Water pump pressure reducing valve for important service of nuclear power plant

Abstract

The utility model discloses a water pump pressure reducing valve for an important service of a nuclear power plant. The water pump pressure reducing valve comprises a shell, an adjusting rod, a push rod base, a valve core and a valve seat, wherein the adjusting rod is arranged on the shell and can move along the axial direction of the shell; the push rod base is connected with the adjusting rod; according to the important service water pump pressure reducing valve for the nuclear power plant, through the unique size matching design of the base body and the matching section, the situation that the flow range of a traditional single-stage pressure reducing valve is limited is changed, and the important service water pump pressure reducing valve for the nuclear power plant can adapt to the wide flow range; the problems that a shaft seal water pipeline of an important service water pump of a nuclear power plant is large in leakage change due to packing abrasion, and an existing pressure reducing valve cannot meet the flow adjusting requirement are effectively solved. The shaft seal water pressure adjusting device can accurately adapt to different working conditions and accurately adjust, it is ensured that the pressure of shaft seal water is stably reduced to the value adapting to a packing structure under the different working conditions, and good lubrication and working performance of packing seal are guaranteed.

Description

TECHNICAL FIELD

[0001] The utility model relates to a nuclear power plant valve field especially relates to a nuclear power plant important plant water pump pressure reducing valve. BACKGROUND

[0002] The shaft seal form of the nuclear power plant important plant water pump is the packing seal, and its structure is mainly composed of packing, packing chamber and gland screw. The packing is lubricated by shaft seal water, and the shaft seal water pipeline is provided with a pressure reducing valve for reducing the shaft seal water from 11bar.g to 5bar.g to adapt to the packing structure.

[0003] Due to the contact with the pump shaft, the packing will be continuously worn during use, thereby causing the shaft seal water leakage to increase. According to theoretical calculation and field practice, the packing leakage is in the range of 10-1500L / h. Since the packing leakage range is wide, the Cv value required by the pressure reducing valve on the shaft seal water pipeline is wide, about in the range of 0.0067-1.005. The existing 6mm valve core single-stage pressure reducing valve is suitable for the flow of 10-500L / h, and the existing 8mm valve core single-stage pressure reducing valve is suitable for the flow of 100-1000L / h, which cannot meet the use requirements on site. SUMMARY

[0004] The utility model provides a nuclear power plant important plant water pump pressure reducing valve.

[0005] The utility model adopts the technical scheme that a nuclear power plant important plant water pump pressure reducing valve is constructed, which comprises a shell, an adjusting rod installed on the shell and movable along the axial direction of the shell, a push rod base connected with the adjusting rod, a valve core connected with the push rod base and a valve seat fixedly installed in the shell.

[0006] The valve core comprises a base body connected with the push rod base, a sealing body connected with the base body and a connecting body connected with the sealing body.

[0007] The valve seat is provided with an action hole for fluid passing, and the action hole comprises a matching section and a sealing section connected with the matching section, the base body is correspondingly arranged with the matching section, and the sealing body is correspondingly arranged with the sealing section.

[0008] The horizontal cross-sectional area of the base body gradually decreases along the direction of the push rod base towards the valve core, and the horizontal cross-sectional area of the matching section gradually decreases along the direction of the push rod base towards the valve core.

[0009] In some embodiments, the axial cross-section of the base body is arc-shaped, and the axial cross-section of the matching section is arc-shaped.

[0010] In some embodiments, the cross section of the axial direction of the base body is in a stepped shape, and the cross section of the axial direction of the fitting section is in a stepped shape.

[0011] In some embodiments, the maximum diameter of the base body is 10mm to 11mm, and the minimum diameter of the base body is 5mm to 6mm.

[0012] In some embodiments, the maximum diameter of the fitting section is 16mm to 17mm, and the minimum diameter of the fitting section is 9mm to 10mm.

[0013] In some embodiments, the nuclear power plant important service water pump pressure reducing valve further comprises a cover body, and the cover body is connected with the shell through a fastener.

[0014] In some embodiments, the cover body is provided with a receiving groove corresponding to the connecting body.

[0015] In some embodiments, the nuclear power plant important service water pump pressure reducing valve further comprises an elastic member, and two ends of the elastic member are connected to the bottom wall of the receiving groove and the connecting body respectively.

[0016] In some embodiments, the nuclear power plant important service water pump pressure reducing valve further comprises a locking member, and the locking member is connected to the adjusting rod and used for locking the relative position of the adjusting rod and the shell.

[0017] In some embodiments, a gasket is installed between the valve seat and the shell.

[0018] The utility model discloses the following beneficial effects: the unique size cooperation design of the base body and the fitting section of the nuclear power plant important service water pump pressure reducing valve changes the condition that the flow range of traditional single-stage pressure reducing valve is limited, makes the nuclear power plant important service water pump pressure reducing valve can adapt to wide flow range, effectively solve the problem that the leakage of nuclear power plant important service water pump shaft seal water pipeline changes greatly due to packing wear, and the existing pressure reducing valve cannot satisfy the flow regulation demand. And can accurately adapt to different working conditions, accurately regulate, ensure that the pressure of shaft seal water is stably reduced to the value that adapts to packing structure under different working conditions, guarantees the good lubrication and working performance of packing seal. At the same time, since it can work stably in wide flow range, effectively avoids the additional wear or damage of packing seal caused by improper shaft seal water flow regulation, prolongs the service life of packing and other components, and then improves the stability and reliability of the whole shaft seal water system, reduces the nuclear power plant operation risk caused by shaft seal water system failure. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical scheme of the utility model, the utility model will be further described below in conjunction with the drawings and embodiments, it should be understood that the following drawings only show some embodiments of the utility model, therefore should not be regarded as the limitation to the scope, for the ordinary skilled person in the art, under the premise of not paying the creative labor, still can obtain other related drawings according to these drawings. In the drawings,

[0020] Figure 1 It is the overall structure schematic diagram of the important plant water pump pressure reducing valve of nuclear power plant in some embodiments of the utility model;

[0021] Figure 2 It is the structure schematic diagram when the important plant water pump pressure reducing valve of nuclear power plant is in the closed state in some embodiments of the utility model;

[0022] Figure 3 It is the structure schematic diagram when the important plant water pump pressure reducing valve of nuclear power plant is in the first cooperation state in some embodiments of the utility model;

[0023] Figure 4 It is the structure schematic diagram when the important plant water pump pressure reducing valve of nuclear power plant is in the second cooperation state in some embodiments of the utility model. DETAILED DESCRIPTION

[0024] In order to have more clear understanding of the technical features, object and effect of the utility model, present the specific implementation of the utility model in conjunction with the drawings. In the following description, it should be understood that the orientation or position relationship of "front", "back", "upper", "lower", "left", "right", "vertical", "horizontal", "vertical", "horizontal", "top", "bottom", "inner", "outer", "head", "tail" and the like is based on the orientation or position relationship shown in the drawings, constructs and operates in a particular orientation, only for the convenience of describing the technical scheme, and should not be understood as indicating that the indicated device or element must have a particular orientation, therefore should not be regarded as the limitation to the utility model.

[0025] It also needs to be explained that unless there is an explicit provision and limitation, the terms such as "installation", "connection", "connection", "fixation", "arrangement" and the like should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements or the interaction relationship between two elements. When an element is referred to as "on" or "below" another element, the element can be "directly" or "indirectly" above another element, or there can be one or more intervening elements. The terms "first", "second", "third" and the like are only for the convenience of describing the technical solutions, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features, so the features with "first", "second", "third" and the like can be explicitly or implicitly include one or more features. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0026] Please refer to Figures 1 to 4 The utility model discloses a kind of important plant water pump pressure reducing valves of nuclear power plant, it includes shell 1, adjusting rod 2 being installed on shell 1 and can be moved along the axial direction of shell 1, push rod base 3 connected with adjusting rod 2, valve core 4 connected with push rod base 3 and valve seat 5 fixedly installed in shell 1. Among them, valve core 4 includes the base body 41 connected with push rod base 3, the sealing body 42 connected with base body 41 and the connecting body 43 connected with sealing body 42;Valve seat 5 is provided with the action hole 51 for fluid to pass, the action hole 51 includes cooperation section 511 and sealing section 512 connected with cooperation section 511, base body 41 is correspondingly arranged with cooperation section 511, sealing body 42 is correspondingly arranged with sealing section 512;The cross-sectional area of base body 41 in horizontal direction gradually decreases along the direction of push rod base 3 towards valve core 4, the cross-sectional area of cooperation section 511 in horizontal direction gradually decreases along the direction of push rod base 3 towards valve core 4.

[0027] Specifically, the maximum diameter of the base 41 is 10mm to 11mm, the minimum diameter of the base 41 is 5mm to 6mm, the maximum diameter of the fitting section 511 is 16mm to 17mm, and the minimum diameter of the fitting section 511 is 9mm to 10mm. Understandably, the base 41 and the fitting section 511 are fitted with a certain gap therebetween, in the embodiment, when the nuclear power plant important service water pump pressure reducing valve is in the closed state, the gap between the lower part of the fitting section 511 and the base 41 is 2mm, and the gap between the upper part of the fitting section 511 and the base 41 is 3mm, that is, the maximum diameter of the fitting section 511 is preferably 16mm, and the minimum diameter of the fitting section 511 is preferably 10mm. The fitting diameter can be determined according to the required flow range and the pressure after the valve. When the base 41 is 6mm and the fitting section 511 is fitted, the flow range of 10-500L / h can be adjusted, and when the base 41 is 10mm and the fitting section 511 is fitted, the flow range of 500-1500L / h can be adjusted. The fitting size of the valve core 4 and the valve seat 5 can be calculated by the Cv value required by the corresponding flow range.

[0028] In general, when the adjusting rod 2 is rotated downward, the valve core 4 also moves downward, at this time, the nuclear power plant important service water pump pressure reducing valve is in the open valve state, and the valve opening degree can gradually transition from the fitting of the 6mm base 41 and the fitting section 511 to the fitting of the 10mm base 41 and the fitting section 511. More specifically, as shown in FIG. 1, when the nuclear power plant important service water pump pressure reducing valve is in the closed state of the valve, the sealing body 42 is sealed and fitted on the connecting body 43, the action hole 51 is blocked, and the fluid cannot flow through the action hole 51. As shown in FIG. 2, when the nuclear power plant important service water pump pressure reducing valve is in the fitting state of the 6mm base 41 and the fitting section 511, the sealing body 42 is no longer fitted on the connecting body 43, and the flow range of 10-500L / h can be adjusted. As shown in FIG. 3, when the nuclear power plant important service water pump pressure reducing valve is in the fitting state of the 10mm base 41 and the fitting section 511, the flow range of 500-1500L / h can be adjusted. Figure 2 Figure 3 Figure 4

[0029] Understandably, the beneficial effects of the nuclear power plant important service water pump pressure reducing valve are:

[0030] ​​​1. Widening the flow regulation range: By designing the horizontal cross-sectional area of the base body 41 to gradually decrease in the direction of the push rod towards the valve core 4, and the horizontal cross-sectional area of the matching section 511 to gradually decrease in the direction of the push rod towards the valve core 4, and through the unique size matching design of the base body 41 and the matching section 511, the condition of the limited flow range of the traditional single-stage pressure reducing valve is changed, making the important plant water pump pressure reducing valve of the nuclear power plant adapt to a wide flow range of 10-1500L / h, effectively solving the problem that the existing pressure reducing valve cannot meet the flow regulation demand due to the large leakage variation of the shaft seal water pipeline of the nuclear power plant important plant water pump caused by packing wear;

[0031] 2. Precise adaptation to different working conditions: For different flow intervals, 6mm base body 41 can be used to regulate the 10-500L / h flow range, and 10mm base body 41 can be used to regulate the 500-1500L / h flow range. This targeted design can accurately regulate according to actual flow demand, ensuring that the shaft seal water pressure is stably reduced to 5bar.g to adapt to the packing structure under different working conditions, ensuring good lubrication and working performance of the packing seal;

[0032] 3. Improve system stability and reliability: Since it can work stably in a wide flow range, it effectively avoids additional wear or damage to the packing seal caused by improper shaft seal water flow regulation, prolongs the service life of the packing and other components, and thus improves the stability and reliability of the entire shaft seal water system, reducing the risk of nuclear power plant operation caused by shaft seal water system failure;

[0033] 4. Enhance the versatility of the pressure reducing valve: The design of the multi-stage valve core 4 and valve seat 5 size matching, compared to the single size valve core 4 pressure reducing valve, does not need to replace different specifications of pressure reducing valve for different flow ranges, greatly enhancing the versatility of the pressure reducing valve under different working conditions, reducing equipment procurement costs and maintenance management difficulty;

[0034] 5. Flexible adjustment mode: The pressure reducing valve of the utility model is not necessarily continuously adjusted, and can be designed as two-stage or multi-stage adjustment according to actual demand, and different flow ranges are switched through the size matching of the valve core 4 and the valve seat 5. This flexible adjustment mode can better adapt to complex and variable field conditions, providing more choices and convenience for practical application.

[0035] In some embodiments, the axial cross-section of the base body 41 is arc-shaped, the axial cross-section of the matching section 511 is arc-shaped, or the axial cross-section of the base body 41 is ladder-shaped, and the axial cross-section of the matching section 511 is ladder-shaped. Only the multi-stage adjustment effect of the valve core 4 needs to be met. In this embodiment, the axial cross-section of the base body 41 is preferably arc-shaped, and the axial cross-section of the matching section 511 is preferably arc-shaped.

[0036] The nuclear power plant important service water pump pressure reducing valve further comprises a cover body 6 connected with the shell 1 through a fastener, which can be a bolt. The cover body 6 is provided with a containing groove 61 corresponding to the connecting body 43. The nuclear power plant important service water pump pressure reducing valve further comprises an elastic member 7, both ends of which are connected to the bottom wall of the containing groove 61 and the connecting body 43, respectively. The elastic member 7 can be a pre-tightening spring, and when the nuclear power plant important service water pump pressure reducing valve is in a closed state, the elastic force provided by the elastic member 7 can compress the sealing body 42.

[0037] The nuclear power plant important service water pump pressure reducing valve further comprises a locking member 8 connected to the adjusting rod 2 and used for locking the relative position of the adjusting rod 2 and the shell 1. The locking member 8 can be a locking nut, and when the adjusting rod 2 is adjusted to a proper position, the relative position of the adjusting rod 2 and the shell 1 can be locked through the locking member 8.

[0038] In addition, a gasket 9 is installed between the valve seat 5 and the shell 1. The gasket 9 can be a sealing gasket, which can play a sealing role, effectively prevent fluid leakage at the connection, and ensure the sealing property of the system.

[0039] It can be understood that the above embodiment only expresses the preferred embodiment of the present application, which is described in detail, but cannot be understood as a limitation on the scope of the present application. It should be pointed out that for ordinary skilled in the art, the above technical features can be freely combined without departing from the concept of the present application, and some modifications and improvements can be made, which all belong to the protection scope of the present application. Therefore, any equivalent transformation and modification within the scope of the claims of the present application should belong to the scope of the claims of the present application.

Claims

1. A relief valve for an important service water pump of a nuclear power plant, characterized by, The nuclear power plant important service water pump pressure reducing valve comprises a shell (1), an adjusting rod (2) installed on the shell (1) and movable along the axial direction of the shell (1), a push rod base (3) connected with the adjusting rod (2), a valve core (4) connected with the push rod base (3), and a valve seat (5) fixedly installed in the shell (1); The valve core (4) comprises a base body (41) connected with the push rod base (3), a sealing body (42) connected with the base body (41), and a connecting body (43) connected with the sealing body (42); The valve seat (5) is provided with an action hole (51) for passing fluid, the action hole (51) comprises a matching section (511) and a sealing section (512) connected with the matching section (511), the base body (41) is correspondingly arranged with the matching section (511), and the sealing body (42) is correspondingly arranged with the sealing section (512); The horizontal cross-sectional area of the base body (41) gradually decreases along the direction of the push rod base (3) towards the valve core (4), and the horizontal cross-sectional area of the matching section (511) gradually decreases along the direction of the push rod base (3) towards the valve core (4).

2. The nuclear power plant important service water pump relief valve according to claim 1, characterized in that, The axial cross-section of the base body (41) is arc-shaped, and the axial cross-section of the matching section (511) is arc-shaped.

3. The nuclear power plant important service water pump relief valve of claim 1, wherein, The axial cross-section of the base body (41) is in a stepped shape, and the axial cross-section of the matching section (511) is in a stepped shape.

4. The nuclear power plant important service water pump relief valve of claim 1, wherein, The maximum diameter of the base body (41) is 10mm to 11mm, and the minimum diameter of the base body (41) is 5mm to 6mm.

5. The nuclear power plant important service water pump relief valve of claim 1, wherein, The maximum diameter of the matching section (511) is 16mm to 17mm, and the minimum diameter of the matching section (511) is 9mm to 10mm.

6. The nuclear power plant important service water pump relief valve of claim 1, wherein, The nuclear power plant important service water pump pressure reducing valve further comprises a cover body (6), and the cover body (6) is connected with the shell (1) through a fastener.

7. The nuclear power plant important service water pump relief valve of claim 6, wherein, The cover body (6) is provided with an accommodating groove (61) corresponding to the connecting body (43).

8. The nuclear power plant important service water pump relief valve of claim 7, wherein, The nuclear power plant important service water pump pressure reducing valve further comprises an elastic member (7), and two ends of the elastic member (7) are connected to the bottom wall of the accommodating groove (61) and the connecting body (43) respectively.

9. The nuclear power plant important service water pump relief valve of claim 1, wherein, The nuclear power plant important service water pump pressure reducing valve further comprises a locking member (8) connected with the adjusting rod (2) and used for locking the relative position of the adjusting rod (2) and the shell (1).

10. The nuclear power plant essential service water pump relief valve of claim 1, wherein, A gasket (9) is installed between the valve seat (5) and the shell (1).

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