Eccentric soft sealing butterfly valve

Abstract

The utility model discloses an eccentric soft sealing butterfly valve. The butterfly valve comprises a valve body, a butterfly plate arranged in an inner cavity of the valve body, a valve rod arranged on the butterfly plate, a valve seat arranged between the valve body and the butterfly plate and used for achieving clearance sealing, and a supporting pressing ring arranged on an inner ring of the valve seat and used for limiting deviation of the valve seat. An elastic piece is arranged on the side, making contact with the valve body, of the valve seat, the sealing face of the butterfly plate and the valve seat is a spherical face, the sphere center of the sealing face and the center line of the valve rod are eccentrically arranged, an eccentric distance is formed between the sphere center of the sealing face and the center line of the valve rod, the projection of the eccentric distance in the Y direction is a first eccentric distance, and the projection of the eccentric distance in the X direction is a second eccentric distance. The ball center of the sealing face is located on the center line of a medium flow channel of the butterfly valve. According to the butterfly valve, deviation of the valve seat can be limited, abrasion and deformation of the valve seat can be reduced, the sealing performance between the valve seat and the butterfly plate is improved, and the inner leakage phenomenon is prevented.

Description

[Technical Field]

[0001] This utility model belongs to the field of butterfly valve technology, and in particular relates to an eccentric soft-seal butterfly valve. [Background Technology]

[0002] When a butterfly valve is operated at high frequency, there is mutual squeezing and scraping between the valve seat and the butterfly plate. After the butterfly valve is opened, the butterfly plate cannot quickly detach from the sealing surface of the valve seat. Moreover, due to the uneven pressure caused by long-term squeezing, a certain point of the valve seat wears and breaks down quickly due to stress concentration. This results in insufficient sealing pressure between the valve seat and the butterfly plate, causing internal leakage.

[0003] To address the aforementioned issues, Chinese Patent Publication No. CN212564441U discloses a deformable spherical eccentric double-seal valve. The valve seat and sealing ring close to form a sealing surface. This sealing surface is curved, and its radial cross-section is a perfect circle. The oblique line formed by the center of this circle forms an angle α with the valve flow channel centerline. The plane formed by the oblique line and the valve flow channel centerline is perpendicular to the valve stem axis. The valve stem axis is eccentrically positioned relative to the valve flow channel centerline. The center of one radial cross-section of the sealing surface, the one furthest from the valve stem, is also on the valve flow channel centerline. When the oblique line coincides with the valve flow channel centerline, the sealing surface is spherical, and the sealing ring is part of a sphere. The center of this sphere is on the valve flow channel centerline. This eccentric structure allows the butterfly plate to quickly disengage from the valve body's sealing surface after the valve is opened. Furthermore, while the butterfly plate can tighten further when the valve is closed, this design uses an annular steel plate and a valve seat to achieve a seal between the butterfly plate and the valve seat. The inner side of the annular steel plate is designed with a sharp corner to form a line seal with the butterfly plate. After long-term opening and closing, the sharp corner of the annular steel plate will scratch the outer ring of the butterfly plate, affecting the sealing effect. Moreover, the inner diameter side of the annular steel plate is an elastic end, which will squeeze the valve seat from side to side, causing the valve seat to shift in the left and right directions. In addition, there is a countersunk screw on the right side of the valve seat, which is pressed against the middle of the valve seat. The compression of the butterfly plate and the impact force of the medium will cause the middle of the valve seat to bend to the left and the upper and lower ends to bend to the right. When the butterfly plate squeezes the valve seat, due to the irregular deformation of the valve seat, the force on the valve seat is uneven and different positions are worn to different degrees, which leads to the failure of the seal between the valve seat and the butterfly plate and causes internal leakage.

[0004] Therefore, it is necessary to provide an eccentric soft-seal butterfly valve to solve the above-mentioned technical problems. [Utility Model Content]

[0005] The main purpose of this utility model is to provide an eccentric soft-seal butterfly valve that can limit the offset of the valve seat, reduce the wear and deformation of the valve seat, improve the sealing performance between the valve seat and the butterfly plate, and prevent internal leakage.

[0006] This utility model achieves the above-mentioned objective through the following technical solution: an eccentric soft-seal butterfly valve, comprising a valve body, a butterfly plate disposed in the inner cavity of the valve body, a valve stem disposed on the butterfly plate, a valve seat disposed between the valve body and the butterfly plate for achieving gap sealing, and a support pressure ring disposed on the inner ring of the valve seat for limiting the offset of the valve seat. The valve seat has an elastic element disposed on the contact side with the valve body. The sealing surface between the butterfly plate and the valve seat is spherical. The center of the sphere of the sealing surface is eccentrically disposed with respect to the center line of the valve stem and forms an eccentric distance. The projection of the eccentric distance in the Y direction is the first eccentric distance, and the projection in the X direction is the second eccentric distance. The center of the sphere of the sealing surface is on the center line of the medium flow channel of the butterfly valve.

[0007] Furthermore, a limiting part is provided on one side of the valve body cavity to restrict the reverse rotation of the butterfly plate, and a guide groove is provided on the other side to facilitate the rotation of the butterfly plate. The distance from the center line of the valve stem to the limiting part is less than the distance from the center line of the valve stem to the guide groove, and the center line of the valve stem is offset to the side away from the valve seat.

[0008] Furthermore, a first limiting groove and a second limiting groove are provided on both sides of the support pressure ring. A limiting support is provided between the first limiting groove and the second limiting groove, which separates the first limiting groove and the second limiting groove and extends towards the outer ring of the valve seat. A first floating arm extending into the first limiting groove and a second floating arm extending into the second limiting groove are correspondingly provided on the inner side of the valve seat. A third limiting groove that cooperates with the limiting support is provided between the first floating arm and the second floating arm.

[0009] Furthermore, the width of the first floating arm is less than the width of the first limiting groove, and the width difference between the first floating arm and the first limiting groove is the floating gap for the first floating arm to move left and right.

[0010] Furthermore, the valve seat also includes a first sealing surface that achieves a gap seal with the butterfly plate, and a first mating surface that mates with the valve body and is horizontal, and a second mating surface that is vertical.

[0011] Furthermore, an annular groove is provided at the position where the first mating surface connects to the second mating surface, and the elastic element is disposed within the annular groove.

[0012] Furthermore, the elastic element is an O-ring.

[0013] Compared with the prior art, the beneficial effects of this eccentric soft-seal butterfly valve are as follows:

[0014] (1) The sealing surface between the butterfly plate and the valve seat is a spherical surface. The center of the sphere of the sealing surface is eccentrically set with the center line of the valve stem and forms an eccentricity. The projection of the eccentricity in the Y direction is the first eccentricity distance, and the projection in the X direction is the second eccentricity distance. The setting of the first eccentricity distance and the second eccentricity distance can make the butterfly plate enter and leave smoothly. When sealing is required, it will tighten more and more to ensure sealing and reduce torque. When opening the butterfly plate, it can also leave quickly, which can reduce the wear of the valve seat.

[0015] (2) The support ring is supported on the inner ring of the valve seat. The inner ring of the valve seat and the support ring are in a groove and protrusion fit relationship to support the valve seat and prevent the valve seat from moving up and down. At the same time, it can also limit the valve seat from moving left and right, so as to realize the support and limit of the valve seat by the support ring, ensure the seal between the valve seat and the butterfly plate, and prevent the occurrence of internal leakage.

[0016] (3) The elastic element cooperates with the valve seat and provides pre-tightening force to the valve seat. On the one hand, the elastic element on the valve seat can ensure sufficient pre-tightening force between the butterfly plate and the valve seat, so that the first sealing surface of the valve seat can seal with the butterfly plate. On the other hand, the deformation of the elastic element can offset part of the compression deformation of the valve seat, prevent the valve seat from generating cold flow deformation and reducing the rebound force. The elastic element can ensure that the valve seat does not undergo cold flow deformation under high frequency switching and in the temperature range of -46 to 200℃, so that the sealing performance between the valve seat and the butterfly plate is more stable. [Attached Image Description]

[0017] Figure 1 This is a front view of the eccentric soft-seal butterfly valve according to an embodiment of the present utility model;

[0018] Figure 2 This is a rear view of the eccentric soft-seal butterfly valve according to an embodiment of the present invention;

[0019] Figure 3 This is an embodiment of the present utility model. Figure 2 Schematic diagram of the cross-sectional structure at point AA;

[0020] Figure 4 This is an embodiment of the present utility model. Figure 3 Enlarged structural diagram of section B in the middle;

[0021] The numbers in the image represent:

[0022] 100-Eccentric soft-seal butterfly valve;

[0023] 1-Valve body; 11-Limiting part; 12-Guide groove; 2-Butterfly plate; 3-Valve stem;

[0024] 4-Valve seat, 41-First floating arm, 42-Third limiting groove, 43-Second floating arm, 44-First sealing surface, 45-First mating surface, 46-Second mating surface;

[0025] 5-Supporting pressure ring, 51-First limiting groove, 52-Limiting support, 53-Second limiting groove, 54-Floating gap; 6-Elastic element.

Detailed Implementation Methods

[0026] Please refer to Figures 1-4 This embodiment is an eccentric soft-seal butterfly valve 100. The eccentric soft-seal butterfly valve 100 includes a valve body 1, a butterfly plate 2 disposed within the inner cavity of the valve body 1, a valve stem 3 disposed on the butterfly plate 2, a valve seat 4 disposed between the valve body 1 and the butterfly plate 2 for achieving a gap seal, and a support pressure ring 5 disposed within the inner ring of the valve seat 4 for limiting the offset of the valve seat 4. An elastic element 6 is provided on the contact side of the valve seat 4 with the valve body 1. The elastic element 6 provides a preload force to the valve seat 4 to achieve a seal between the valve seat 4 and the butterfly plate 2. The sealing surface of the butterfly plate 2 and the valve seat 4 is spherical. The center of the sphere of the sealing surface is eccentrically positioned with respect to the centerline of the valve stem 3, forming an eccentricity. The projection of the eccentricity in the Y direction is the first eccentricity distance, and the projection in the X direction is the second eccentricity distance. The center of the sphere of the sealing surface is located on the centerline of the butterfly valve's medium flow channel. The direction in which the butterfly valve's medium flow channel extends is the Y direction, the direction perpendicular to the butterfly valve's medium flow channel is the X direction, and the direction in which the valve stem 3 extends is the Z direction.

[0027] One side of the inner cavity of the valve body 1 is provided with a limiting part 11 to restrict the reverse rotation of the butterfly plate 2, and the other side is provided with a guide groove 12 to facilitate the rotation of the butterfly plate 2. The distance from the center line of the valve stem 3 to the limiting part 11 is less than the distance from the center line of the valve stem 3 to the guide groove 12. The difference between the two distances is twice the second eccentric distance, that is, the valve stem 3 is biased towards the limiting part 11, which enables the butterfly plate 2 to quickly disengage from the valve seat 4 during the opening process, thereby reducing the frictional torque during the switching process and reducing the wear of the valve seat 4. At the same time, the central axis of the valve stem 3 is offset away from the side of the valve seat 4. When the butterfly plate 2 is closed, the distance between the center line of the valve stem 3 and the Y plane where the center of the sealing surface is located is the first eccentric distance. Due to the existence of this first eccentric distance, when the butterfly plate 2 rotates and squeezes into the valve seat 4, the entire sealing surface of the valve seat 4 is subjected to uniform force, which reduces the wear and damage caused by unbalanced stress on the sealing surface between the valve seat 4 and the butterfly plate 2. Moreover, when the butterfly plate 2 rotates, it can squeeze the valve seat 4 tighter and tighter, avoiding internal leakage caused by insufficient compression deformation. Therefore, the setting of the first eccentric distance and the second eccentric distance allows the butterfly plate 2 to enter and leave smoothly. When sealing is required, it will tighten more and more as it is turned to ensure a seal, and it can also reduce torque. When opening the butterfly plate 2, it can also leave quickly, which can reduce the wear of the valve seat 4.

[0028] The support ring 5 is supported on the inner ring of the valve seat 4. The inner ring of the valve seat 4 and the support ring 5 are in a groove and protrusion fit relationship, which supports the valve seat 4 to prevent the valve seat 4 from moving up and down, and at the same time restricts the valve seat 4 from moving left and right. The support ring 5 supports and limits the valve seat 4, ensures the seal between the valve seat 4 and the butterfly plate 2, and prevents internal leakage.

[0029] The support ring 5 has a first limiting groove 51 and a second limiting groove 53 on both sides. A limiting support 52 is provided between the first limiting groove 51 and the second limiting groove 53, which separates the first limiting groove 51 and the second limiting groove 53 and extends towards the outer ring of the valve seat 4. Correspondingly, the inner side of the valve seat 4 has a first floating arm 41 extending into the first limiting groove 51 and a second floating arm 43 extending into the second limiting groove 53. A third limiting groove 42 is provided between the first floating arm 41 and the second floating arm 43, which cooperates with the limiting support 52. The limiting support 52 is stuck between the first floating arm 41 and the second floating arm 43, which can not only support the valve seat 4, but also limit the left and right displacement of the valve seat 4. The width of the first floating arm 41 is less than the width of the first limiting groove 51. The width difference between the first floating arm 41 and the first limiting groove 51 is the floating gap 54 for the first floating arm 41 to move left and right. When the butterfly plate 2 squeezes the valve seat 4, the first floating arm 41 can float left and right within the floating gap 54 in order to achieve a gap seal between the valve seat 4 and the butterfly plate 2.

[0030] The valve seat 4 also includes a first sealing surface 44 that achieves a gap seal with the butterfly plate 2, and a first mating surface 45 that mates with the valve body 1 and is horizontal, and a second mating surface 46 that is vertical. The first mating surface 45 and the second mating surface 46 are connected by an annular groove. An elastic element 6 is disposed in the annular groove. The elastic element 6 mates with the valve seat 4 and provides a preload force to the valve seat 4. On the one hand, the elastic element 6 on the valve seat 4 can ensure sufficient preload force between the butterfly plate 2 and the valve seat 4, so that the first sealing surface 44 of the valve seat 4 and the butterfly plate 2 can achieve a seal. On the other hand, the deformation of the elastic element 6 can offset part of the compression deformation of the valve seat 4, preventing the valve seat 4 from having cold flow deformation and reduced rebound force. The elastic element 6 can ensure that the valve seat 4 does not undergo cold flow deformation under high-frequency switching and in a temperature range of -46 to 200°C, making the sealing performance between the valve seat 4 and the butterfly plate 2 more stable. In this embodiment, the elastic element 6 is an O-ring. In other embodiments, the elastic element 6 can be set as a spring, a covered spring, an elastic sealing ring, etc., as long as it is an elastic element that can provide preload to the valve seat 4. The specific structure used is not limited here, and can be set according to the actual situation.

[0031] The above descriptions are merely some embodiments of this utility model. For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of this utility model, and all such modifications and improvements fall within the protection scope of this utility model.

Claims

1. An eccentric soft seal butterfly valve characterized by: The valve comprises a valve body, a butterfly plate arranged in the inner cavity of the valve body, a valve rod arranged on the butterfly plate, a valve seat arranged between the valve body and the butterfly plate and used for realizing gap sealing, and a support pressing ring arranged in the inner ring of the valve seat and used for limiting the deviation of the valve seat, the valve seat is provided with an elastic member on the contact side with the valve body, the sealing surfaces of the butterfly plate and the valve seat are spherical surfaces, the spherical center of the sealing surface is arranged eccentrically with the center line of the valve rod and forms an eccentricity, the projection of the eccentricity in the Y direction is a first eccentric distance and the projection in the X direction is a second eccentric distance, and the spherical center of the sealing surface is on the center line of the butterfly valve medium flow channel.

2. An eccentric soft seal butterfly valve as claimed in claim 1, wherein: A limiting part for limiting the reverse rotation of the butterfly plate is arranged on one side of the inner cavity of the valve body and a guide groove for facilitating the rotation of the butterfly plate is arranged on the other side, the distance from the center line of the valve rod to the limiting part is smaller than the distance from the center line of the valve rod to the guide groove, and the center line of the valve rod deviates away from the valve seat.

3. An eccentric soft seal butterfly valve as claimed in claim 1, wherein: First and second limiting grooves are arranged on both sides of the support pressing ring, a limiting support extending to the outer ring of the valve seat is arranged between the first and second limiting grooves to separate the first and second limiting grooves, and the inner side of the valve seat is correspondingly provided with a first floating arm extending into the first limiting groove and a second floating arm extending into the second limiting groove, and a third limiting groove cooperating with the limiting support is arranged between the first and second floating arms.

4. An eccentric soft seal butterfly valve as claimed in claim 3, wherein: The width of the first floating arm is smaller than the width of the first limiting groove, and the width difference between the first floating arm and the first limiting groove is a floating gap for the left and right movement of the first floating arm.

5. An eccentric soft seal butterfly valve as claimed in claim 1, wherein: The valve seat further comprises a first sealing surface realizing gap sealing with the butterfly plate, and a first mating surface and a second mating surface horizontally and vertically cooperating with the valve body.

6. An eccentric soft seal butterfly valve as claimed in claim 5, wherein: An annular accommodation groove is arranged at the position where the first mating surface and the second mating surface are connected, and the elastic member is arranged in the annular accommodation groove.

7. An eccentric soft seal butterfly valve as claimed in claim 1, wherein: The elastic member is an O-ring.

Images