Double-layer valve cover for lift valves

Abstract

This utility model relates to a double-layer valve cover for a lift-type valve, comprising a valve stem, an upper valve cover body and a lower valve cover body fixedly to the valve stem at intervals. Both the upper and lower valve cover bodies are disc-shaped, with a first sealing ring at the bottom edge of the disc and a second sealing ring on the lower surface of the upper flange. The outer diameter of the lower valve cover body is smaller than that of the upper valve cover body. The key technical features are: the first sealing ring has a duckbill-shaped cross-section with its opening side facing inward; the first sealing ring consists of an internal deformable metal skeleton and an external rubber coating; multiple positioning sleeves are evenly distributed on the bottom surface of the upper valve cover body, and a longitudinal spring is fixed within each positioning sleeve, with the lower end of the longitudinal spring abutting against the edge of the upper surface of the lower valve cover body. This utility model further solves the problem of poor sealing under long-term high-temperature corrosion, transforming a passive approach into an active one, significantly improving the reliability of the valve cover.

Description

Technical Field

[0001] This utility model relates to the technical field of valve cover structure, specifically to a double-layer valve cover for a lift valve. Background Technology

[0002] Lift-type valves are commonly used auxiliary facilities in dust removal systems and require high sealing performance to prevent pollution caused by leakage of dust-laden flue gas. Currently, to ensure the stability and reliability of the sealing structure, a double-layer valve cover structure is usually designed.

[0003] For example, CN 208719385 U discloses a double-seal lift valve, which includes a valve body with a sealing kit, a valve cover kit, a lift drive assembly connected to the valve cover kit via a guide rod, and a guide rod seat set on the axis of the valve body. The valve cover kit includes a first spring post, a first valve cover, a second spring post, and a second valve cover, which are fixedly connected from top to bottom. The sealing kit includes a first sealing kit and a second sealing kit with upper and lower layers. Both the first and second valve covers are composed of a circular valve plate and a cover plate fixed to the valve plate near the outer edge. Both the first and second sealing kits are composed of a valve seat, a spring base, and a fixed post arranged in concentric rings from the inside to the outside. Multiple pairs of helical springs are set on the top of the spring base, and a sealing ring is set on the top of the fixed post. This lift valve improves the sealing performance of the valve body by setting a double-layer valve cover kit. However, the following problems still exist during use: under long-term high-temperature corrosion, the sealing surface of the sealing ring of each valve cover will be damaged, and the sealing ring is a passive sealing structure, which is very easy to lead to poor sealing. Utility Model Content

[0004] The purpose of this invention is to provide a double-layer valve cover for lift valves that has a reasonable structure and reliable use, further solving the problem of poor sealing under long-term high-temperature corrosion, changing from a passive to an active approach, and significantly improving the reliability of the valve cover.

[0005] The technical solution of this utility model is: A double-layer valve cover for a lift valve includes a valve stem, an upper valve cover body and a lower valve cover body fixed at intervals on the valve stem. The upper and lower valve cover bodies are both disc-shaped. A first sealing ring is provided on the bottom edge of the disc, and a second sealing ring is provided on the lower surface of the upper flange of the disc. The outer diameter of the lower valve cover body is smaller than that of the upper valve cover body. The key technical features are: the cross-section of the first sealing ring is duckbill-shaped with its opening side facing inward; the first sealing ring is composed of an internal deformable metal skeleton and an external rubber coating; a plurality of positioning sleeves are evenly provided on the bottom surface of the upper valve cover body; a longitudinal spring is fixed in the positioning sleeve; and the lower end of the longitudinal spring abuts against the edge of the upper surface of the lower valve cover body.

[0006] The aforementioned double-layer valve cover for a lift valve has an annular boss embedded in the bottom surface of a disc on the upper surface of the first sealing ring. The annular boss has an annular metal skeleton concentric with it, and the annular metal skeleton has a rubber coating on its exterior. The upper surface of the first sealing ring is bonded and fixed to the bottom surface of the disc.

[0007] In the aforementioned double-layer valve cover for a lift valve, the second sealing ring is a flat gasket.

[0008] In the aforementioned double-layer valve cover for a lift valve, the bottom surface of the first sealing ring is an inclined surface for engaging with the stop portion of the valve body. The inclined surface is lower on the inside and higher on the outside, and the inner circumferential surface of the first sealing ring transitions with its upper and lower surfaces using an arc surface.

[0009] The aforementioned double-layer valve cover for a lift valve has a fixed sleeve at the center of the upper valve cover body and the lower valve cover body that cooperates with the valve stem. Multiple diagonal braces are evenly arranged between the outer circumferential surface of the fixed sleeve and the upper surface of the disc to enhance the strength of the valve.

[0010] The beneficial effects of this utility model are: Because the cross-section of the first sealing ring is duckbill-shaped, when it is compressed, when high-pressure flue gas invades, the flue gas enters the inside of the "duckbill", making the upper and lower surfaces of the first sealing ring more tightly contact the upper and lower valve cover bodies and valve bodies. Even if the surface is corroded by high temperature, it will still be in close contact with the valve cover body and valve body under the action of high-pressure flue gas. The high-pressure flue gas is used to achieve active compensation, thereby solving the problem of poor sealing under long-term high-temperature corrosion. It changes from passive to active, significantly improving the reliability of the valve cover. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 yes Figure 1 Enlarged view of section A in the middle; Figure 3 This is a schematic diagram of the structure of the first sealing ring of this utility model.

[0012] In the figure: 1. Valve stem, 2. Fixing sleeve, 3. Diagonal tie rod, 4. Upper valve cover body, 5. Valve body, 6. Positioning sleeve, 7. Longitudinal spring, 8. Second sealing ring, 9. First sealing ring, 901. Internal deformable metal skeleton, 902. External rubber coating, 903. Annular metal skeleton, 904. Annular boss, 10. Lower valve cover body. Detailed Implementation

[0013] The present invention will be described in detail with reference to the accompanying drawings.

[0014] like Figures 1-3As shown, the double-layer valve cover for a lift valve includes a valve stem 1, an upper valve cover body 4 and a lower valve cover body 10 fixed to the valve stem 1 at intervals. The upper valve cover body 4 and the lower valve cover body 10 are both disc-shaped, with a first sealing ring 9 provided at the bottom edge of the disc and a second sealing ring 8 provided on the lower surface of the upper flange of the disc. The outer diameter of the lower valve cover body 10 is smaller than the outer diameter of the upper valve cover body 4.

[0015] Wherein: the first sealing ring 9 has a duckbill-shaped cross-section with its opening side facing inward. The first sealing ring 9 is composed of an inner deformable metal skeleton 901 and an outer rubber coating 902. In this embodiment, the upper surface of the first sealing ring 9 is further provided with an annular boss 904 embedded in the bottom surface of the disc. The annular boss 904 has an annular metal skeleton 903 concentric with it. The annular metal skeleton 903 is covered with a rubber coating. The upper surface of the first sealing ring 9 is bonded and fixed to the bottom surface of the disc. The bottom surface of the first sealing ring 9 is an inclined surface for cooperating with the stop part of the valve body 5. The inclined surface is lower on the inside and higher on the outside. The inner circumferential surface of the first sealing ring 9 transitions with its upper and lower surfaces using an arc surface. The second sealing ring 8 is flat.

[0016] The bottom surface of the upper valve cover body 4 is evenly provided with multiple positioning sleeves 6, and a longitudinal spring 7 is fixed in the positioning sleeve 6. The lower end of the longitudinal spring 7 abuts against the edge of the upper surface of the lower valve cover body 10. The center of the upper valve cover body 4 and the lower valve cover body 10 is provided with a fixing sleeve 2 that cooperates with the valve stem 1. Multiple diagonal braces 3 are evenly provided between the outer circumferential surface of the fixing sleeve 2 and the upper surface of the disc to enhance the strength of use.

[0017] Working principle: In use, the upper valve cover body 4 cooperates with the upper stop of the valve body 5, and the lower valve cover body 10 cooperates with the lower stop of the valve body 5. The lower end of the longitudinal spring 7 abuts against the edge of the upper surface of the lower valve cover body 10 to enhance the sealing effect of the lower valve cover body 10.

[0018] After the first sealing ring 9 is compressed, the opening side of the deformable metal skeleton contracts slightly. When high-pressure flue gas intrudes, the flue gas enters the inside of the "duckbill", making the upper and lower surfaces of the first sealing ring 9 more tightly contact the upper and lower valve cover body and valve body. Even if the surface is corroded by high temperature, it will still be in close contact with the valve cover body and valve body under the action of high-pressure flue gas. The high-pressure flue gas is used to achieve active compensation, which greatly enhances the sealing performance.

[0019] The embodiments of this utility model have been described in detail above, but the content described is only a preferred embodiment of this utility model and should not be considered as limiting the scope of implementation of this utility model. All equivalent changes and improvements made within the scope of this utility model should still fall within the scope of this utility model.

Claims

1. A double-layer valve cover for a lift-type valve, comprising a valve stem, an upper valve cover body and a lower valve cover body fixedly and spaced apart on the valve stem, wherein the upper valve cover body and the lower valve cover body are both disc-shaped, a first sealing ring is provided on the bottom edge of the disc, and a second sealing ring is provided on the lower surface of the upper flange of the disc, wherein the outer diameter of the lower valve cover body is smaller than the outer diameter of the upper valve cover body, characterized in that: The first sealing ring has a duckbill-shaped cross-section with its opening side facing inward. The first sealing ring is composed of an internal deformable metal skeleton and an external rubber coating. Multiple positioning sleeves are evenly provided on the bottom surface of the upper valve cover body. A longitudinal spring is fixed in the positioning sleeve, and the lower end of the longitudinal spring abuts against the edge of the upper surface of the lower valve cover body.

2. The double-layer valve cover for a lift valve according to claim 1, characterized in that: The upper surface of the first sealing ring is further provided with an annular boss that is embedded in the bottom surface of the disk. The annular boss is provided with an annular metal skeleton concentric with it. The annular metal skeleton is provided with a rubber coating. The upper surface of the first sealing ring is bonded and fixed to the bottom surface of the disk.

3. The double-layer valve cover for a lift valve according to claim 1, characterized in that: The second sealing ring is flat.

4. The double-layer valve cover for a lift valve according to claim 1, characterized in that: The bottom surface of the first sealing ring is an inclined surface for cooperating with the stop part of the valve body. The inclined surface is lower on the inside and higher on the outside. The inner circumferential surface of the first sealing ring is transitioned to its upper and lower surfaces by a circular arc surface.

5. The double-layer valve cover for a lift valve according to claim 1, characterized in that: The upper valve cover body and the lower valve cover body are provided with a fixed sleeve that cooperates with the valve stem at the center. Multiple diagonal braces are evenly provided between the outer circumferential surface of the fixed sleeve and the upper surface of the disc.

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