Brass gate valve with long service life

Abstract

The utility model discloses a brass gate valve with a long service cycle, which comprises a valve body (1), a gate plate (2), a valve rod (3), a valve cover (4), a pressing cap (5) and a hand wheel (6), a cavity (7) is formed between the valve cover (4) and the valve body (1), the bottom of the valve rod (3) is closed, and an assembly capable of changing the volume of the cavity (7) is arranged on the valve body (1). The assembly comprises a shell (8), the inner side end of the shell (8) is in threaded connection with the valve body (1), an air hole (9) is formed in the outer side end of the shell (8), the shell (8) is communicated with the cavity (7), and a piston (10) is arranged in the shell (8). The piston (10) comprises at least two sealing rings (11) arranged between the piston (10) and the shell (8); a weight reduction blind hole (12) is formed in the outer side end of the piston (10). The utility model has the advantage of long service life.

Description

Technical Field

[0001] The utility model belongs to the field of brass gate valves, in particular to a brass gate valve with a long service life. Background Art

[0002] Brass gate valves (gate valves for short) are widely used in water supply systems. The structure of the gate valve is as follows: Figure 3 As shown, it includes a T-shaped valve body, gate, valve stem, valve cover, O-ring, pressure cap, hand wheel and sealing gasket. The gate is located in the middle of the valve body. The upper end of the gate passes through the valve body to cut off the flow channel in the valve body. The valve stem is screwed with the gate and passes through the valve cover and pressure cap in sequence. The O-ring is located between the valve stem and the valve cover. The pressure cap is screwed with the valve cover, and the valve cover is screwed with the valve body. The sealing gasket is located between the valve cover and the valve body, and a cavity is formed between the valve cover and the valve body. The handwheel drives the valve stem to rotate, and the valve cover drives the gate to rise and fall to realize the on and off of water flow in the valve body. During the process of the gate plate rising and falling, the volume of the cavity will change, and the medium inside the cavity needs an inlet and outlet channel. The current method is to set a through hole coaxial with the valve stem at the bottom of the gate plate. When the volume of the cavity changes, the medium inside the cavity is connected to the valve body flow channel through the gap between the valve stem and the gate plate and the through hole. That is, in the existing gate valve, the cavity and the flow channel are always connected. When the O-ring is aged and worn, the water in the flow channel will seep out, resulting in a shorter service life of the gate valve. Utility Model Content

[0003] The purpose of the utility model is to provide a brass gate valve with a long service life. The utility model has the advantage of a long service life.

[0004] The technical solution of the utility model is: a brass gate valve with a long service life, comprising a valve body, a gate, a valve stem, a valve cover, a capping hand wheel, an O-ring and a sealing gasket, a cavity is formed between the valve cover and the valve body, the bottom of the valve stem is closed, and a component that can change the volume of the cavity is provided on the valve body; the component comprises a shell, the inner end of the shell is screwed to the valve body, the outer end of the shell is provided with an air hole, the shell is connected to the cavity, and a piston is provided in the shell.

[0005] In the aforementioned brass gate valve with a long service life, the piston includes at least two sealing rings arranged between the piston and the housing.

[0006] In the aforementioned brass gate valve with a long service life, a weight-reducing blind hole is provided at the outer end of the piston.

[0007] In the aforementioned brass gate valve with a long service life, a loose sealing sleeve is provided in the cavity, the upper end of the sealing sleeve is fixed to the valve stem, the lower end of the sealing sleeve is fixed to the inner wall of the cavity, and the lower end of the sealing sleeve is located at the lower side of the assembly.

[0008] In the aforementioned brass gate valve with a long service life, a first annular groove is provided on the valve stem, an elastic first metal ring is provided in the first annular groove, the first metal ring presses the upper end of the sealing sleeve onto the valve stem, a second annular groove is provided on the inner wall of the cavity, an elastic second metal ring is provided in the second annular groove, the second metal ring tightens the lower end of the sealing sleeve onto the inner wall of the cavity.

[0009] Compared with the prior art, the utility model is based on the existing gate valve, and a component that can change the volume of the cavity is set on the valve body, and the lower end of the valve stem is sealed to prevent water in the valve body flow channel from entering the cavity, blocking the path of water to the O-ring, and preventing the gate valve from leaking due to aging and wear of the O-ring, thereby improving the service life of the gate valve. Since the O-ring does not contact water, lubricating oil can be applied to the O-ring, and the O-ring is not easy to age and wear. Even if the contact surface between the gate plate and the valve body is worn, causing water to enter the cavity, the water will still not seep out, which also improves the service life of the gate valve. Therefore, the utility model has the advantage of a long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a structural schematic diagram of Example 1.

[0011] Figure 2 It is a structural schematic diagram of Example 2.

[0012] Figure 3 It is a structural schematic diagram of an existing gate valve.

[0013] The marks in the accompanying drawings are: 1-valve body, 2-gate, 3-valve stem, 4-valve cover, 5-pressure cap, 6-handwheel, 7-cavity, 8-shell, 9-air hole, 10-piston, 11-sealing ring, 12-weight reduction blind hole, 13-sealing sleeve, 14-first metal ring, 15-second metal ring, 16-O-ring, 17-sealing gasket, 18-flow channel, 19-sealing gasket. DETAILED DESCRIPTION

[0014] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but they are not intended to limit the present invention.

[0015] Example 1. A brass gate valve with a long service life is improved on the basis of the existing gate valve, such as Figure 1As shown, it includes a valve body 1, a gate plate 2, a valve stem 3, a valve cover 4, a pressure cap 5 and a handwheel 6. The valve body 1 is T-shaped, and a horizontal flow channel is provided inside the valve body 1. The gate plate 2 is a flat plate located in the middle of the valve body 1. The lower end of the valve stem 3 is screwed to the top of the gate plate 2, the valve cover 4 is screwed to the upper end of the valve body 1, and the pressure cap 5 is screwed to the upper end of the valve cover 4. The upper end of the valve stem 3 passes through the valve cover 4 and the pressure cap 5 in sequence. A cavity 7 surrounding the valve stem 3 is formed between the valve cover 4, the valve body 1 and the gate plate 2. Two O-rings 16 are provided between the valve stem 3 and the valve cover 4, and a sealing gasket 17 is provided between the valve cover 4 and the valve body 1. The features are as follows,

[0016] The bottom of the valve stem 3 is closed, and a component that can change the volume of the cavity 7 is provided on the valve body 1; the component includes a shell 8, the inner end of the shell 8 is screwed to the valve body 1, a sealing gasket 19 is provided between the shell 8 and the valve body 1, an air hole 9 is provided at the outer end of the shell 8, the shell 8 is connected to the cavity 7, and a piston 10 is provided in the shell 8.

[0017] The piston 10 includes at least two sealing rings 11 disposed between the piston 10 and the housing 8 .

[0018] The outer end of the piston 10 is provided with a weight-reducing blind hole 12 .

[0019] Working principle: Since the bottom of the valve stem 3 is closed, the cavity 7 and the flow channel 18 of the valve body 1 are always inaccessible, and water will not enter the cavity 7 and will not seep out. The valve body 1, the valve stem 3 and the gate 2 are all made of brass, and there is no risk of aging. The gate 2 and the valve body 1 can maintain a very long-term seal, so that the gate can be used for a long time without water seepage. When the gate 2 is raised or lowered, the air pressure in the cavity 7 changes, pushing the piston 10 to move axially, so that the volume of the cavity 7 changes automatically, and the pressure inside and outside the cavity 7 is balanced, which facilitates the smooth twisting of the hand wheel 6.

[0020] Compared with the existing gate valve, Example 1 adds a component that can change the volume of the cavity 7 on the basis of the existing gate valve, and seals the lower end of the valve stem 3.

[0021] As a further optimization, the sealing ring 11 and the O-ring 16 are both moving parts, and lubricating oil can be applied on them to reduce wear. In the existing gate valve, water will enter the cavity 7 and wash away the lubricating oil, and lubricating oil is generally not applied, which is also an important reason why the existing gate valve O-ring 16 is easy to wear.

[0022] In Example 1, there are two sealing protections. The first one is between the gate plate 2 and the valve body 1. When the contact surface between the gate plate 2 and the valve body 1 is worn, the first sealing protection fails. At this time, the sealing ring 11, the O-ring 16, the sealing gasket 17 and the sealing gasket 19 work together to form the second sealing protection. If any one of the sealing protections is effective, the gate valve will not leak and can still be used.

[0023] Embodiment 2. Based on Embodiment 1, a loose sealing sleeve 13 is provided in the cavity 7, and the sealing sleeve 13 can be twisted multiple times. A first annular groove is provided on the valve stem 3, and an elastic first metal ring 14 is provided in the first annular groove. The first metal ring 14 presses the upper end of the sealing sleeve 13 onto the valve stem 3. A second annular groove is provided on the inner wall of the cavity 7, and an elastic second metal ring 15 is provided in the second annular groove. The second metal ring 15 tightens the lower end of the sealing sleeve 13 onto the inner wall of the cavity 7.

[0024] Compared with the first embodiment, the second embodiment provides an additional sealing protection. When the contact surface between the gate plate 2 and the valve body 1 is worn and the water in the flow channel 18 enters the cavity 7, the water is prevented from contacting the sealing ring 11 and the O-ring 16, and the lubrication on the sealing ring 11 and the O-ring 16 is prevented from being washed away. Since the second embodiment has three sealing protections, if any one of the sealing protections is effective, the gate valve will not leak and can still be used. The service life of the second embodiment is longer, but the production cost is also increased accordingly.

[0025] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", etc., indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

Claims

1. A brass gate valve with a long service life, comprising a valve body (1), a gate plate (2), a valve stem (3), a valve cover (4), a pressure cap (5), a hand wheel (6), an O-ring (16) and a sealing gasket (17), wherein a cavity (7) is formed between the valve cover (4) and the valve body (1), and characterized in that: The bottom of the valve stem (3) is closed, and a component capable of changing the volume of the cavity (7) is provided on the valve body (1); the component comprises a shell (8), the inner end of the shell (8) is screwed to the valve body (1), the outer end of the shell (8) is provided with an air hole (9), the shell (8) is connected to the cavity (7), and a piston (10) is provided in the shell (8).

2. The brass gate valve with a long service life according to claim 1, characterized in that: The piston (10) includes at least two sealing rings (11) disposed between the piston and the housing (8).

3. The brass gate valve with a long service life according to claim 1 is characterized in that: The outer end of the piston (10) is provided with a weight-reducing blind hole (12).

4. The brass gate valve with a long service life according to claim 1, characterized in that: A loose sealing sleeve (13) is provided in the cavity (7), the upper end of the sealing sleeve (13) is fixed to the valve stem (3), the lower end of the sealing sleeve (13) is fixed to the inner wall of the cavity (7), and the lower end of the sealing sleeve (13) is located at the lower side of the component.

5. The brass gate valve with a long service life according to claim 4, characterized in that: The valve stem (3) is provided with a first annular groove, and an elastic first metal ring (14) is provided in the first annular groove. The first metal ring (14) presses the upper end of the sealing sleeve (13) against the valve stem (3). The inner wall of the cavity (7) is provided with a second annular groove, and an elastic second metal ring (15) is provided in the second annular groove. The second metal ring (15) tightens the lower end of the sealing sleeve (13) against the inner wall of the cavity (7).

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