High-sealing high-temperature-resistant gate valve for power station

Abstract

The utility model relates to the technical field of gate valves, and discloses a high-sealing high-temperature-resistant gate valve for a power station, which comprises a valve body, a water inlet is arranged at the left end of the valve body, a water outlet is arranged at the right end of the valve body, a valve cover is arranged at the top of the valve body, and flanges connected with a pipeline are arranged at the water inlet end and the water outlet end of the valve body. A filler is arranged in the valve cover, a high-temperature-resistant lining layer is arranged on the inner side wall of the valve body, a high-temperature-resistant coating layer is sprayed on the outer surface of the high-temperature-resistant lining layer, a valve rod is arranged at the axis position of the filler, and the lower end of the valve rod is connected with a valve element. A groove capable of being sealed with the valve element is formed in the middle of the high-temperature-resistant lining layer, and a high-temperature-resistant sealing strip is arranged in the groove. According to the high-temperature-resistant gate valve, the high-temperature-resistant lining layer and the high-temperature-resistant coating layer are arranged and are matched with each other, so that the high-temperature-resistant performance of the gate valve can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of gate valves, in particular to a high-sealing and high-temperature resistant gate valve used in power stations. Background Art

[0002] The gate valve is a gate plate of an opening and closing part. The movement direction of the gate plate is perpendicular to the direction of the fluid. The gate valve can only be fully opened and fully closed, and cannot be adjusted or throttled. The gate valve is sealed by the contact between the valve seat and the gate plate. Usually, the sealing surface will be welded with metal materials to increase wear resistance, such as 1Cr13, STL6, stainless steel, etc. The gate plate has a rigid gate plate and an elastic gate plate. According to the different gate plates, the gate valve is divided into a rigid gate valve and an elastic gate valve.

[0003] A hydropower station is composed of hydraulic systems, mechanical systems, and power generation devices. It is a water conservancy hub project that realizes the conversion of water energy into electrical energy. The sustainability of power generation requires the uninterrupted use of water energy in hydropower stations. Through the construction of the hydropower station reservoir system, the distribution of water resources in time and space is artificially adjusted and changed to achieve sustainable use of water resources. In order to effectively convert the water energy in the reservoir into electrical energy, the hydropower station needs to be realized through a hydro-mechanical system, which is mainly composed of a pressure water diversion pipe, a turbine, a generator, and a tailwater pipe. The gate valve is one of the commonly used important components of a hydropower station.

[0004] The existing gate valves used in power stations have poor high temperature resistance during use, and the sealing effect needs to be improved. Therefore, there is an urgent need for a high-sealing and high-temperature resistant gate valve for power stations to solve the above technical problems. Utility Model Content

[0005] The purpose of the utility model is to provide a high-sealing and high-temperature resistant gate valve for power stations, so as to solve the problems in the above-mentioned background technology that the existing gate valves for power stations have poor high-temperature resistance when in use and the sealing effect needs to be improved.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A high-sealing and high-temperature resistant gate valve for power stations comprises a valve body, a water inlet is provided at the left end of the valve body, a water outlet is provided at the right end of the valve body, a valve cover is provided at the top of the valve body, the water inlet and the water outlet ends of the valve body are both provided with flanges connected to the pipeline, a packing is provided inside the valve cover, a high-temperature resistant lining is provided on the inner side wall of the valve body, a high-temperature resistant coating layer is sprayed on the outer surface of the high-temperature resistant lining, a valve stem is provided at the axis of the packing, a valve core is connected to the lower end of the valve stem, a groove that can form a seal with the valve core is provided in the middle part of the high-temperature resistant lining, a high-temperature resistant sealing strip is provided in the groove, the lower end of the valve core passes through the inner cavity of the valve body and extends to the high-temperature resistant sealing strip in the bottom groove, which conflicts with the high-temperature resistant sealing strip, and the top of the valve stem passes through the top of the valve cover and is connected to the handwheel.

[0008] As a preferred technical solution of the present utility model, the material of the high temperature resistant lining layer is high temperature alloy steel.

[0009] As a preferred technical solution of the present utility model, the cross-sectional shape of the high temperature resistant sealing strip is a concave structure.

[0010] As a preferred technical solution of the present utility model, the material of the high temperature resistant sealing strip is a silicone foam sealing strip.

[0011] As a preferred technical solution of the present utility model, the connection between the valve stem and the valve core is a movable connection.

[0012] As a preferred technical solution of the utility model, a pressure self-sealing structure is adopted between the valve cover and the valve body, and the sealing ring is made of soft steel with a 30° cone angle design.

[0013] As an optimal technical solution of the present utility model, the inner seal in the valve cavity of the valve body adopts a bidirectional pressure-bearing seal design, the inner aperture of the valve seat formed by the high-temperature resistant lining layer is smaller than the inner diameter of the connecting pipe, and the inner surface of the valve cavity of the valve body and the surface of the valve core are sprayed with a high-temperature resistant coating.

[0014] Compared with the prior art, the utility model has the following beneficial effects:

[0015] The utility model provides a high temperature resistant lining layer and a high temperature resistant coating layer and utilizes the cooperation between them, thereby improving the high temperature resistance performance of the gate valve.

[0016] The inner seal in the valve cavity of the utility model adopts a two-way pressure-bearing seal design. The inner aperture of the valve seat formed by the high-temperature resistant lining layer is smaller than the inner diameter of the connecting pipe. Under the action of the Venturi effect, a flushing force will be formed on the precipitated impurities in the gate groove to take away the impurities, ensuring that the gate groove is clean and smooth.

[0017] The utility model adopts an extended valve stem design to prevent the valve stem sealing packing from being subjected to high temperature for a long time, which may cause packing erosion and reduce the sealing effect. The valve stem surface is precisely ground and hardened to resist scratches and corrosion, effectively reducing the opening and closing torque and making operation easier.

[0018] The outer sealing surface between the valve cover and the valve stem of the utility model adopts a special corrosion-inhibiting packing structure design, which is temperature and pressure resistant, corrosion-free, and automatically lubricated, reducing opening and closing friction, avoiding corrosion on the valve stem surface, and thus eliminating leakage. A pressure self-sealing structure is adopted between the valve cover and the valve body, and the sealing ring is made of soft steel with a 30° cone angle design, which is conducive to deformation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0020] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0021] Figure 2 It is a schematic cross-sectional view of the overall structure of the utility model;

[0022] Figure 3 For this utility model Figure 2 Schematic diagram of the enlarged structure at point A in the middle.

[0023] In the figure: 1. valve body; 2. valve cover; 3. valve stem; 4. hand wheel; 5. water outlet; 6. water inlet; 7. flange; 9. high temperature resistant lining layer; 10. high temperature resistant coating layer; 11. high temperature resistant sealing strip; 12. valve core; 13. packing. DETAILED DESCRIPTION

[0024] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are only used to explain the relevant utility model, rather than to limit the utility model. It should also be noted that, for ease of description, only the parts related to the utility model are shown in the accompanying drawings. The different types of section lines in the drawings in the embodiments of the utility model are not marked according to the national standard, nor are there any requirements for the materials of the components, but are used to distinguish the cross-sectional views of the components in the drawings.

[0025] See also Figure 1-3A high-sealing and high-temperature resistant gate valve for power stations comprises a valve body 1, a water inlet 6 is arranged at the left end of the valve body 1, a water outlet 5 is arranged at the right end of the valve body 1, a valve cover 2 is arranged at the top of the valve body 1, and flanges 7 connected to pipelines are arranged at the 6 water inlets and 5 water outlets of the valve body 1. A packing 13 is arranged inside the valve cover 2, a high-temperature resistant lining layer 9 is arranged on the inner side wall of the valve body 1, and a high-temperature resistant coating layer 10 is sprayed on the outer surface of the high-temperature resistant lining layer 9. A valve stem 3 is arranged at the axis of the packing 13, a valve core 12 is connected to the lower end of the valve stem 3, a groove that can form a seal with the valve core 12 is arranged in the middle part of the high-temperature resistant lining layer 9, a high-temperature resistant sealing strip 11 is arranged in the groove, and the lower end of the valve core 12 passes through the inner cavity of the valve body 1 and extends to the high-temperature resistant sealing strip 11 in the bottom groove to conflict with the high-temperature resistant sealing strip 11, and the top of the valve stem 3 passes through the top of the valve cover 2 and is connected to the hand wheel 4.

[0026] The material of the high temperature resistant lining layer 9 is high temperature alloy steel.

[0027] The cross-sectional shape of the high temperature resistant sealing strip 11 is a concave structure.

[0028] The material of the high temperature resistant sealing strip 11 is a silicone foam sealing strip.

[0029] The connection between the valve stem 3 and the valve core 12 is a movable connection.

[0030] Among them, a pressure self-sealing structure is adopted between the valve cover 2 and the valve body 1. The sealing ring is made of soft steel and has a 30° cone angle design, which is conducive to deformation. When the bolt is lifted or under the action of the medium pressure, the valve cover 2 moves, and the sealing ring is squeezed between the valve body 1 and the valve cover 2, causing deformation to prevent the medium from leaking out. The higher the medium pressure, the greater the sealing force. This sealing structure is safe and reliable, can effectively prevent medium leakage, is temperature and pressure resistant, corrosion-free, and automatically lubricates, reduces opening and closing friction, avoids corrosion on the surface of the valve stem 3, and thus avoids leakage; (When the graphite braided packing comes into contact with water, steam and other media, the electrochemical action of chloride ions and graphite in the packing often causes pitting corrosion on the surface of the valve stem. For valves with strict requirements, graphite packing that has been treated with corrosion inhibition should be used).

[0031] Among them, the inner seal in the valve cavity of the valve body 1 adopts a two-way pressure-bearing seal design. The inner aperture of the valve seat formed by the high-temperature resistant lining layer is smaller than the inner diameter of the connecting pipe. Under the action of the Venturi effect, it will form a flushing force on the impurities precipitated in the gate groove and take away the impurities, ensuring that the gate groove is clean and smooth, and the inner surface of the valve cavity and the surface of the valve core 12 are sprayed with a high-temperature resistant coating.

[0032] Among them, in order to prevent the gate deformation, valve stem dislocation and sealing surface bite caused by the influence of liquid pressure and temperature, a deep T-shaped sliding seat, spring and other structures are provided at the connection between the gate and the valve stem, so as to ensure the normal operation of the valve under any working conditions. At the same time, since there is a gap between the valve stem and the gate, when the gate is subjected to the impact force of the medium, the lateral impact force will not be transmitted to the valve stem, thereby ensuring that the valve stem has a better stress state.

[0033] When the temperature rises, the opening and closing parts will expand, which may cause the sealing surface distortion introduced by the uneven deformation of the opening and closing parts, causing the sealing surface to be damaged and not conducive to sealing. In order to compensate for the thermal deformation of the valve stem and eliminate the excessive extrusion stress between the gate and the valve seat sealing surface, three disc springs are added to the bracket head. The disc springs are grouped in threes. The positions of the disc spring feet are designed according to the force transmission method of the bearing, pressure cover and valve stem nut in the bracket head. The disc spring has small deformation and can withstand a large load. At the same time, the spring sleeved on the valve stem at the connection between the gate and the valve stem also has the function of protecting and assisting. Before the valve stem drives the gate down along the gate groove and approaches the fully closed state, the spring will generate a reverse thrust to push the gate to fully close. The spring buffering protection can better extend the service life of the components inside the valve.

[0034] The working principle and use process of the utility model: first, when in use, the valve stem 3 is driven to rotate by manually turning the hand wheel 4, so that the valve core 12 on the valve stem 3 moves upward, thereby opening the gate valve, and the high temperature resistant lining layer 9 made of high temperature alloy steel and the high temperature resistant coating layer 10 made of silicone foam sealing strip are arranged on the inner wall of the valve body 1, and the high temperature resistant lining layer 9 and the high temperature resistant coating layer 10 can improve the high temperature resistance of the gate valve;

[0035] By providing a high temperature resistant sealing strip 11, the sealing effect of the gate valve can be improved by utilizing the high temperature resistant sealing strip 11. The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

[0036] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the utility model involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the concept of the utility model. For example, the above features are replaced with the technical features with similar functions disclosed in the present application (but not limited to) by each other to form a technical solution.

Claims

1. A high-sealing, high-temperature resistant gate valve for a power station, comprising a valve body (1), characterized in that: The left end of the valve body (1) is provided with a water inlet (6), the right end of the valve body (1) is provided with a water outlet (5), the top of the valve body (1) is provided with a valve cover (2), the water inlet (6) and the water outlet (5) of the valve body (1) are both provided with flanges (7) connected to the pipeline, the inside of the valve cover (2) is provided with a packing (13), the inner side wall of the valve body (1) is provided with a high temperature resistant lining layer (9), the outer surface of the high temperature resistant lining layer (9) is sprayed with a high temperature resistant coating layer (10), the packing A valve stem (3) is arranged at the axis of the valve body (13), the lower end of the valve stem (3) is connected to the valve core (12), the middle part of the high temperature resistant lining layer (9) is provided with a groove which can form a seal with the valve core (12), a high temperature resistant sealing strip (11) is arranged in the groove, the lower end of the valve core (12) passes through the inner cavity of the valve body (1) and extends to the high temperature resistant sealing strip (11) in the bottom groove to collide with the high temperature resistant sealing strip (11), and the top of the valve stem (3) passes through the top of the valve cover (2) and is connected to the hand wheel (4).

2. A high-sealing and high-temperature resistant gate valve for a power station according to claim 1, characterized in that: The material of the high temperature resistant lining layer (9) is high temperature alloy steel.

3. The high-sealing and high-temperature resistant gate valve for power stations according to claim 1, characterized in that: The cross-sectional shape of the high temperature resistant sealing strip (11) is a concave structure.

4. A high-sealing and high-temperature resistant gate valve for a power station according to claim 1, characterized in that: The material of the high temperature resistant sealing strip (11) is a silicone foam sealing strip.

5. The high-sealing and high-temperature resistant gate valve for power stations according to claim 1, characterized in that: The connection between the valve stem (3) and the valve core (12) is a movable connection.

6. A high-sealing and high-temperature resistant gate valve for a power station according to claim 1, characterized in that: A pressure self-sealing structure is adopted between the valve cover (2) and the valve body (1); the sealing ring is made of soft steel and has a 30° cone angle design.

7. The high-sealing and high-temperature resistant gate valve for power stations according to claim 1, characterized in that: The inner seal in the valve cavity of the valve body (1) adopts a bidirectional pressure-bearing seal design, the inner aperture of the valve seat formed by the high-temperature resistant lining layer (9) is smaller than the inner diameter of the connecting pipe, and the inner surface of the valve cavity of the valve body (1) and the surface of the valve core (12) are sprayed with a high-temperature resistant coating.

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