A valve core wear-resistant structure of a steam turbine bypass valve

Abstract

The utility model discloses a kind of steam turbine bypass valve valve core wear-resistant structures, it is related to steam turbine bypass valve technical field, including valve core, the upper part of the valve core outer ring side is provided with two upper metal seal rings, the lower part of the valve core outer ring side is provided with two lower metal seal rings, the outer side of the upper metal seal ring and the lower metal seal ring is all provided with metal ceramic coating.The utility model is provided with metal ceramic coating, upper metal seal ring and lower metal seal ring, so that between valve core and guide sleeve when opening and closing, the metal ceramic coating of the outer side of upper metal seal ring and lower metal seal ring improves wear resistance, protects upper metal seal ring and lower metal seal ring, avoids being damaged by steam cavitation erosion after abrasion, and then guarantee the sealing property of valve core.

Description

Technical Field

[0001] This utility model relates to the field of turbine bypass valve technology, specifically a wear-resistant structure for the valve core of a turbine bypass valve. Background Technology

[0002] A turbine bypass valve is a mechanical device used to protect the high-pressure heater. The turbine bypass device primarily has three functions: starting, overflow, and...

[0003] 1. In cold, warm, and hot conditions, the bypass system can achieve optimal start-up and shutdown of the unit. According to the turbine operating conditions and start-up / shutdown curve requirements, it can meet both automatic and manual operation modes, and work with the boiler to establish a steam temperature that is compatible with the turbine configuration, thus shortening the unit's start-up time.

[0004] 2. When the turbine trips, the bypass system can quickly activate to reach the fully open position.

[0005] 3. When the turbine load changes, the bypass system has a regulating function, which can prevent the safety valve from activating when the operating state changes instantaneously, thus improving the operating stability of the boiler.

[0006] Under the influence of high-temperature and high-pressure steam, the valve core of the existing bypass valve is prone to wear between the valve core and the guide sleeve after a long period of opening and closing. The steam can easily cause cavitation on the seals, reducing the sealing performance of the valve core. At the same time, the outer ring of the existing valve core has a smooth surface structure, and the valve body only reduces the pressure of high-temperature and high-pressure steam through a small hole on the guide sleeve, which is generally not effective. Utility Model Content

[0007] The technical problem to be solved by this utility model is to overcome the existing defects and provide a wear-resistant structure for the valve core of a steam turbine bypass valve. By setting a metal-ceramic coating, an upper metal sealing ring and a lower metal sealing ring, the metal-ceramic coating on the outer side of the upper and lower metal sealing rings improves the wear resistance of the valve core and the guide sleeve during opening and closing, and protects the upper and lower metal sealing rings from being damaged by steam cavitation after wear, thereby ensuring the sealing performance of the valve core. This can effectively solve the problems in the background art.

[0008] To achieve the above objectives, this utility model provides the following technical solution: a wear-resistant structure for a turbine bypass valve core, comprising a valve core, wherein two upper metal sealing rings are provided on the upper part of the outer ring side of the valve core, and two lower metal sealing rings are provided on the lower part of the outer ring side of the valve core, wherein the outer surfaces of the upper metal sealing rings and the lower metal sealing rings are provided with a metal-ceramic coating, and a pressure-reducing protrusion is integrally formed on the outer ring side of the valve core.

[0009] Furthermore, a support cover is provided at the upper end of the valve core, and the support cover has screw holes circumferentially opened.

[0010] Furthermore, a connecting seat is integrally formed on the center of the upper side of the support cover, and a fastening bolt hole is opened on the side of the connecting seat.

[0011] Furthermore, both the upper metal sealing ring and the lower metal sealing ring are interference-fitted to the valve core, and the pressure-reducing protrusion has a frustum-shaped structure.

[0012] Furthermore, the support cover is connected to the valve core by bolts, and the lower end of the valve core is provided with a chamfered structure.

[0013] Furthermore, the valve core is a solid structure.

[0014] Compared with the prior art, the beneficial effects of this utility model are:

[0015] 1. This utility model, through the setting of a metal-ceramic coating, an upper metal sealing ring, and a lower metal sealing ring, improves the wear resistance of the metal-ceramic coating on the outer side of the upper and lower metal sealing rings during opening and closing of the valve core and guide sleeve, protects the upper and lower metal sealing rings, and prevents them from being damaged by steam cavitation after wear, thereby ensuring the sealing performance of the valve core.

[0016] 2. This utility model, through the valve core and pressure-reducing protrusion, allows steam passing through the small holes on the guide sleeve to collide with the pressure-reducing protrusion, causing the high-pressure steam to spread rapidly and reduce the steam pressure. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the main structure of this utility model;

[0018] Figure 2 This is a schematic diagram of the main cross-sectional structure of the lower metal sealing ring in this utility model;

[0019] Figure 3 This utility model Figure 1 Enlarged structural diagram at point A;

[0020] Figure 4 This is a schematic diagram of the structure of the valve core after it is separated from the guide sleeve in this utility model.

[0021] In the diagram: 1. Valve core; 2. Lower metal sealing ring; 3. Support cover; 4. Connecting seat; 5. Screw hole; 6. Metal-ceramic coating; 7. Pressure-reducing protrusion; 8. Upper metal sealing ring. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] Please see Figure 1-4 This embodiment provides a technical solution: a wear-resistant structure for a turbine bypass valve core, including a valve core 1, with two upper metal sealing rings 8 on the upper part of the outer ring side of the valve core 1, and two lower metal sealing rings 2 on the lower part of the outer ring side of the valve core 1. The outer surfaces of the upper metal sealing rings 8 and the lower metal sealing rings 2 are all provided with a metal-ceramic coating 6, and a pressure-reducing protrusion 7 is integrally formed on the outer ring side of the valve core 1.

[0024] like Figure 1-4 As shown, when the valve stem drives the valve core 1 to move up and down inside the guide sleeve, the upper metal sealing ring 8 and the lower metal sealing ring 2 are in close contact with the inner side of the guide sleeve, thereby sealing the valve core 2 with the inner side of the guide sleeve. The pressure reducing hole on the guide sleeve is aligned with the pressure reducing protrusion 7. High-temperature and high-pressure steam enters the valve core 1 from the outer side of the guide sleeve through the pressure reducing hole. The steam impacts the pressure reducing protrusion 7, allowing the steam to diffuse rapidly and further reduce the steam pressure. The metal ceramic coating 6 can improve the wear resistance between the upper metal sealing ring 8 and the lower metal sealing ring 2 and the guide sleeve, preventing the protective layer of the upper metal sealing ring 8 and the lower metal sealing ring 2 from being damaged by steam cavitation after wear, thereby ensuring the sealing performance of the valve core 1.

[0025] A support cover 3 is provided on the upper end of the valve core 1. The support cover 3 has screw holes 5 circumferentially opened. Connecting screws are installed in the screw holes 5, which can connect and fix the valve core 1 and the support cover 3 into a whole.

[0026] The upper side center of the support cover 3 has an integrally formed connecting seat 4. The connecting seat 4 has fastening bolt holes on its side. The connecting seat 4 can be connected to the valve stem, and the valve stem can be fixed inside the connecting seat 4 by fastening bolts.

[0027] Both the upper metal sealing ring 8 and the lower metal sealing ring 2 are interference-fitted to the valve core 1, and the pressure reducing protrusion 7 has a frustum-shaped structure.

[0028] The support cover 3 is connected to the valve core 1 by bolts. The lower end of the valve core 1 is provided with a chamfer structure, which facilitates the downward movement of the valve core 1.

[0029] Valve core 1 is a solid structure.

[0030] The working principle of the wear-resistant structure of the turbine bypass valve core provided by this utility model is as follows: Figures 1-4As shown, when the valve stem drives the valve core 1 to move up and down inside the guide sleeve, the upper metal sealing ring 8 and the lower metal sealing ring 2 are in close contact with the inner side of the guide sleeve, thereby sealing the valve core 2 with the inner side of the guide sleeve. The pressure reducing hole on the guide sleeve is aligned with the pressure reducing protrusion 7. High-temperature and high-pressure steam enters the valve core 1 from the outer side of the guide sleeve through the pressure reducing hole. The steam impacts the pressure reducing protrusion 7, allowing the steam to diffuse rapidly and further reduce the steam pressure. The metal ceramic coating 6 can improve the wear resistance between the upper metal sealing ring 8 and the lower metal sealing ring 2 and the guide sleeve, preventing the protective layer of the upper metal sealing ring 8 and the lower metal sealing ring 2 from being damaged by steam cavitation after wear, thereby ensuring the sealing performance of the valve core 1.

[0031] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the content of this utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A wear-resistant structure for a turbine bypass valve core, comprising a valve core (1), characterized in that: The valve core (1) has two upper metal sealing rings (8) on the upper part of the outer ring side and two lower metal sealing rings (2) on the lower part of the outer ring side. The outer surfaces of the upper metal sealing rings (8) and the lower metal sealing rings (2) are both provided with metal ceramic coatings (6). The valve core (1) has pressure relief protrusions (7) integrally formed on the outer ring side.

2. The wear-resistant structure of the turbine bypass valve core according to claim 1, characterized in that: The valve core (1) is provided with a support cover (3) at its upper end, and the support cover (3) is provided with screw holes (5) in the circumferential direction.

3. The wear-resistant structure of the turbine bypass valve core according to claim 2, characterized in that: The support cover (3) has a connecting seat (4) integrally formed on the center of its upper side, and the connecting seat (4) has fastening bolt holes on its side.

4. The wear-resistant structure of the turbine bypass valve core according to claim 1, characterized in that: The upper metal sealing ring (8) and the lower metal sealing ring (2) are both interference-fitted to the valve core (1), and the pressure reducing protrusion (7) is a frustum-shaped structure.

5. The wear-resistant structure of the turbine bypass valve core according to claim 2, characterized in that: The support cover (3) is connected to the valve core (1) by bolts, and the lower end of the valve core (1) is provided with a chamfer structure.

6. The wear-resistant structure of the turbine bypass valve core according to claim 1, characterized in that: The valve core (1) is a solid structure.

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