rate of the valve core, and thus lead to external leakage. Therefore, when the pressure sleeve 303 moves to both sides, the first bellows spring 304a is also compressed, and the first bellows spring 304a gradually "flattens" until it fills the entire first sealing groove 301a-1. On the other hand, when the main sealing end 303a on the pressure sleeve 303 moves away from the ball 302, the second bellows spring 304b will contract. At this time, the outer ring of the second bellows spring 304b will pull the washer 304b-1 to move towards the center. Since the cross-section of the washer 304b-1 and the second sealing groove 302a-3 are both wedge-shaped, the washer 304b-1 will seal the second sealing surface 302a-1 and the third sealing surface 303b-1 more tightly. This not only extends the length of the fluid flow path but also increases the tortuosity of the fluid flow path, thus achieving a better sealing effect and reducing the internal leakage rate of the valve core.

[0046] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A nuclear-grade ball valve for the primary loop of a high-temperature gas-cooled reactor, characterized in that: include, A valve housing (100) and a valve cover (200) are provided, with a cavity for placing a valve core assembly (300) between the valve cover (200) and the valve housing (100); The valve core assembly (300) includes a valve cage (301) and a ball (302), and a pressure sleeve (303) is also provided between the valve cage (301) and the ball (302). Elastic elements (304) are provided between the pressure sleeve (303) and the valve cage (301), and between the pressure sleeve (303) and the ball (302). The valve cage (301) has a first sealing surface (301a) on its inner side, and at least one first sealing groove (301a-1) is provided on the first sealing surface (301a). The ball (302) is disposed inside the valve cage (301) and a support platform (302a) is symmetrically disposed on the ball (302). A valve stem seat (302b) is also disposed on the support platform (302a). The end face of the support platform (302a) near the valve stem seat (302b) is a second sealing surface (302a-1). A hemispherical groove (302a-2) is provided on the second sealing surface (302a-1). The hemispherical groove (302a-2) is evenly distributed. A second sealing groove (302a-3) is also provided on the second sealing surface (302a-1). The cross-sectional shape of the second sealing groove (302a-3) is a right trapezoid. The pressure sleeve (303) is disposed between the valve cage (301) and the ball (302). The pressure sleeve (303) is annular and slides with the valve cage (301). The pressure sleeve (303) is divided into a main sealing end (303a) and a secondary sealing end (303b). The main sealing end (303a) can fit against the surface of the ball (302). The secondary sealing end (303b) is divided into a third sealing surface (303b-1) and a fourth sealing surface (303b-2). A hemisphere (303b-3) is provided on the third sealing surface (303b-1). The hemisphere (303b-3) fits with the hemispherical groove (302a-2). There is a gap between the third sealing surface (303b-1) and the second sealing surface (302a-1), and the second sealing groove (302a-3) is also provided on the third sealing surface (303b-1). There is a gap between the fourth sealing surface (303b-2) and the first sealing surface (301a), and at least one first sealing groove (301a-1) is also provided on the fourth sealing surface (303b-2). The elastic element (304) includes a first corrugated spring (304a) disposed between the first sealing surface (301a) and the fourth sealing surface (303b-2). The elastic element (304) further includes a second corrugated spring (304b) disposed between the second sealing surface (302a-1) and the third sealing surface (303b-1).

2. The nuclear-grade ball valve for the primary loop of a high-temperature gas-cooled reactor as described in claim 1, characterized in that: The inner wall of the cavity in the valve housing (100) is wedge-shaped, and the outer wall of the valve cage (301) is also wedge-shaped. The valve cage (301) slides with the inner wall of the valve housing (100), and the opening angle of the first sealing groove (301a-1) is ω.

3. The nuclear-grade ball valve for the primary loop of a high-temperature gas-cooled reactor as described in claim 2, characterized in that: The valve stem seat (302b) is rotatably engaged with the valve cage (301) via a sealed bearing (302c).

4. The nuclear-grade ball valve for the primary loop of a high-temperature gas-cooled reactor as described in claim 3, characterized in that: The protrusion opening angle of the first corrugated spring (304a) under normal conditions is θ, θ < ω, and the protrusion of the first corrugated spring (304a) is placed in the first sealing groove (301a-1).

5. The nuclear-grade ball valve for the primary loop of a high-temperature gas-cooled reactor as described in claim 4, characterized in that: A washer (304b-1) is also fixedly provided at one end of the second corrugated spring (304b), and the cross-sectional shape of the washer (304b-1) is an isosceles trapezoid.

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