A valve trim assembly for a control valve

Abstract

The utility model relates to the technical field of governing valve, especially point to a valve gate subassembly and governing valve of governing valve, solved the sealing failure of the problem that the air intermingling of internal sealing in the prior art leads to, the control cavity is easy to freeze failure under low temperature environment, valve gate subassembly includes valve gate main part, the top of valve gate main part is equipped with recess, is equipped with sealing block in recess, the top surface of sealing block completely covers the end surface of main valve export cavity. Governing valve includes main valve body and valve gate subassembly, is equipped with main valve import cavity and main valve export cavity in main valve body, and the communication position of main valve import cavity and main valve export cavity forms valve seat, and the top surface of valve gate subassembly cooperates with valve seat sealing surface. The utility model has the beneficial effect that: because the gap edge between sealing block and valve gate main part all are located in main valve import cavity, when the medium of import end penetrates the gap, will return to import end through axial air hole, spring cavity and radial air hole in proper order, from the root, the air intermingling problem is eliminated, guarantees the reliability of internal sealing.

Description

Technical Field

[0001] This utility model relates to the field of regulating valve technology, and in particular to a valve assembly and regulating valve of a regulating valve. Background Technology

[0002] In new energy and specialty gas transportation systems, pressure regulating valves are core components for achieving precise control of medium pressure, and their operational reliability directly affects the overall system stability. For pressure regulating valves at the output front end of LNG tanks used in vehicles, they must be able to operate in a wide temperature range of -195 to +85℃, handle cryogenic media such as LNG and LN2 with inlet pressures up to 2.5 MPa and outlet pressures of 0.2-1.2 MPa, and simultaneously meet the requirements for sealing reliability and anti-icing during long-term use.

[0003] In existing technologies, the pressure-reducing valve assembly of a booster control valve is typically assembled from a sealing ring (non-metallic material) and a valve body (metallic material) using a sealing process. However, due to the differences in physical properties between metallic and non-metallic materials, the sealing process makes it difficult to achieve a seamless fit between the two. This allows low-temperature media to easily leak into the product through the tiny gaps between the sealing block and the pressure-reducing valve body, causing internal seal failure and resulting in outlet pressure fluctuations, thus affecting the stability of system operation.

[0004] For example, existing patent document CN118517559A discloses a high-precision adjustable pressure reduction ratio hydrogen pressure reducing valve and method, which achieves high-precision pressure regulation through a combination of a first-stage reverse unloading pressure reducing structure and a second-stage electromagnetic proportional pressure reducing valve, combined with PID closed-loop control. However, the valve assembly of this patent still adopts a traditional separate structure of metal valve body and non-metallic sealing ring, and the two are assembled and fixed through a sealing process.

[0005] The above structural design has inherent defects: the assembly accuracy of the sealing process depends on the control of machining tolerances, making it difficult to completely eliminate the tiny gaps between the metal valve body and the non-metallic sealing block, and the medium is prone to leakage through the gaps.

[0006] It is particularly noteworthy that the valve assembly of this patent has not been structurally optimized for media permeability or temperature adaptability. Its sealing structure can only meet the basic sealing requirements under normal operating conditions. When applied to cryogenic media such as LNG, the low temperature will exacerbate the shrinkage and deformation of the non-metallic sealing block, further increasing the sealing gap and making the problem of gas leakage more prominent. It cannot meet the sealing reliability requirements in cryogenic environments.

[0007] Furthermore, traditional control valves typically have a vent in the control chamber to balance the air pressure inside and outside the chamber when the diaphragm actuates. However, in cryogenic environments such as LNG, the temperature inside the control chamber drops to extremely low levels due to heat conduction. Moisture in the outside air condenses into water droplets upon cooling, enters the control chamber through the vent, and gradually freezes into ice. This ice then fixes the regulating spring, preventing the valve from regulating pressure and ultimately causing product failure, significantly increasing equipment maintenance costs and operational risks. Utility Model Content

[0008] This invention proposes a sealing structure for a pressure regulating valve, which solves the problems of sealing failure caused by internal seal leakage and easy freezing failure of the control cavity in low-temperature environments in the prior art.

[0009] The technical solution of this utility model is implemented as follows: A valve assembly for a control valve includes a valve body with a groove on its top. A sealing block is disposed within the groove, and the top surface of the sealing block completely covers the end face of the main valve outlet. The sealing block is an integral design, and a tapering structure is provided along the edge of the groove to fix the sealing block and achieve connection between the sealing block and the valve body. The edge of the gap between the sealing block and the valve body is entirely located within the main valve inlet, ensuring that when the inlet medium enters the gap, it will not enter the main valve outlet, thus guaranteeing the reliability of the internal seal.

[0010] The lower part of the valve body is provided with a spring cavity, and the valve body is provided with an axial vent hole, which connects the groove and the spring cavity. There is at least one axial vent hole; the axial vent hole guides the medium that seeps into the gap to the spring cavity, preventing the medium from entering the gap and pushing up the middle part of the sealing block.

[0011] The valve body is provided with radial vent holes, which connect the spring cavity and the main valve inlet cavity. There is at least one radial vent hole; the radial vent hole and the axial vent hole form a loop, so that the medium that seeps into the gap flows back to the main valve inlet cavity in sequence through the axial vent hole, the spring cavity and the radial vent hole.

[0012] The sealing block has a connecting groove at its top center. The connecting groove is adapted to the end of the valve stem and has a positioning function to ensure that the valve stem is firmly and stably pressed against the sealing block.

[0013] A regulating valve includes a main valve body and a valve assembly. The main valve body has a main valve inlet and a main valve outlet. The connection between the main valve inlet and the main valve outlet forms a valve seat. The top surface of the valve assembly cooperates with the sealing surface of the valve seat.

[0014] A control component is connected to the main valve body, and a diaphragm is provided between the main valve body and the control component. The control component cooperates with the main valve body to clamp the edge of the diaphragm.

[0015] The control assembly includes a control housing with an adjusting screw threaded onto it. An adjusting spring is located inside the control housing; the upper end of the adjusting spring engages with the adjusting screw, and the lower end engages with a diaphragm. The spring preload can be adjusted by rotating the adjusting screw, thereby setting the valve outlet pressure.

[0016] A detachable plug is attached to the control housing, and the plug corresponds to the head of the adjusting screw. This blocks the connection between outside air and the spring.

[0017] The plug has a stepped surface, and a sealing gasket is provided between the stepped surface and the surface of the control housing.

[0018] A valve stem is movably connected to the main valve body. One end of the valve stem extends into the outlet of the main valve and is tightly fitted against the valve assembly, while the other end of the valve stem is tightly fitted against the diaphragm.

[0019] The beneficial effects of this utility model are: 1. Since the edge of the gap between the sealing block and the valve body is located entirely in the inlet cavity of the main valve, when the medium at the inlet end seeps into the gap, it will flow back to the inlet end in sequence through the axial vent hole, the spring cavity and the radial vent hole, thus eliminating the problem of cross-ventilation from the source and ensuring the reliability of the internal seal.

[0020] 2. By installing a plug and sealing gasket on the control housing, the cavity inside the control housing becomes a dead space, effectively preventing cold outside air from entering the control cavity and freezing into ice, which could lead to product failure. This effectively extends the product's service life, reduces maintenance costs, and indirectly lowers the overall cost of the product.

[0021] 3. The space length inside the control chamber and the plug is significantly increased, resulting in increased temperature transfer loss and a significant decrease in temperature above the control chamber, thus improving the problem of icing and freezing failure inside the control chamber of the regulating valve. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of a pressure regulating valve according to the present invention; Figure 2 This is a schematic diagram of the valve assembly structure; Figure 3 for Figure 1 Enlarged view of point A in the middle; Figure 4This is a schematic diagram of the control cavity structure.

[0024] In the diagram: 1. Main valve body, 2. Control component, 3. Plug cap, 4. Adjusting screw, 5. Valve assembly, 6. Diaphragm, 7. Sealing gasket, 11. Main valve inlet, 12. Main valve outlet, 13. Valve stem, 21. Control housing, 22. Adjusting spring, 51. Valve body, 52. Sealing block, 511. Groove, 512. Axial vent, 513. Radial vent, 521. Connecting groove. Detailed Implementation

[0025] 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.

[0026] Example 1, as Figure 2 , Figure 3 As shown, a valve assembly for a regulating valve includes a valve body 51. A groove 511 is provided on the top of the valve body 51, and a sealing block 52 is provided within the groove 511. The top surface of the sealing block 52 completely covers the end face of the main valve outlet 12. Specifically, the sealing block 52 is an integral design, and a tapering structure is provided at the edge of the groove 511. The tapering structure fixes the sealing block 52, achieving the connection between the sealing block 52 and the valve body 51. The end face of the main valve outlet 12 is the sealing surface of the valve seat. Because the top surface of the sealing block 52 completely covers the end face of the main valve outlet 12, the edge of the gap between the sealing block 52 and the groove 511 is located at the inlet end of the main valve. When the medium at the inlet end seeps into the gap, it then seeps out from the other side of the gap and still enters the inlet end of the main valve, thus eliminating the problem of cross-contamination at its source.

[0027] Furthermore, the lower part of the valve body 51 is provided with a spring cavity, and the valve body 51 is provided with an axial vent hole 512, which connects the groove 511 and the spring cavity. The valve body 51 is provided with a radial vent hole 513, which connects the spring cavity and the main valve inlet cavity 11. Specifically, the number of axial vent holes 512 is at least one, and the number of radial vent holes 513 is at least one. In this embodiment, there are two axial vent holes 512 and two radial vent holes 513, as detailed below. Figure 3As shown in the figure, the bold line represents the medium seepage path; the axial vent 512 guides the medium that has seeped into the gap to the spring cavity, preventing the medium from pushing up the middle part of the sealing block 52 after entering the gap; the radial vent 513 and the axial vent 512 form a loop, allowing the medium that has seeped into the gap to flow back to the main valve inlet 11 through the axial vent 512, the spring cavity and the radial vent 513 in sequence.

[0028] Furthermore, a connecting groove 521 is provided at the top center of the sealing block 52. The connecting groove 521 is adapted to the end of the valve stem 13, and the connecting groove 521 has a positioning function to ensure that the valve stem 13 is firmly and stably pressed against the sealing block 52.

[0029] Example 2, based on Example 1, such as Figure 1 , Figure 4 As shown, a regulating valve includes a main valve body 1 and a valve assembly 5. The main valve body 1 has a main valve inlet 11 and a main valve outlet 12. The connection between the main valve inlet 11 and the main valve outlet 12 forms a valve seat. The top surface of the valve assembly 5 mates with the sealing surface of the valve seat. Specifically, when the valve is closed, the top surface of the valve assembly 5 is in contact with the sealing surface of the valve seat, and the medium in the main valve inlet 11 cannot pass through the valve seat into the main valve outlet 12. At this time, since the top surface of the valve assembly 5 is a single sealing block 52, the edge of the gap between the sealing block 52 and the groove 511 is located inside the main valve inlet 11. After the medium in the main valve inlet 11 leaks through the gap, it flows back into the main valve inlet 11, thus preventing cross-contamination.

[0030] Furthermore, a control component 2 is connected to the main valve body 1, and a diaphragm 6 is provided between the main valve body 1 and the control component 2. The control component 2 cooperates with the main valve body 1 to clamp the edge of the diaphragm 6. The control component 2 includes a control housing 21, on which an adjusting screw 4 is threadedly connected. An adjusting spring 22 is provided inside the control housing 21. The upper end of the adjusting spring 22 is tightly engaged with the adjusting screw 4, and the lower end of the adjusting spring 22 is tightly engaged with the diaphragm 6. The spring preload can be adjusted by rotating the adjusting screw 4, thereby setting the valve outlet pressure.

[0031] Furthermore, a detachable plug 3 is connected to the control housing 2, and the plug 3 corresponds to the head position of the adjusting screw 4. The plug 3 has a stepped surface, and a sealing gasket 7 is provided between the stepped surface and the surface of the control housing 2. The structural design of the plug 3 and the sealing gasket 7 creates a dead cavity in the control chamber during pressure adjustment, isolating the external environment from the control chamber and effectively preventing cold air from entering the control chamber and freezing into ice, which could lead to product failure.

[0032] Furthermore, a valve stem 13 is movably connected inside the main valve body 1. One end of the valve stem 13 extends into the main valve outlet cavity 12 and is tightly fitted against the valve assembly 5, while the other end of the valve stem 13 is tightly fitted against the diaphragm 6.

[0033] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A valve assembly for a regulating valve, comprising a valve body (51), characterized in that, The top of the valve body (51) is provided with a groove (511), and a sealing block (52) is provided in the groove (511). The top surface of the sealing block (52) completely covers the end face of the main valve outlet (12).

2. The valve assembly of the regulating valve according to claim 1, characterized in that, The lower part of the valve body (51) is provided with a spring cavity, and the valve body (51) is provided with an axial vent hole (512), which connects the groove (511) and the spring cavity.

3. The valve assembly of the regulating valve according to claim 2, characterized in that, The valve body (51) is provided with a radial vent hole (513), which connects the spring cavity and the main valve inlet cavity (11).

4. The valve assembly of the regulating valve according to claim 3, characterized in that, The sealing block (52) has a connecting groove (521) at the top center.

5. A regulating valve, characterized in that, The valve assembly includes a main valve body (1) and a valve assembly (5) as described in any one of claims 1 to 4. The main valve body (1) has a main valve inlet chamber (11) and a main valve outlet chamber (12). The connection between the main valve inlet chamber (11) and the main valve outlet chamber (12) forms a valve seat. The top surface of the valve assembly (5) is in contact with the sealing surface of the valve seat.

6. The regulating valve according to claim 5, characterized in that, A control component (2) is connected to the main valve body (1), and a diaphragm (6) is provided between the main valve body (1) and the control component (2).

7. The regulating valve according to claim 6, characterized in that, The control assembly (2) includes a control housing (21), on which an adjusting screw (4) is threadedly connected. An adjusting spring (22) is provided inside the control housing (21). The upper end of the adjusting spring (22) is engaged with the adjusting screw (4), and the lower end of the adjusting spring (22) is engaged with the diaphragm (6).

8. The regulating valve according to claim 7, characterized in that, A detachable plug (3) is attached to the control housing (21), and the plug (3) corresponds to the head position of the adjusting screw (4).

9. The regulating valve according to claim 8, characterized in that, The cap (3) has a stepped surface, and a sealing gasket (7) is provided between the stepped surface and the surface of the control housing (21).

10. The regulating valve according to any one of claims 5 to 9, characterized in that, A valve stem (13) is movably connected inside the main valve body (1). One end of the valve stem (13) extends into the main valve outlet cavity (12) and is tightly fitted with the valve assembly (5). The other end of the valve stem (13) is tightly fitted with the diaphragm (6).

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