Spigot contact sealing structure of valve body and valve cover and mounting method

Abstract

The invention relates to a spigot contact sealing structure of a valve body and a valve cover and an installation method, the structure comprises the valve body, the valve cover and a sealing ring, the top of the valve body is provided with a valve seat, the upper surface of the valve seat is provided with an annular spigot groove, a spigot check block is formed between the spigot groove and an inner ring of the valve seat, and the spigot check block is provided with a spigot hole. The valve cover is provided with a circular-ring-shaped protrusion matched with the spigot groove, the sealing ring and the circular-arc-shaped protrusion are both located in the spigot groove, and the sealing ring is evenly compressed by the circular-arc-shaped protrusion. Compared with the prior art, the invention has the advantages of strong working condition fluctuation resistance, high structural stability, prolonged service life, low maintenance cost and the like.

Description

Technical Field

[0001] This invention relates to the field of valve structure, and in particular to a stop-sealing structure and installation method for a valve body and valve cover. Background Technology

[0002] Currently, the valve cover of most steam extraction check valves uses a flat surface with a graphite composite gasket to achieve a sealed connection between the valve seat and the valve cover. However, the medium flowing inside the valve is prone to direct contact and erosion with the flat surface of the sealing ring and the graphite composite gasket, which leads to accelerated aging of the sealing ring, reduced sealing performance, and serious gasket damage and leakage problems.

[0003] For example, the invention disclosed in CN203940050U discloses a high-pressure corrosion-resistant oblique-flap type hard self-sealing check valve for nuclear power island core. It includes a valve body, valve seat, valve disc, valve cover, self-sealing ring, gasket, four-opening ring, lifting ring, and cover plate. The valve disc is installed in the middle of the valve body, and the valve seat is installed between the valve disc and the valve body. The valve cover is installed at the upper end of the valve body. The self-sealing ring, gasket, and four-opening ring are installed between the valve cover and the valve body. The self-sealing ring is pressed on the valve cover. The gasket is pressed on the upper end of the self-sealing ring. The four-opening ring is pressed on the upper end of the gasket. The cover plate is pressed on the upper end of the four-opening ring. The cover plate is fixed to the upper end of the valve cover by bolts and nuts. The lifting ring is installed in the middle of the upper end of the cover plate. The valve disc is fixed to the valve body by a pin passing through the upper end of the valve disc.

[0004] In the above solution, the sealing ring is directly pressed between the valve cover and the valve body. The medium flowing inside the valve can easily erode the sealing ring, leading to accelerated aging and a risk of leakage. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects of the existing technology, which uses a flat surface plus graphite composite gasket for sealing, which leads to the medium contacting and eroding the gasket, accelerating the aging rate, and reducing the sealing performance. This invention provides a stop contact sealing structure and installation method for valve body and valve cover.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] A valve body and valve cover stop contact sealing structure includes a valve body, a valve cover and a sealing ring. The valve body has a valve seat on its top, and the upper surface of the valve seat has an annular stop groove. The stop groove and the inner ring of the valve seat form a stop block. The valve cover has an annular protrusion that mates with the stop groove. The sealing ring and the arc-shaped protrusion are both located in the stop groove. The sealing ring is uniformly compressed by the arc-shaped protrusion.

[0008] Furthermore, the cross-section of the stop groove is rectangular, and the depth of the stop groove is interference-fitted with the sum of the thicknesses of the sealing ring and the annular protrusion.

[0009] Further, the stopper block is in contact with the surface of the valve cover, forming a mechanical hard sealing barrier between the valve body and the valve cover.

[0010] Further, the flow direction of the medium in the valve body is perpendicular to the plane where the stopper groove and the stopper block are located, so as to reduce the direct scouring of the flowing medium to the sealing surface where the sealing ring is located.

[0011] Further, the stopper contact sealing structure of the valve body and the valve cover is used for a steam valve.

[0012] Further, the top of the valve seat is also provided with a bolt hole for connecting the valve cover, and the stopper groove is located between the bolt hole and the inner ring of the valve seat.

[0013] Further, the sealing ring is a graphite composite gasket.

[0014] The application also provides a mounting method of the stopper contact sealing structure of the valve body and the valve cover as described above, comprising the following steps:

[0015] Obtaining the valve body, the valve cover and the sealing ring to be mounted;

[0016] According to the size of the sealing ring, a stopper groove is processed on the valve seat of the valve body, and a gap between the stopper groove and the inner ring of the valve seat is reserved to form a stopper block; a circular annular protrusion is processed on the valve cover;

[0017] The sealing ring is placed in the stopper groove on the valve seat, and then the valve cover is placed on the valve seat, and the circular annular protrusion of the valve cover is matched with the stopper groove to complete the alignment;

[0018] The valve seat and the valve cover are fixed by screws to realize the assembly of the sealing ring and the valve cover on the valve body.

[0019] Further, the method further comprises:

[0020] During the operation of the valve body, the surface defects of the stopper groove and the stopper block in the valve body are checked, and if there are surface defects, the surface defects are repaired by grinding or surfacing.

[0021] Further, the processing method of the stopper groove adopts turning processing.

[0022] Compared with the prior art, the application has the following advantages:

[0023] (1) Strong ability to resist working condition fluctuation:

[0024] Temperature alternation: the stopper structure limits the displacement caused by thermal expansion and cold contraction, avoiding the failure of plane sealing due to flange warping.

[0025] Pressure impact: the mechanical interlocking design can resist water hammer or instantaneous pressure fluctuation to prolong the service life

[0026] Reducing gasket wear: the shoulder bears part of the load, and the gasket only needs to compensate for microscopic unevenness, and the aging speed is slow.

[0027] Anti-washing design: the medium flow direction is perpendicular to the shoulder, reducing the direct washing of high-speed fluid on the sealing surface (especially suitable for steam valves).

[0028] (2) High structural stability:

[0029] Automatic positioning: the shoulder guides the valve cover and the valve body to be accurately centered, avoiding the deflection caused by uneven bolt pre-tightening force.

[0030] Anti-vibration loosening: the concave-convex engagement structure prevents bolt loosening caused by vibration.

[0031] (3) Prolonging service life:

[0032] Reducing gasket wear: the shoulder bears part of the load, and the gasket only needs to compensate for microscopic unevenness, and the aging speed is slow.

[0033] Anti-washing design: the medium flow direction is perpendicular to the shoulder, reducing the direct washing of high-speed fluid on the sealing surface (especially suitable for steam valves).

[0034] (4) Low maintenance cost:

[0035] Reusability: the metal shoulder surface can be repaired (grinding, hardfacing), and once the flat sealing flange is deformed, it needs to be replaced as a whole.

[0036] Convenient maintenance: when reinstalled after disassembly, the shoulder can be quickly aligned, reducing manual adjustment time. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 A structure diagram of a valve body valve cover shoulder contact sealing structure provided in an embodiment of the present application;

[0038] Figure 2 A local structure diagram of a valve body valve cover shoulder contact sealing structure provided in an embodiment of the present application;

[0039] In the figure, 1 is a valve body, 2 is a valve cover, 3 is a sealing ring, 4 is a valve seat, 5 is a shoulder groove, 6 is a shoulder stopper, and 7 is a circular ring-shaped protrusion. DETAILED DESCRIPTION

[0040] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will be combined with the accompanying drawings for the embodiments of the present application to make a clear and complete description of the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0041] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.

[0042] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0043] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when the product of the present application is usually placed, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0044] It should be noted that the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0045] In addition, the terms "horizontal", "vertical" and the like do not mean that the components must be absolutely horizontal or vertical, but can be slightly inclined. For example, "horizontal" only means that its direction is relatively more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0046] Embodiment 1

[0047] As Figure 1 and Figure 2As shown, this embodiment provides a stop-contact sealing structure for a valve body and valve cover, including a valve body 1, a valve cover 2, and a sealing ring 3. The top of the valve body 1 is provided with a valve seat 4, and the upper surface of the valve seat 4 is provided with an annular stop groove 5. The stop groove 5 and the inner ring of the valve seat 4 form a stop block 6. The valve cover 2 is provided with an annular protrusion 7 that cooperates with the stop groove 5. The sealing ring 3 and the arc-shaped protrusion are both located in the stop groove 5, and the sealing ring 3 is uniformly compressed by the arc-shaped protrusion.

[0048] This solution improves the planar contact between the valve cover and the valve body by changing it to a stop contact form. The valve body is machined with grooves, and the valve cover is machined with convex surfaces.

[0049] The stop block 6 contacts the surface of the valve cover 2, forming a mechanical hard seal barrier between the valve body 1 and the valve cover 2.

[0050] This achieves a double sealing mechanism:

[0051] Mechanical hard seal: The concave and convex structure of the stop, namely the stop block 6, forms the first barrier, reducing the reliance on soft sealing ring gaskets.

[0052] Gasket-assisted sealing: The gasket is uniformly compressed within the stop groove 5, resulting in a longer leakage path and a labyrinth effect.

[0053] Preferably, the cross-section of the stop groove 5 is rectangular, and the depth of the stop groove 5 is interference-fitted with the sum of the thicknesses of the sealing ring 3 and the annular protrusion 7.

[0054] This allows the sealing ring to be securely fixed in the stop groove 5 by the annular protrusion 7 of the valve cover 2, thus achieving a seal.

[0055] The flow direction of the medium inside the valve body 1 is perpendicular to the plane where the stop groove 5 and the stop block 6 are located, so as to reduce the direct scouring of the sealing surface where the sealing ring 3 is located by the flowing medium, which is especially suitable for steam valves.

[0056] The top of the valve seat 4 is also provided with bolt holes for connecting the valve cover 2, and the stop groove 5 is located between the bolt holes and the inner ring of the valve seat 4.

[0057] Multiple bolt holes are evenly distributed along the outer ring of valve seat 4.

[0058] In this embodiment, the sealing ring 3 is a graphite composite gasket.

[0059] This embodiment also provides an installation method for the valve body and valve cover stop contact sealing structure as described above, including the following steps:

[0060] Obtain the valve body 1, valve cover 2, and sealing ring 3 to be installed;

[0061] According to the size of the sealing ring 3, a stop groove 5 is machined on the valve seat 4 of the valve body 1, and a gap between the stop groove 5 and the inner circle of the valve seat 4 is reserved to form a stop block 6; a circular annular protrusion 7 is machined on the valve cover 2;

[0062] The sealing ring 3 is placed in the stop groove 5 on the valve seat 4; then the valve cover 2 is placed on the valve seat 4, and the circular annular protrusion 7 of the valve cover 2 matches the stop groove 5 to complete the alignment;

[0063] The valve seat 4 and the valve cover 2 are fixed by screws to realize the assembly of the sealing ring 3 and the valve cover 2 on the valve body 1.

[0064] Preferably, the method further comprises:

[0065] During the operation of the valve body 1, the stop groove 5 and the stop block 6 in the valve body 1 are subjected to surface defect inspection, and if there is a surface defect, the surface defect is repaired by grinding or surfacing.

[0066] When the stop structure is damaged, the metal stop surface can be ground and surfaced for repair, and once the flat sealing flange is deformed, it needs to be replaced as a whole.

[0067] The machining method of the stop groove 5 adopts turning machining.

[0068] In the embodiment, the two-draw and four-draw check door cover gasket is designed as φ406*368*3 and φ344*312*3, respectively, for correct installation of the two-draw and four-draw check door cover gasket.

[0069] When the stop structure is machined, the turning flatness is ≤0.03mm, the perpendicularity to the center line of the valve body is ≤0.05mm, the stop gap is 0.10-0.20mm, and the surface roughness reaches the Ra0.8μm level.

[0070] The above describes the preferred embodiment of the application in detail. It should be understood that those skilled in the art can make many modifications and changes without creative labor according to the concept of the application. Therefore, any technical solution obtained by logical analysis, reasoning or limited experiment based on the prior art according to the concept of the application should be within the protection scope defined by the claims.

Claims

1. A valve body / valve cover stop contact sealing structure, characterized in that, The valve includes a valve body (1), a valve cover (2), and a sealing ring (3). The valve body (1) has a valve seat (4) on its top. The upper surface of the valve seat (4) has an annular groove (5). The groove (5) and the inner ring of the valve seat (4) form a stop block (6). The valve cover (2) has an annular protrusion (7) that matches the groove (5). The sealing ring (3) and the arc-shaped protrusion are both located in the groove (5). The sealing ring (3) is uniformly compressed by the arc-shaped protrusion.

2. The valve body and valve cover stop contact sealing structure according to claim 1, characterized in that, The cross-section of the stop groove (5) is rectangular, and the depth of the stop groove (5) is interference-fitted with the sum of the thicknesses of the sealing ring (3) and the annular protrusion (7).

3. The valve body and valve cover stop contact sealing structure according to claim 1, characterized in that, The stop block (6) contacts the surface of the valve cover (2) to form a mechanical hard seal barrier between the valve body (1) and the valve cover (2).

4. The valve body and valve cover stop contact sealing structure according to claim 1, characterized in that, The flow direction of the medium inside the valve body (1) is perpendicular to the plane where the stop groove (5) and the stop block (6) are located, so as to reduce the direct scouring of the sealing surface where the sealing ring (3) is located by the flowing medium.

5. The valve body and valve cover stop contact sealing structure according to claim 4, characterized in that, The valve body and valve cover stop contact sealing structure is used for steam valves.

6. The valve body and valve cover stop contact sealing structure according to claim 1, characterized in that, The valve seat (4) is also provided with a bolt hole for connecting the valve cover (2) at the top, and the stop groove (5) is located between the bolt hole and the inner ring of the valve seat (4).

7. The valve body and valve cover stop contact sealing structure according to claim 1, characterized in that, The sealing ring (3) is a graphite composite gasket.

8. A method for installing a valve body / valve cover stop contact sealing structure as described in any one of claims 1-7, characterized in that, Includes the following steps: Obtain the valve body (1), valve cover (2), and sealing ring (3) to be installed; According to the size of the sealing ring (3), a stop groove (5) is machined on the valve seat (4) of the valve body (1), and a gap is reserved between the stop groove (5) and the inner ring of the valve seat (4) to form a stop block (6); a circular protrusion (7) is machined on the valve cover (2); Place the sealing ring (3) in the stop groove (5) on the valve seat (4); then place the valve cover (2) on the valve seat (4), and match the annular protrusion (7) of the valve cover (2) with the stop groove (5) to complete the alignment; The valve seat (4) and valve cover (2) are fixed with screws to achieve the assembly of the sealing ring (3) and valve cover (2) on the valve body (1).

9. The method according to claim 8, characterized in that, The method further includes: During the operation of the valve body (1), the surface defects of the stop groove (5) and stop block (6) in the valve body (1) are inspected. If surface defects are found, they are repaired by grinding or welding.

10. The method according to claim 8, characterized in that, The stop groove (5) is machined by turning.

Images