Eccentric butterfly valve

Abstract

The utility model discloses an eccentric butterfly valve which comprises a valve seat, a valve body, a valve plate, a sealing ring, a valve rod and a driving device capable of driving the valve rod to rotate, the valve body is installed on the valve seat, the valve plate is rotatably installed on the valve body through the valve rod, and the eccentric butterfly valve is characterized in that annular grooves and annular protrusions which are arranged alternately are arranged on the outer side face of the valve plate. The sealing ring comprises a plurality of first sealing rings and a plurality of second sealing rings, the number of the first sealing rings is the same as that of the annular grooves, the first sealing rings and the annular grooves are in one-to-one correspondence, the first sealing rings are annularly arranged in the corresponding annular grooves, and the outer edges of the first sealing rings protrude out of the annular grooves; a second sealing ring is arranged between every two adjacent first sealing rings, and the second sealing rings are arranged on the peripheries of the corresponding annular protrusions in a surrounding mode. The eccentric butterfly valve has excellent sealing performance, leakage is avoided when the eccentric butterfly valve is closed, and the eccentric butterfly valve is more wear-resistant.

Description

Technical Field

[0001] The utility model relates to the field of valves, in particular to an eccentric butterfly valve. Background Art

[0002] The butterfly valve often adopts a triple eccentric structure, that is, the valve stem axis deviates from the valve plate axis, the valve stem axis deviates from the valve body channel center axis, and the valve seat cone surface center line and the valve body channel center axis are at a certain angle. Eccentric butterfly valves are widely used in various station pipelines to adjust flow and cut off fluids.

[0003] However, the current eccentric butterfly valves all use a single-layer sealing ring for sealing. When the sealing ring is worn, it will affect the overall sealing effect. Moreover, since the valve body sealing ring cannot be replaced after being worn, the butterfly valve cannot be used normally. At the same time, the eccentric butterfly valve has the characteristic of becoming tighter as it is closed. Therefore, the sealing ring of some eccentric butterfly valves will reserve a margin in advance to ensure that the valve plate is completely sealed when it is rotated to 90°. This will cause a small gap between the sealing ring and the valve body before the valve plate is completely closed. No matter how fast the closing speed is, gas can easily enter the inner cavity of the butterfly valve. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide an eccentric butterfly valve, which has excellent sealing performance, does not leak when closed, and is more wear-resistant.

[0005] In order to solve the above technical problems, the technical solutions adopted are as follows:

[0006] An eccentric butterfly valve comprises a valve seat, a valve body, a valve plate, a sealing ring, a valve stem and a driving device capable of driving the valve stem to rotate, the valve body is mounted on the valve seat, and the valve plate is rotatably mounted on the valve body through the valve stem, characterized in that: the outer side surface of the valve plate is provided with alternatingly arranged annular grooves and annular protrusions, the sealing ring comprises a plurality of first sealing rings and a plurality of second sealing rings, the number of the first sealing rings is the same as that of the annular grooves and they correspond one to one, the first sealing ring is arranged in the corresponding annular groove, and the outer edge of the first sealing ring protrudes outside the annular groove; a second sealing ring is arranged between two adjacent first sealing rings, and the second sealing ring is arranged on the outer periphery of the corresponding annular protrusion.

[0007] In the above-mentioned eccentric butterfly valve, the first sealing ring and the second sealing ring are alternately arranged on the annular groove and the annular protrusion, so that multi-layer sealing can be achieved. When a single first sealing ring or second sealing ring is worn, resulting in a decrease in the sealing performance at that position, it will not affect the sealing performance of other first sealing rings or second sealing rings. At the same time, the annular grooves and annular protrusions alternately arranged on the outer side of the valve plate can form multiple undulations on the side of the valve plate, which can cooperate with the first sealing ring and the second sealing ring to enhance the sealing performance. In the process of gradual closing of the valve plate, when part of the gas enters the gap, it can also increase the distance of gas flow, providing sufficient time for the valve plate to be completely closed.

[0008] In a preferred embodiment, each of the first sealing rings is provided with a notch, and the notches on each of the first sealing rings are staggered along the circumferential direction. The notch can provide the first sealing ring with a contraction gap and a deformation gap when subjected to high temperature, and by staggering the notches on each of the first sealing rings along the circumferential direction, when part of the gas enters the gap during the gradual closing of the valve plate, the gas flow direction can only flow along the position where the notch is opened, and needs to flow in a circle, further increasing the distance of gas flow, and providing sufficient time for the valve plate to be completely closed.

[0009] In a preferred embodiment, the number of the first sealing rings is four, and the number of the second sealing rings is three.

[0010] In a preferred embodiment, the first sealing ring is a tungsten steel ring, and the second sealing ring is a stainless steel-wrapped graphite ring.

[0011] In a preferred embodiment, the outer edges of the cross sections of the first sealing ring and the second sealing ring are located in the same plane.

[0012] The above-mentioned driving device can adopt the common worm gear, worm and handwheel matching method of eccentric butterfly valve, the worm gear is sleeved on the end of the valve stem, the worm is horizontally arranged and meshed with the worm gear, and the handwheel is installed on the end of the worm; the above-mentioned handwheel can also be replaced by an electric device.

[0013] The beneficial effect of the utility model is that the eccentric butterfly valve has excellent sealing performance and is more wear-resistant. At the same time, when part of the gas enters the gap during the closing process of the valve plate, it is not easy to enter the valve before the valve plate is completely closed. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a structural schematic diagram of an eccentric butterfly valve in an embodiment of the utility model;

[0015] Figure 2 It is a cross-sectional view of the contact position between the valve plate and the valve body in the embodiment of the utility model;

[0016] Figure 3It is a schematic diagram of the structure of the sealing ring in the embodiment of the utility model. DETAILED DESCRIPTION

[0017] The utility model is further described below in conjunction with the accompanying drawings and specific embodiments:

[0018] like Figure 1-3 An eccentric butterfly valve shown in the figure comprises a valve seat 1, a valve body 2, a valve plate 3, a sealing ring 4, a valve stem 5 and a driving device 6 capable of driving the valve stem 5 to rotate, the valve body 2 is mounted on the valve seat 1, the valve plate 3 is rotatably mounted on the valve body 2 through the valve stem 5, the outer side surface of the valve plate 3 is provided with alternatingly arranged annular grooves 301 and annular protrusions 302, the sealing ring 4 comprises a plurality of first sealing rings 401 and a plurality of second sealing rings 402, the number of the first sealing rings 401 and the annular grooves 301 are the same and correspond one to one, the first sealing rings 401 are arranged in the corresponding annular grooves 301, and the outer edges of the first sealing rings 401 protrude outside the annular grooves 301; a second sealing ring 402 is arranged between two adjacent first sealing rings 401, and the second sealing ring 402 is arranged on the outer periphery of the corresponding annular protrusion 302.

[0019] In the above-mentioned eccentric butterfly valve, the first sealing ring 401 and the second sealing ring 402 are alternately arranged on the annular groove 301 and the annular protrusion 302, so that multi-layer sealing can be achieved. When a single first sealing ring 401 or the second sealing ring 402 is worn, resulting in a decrease in the sealing performance at that position, it will not affect the sealing performance of other first sealing rings 401 or second sealing rings 402; at the same time, the annular grooves 301 and the annular protrusions 302 alternately arranged on the outer side of the valve plate 3 can form multiple undulations on the side of the valve plate 3, which can cooperate with the first sealing ring 401 and the second sealing ring 402 to enhance the sealing performance, and in the process of gradual closing of the valve plate 3, when part of the gas enters the gap, it can also increase the distance of gas flow, thereby providing sufficient time for the valve plate 3 to be completely closed.

[0020] Each first sealing ring 401 is provided with a notch 4011, and the notches 4011 on each first sealing ring 401 are staggered in the circumferential direction. The notches 4011 can provide the first sealing ring 401 with a contraction gap and a deformation gap when subjected to high temperature, and by staggering the notches 4011 on each first sealing ring 401 in the circumferential direction, when part of the gas enters the gap during the gradual closing process of the valve plate 3, the gas can only flow along the position where the notch 4011 is opened, and needs to flow in a circle, further increasing the distance of gas flow, and providing sufficient time for the valve plate 3 to be completely closed.

[0021] The first sealing ring 401 is made of a tungsten steel ring, and the second sealing ring 402 is made of a graphite ring with a stainless steel edge.

[0022] The outer edges of the cross sections of the first sealing ring 401 and the second sealing ring 402 are all in the same plane.

[0023] The driving device 6 adopts the common worm gear, worm and hand wheel matching mode of eccentric butterfly valve. The worm gear is sleeved on the end of the valve stem 5, the worm is horizontally arranged and meshed with the worm gear, and the hand wheel is installed on the end of the worm gear.

Claims

1. An eccentric butterfly valve, comprising a valve seat, a valve body, a valve plate, a sealing ring, a valve stem and a driving device capable of driving the valve stem to rotate, wherein the valve body is mounted on the valve seat, and the valve plate is rotatably mounted on the valve body through the valve stem, characterized in that: The outer side surface of the valve plate is provided with alternatingly arranged annular grooves and annular protrusions, and the sealing ring includes a plurality of first sealing rings and a plurality of second sealing rings. The number of first sealing rings is the same as that of the annular grooves and they correspond one to one. The first sealing rings are arranged in the corresponding annular grooves, and the outer edges of the first sealing rings protrude outside the annular grooves; a second sealing ring is arranged between two adjacent first sealing rings, and the second sealing ring is arranged on the outer periphery of the corresponding annular protrusion.

2. An eccentric butterfly valve according to claim 1, characterized in that: Each of the first sealing rings is provided with a notch, and the notches on each of the first sealing rings are staggered with each other along the circumferential direction.

3. An eccentric butterfly valve according to claim 1, characterized in that: The number of the first sealing rings is four, and the number of the second sealing rings is three.

4. An eccentric butterfly valve according to claim 1, characterized in that: The first sealing ring is a tungsten steel ring, and the second sealing ring is a stainless steel-wrapped graphite ring.

5. An eccentric butterfly valve according to claim 1, characterized in that: The outer edges of the cross sections of the first sealing ring and the second sealing ring are located in the same plane.

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