Spray valve structure capable of adjusting force of disc spring according to opening degree and method thereof

Abstract

The application discloses a kind of spray valve structure and method of adjusting disc spring stress according to opening degree, belong to valve field.The valve core assembly of the device is matched with valve stem by spline;Valve seat assembly is matched with valve body to realize vertical direction fixation, and linear seal is formed by the disc spring of setting pre-tightening force and valve core in horizontal direction, and the baffle structure of valve seat assembly and the baffle structure of valve body exist face coincidence;Valve core assembly drives valve seat assembly to rotate by bevel gear structure, and the coincidence area of the baffle structure of valve seat assembly and the baffle structure of valve body increases, and the flow area of medium increases.The application can change the fluid force difference suffered by both sides of disc spring in valve operating process according to opening degree, prevent small opening degree under disc spring inlet side fluid force too large from being extruded and separated from valve body to cause valve internal leakage failure, and also ensure that fluid force pressure drop is reduced to prevent disc spring outlet side fluid force too large from being extruded and separated from valve seat to cause valve core valve seat sealing failure.

Description

Technical Field

[0001] This invention belongs to the field of valve structure design, and specifically relates to a spray valve structure and method that can adjust the force on the disc spring according to the opening degree. Background Technology

[0002] The pressurizer spray valve is located in the pressurizer spray system, with its inlet connected to the reactor cold section and its outlet connected to the pressurizer. Its main function is to regulate the flow rate of primary loop cold section water injected into the upper steam space of the pressurizer, thereby regulating the condensation in the upper steam space and thus controlling the pressurizer pressure. The pressurizer pressure control system controls the opening and closing of the pressurizer spray valve. When the pressurizer pressure increases, the pressure control system sends a signal to open the pressurizer spray valve, allowing the "cold fluid" from the cold section to be sprayed into the pressurizer's steam space through the spray valve and spray nozzles, causing the pressurizer pressure to decrease. The importance of the pressurizer spray valve is evident; as the primary device for regulating the pressure in the primary loop of a pressurized water reactor nuclear power plant, its performance and reliability are of paramount importance.

[0003] The normal operating state of the spray valve during actual operation is as follows: Figure 5 As shown in (a), the disc spring is subjected to fluid forces on both sides, but a disc spring fracture occurred during operation. Research revealed that in a conventional structure, the force on the inlet side is close to the inlet pressure, and the pressure on the outlet side is close to the outlet pressure. At a small opening, the fluid experiences a large pressure difference due to the significant throttling effect of the valve core. This means that the pressure difference across the disc spring is large (greater on the inlet side than the outlet side), which may lead to issues such as… Figure 5 In the scenario shown in (b), the disc spring detaches from the valve body, causing internal leakage. The disc spring also fails due to fatigue from the reciprocating motion of the fluid. Therefore, it is necessary to reduce the pressure on the disc spring inlet side when the valve is open only slightly. However, at a large opening, the valve flow is close to straight pipe flow, and the pressure difference between the inlet and outlet is very small. That is, the pressure difference across the disc spring is also very small, so it is not necessary to reduce the pressure on the disc spring inlet side at a large opening. If the pressure on the disc spring inlet side is reduced at this time, then... Figure 5 As shown in (c), the disc spring may disengage from the valve seat due to the pressure on the inlet side being significantly greater than the pressure on the outlet side. Therefore, there is an urgent need to provide a spray valve structure and method that can adjust the force on the disc spring according to the opening degree. Summary of the Invention

[0004] The purpose of this invention is to overcome the defects in the prior art and to provide a spray valve structure and method that can adjust the force on the disc spring according to the opening degree.

[0005] The specific technical solution adopted in this invention is as follows:

[0006] The first aspect of the present application provides a spray valve structure capable of adjusting the force of a disc spring according to the opening degree, comprising a lower flange, a lower fixed bushing, a disc spring, an upper fixed bushing and a valve rod, specifically, the present application further comprises a valve body with a second baffle, a valve core assembly with a first bevel gear and a valve seat assembly with a second bevel gear.

[0007] The bottom of the valve body is connected with a lower flange, and the inner wall of the inlet end is circumferentially provided with a plurality of second baffles protruding inward, all of which are arc strip structures capable of forming concentric circles.

[0008] The valve core assembly comprises a first bevel gear, a ball core and a positioning shaft arranged coaxially in sequence; the first bevel gear is fixedly connected with the ball core and is detachably fixedly connected with the bottom of the valve rod, and the valve rod is rotatably sleeved in the upper fixed bushing; the ball core and the positioning shaft are detachably fixedly connected, and the positioning shaft is rotatably sleeved in the lower fixed bushing in the valve body.

[0009] The valve seat assembly comprises a second bevel gear, a valve seat and a first baffle; the valve seat is clamped on the inlet end of the valve body and can be axially fixed, and the horizontal direction forms a linear seal with the ball core through the disc spring with a set pre-tightening force; the valve seat is fixedly connected at the end with the second bevel gear capable of meshing and transmitting with the first bevel gear, and the valve seat can rotate in the valve body; the outer wall of the front end of the valve seat is axially provided with a plurality of first baffles protruding outward, all of which are arc strip structures capable of forming concentric circles; the first baffles and the second baffles are arranged in front of and behind each other, and the two can have face coincidence and no coincidence area in the initial state, and the fluid pressure of the medium on the inlet side of the disc spring can be changed by adjusting the coincidence area.

[0010] As a preferred, the first bevel gear and the second bevel gear are both annular structures.

[0011] As a preferred, the valve rod is sleeved with a valve rod blowout prevention ring.

[0012] As a preferred, the valve rod can adjust the valve opening degree to 0-90° by driving the valve core assembly to rotate.

[0013] As a preferred, the connection mode of the first bevel gear with the ball core and the valve seat with the second bevel gear is welding.

[0014] As a preferred, the area of the first baffle is smaller than that of the second baffle, so as to ensure that there is always a medium passage between the two.

[0015] As a preferred, the number of the first baffles is the same as that of the second baffles.

[0016] As a preferred, the first bevel gear is connected with the valve rod, the ball core and the positioning shaft through spline fitting.

[0017] In the second aspect, the application provides a regulating method for the disc spring force adjusting spray valve structure according to the opening degree, and the method is specifically as follows:

[0018] S1: after the spray valve is opened at a small opening degree, the valve rod drives the valve core assembly to rotate, the V-shaped notch area of the ball core enters the flow-through area of the valve seat assembly, the medium enters the valve body through the gap between the valve core assembly and the valve seat assembly, at this time, the medium is subjected to the throttling action of the ball core to generate a large pressure drop, at this time, the medium on the inlet side needs to pass through the medium passage between the first baffle and the second baffle to reach the disc spring inlet side, that is, the medium will first be subjected to the throttling action of the medium passage and then reach the disc spring inlet side, which makes the fluid pressure on the disc spring inlet side decrease, reduces the pressure difference between the two sides due to the throttling action of the ball core, and avoids the phenomenon that the disc spring is extruded away from the valve body to cause internal leakage of the valve due to the large pressure on the inlet side;

[0019] S2: when the spray valve is continuously opened at a large opening degree, the flow state in the valve approaches straight pipe flow, the pressure difference between the inlet and the outlet decreases, the valve core assembly drives the valve seat assembly to rotate, the rotation of the valve seat assembly increases the overlapping area of the first baffle and the second baffle, and the flow-through area of the medium reaching the disc spring inlet side also continuously increases, so that the throttling action of the medium is significantly reduced, the pressure drop on the disc spring inlet side is very small, and the phenomenon that the disc spring is extruded away from the valve seat due to the excessively small pressure on the disc spring inlet side caused by the excessive throttling action of the first baffle and the second baffle at a large opening degree is avoided, so that the sealing failure of the valve core assembly and the valve seat assembly is avoided.

[0020] Compared with the prior art, the application has the following beneficial effects:

[0021] The application provides a spray valve structure and a method for adjusting the disc spring force according to the opening degree, the fluid pressure on the disc spring inlet side is changed by changing the overlapping area of the baffle structure in the valve seat assembly and the baffle structure in the valve body to change the medium flow-through area, the fluid pressure on the disc spring inlet side is reduced at a small opening degree to avoid the disc spring from being extruded away from the valve body, internal leakage of the valve is avoided, and the pressure drop of the assembly on the fluid on the disc spring inlet side is significantly reduced at a large opening degree, so that the pressure on the two sides of the disc spring is close at a large opening degree, the disc spring is avoided from being extruded away from the valve seat, and the sealing failure of the valve seat and the valve core is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a schematic diagram of the spray valve structure of the application;

[0023] Figure 2 It is a schematic diagram of the valve core assembly structure;

[0024] Figure 3 It is a schematic diagram of the valve seat assembly structure;

[0025] Figure 4 It is a schematic diagram of the valve body structure with the second baffle;

[0026] Figure 5 The diagrams show the failure of the disc spring during the operation of a conventional spray valve. Figure a represents the normal operating state, Figure b represents the failure state due to excessive inlet pressure, and Figure c represents the failure state due to excessive outlet pressure.

[0027] Figure 6 Figure 1 is a schematic diagram of the operation of the spray valve of the present invention. Figure 2 is an assembly diagram of the valve core assembly and valve seat assembly. Figure 3 shows the position of the valve body and valve seat baffle when the valve is open at a small degree. Figure 4 shows the position of the valve body and valve seat baffle when the valve is open at a large degree.

[0028] In the diagram: 1. Lower flange; 2. Valve body; 3. Lower fixed bushing; 4. Valve core assembly; 5. Valve seat assembly; 6. Disc spring; 7. Upper fixed bushing; 8. Valve stem anti-blowout ring; 9. Valve stem; 10. First bevel tooth; 11. Ball core; 12. Positioning shaft; 13. Second bevel tooth; 14. Valve seat; 15. First baffle; 16. Second baffle. Detailed Implementation

[0029] The present invention will be further described and illustrated below with reference to the accompanying drawings and specific embodiments. The technical features of each embodiment of the present invention can be combined accordingly, provided that there is no mutual conflict.

[0030] like Figure 1 As shown, this invention provides a spray valve structure that can adjust the force on the disc spring according to the opening degree. In addition to the conventional lower flange 1, lower fixed bushing 3, disc spring 6, upper fixed bushing 7, valve stem anti-blowout ring 8 and valve stem 9, the spray valve structure also includes a valve body 2 with a second baffle 16, a valve core assembly 4 with a first conical tooth 10 and a valve seat assembly 5 with a second conical tooth 13.

[0031] Compared to existing conventional spray valve structures, the structure of this invention adds a double baffle (i.e., first baffle 15 and second baffle 16) between the valve body 2 and valve seat 14, and a bevel tooth structure (i.e., first bevel tooth 10 and second bevel tooth 13) between the valve core assembly 4 and valve seat assembly 5. This arrangement allows the valve seat assembly 5 to rotate as the valve opening increases, driven by the valve core assembly 4. During rotation, the overlapping area between the first baffle 15 and the second baffle 16 continuously increases, and the flow area of ​​the medium channel continuously increases. This not only reduces the fluid pressure at the inlet side of the disc spring 6 at a small opening, but also reduces the pressure drop effect of the two baffles on the fluid as the opening increases, resulting in the fluid pressure at the inlet side of the disc spring 6 showing a trend of increasing with the opening.

[0032] The structure and connection method of each component will be explained in detail below.

[0033] The inside of the valve body 2 is hollow, the hollow inside installs each valve inner, the bottom of the valve body 2 is sealingly connected with the lower flange 1.The valve body 2 of the present application is designed with a baffle structure at the inlet end compared with the conventional valve body, as shown in Figure 4 The inner wall of the inlet end of the valve body 2 is circumferentially provided with a plurality of inwardly protruding second baffles 16, the second baffles 16 are arc-shaped strip structures and can form concentric circles.

[0034] As shown in Figure 2 The valve core assembly 4 mainly includes a first bevel gear 10, a ball core 11 and a positioning shaft 12, the first bevel gear 10, the ball core 11 and the positioning shaft 12 are coaxially arranged in sequence, that is, one end of the ball core 11 is fixedly connected with the first bevel gear 10, the opposite end of the ball core 11 is detachably fixedly connected with the positioning shaft 12. The spray valve generally adopts a ball valve structure, in order to ensure that the nearly equal percentage flow characteristic curve can be obtained, therefore, the ball core 11 structure with V-shaped notch is adopted, in actual use, the flow area of the medium can be adjusted by rotating the ball core 11 to adjust the orientation of the V-shaped notch. The first bevel gear 10 is detachably fixedly connected with the bottom of the valve stem 9, in the embodiment, the first bevel gear 10 and the valve stem 9 can be connected by spline fitting. The lower part of the valve stem 9 is sleeved in the upper fixed bushing 7 to realize the fixation in the horizontal direction, the valve stem 9 can rotate in the upper fixed bushing 7. In the embodiment, the valve stem blowout prevention ring 8 is further sleeved on the valve stem 10, which is used to fix and seal the valve stem 10 to prevent the valve stem 10 from being accidentally blown out. The ball core 11 and the positioning shaft 12 are detachably fixedly connected, the positioning shaft 12 is rotatably sleeved in the lower fixed bushing 3 in the valve body 2 to realize the fixation in the horizontal direction. In the embodiment, the ball core 11 and the positioning shaft 12 can be connected by spline fitting, the first bevel gear 10 and the ball core 11 can be fixed by welding.

[0035] As shown in Figure 3 The valve seat assembly 5 mainly includes a second bevel gear 13, a valve seat 14 and a first baffle 15. The valve seat 14 is clamped on the inlet end of the valve body 2 to realize the axial fixation, the valve seat 14 can rotate in the valve body 2. The valve seat 14 forms a linear seal with the ball core 11 in the horizontal direction through the disc spring 6. The disc spring 6 respectively contacts the valve seat assembly 5 and the valve body 2 and is provided with a certain pre-tightening force, which is used to provide the sealing force between the valve seat assembly and the ball core. In the medium flow direction, the end of the valve seat 14 is fixedly connected with the second bevel gear 13, the second bevel gear 13 can mesh and transmit with the first bevel gear 10. In the embodiment, the first bevel gear 10 and the second bevel gear 13 can all adopt annular structures, so as to realize better meshing and transmission during rotation. The outer wall of the front end of the valve seat 14 is circumferentially provided with a plurality of outwardly protruding first baffles 15, the first baffles 15 can adopt arc-shaped strip structures, all the first baffles 15 can form concentric circles. The first baffles 15 and the second baffles 16 are arranged in front of and behind each other, the two can have face coincidence and no coincidence area in the initial state, by adjusting the coincidence area, the fluid pressure of the medium on the inlet side of the disc spring 6 can be changed.

[0036] In actual use, as shown in Figure 6 (a), the valve stem 9 rotates to drive the valve core assembly 4 to rotate, and the valve opening is 0-90°. The valve core assembly 4 drives the valve seat assembly 5 to rotate through the first bevel gear 10 and the second bevel gear 13. By setting the area of the first baffle 15 to be smaller than the area of the second baffle 16, a certain medium passage is always left between the two, as shown in Figure 6 (b), in the initial state, there is no overlapping area at 0 opening, and the medium flow area is the smallest. By rotating the valve seat 14 to increase the opening, the overlapping area of the first baffle 15 and the second baffle 16 increases, and the medium passage flow area increases, as shown in Figure 6 (c).

[0037] The method for adjusting the force of the disc spring according to the opening of the spray valve with the above structure is as follows:

[0038] S1: After the spray valve is opened at a small opening, the valve stem 9 drives the valve core assembly 4 to rotate, and the V-shaped notch area enters the flow area of the valve seat assembly 5. The medium enters the inside of the valve body 2 through the gap between the valve core assembly 4 and the valve seat assembly 5, and at this time, the medium is subjected to the throttling action of the ball core 11 to produce a large pressure drop. At this time, the inlet side medium needs to pass through the medium passage between the first baffle 15 and the second baffle 16 to reach the inlet side of the disc spring 6, that is, the medium will first be subjected to the throttling action of the medium passage and then reach the inlet side of the disc spring 6, which makes the fluid pressure at the inlet side of the disc spring 6 decrease, reduces the pressure difference between the two sides due to the throttling action of the ball core 11, and avoids the phenomenon that the disc spring 6 is extruded out of the valve body 2 to cause internal leakage of the valve due to the large pressure at the inlet side.

[0039] S2: When the opening of the spray valve is continuously increased to a large opening, the flow state in the valve is close to straight pipe flow, the pressure difference between the inlet and the outlet is reduced, the valve core assembly 4 drives the valve seat assembly 5 to rotate, the valve seat 14 rotates to continuously increase the overlapping area of the first baffle 15 and the second baffle 16, and the flow area of the medium reaching the inlet side of the disc spring 6 also continuously increases. The throttling action of the medium is significantly reduced, the pressure drop at the inlet side of the disc spring 6 is very small, and the phenomenon that the disc spring 6 is extruded out of the valve seat 14 to cause the sealing failure of the valve core assembly 4 and the valve seat assembly 5 due to the excessive throttling action of the first baffle 15 and the second baffle 16 at a large opening is avoided.

[0040] The above-described embodiments are only a preferred scheme of the present application, and are not intended to limit the present application. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application. Therefore, any technical scheme obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present application.

Claims

1. A spray valve structure capable of adjusting the force of a disc spring according to the opening degree, comprising a lower flange (1), a lower fixed bushing (3), a disc spring (6), an upper fixed bushing (7) and a valve stem (9), characterized in that, The valve body (2) is provided with a second baffle (16), the valve core assembly (4) is provided with a first bevel gear (10), and the valve seat assembly (5) is provided with a second bevel gear (13); The bottom of the valve body (2) is connected with a lower flange (1), and the inner wall of the inlet end is circumferentially provided with a plurality of second protruding baffles (16), all of which are arc strip structures capable of forming concentric circles. The valve core assembly (4) comprises coaxially arranged in sequence a first bevel gear (10), a ball core (11) and a positioning shaft (12); the first bevel gear (10) is fixedly connected with the ball core (11) and is detachably fixedly connected with the bottom of the valve rod (9) internally, and the valve rod (9) is rotatably sleeved in the upper fixed bushing (7); the ball core (11) and the positioning shaft (12) are detachably fixedly connected, and the positioning shaft (12) is rotatably sleeved in the lower fixed bushing (3) in the valve body (2); The valve seat assembly (5) comprises a second bevel gear (13), a valve seat (14) and a first baffle (15); the valve seat (14) is clamped on the inlet end of the valve body (2) and can be axially fixed, and a disc spring (6) is arranged to pre-tighten the valve seat (14) and the ball core (11) to form a linear seal in the horizontal direction; the valve seat (14) is fixedly connected at the end with the second bevel gear (13) capable of meshing and transmitting with the first bevel gear (10), and the valve seat (14) can rotate in the valve body (2); the outer wall of the front end of the valve seat (14) is circumferentially provided with a plurality of first protruding baffles (15), all of which are arc strip structures capable of forming concentric circles; the first baffles (15) and the second baffles (16) are arranged in front of and behind each other, and the two can have face coincidence and no coincidence area in the initial state, and the fluid pressure of the medium on the inlet side of the disc spring (6) can be changed by adjusting the coincidence area.

2. The spray valve structure according to claim 1, wherein the first bevel gear (10) and the second bevel gear (13) are both annular structures.

3. The spray valve structure according to claim 1, wherein the valve rod (9) is externally sleeved with a valve rod blowout prevention ring (8).

4. The spray valve structure according to claim 1, wherein the valve rod (9) can adjust the valve opening degree to 0-90° by rotating the valve core assembly (4).

5. The spray valve structure according to claim 1, wherein the first bevel gear (10) and the ball core (11), and the valve seat (14) and the second bevel gear (13) are all connected by welding.

6. The spray valve structure according to claim 1, wherein the area of the first baffle (15) is smaller than that of the second baffle (16) to ensure that there is always a medium passage between them.

7. The spray valve structure according to claim 1, wherein the number of the first baffles (15) is the same as that of the second baffles (16).

8. The spray valve structure according to claim 1, wherein the first bevel gear (10) is connected to the valve rod (9), the ball core (11) and the positioning shaft (12) through a spline fit.

9. A method of adjusting the structure of a spray valve using the disc spring force-adjustable spray valve structure according to any one of claims 1 to 8, characterized by, The specific implementation is as follows: S1: After the spray valve is opened at a small opening degree, the valve rod (9) drives the valve core assembly (4) to rotate, and the V-shaped notch area of the ball core (11) enters the flow-through area of the valve seat assembly (5); the medium enters the inside of the valve body (2) through the gap between the valve core assembly (4) and the valve seat assembly (5), at this time, the medium is subjected to throttling by the ball core (11) to generate a large pressure drop, and at this time, the medium on the inlet side needs to pass through the medium passage between the first baffle (15) and the second baffle (16) to reach the inlet side of the disc spring (6), that is, the medium will first be subjected to the throttling action of the medium passage and then reach the inlet side of the disc spring (6), which makes the fluid pressure on the inlet side of the disc spring (6) drop, reduces the pressure difference on both sides due to the throttling action of the ball core (11), and avoids the phenomenon that the disc spring (6) is extruded away from the valve body (2) due to the large pressure on the inlet side, resulting in internal leakage of the valve; S2: When the spray valve opening degree is continuously increased to a large opening degree, the flow state in the valve approaches straight pipe flow, the pressure difference between the inlet and outlet is reduced, the valve core assembly (4) drives the valve seat assembly (5) to rotate, the rotation of the valve seat (14) makes the overlapping area of the first baffle (15) and the second baffle (16) continuously increase, the flow-through area of the medium reaching the inlet side of the disc spring (6) also continuously increases, the throttling action of the medium is significantly reduced, the pressure drop on the inlet side of the disc spring (6) is very small, and the phenomenon that the disc spring (6) is extruded away from the valve seat (14) due to the too small pressure on the inlet side caused by the excessive throttling action of the first baffle (15) and the second baffle (16) at a large opening degree is avoided, which avoids the sealing failure of the valve core assembly (4) and the valve seat assembly (5).

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