Axial-flow type check valve with replaceable sealing pair

Abstract

The utility model discloses an axial-flow type check valve with a replaceable sealing pair, which relates to the field of valves and comprises a valve body provided with an inlet cavity and an inner cavity communicated with the inlet cavity, and the inner wall, close to the inlet cavity, of the valve body protrudes inwards in the radial direction to form a flow guide step; the valve seat is detachably installed on the side, away from the inlet cavity, of the flow guide step, and a sealing ring is embedded in the valve seat; the flow guide cover is fixed to the side, away from the inlet cavity, of the valve body, and a shaft hole is formed in the part, extending into the inner cavity, of the flow guide cover. And a guide rod is arranged at the tail of the valve clack, the guide rod is installed in the shaft hole in a sliding mode, a spring is arranged between the shaft hole and the valve clack, and the spring stretches in the natural state to tightly press the surface of the valve clack and the sealing ring, so that sealing is achieved. By improving the structure of the valve seat sealing pair, the sealing reliability is improved, the stable flow state is maintained, and the valve seat sealing structure is more economical.

Description

Technical Field

[0001] The utility model relates to the field of valves, in particular to an axial flow check valve with a replaceable sealing pair. Background Art

[0002] Axial flow check valve is often used to prevent the backflow of media in the pipeline from causing water hammer and damage to the power pump. Compared with ordinary check valves, it is also designed with a shock-absorbing spring, and the soft and hard sealing structure of the valve seat has noise reduction and shock-absorbing effects.

[0003] At present, the axial flow check valves commonly used in the market have sealing rings embedded in the valve disc and directly seal with the valve body. This places high demands on the processing technology of the sealing surface on the valve body, and there is also a risk of the sealing ring on the valve disc falling off. If the sealing surface on the valve body is damaged, the entire valve needs to be replaced, and the maintenance cost is high. Utility Model Content

[0004] The purpose of the utility model is to overcome the deficiencies of the prior art and to provide an axial flow check valve with a replaceable sealing pair, which improves the structure of the valve seat sealing pair, enhances the sealing reliability, maintains a stable flow state, and is more economical.

[0005] The purpose of the utility model is achieved through the following technical solutions: the axial flow check valve with replaceable sealing pair comprises:

[0006] The valve body comprises an inlet cavity and an inner cavity communicating with the inlet cavity, wherein the inner wall of the valve body close to the inlet cavity protrudes radially inward to form a flow guide step;

[0007] The valve seat is detachably mounted on the guide step and on the side away from the inlet cavity, and a sealing ring is embedded on the valve seat;

[0008] A flow guide cover is fixed to a side of the valve body away from the inlet cavity, and a shaft hole is provided at a portion of the flow guide cover extending into the inner cavity; and

[0009] The valve disc has a guide rod at its tail end, which is slidably installed in the shaft hole, and a spring is arranged between the shaft hole and the valve disc. In a natural state, the spring stretches to press the surface of the valve disc against the sealing ring to achieve sealing.

[0010] As a further technical solution, a hard sealing surface is provided on the surface of the valve seat. When high-pressure water hammer occurs, the valve disc compresses the sealing ring to be parallel to the hard sealing surface, and the valve seat and the valve disc form a soft and hard sealing structure to achieve sound elimination and shock absorption.

[0011] As a further technical solution, a groove is provided on the side of the valve seat facing the flow guide step for installing an O-ring.

[0012] As a further technical solution, corresponding openings are provided on the valve seat and the diversion step for installing fixing bolts to fixedly connect the valve body and the valve seat.

[0013] As a further technical solution, the valve body and the flange at the bottom of the diversion cover are fixed by locking bolts.

[0014] As a further technical solution, a bushing is installed in the shaft hole, and the bushing is sleeved on the guide rod.

[0015] As a further technical solution, spring seats are provided on both the shaft hole and the valve flap, and the two spring seats are coaxially arranged.

[0016] The beneficial effects of the present utility model are as follows:

[0017] 1. The valve seat is detachably installed on the valve body. If there is a long-term operation or foreign matter jamming the sealing surface or the valve seat sealing surface, the valve seat can be separately disassembled and replaced without replacing the whole valve, and the maintenance cost is lower;

[0018] 2. The sealing ring is arranged in the embedding groove of the valve seat, which has the effect of preventing falling off. When the medium in the pipeline flows back, the valve flap acts on the sealing ring of the valve seat to form a seal. When a high-pressure water hammer occurs, the sealing ring is compressed to be parallel to the hard sealing surface of the valve seat. At this time, the valve flap and the valve seat body form a seal, and the structure of the hard and soft seals has the effects of noise reduction and shock absorption;

[0019] 3. An O-ring seal is provided between the valve seat and the valve body (diversion step) to prevent the medium from entering the valve cavity through the gap between the valve seat and the valve body when the medium flows forward. When the medium flows backward, this O-ring also serves as the second seal of the valve seat. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic structural diagram of the present utility model.

[0021] Figure 2 is Figure 1 a partial enlarged schematic diagram of area A in

[0022] Description of the reference numerals: valve body 1, valve seat 2, sealing ring 3, O-ring 4, valve flap 5, diversion cover 6, spring 7, bushing 8, fixing bolt 101, locking bolt 102, inlet cavity 201, inner cavity 202, hard sealing surface 203, diversion step 301, guide rod 501, shaft hole 601. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The following will introduce the present utility model in detail with reference to the drawings:

[0024] Embodiment: As shown in the attached Figure 1 , 2As shown, the axial flow check valve with replaceable sealing pair includes a valve body 1, a valve seat 2, a sealing ring 3, an O-ring 4, a valve disc 5, a flow guide cover 6, a spring 7, a sleeve 8, a fixing bolt 101, a locking bolt 102, an inlet chamber 201, an inner chamber 202, a hard sealing surface 203, a flow guide step 301, a guide rod 501 and an axial hole 601.

[0025] Reference Figure 1 The left side of the valve body 1 is the inlet chamber 201, and the right side is the inner chamber 202. The inlet chamber 201 is connected to the inner chamber 202. The inner wall of the valve body 1 near the inlet chamber 201 bulges radially inward to form a guide step 301. The rear side of the guide step 301 (i.e., the side away from the inlet chamber 201) is used as the installation position of the valve seat 2. Figure 2 As shown, corresponding holes are opened on the valve seat 2 and the flow guide step 301 for installing the fixing bolts 101, so that the valve seat 2 can be detachably installed on the flow guide step 301 (valve body 1). Preferably, a slot is opened on the valve seat 2, and a sealing ring 3 is embedded in the slot. Since the valve seat 2 can be detachably installed on the valve body 1, if it is operated for a long time or there are foreign objects stuck on the sealing surface or the valve seat sealing surface, the valve seat 2 can be removed and replaced separately without replacing the entire valve, and the maintenance cost is lower. In addition, the sealing ring 3 is installed in the slot of the valve seat, which has an anti-falling effect. Furthermore, a groove is set on the side of the valve seat 2 facing the flow guide step 301, and an O-ring 4 is installed in the groove. The O-ring 4 is used to form a seal between the valve seat 2 and the valve body 1 (flow guide step 301) to prevent the medium from entering the valve cavity through the gap between the valve seat 2 and the valve body 1 when the medium flows forward. When the medium flows back, this O-ring 4 also serves as the second seal of the valve seat 2.

[0026] Furthermore, the flanges at the bottom of the valve body 1 and the guide cover 6 are fixed by locking bolts 102, so that the guide cover 6 is installed on the side of the valve body 1 away from the inlet cavity 201. At the same time, an axial hole 601 is set at the part of the guide cover 6 extending into the inner cavity 202, and a shaft sleeve 8 is installed in the axial hole 601 with interference fit, and the shaft sleeve 8 is sleeved on the guide rod 501 at the tail of the valve disc 5. The guide rod 501 is slidably installed in the axial hole 601, and a spring seat is set on the axial hole 601 and the valve disc 5, and the two spring seats are coaxially arranged. A spring 7 is set between the axial hole 601 and the valve disc 5 (that is, between the two spring seats). In the natural state, the spring 7 is stretched to press the surface of the valve disc 5 and the sealing ring 3 to achieve sealing.

[0027] like Figure 2 As shown, the surface of the valve disc 5 adopts a spherical arc surface, and a hard sealing surface 203 is set on the surface of the valve seat 2. When high-pressure water hammer occurs, the valve disc 5 compresses the sealing ring 3 to be parallel to the hard sealing surface 203, and the valve seat 2 and the valve disc 5 form a soft and hard sealing structure to achieve sound elimination and shock absorption.

[0028] The working process of this utility model:

[0029] When the source water pump is turned on, the medium enters the inlet cavity 201 of the valve body 1. After passing through the diversion step 301, the medium is diverted to flow towards the valve flap 5. The static pressure of the medium acts on the valve flap 5. When this pressure is greater than the pre-tightening force of the spring 7, the flow channel opens. Because the axial check valve has a small stroke and the flow channel becomes narrower, the flow velocity increases and the pressure decreases at this time. A pressure difference is formed between the inlet cavity 201 and the inner cavity 202. Under the combined action of the static pressure acting on the valve flap 5 and the pressure difference before and after, the valve flap 5 overcomes the acting force of the spring 7 and pushes the valve flap 5 to continue to open the valve until the valve is fully open. If the flow velocity of the medium decreases and the acting force of the spring 7 is greater than the static pressure on the valve flap 5, the valve makes a closing movement. When the flow velocity drops to 0, because the axial check valve has a small stroke, the valve flap 5 closes quickly to prevent the medium from flowing back. When a water hammer wave occurs in the pipeline, because the sealing pair (valve seat 2 and valve flap 5) is a soft-hard sealing structure, it has the effects of noise elimination and shock absorption. In addition, since the valve seat 2 is detachably installed on the valve body 1, if it operates for a long time or there is a foreign object scratching the sealing surface or the valve seat sealing surface, the valve seat 2 can be separately disassembled and replaced without replacing the whole valve, and the maintenance cost is lower.

[0030] It can be understood that for those skilled in the art, any equivalent replacement or change to the technical solution and the inventive concept of the present utility model should fall within the protection scope of the claims attached to the present utility model.

Claims

1. An axial flow check valve with replaceable sealing pair, characterized in that, Comprising: A valve body (1) having an inlet cavity (201) and an inner cavity (202) communicating with the inlet cavity (201). A flow guiding step (301) is formed by the inner wall of the valve body (1) near the inlet cavity (201) protruding radially inward; A valve seat (2) detachably mounted on the side of the flow guiding step (301) facing away from the inlet cavity (201). A sealing ring (3) is inlaid on the valve seat (2); A flow guiding cover (6) fixed on the side of the valve body (1) away from the inlet cavity (201), and a shaft hole (601) is provided in the part of the flow guiding cover (6) extending into the inner cavity (202); and A valve flap (5) with a guide rod (501) provided at its tail. The guide rod (501) is slidably mounted in the shaft hole (601), and a spring (7) is provided between the shaft hole (601) and the valve flap (5). In the natural state, the spring (7) extends to press the surface of the valve flap (5) against the sealing ring (3) to achieve sealing.

2. The axial flow check valve with replaceable sealing pair according to claim 1, characterized in that: A hard sealing surface (203) is provided on the surface of the valve seat (2). When high-pressure water hammer occurs, the valve flap (5) compresses the sealing ring (3) to be parallel to the hard sealing surface (203), and the valve seat (2) and the valve flap (5) form a hard-soft sealing structure to achieve noise reduction and shock absorption.

3. The axial flow check valve with replaceable sealing pair according to claim 1, characterized in that: A groove is provided on the side of the valve seat (2) facing the flow guiding step (301) for installing an O-ring (4).

4. The axial flow check valve with replaceable sealing pair according to claim 1, characterized in that: Corresponding openings are provided on the valve seat (2) and the flow guiding step (301) for installing fixing bolts (101) to fixedly connect the valve body (1) and the valve seat (2).

5. The axial flow check valve with replaceable sealing pair according to claim 1, characterized in that: The valve body (1) and the flange at the bottom of the flow guiding cover (6) are fixed by locking bolts (102).

6. The axial flow check valve with replaceable sealing pair according to claim 1, characterized in that: A shaft sleeve (8) is installed in the shaft hole (601), and the shaft sleeve (8) is sleeved on the guide rod (501).

7. The axial flow check valve with replaceable sealing pair according to claim 1, characterized in that: Spring seats are provided on both the shaft hole (601) and the valve flap (5), and the two spring seats are coaxially arranged.

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