Large gas pipeline valve with shaft head sealing device

Abstract

The utility model discloses a large-scale gas pipeline valve with a shaft head sealing device, which comprises a nitrogen branch pipeline, a nitrogen drainage copper pipe, a nitrogen sealing ring and a ball valve, the nitrogen sealing ring is a flat copper pipe placed in a gap between a valve transverse shaft and a shaft sleeve of a large-scale valve, the flat copper pipe is wound outside the valve transverse shaft, and the ball valve is arranged in the nitrogen branch pipeline. A plurality of air holes are formed in the side wall of the flat copper pipe, the tail end of the nitrogen drainage copper pipe is communicated with an inner cavity of the flat copper pipe, the head end of the nitrogen drainage copper pipe is connected with a nitrogen header pipe through a nitrogen branch pipeline, and the ball valve is installed on the nitrogen branch pipeline. High-pressure nitrogen is input into the gap between the transverse shaft and the shaft sleeve of the valve, and gas in the valve is isolated from the outside by the nitrogen with certain pressure, so that the gas is prevented from leaking from the shaft head of the valve, post personnel and point inspection personnel are prevented from being poisoned or suffocated due to gas leakage, and the potential hazard of gas explosion accidents is eliminated.

Description

Technical Field

[0001] The utility model relates to a large gas pipeline valve (such as a butterfly valve, a quick-cut valve, a bypass valve, etc.) with a shaft head sealing device, which can effectively prevent gas leakage and belongs to the technical field of valves. Background Art

[0002] Large gas pipeline valves are critical components of large-scale gas equipment and are central to ensuring their safety. After long-term operation, large gas pipeline valves inevitably experience gas leaks from their shaft heads. These leaks can not only cause poisoning or suffocation to personnel and inspectors, but can also cause explosions. The traditional solution involves welding a sealing box to the shaft head of the large valve. The upper end of the sealing box is connected to a vent pipe, which directs the leaked gas into the vent pipe for high-altitude release. However, this method results in gas waste, necessitating improvements. Utility Model Content

[0003] The purpose of the utility model is to provide a large gas pipeline valve with a shaft head sealing device to address the shortcomings of the existing technology, so as to prevent gas leakage from the shaft head of the large gas pipeline valve and reduce gas waste.

[0004] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0005] A large gas pipeline valve with a shaft head sealing device includes a nitrogen branch pipe, a nitrogen drainage copper tube, a nitrogen sealing ring and a ball valve. The nitrogen sealing ring is a flat copper tube placed in the gap between the valve transverse axis and the shaft sleeve of the large valve. The flat copper tube is wrapped around the outside of the valve transverse axis. A plurality of air holes are provided on the side wall of the flat copper tube. The tail end of the nitrogen drainage copper tube is connected to the inner cavity of the flat copper tube, and the head end is connected to the nitrogen main pipe through the nitrogen branch pipe. The ball valve is installed on the nitrogen branch pipe.

[0006] The large gas pipeline valve with the shaft head sealing device further comprises a packing which is installed in the gap between the valve transverse axis and the shaft sleeve and is located on the inner side of the nitrogen sealing ring.

[0007] The large gas pipeline valve with the shaft head sealing device is provided with a one-way check valve installed at the head end of the nitrogen drainage copper tube.

[0008] The above-mentioned large gas pipeline valve with a shaft head sealing device is provided with sealing boxes at both ends of the valve transverse axis of the large valve. The sealing box is fixed on the shell of the large valve. The top of the sealing box is connected to the discharge pipe through a discharge branch pipe, and a discharge ball valve is installed on the discharge branch pipe.

[0009] The utility model inputs high-pressure nitrogen into the gap between the valve horizontal axis and the shaft sleeve, and the nitrogen with a certain pressure isolates the gas inside the valve from the outside, thereby preventing the gas from leaking from the valve shaft head, preventing on-duty personnel and inspection personnel from being poisoned or suffocated due to gas leakage, and thus eliminating the hidden danger of gas explosion accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention will be further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0011] Figure 1 It is a structural diagram of the utility model;

[0012] Figure 2 This is a schematic diagram of the installation of the nitrogen sealing ring.

[0013] The numbers in the figure are as follows: 1. Nitrogen branch pipe, 2. Nitrogen drainage copper pipe, 3. Nitrogen sealing ring, 4. Ball valve, 5. One-way check valve, 6. Sealing box, 7. Discharge branch pipe, 8. Discharge ball valve, 9. Valve horizontal axis, 10. Discharge pipe, 11. Large valve, 12. Shaft sleeve; 13. Packing. DETAILED DESCRIPTION

[0014] The utility model uses nitrogen with a certain pressure (higher than the pressure of the gas leakage point) to seal the gas leaking from the valve shaft head, thereby isolating the gas from the outside world and preventing gas leakage into the surrounding area, preventing on-duty personnel and inspection personnel from being poisoned or suffocated by gas leakage, and avoiding explosion accidents caused by gas system leakage.

[0015] See Figure 1 and Figure 2 The utility model mainly includes a nitrogen branch pipe 1, a nitrogen drainage copper pipe 2, a nitrogen sealing ring 3, a ball valve 4, a one-way check valve 5, a sealing box 6, a discharge branch pipe 7, a discharge ball valve 8, a discharge pipe 10 and a packing 13.

[0016] The installation steps of this utility model are as follows:

[0017] 1. The head end of the nitrogen branch pipe 1 is connected to the nitrogen main pipe, and a quick-opening ball valve 4 is installed in the middle;

[0018] 2. A one-way check valve 5 is installed at the end of the nitrogen branch pipe 1, and the one-way check valve 5 is connected to the head end of the nitrogen drainage copper pipe 2;

[0019] Third, the end of the nitrogen drainage copper tube 2 communicates with the inner cavity of the nitrogen sealing ring 3. The nitrogen sealing ring 3 is a flat copper tube placed in the gap between the valve shaft 9 and the sleeve 12. The flat copper tube wraps around the valve shaft 9 and has multiple air holes on its sidewall. A packing 13 is also installed between the valve shaft 9 and the sleeve 12, located inside the nitrogen sealing ring 3.

[0020] Fourth, the gas leakage point of the shaft head of the valve horizontal axis 9 is welded to the sealing box 6;

[0021] 5. A relief branch pipe 7 is welded on the top of the sealing box 6 , the relief branch pipe 7 is connected to the relief pipe 10 , and a relief ball valve 8 is installed in the middle of the relief branch pipe 7 .

[0022] The working principle of this utility model is as follows:

[0023] During use of the large valve 11, its housing is filled with gas. Since the gas pressure is higher than atmospheric pressure, the gas can leak out through the gap between the valve horizontal axis 9 and the shaft sleeve 12. The present invention installs a packing 13 and a nitrogen sealing ring 3 in the gap between the valve horizontal axis 9 and the shaft sleeve 12, with the packing 13 located inside the nitrogen sealing ring 3. The nitrogen sealing ring 3 is connected to the nitrogen main pipe (nitrogen source) via a nitrogen drainage copper pipe 2, a one-way check valve 5, a ball valve 4, and a nitrogen branch pipe 1. Nitrogen with a certain pressure in the nitrogen main pipe enters the gap between the valve horizontal axis 9 and the shaft sleeve 12 through the air holes on the side wall of the nitrogen sealing ring 3, making the pressure outside the packing 13 greater than the pressure inside. In this way, the gas inside the housing of the large valve 11 cannot leak out.

[0024] The nitrogen pressure can be manually adjusted via ball valve 4. If nitrogen flow is suddenly interrupted, check valve 5 prevents the gas from flowing back into the nitrogen pipeline. Meanwhile, ball valve 8 can be manually opened to release the leaked gas. This sealing device offers excellent sealing performance, is low-cost, simple to install, and easy to operate. It meets explosion-proof requirements and solves the problem of gas leakage.

Claims

1. A large gas pipeline valve with a shaft head sealing device, characterized in that: The invention comprises a nitrogen branch pipe (1), a nitrogen drainage copper pipe (2), a nitrogen sealing ring (3) and a ball valve (4), wherein the nitrogen sealing ring (3) is a flat copper pipe placed in the gap between the valve transverse axis (9) and the shaft sleeve (12) of the large valve (11), the flat copper pipe is wound around the outside of the valve transverse axis (9), and a plurality of air holes are provided on the side wall of the flat copper pipe. The tail end of the nitrogen drainage copper pipe (2) is connected to the inner cavity of the flat copper pipe, and the head end is connected to the nitrogen main pipe through the nitrogen branch pipe (1), and the ball valve (4) is installed on the nitrogen branch pipe (1).

2. A large gas pipeline valve with a shaft head sealing device according to claim 1, characterized in that: It also includes a packing (13), which is installed in the gap between the valve transverse axis (9) and the shaft sleeve (12) and is located on the inner side of the nitrogen sealing ring (3).

3. A large gas pipeline valve with a shaft head sealing device according to claim 1 or 2, characterized in that: A one-way check valve (5) is installed at the head end of the nitrogen drainage copper tube (2).

4. A large gas pipeline valve with a shaft head sealing device according to claim 3, characterized in that: A sealing box (6) is provided at both ends of the valve transverse axis (9) of the large valve (11). The sealing box (6) is fixed to the housing of the large valve (11). The top of the sealing box (6) is connected to the discharge pipe (10) through a discharge branch pipe (7). A discharge ball valve (8) is installed on the discharge branch pipe (7).

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