Bidirectional soft sealing knife type gate valve

Abstract

The utility model discloses a bidirectional soft sealing knife type gate valve which comprises a valve body and a valve plate, the valve plate is in a U shape, the lower end of the valve plate abuts against a valve seat inner ring arranged in a sealing groove formed in the valve body when the valve is closed, the valve seat is embedded in the inner ring and the outer ring of the sealing groove and abuts against the bottom of the sealing groove, and the valve seat comprises a steel ring and a rubber strip wrapping the outer side of the steel ring. The number of the steel rings is two, the valve seat comprises an abutting face protruding relative to the valve plate and a sealing face opposite to the sealing groove, and the abutting face and the outer ring face of the valve plate are arranged in an attached and sealed mode. According to the knife type gate valve, the valve seat is flexibly sealed, and the steel ring is lined in the rubber strip, so that the strength of the valve seat is improved, the gate valve can stably work for a long time under the working condition of high pressure difference, the U-shaped gate plate and the valve seat are used for quickly cutting off a medium flow channel in the radial direction, the blockage of the flow channel in the gate valve is small, the medium flows smoothly, and the service life of the gate valve is prolonged. And the problems of medium retention and blockage are not easy to generate, and the smooth circulation also enables the medium conveying pressure loss to be small.

Description

Technical Field

[0001] The utility model relates to the technical field of gate valves, and particularly relates to a two-way soft-sealing knife gate valve. Background Art

[0002] A knife gate valve (also known as a knife valve and a slurry valve) is a special designed cut-off valve, mainly used for handling media containing solid particles, fibers or high viscosity. The knife gate valve entered China in the 1980s. In less than two decades, its application range has expanded from ordinary fields to a wider range of industries, from coal washing, gangue discharging and slag discharging in mines and power plants to urban sewage treatment, and from general industrial pipelines to food, hygiene, medicine and other professional pipeline systems.

[0003] The knife gate valve has a simple structure, generally consisting of a valve body, a valve stem, a gate plate and a driving unit. The driving unit drives the valve stem to push the gate plate to move relative to the valve body, so as to open and close the valve passage to achieve the purpose of cutting off the medium flow passage. During the use of the valve, the sealing is mainly realized by the sealing cooperation between the gate plate of the gate valve and the valve seat on the valve body. Content of the Utility Model

[0004] The purpose of the utility model is to provide a newly designed two-way sealing knife gate valve, which improves the strength of the valve seat by embedding a steel ring in the soft seal of the valve seat, enhances the sealing retention force and prolongs the service life of the gate valve.

[0005] The technical solution adopted by the utility model is as follows: a two-way soft-sealing knife gate valve, including a valve body and a valve plate. The valve plate is U-shaped. When the valve is closed, the lower end abuts against the inner ring of the valve seat arranged in the sealing groove on the valve body. The valve seat is embedded in the outer ring of the sealing groove and abuts against the bottom of the sealing groove. The valve seat includes a steel ring and a rubber strip coated on the outside of the steel ring. There are two steel rings. The valve seat includes a butting surface protruding relative to the valve plate and a sealing surface relative to the sealing groove. The butting surface is hermetically arranged in fit with the outer ring surface of the valve plate.

[0006] Further, the valve plate and the valve seat are hermetically arranged in interference fit. The valve seat is arranged with an open upper end in a U shape. The embedded steel ring is in a U-shaped elastic flare. The rubber strip is coated outside the steel ring. The steel ring is elastically expanded to clamp the rubber strip outside the valve seat with the bottom of the sealing groove to maintain installation and sealing.

[0007] Further, a pressing strip and packing are also arranged on the valve body. The packing is sleeved outside the valve plate in a ring shape and is pressed by the pressing strip in the material groove at the open upper end of the valve body. The pressing strip is fixed relative to the valve body through bolts to seal the open upper end.

[0008] Further, a bracket and a valve stem are also provided on the valve body. A handwheel is provided on the bracket and is axially fixed and circumferentially rotatable relative to the bracket. The handwheel is provided with an internally threaded copper sleeve, and the valve stem is provided with an externally threaded portion and is arranged in threaded fit with the internally threaded copper sleeve. The lower end of the valve stem is fixedly arranged with the valve plate through a fixing pin.

[0009] Further, a medium flow channel is provided on the valve body, and a gate cavity is also provided inside the valve body. The diameter of the medium flow channel is smaller than that of the gate cavity. The sealing groove is arranged at the edge of the gate cavity, and a stop block protruding towards the middle is provided at the opening of the sealing groove.

[0010] Further, edge cleaning grooves are provided on both sides of the abutting surface relative to the valve plate, and the abutting surface between the two edge cleaning grooves is arranged to fit the contour of the valve plate.

[0011] Beneficial effects: For the knife gate valve of the present utility model, by providing a soft seal valve seat and designing a way of lining a steel ring inside a rubber strip, the strength of the valve seat is improved, ensuring that the gate valve can work stably for a long time under high pressure difference conditions. The U-shaped gate plate and the valve seat, through the lifting of the gate plate driven by the valve stem, quickly cut off the medium flow channel radially. The sealing states on both sides of the medium flow channel are the same to achieve double-sided sealing. The design of the soft seal rubber strip can make up for the small deviation in the sealing fit between the valve seat and the valve plate. The setting of the edge groove guides the extrusion stress and reduces the problem of over-strong local extrusion. Moreover, the internal flow channel of the gate valve in this embodiment has less obstruction, the medium flows smoothly, and it is not easy to generate problems such as medium retention and blockage. The smooth flow also makes the pressure loss of the medium transportation small, improving the use performance. Description of the Drawings

[0012] Figure 1 It is a schematic structural diagram of the double-sided soft seal knife gate valve of the present utility model.

[0013] Figure 2 It is a schematic structural diagram of the gate valve assembly of the present utility model.

[0014] Figure 3 It is a sectional view of the gate valve structure of this embodiment.

[0015] Figure 4 It is a schematic diagram of the cooperation between the valve plate and the valve seat of this embodiment.

[0016] Reference numerals: 1, valve body; 11, sealing groove; 111, stop block; 12, pressing strip; 13, packing; 14, material groove; 2, valve plate; 3, valve seat; 31, steel ring; 32, rubber strip; 33, abutting surface; 34, sealing surface; 341, edge cleaning groove; 4, bracket; 5, valve stem; 51, internally threaded copper sleeve; 52, externally threaded portion; 54, fixing pin; 6, handwheel; 7, medium flow channel; 8, gate cavity. Detailed Embodiments

[0017] To more clearly understand the above-mentioned objects, features, and advantages of the present utility model, the present utility model will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0018] As Figures 1-4 shown, a two-way soft-sealing knife gate valve includes a valve body 1 and a valve plate 2. The valve plate 2 is U-shaped. When the valve is closed, the lower end abuts against the inner ring of a valve seat 3 arranged in a sealing groove 11 provided on the valve body 1. The valve seat 3 is embedded in the inner and outer rings of the sealing groove 11 and abuts against the bottom of the sealing groove 11. The valve seat 3 includes a steel ring 31 and a rubber strip 32 coated on the outer side of the steel ring 31. There are two steel rings 31. The valve seat 3 includes a butting surface 33 protruding relative to the valve plate 2 and a sealing surface 34 opposite to the sealing groove 11. The butting surface 33 is hermetically arranged in fit with the outer ring surface of the valve plate 2. Clearance grooves 341 are provided on both sides of the butting surface 33 relative to the valve plate 2. The butting surface 33 between the two clearance grooves 341 is arranged in fit with the contour of the valve plate 2.

[0019] With the above structural arrangement, the main body of the knife gate valve in this embodiment includes a valve body 1, a valve plate 2, a handwheel 6, a bracket 4, and a valve stem 5. As Figure 2 shown, the upper end of the valve body 1 in this embodiment is open. The valve plate 2 can be driven by the valve stem 5 to be withdrawn from the upper opening. The lifted valve plate 2 releases the medium flow passage 7 on the valve body 1. When the gate valve is opened, the medium flows through the medium flow passage 7. On the contrary, the valve plate 2 moves downward to hermetically abut against the valve seat 3. In this state, the gate valve can form the same seal on both sides of the gate valve. One of the characteristics in this embodiment is that, compared with ordinary rubber sealing abutting members, the valve seat 3 in this embodiment is composed of a U-shaped rubber strip 32 and a steel ring 31 embedded in the rubber strip 32. The steel ring 31 in this embodiment can not only improve the strength of the rubber strip 32, but also serve as a support structure for the valve seat 3 to be installed in the sealing groove 11 of the valve body 1 relative to the valve body 1. As Figure 4 shown, in this embodiment, the surface of the valve plate 2 opposite to the valve seat 3 is relatively simple. Clearance grooves 341 are provided on both sides of the butting surface 33 of the valve seat 3 opposite to the valve plate 2. During the sealing abutting process, the valve plate 2 presses on the butting surface 33 between the two clearance grooves 341. The butting surface 33 subjected to extrusion deformation deforms towards the two clearance grooves 341, reducing the situation that the rubber strip 32 arches towards the medium flow passage 7 under heavy pressure. In addition, it is worth noting that a stop block 111 is provided at the opening of the sealing groove 11 in this embodiment. Refer to Figure 4 , the stop block 111 can catch the valve seat 3, so as to limit the valve seat 3 from being pressed against the top of the U-shaped valve seat 3 by the pressing strip 12 at the upper end when the valve plate 2 withdraws from the gate plate cavity 8, and prevent it from being disengaged from the sealing groove 11 of the valve body 1 relative to the valve body 1.

[0020] Furthermore, two steel rings 31 are provided in this embodiment. The two steel rings 31 are embedded in the rubber strip 32. When the valve plate 2 closes the valve, the valve plate 2 is pushed downward by the valve stem 5 to squeeze the rubber strip 32. Based on the rigid reaction force of the steel ring 31, the strength of the valve seat 3 under force and pressure is improved. Compared with the setting of pure rubber material, it has stronger toughness and longer durability, and is more stable under the working conditions of high pressure difference.

[0021] As a further setting of the above solution, the valve plate 2 and the valve seat 3 are in interference fit for sealing. The valve seat 3 is provided with an open upper end in a U shape. The embedded steel ring 31 is in a U-shaped elastic flare. The rubber strip 32 is coated outside the steel ring 31. The elastic expansion of the steel ring 31 and the bottom of the sealing groove 11 clamp the rubber strip 32 outside the valve seat 3 to maintain installation and sealing.

[0022] As a further setting of the above solution, the valve body 1 is also provided with a pressing strip 12 and a packing 13. The packing 13 is sleeved outside the valve plate 2 in a ring shape and is pressed by the pressing strip 12 in the material groove 14 at the upper end opening of the valve body 1. The pressing strip 12 is fixed relative to the valve body 1 by bolts to close the upper end opening.

[0023] As a further setting of the above solution, the valve body 1 is also provided with a bracket 4 and a valve stem 5. The bracket 4 is provided with a handwheel 6 that is axially fixed and circumferentially rotatable relative to the bracket 4. The handwheel 6 is provided with an inner-threaded copper sleeve 51. The valve stem 5 is provided with an external thread portion 52 and is threadedly matched with the inner-threaded copper sleeve 51. The lower end of the valve stem 5 is fixedly arranged with the valve plate 2 through a fixing pin 54. The handwheel 6 and the inner-threaded copper sleeve 51 are circumferentially fixed. A bearing is arranged between the inner-threaded copper sleeve 51 and the bracket 4 and is axially fixed. When the handwheel 6 is rotated, the inner-threaded copper sleeve 51 is driven to rotate. The rotating inner-threaded copper sleeve 51 is threadedly matched with the valve stem 5 with the external thread portion 52 to rotate, and the valve stem 5 is driven by it to lift and lower. The lower end of the valve stem 5 is fixedly connected with the valve plate 2 through a fixing pin 54. The valve plate 2 is driven to open and close the valve through the handwheel 6.

[0024] As a further setting of the above solution, the valve body 1 is provided with a medium flow channel 7. The inner side of the valve body 1 is also provided with a gate plate cavity 8. The diameter of the medium flow channel 7 is smaller than that of the gate plate cavity 8. The sealing groove 11 is arranged at the edge of the gate plate cavity 8, and a stopper 111 protruding toward the middle is arranged at the opening of the sealing groove 11. It should be noted that when the gate plate cavity 8 opens and closes the valve, due to the small clearance with the valve plate 2, less medium is intercepted. After the valve seat 3 is fitted, the outer side surface of the sealing groove 11 is basically flush with the medium flow channel 7. Therefore, there are basically no deep groove undulations in the medium flow channel 7 on the inner side of the overall valve body 1, so the situation of medium retention is less, the risk of blockage is reduced, the internal medium flows unobstructed, the medium flows smoothly, and the pressure loss is reduced.

[0025] Obviously, those skilled in the art can make various changes and modifications to the present utility model without departing from the spirit and scope of the present utility model. Thus, if these modifications and variations of the present utility model fall within the scope of the present utility model's solution and its equivalent technologies, the present utility model also intends to include these changes and modifications therein.

Claims

1. A two-way soft-sealed knife gate valve, comprising a valve body (1) and a valve plate (2), characterized in that: The valve plate (2) is U-shaped. When the valve is closed, the lower end abuts against the inner ring of the valve seat (3) arranged in the sealing groove (11) provided on the valve body (1). The valve seat (3) is embedded in the inner and outer rings of the sealing groove (11) and abuts against the bottom of the sealing groove (11). The valve seat (3) includes a steel ring (31) and a rubber strip (32) coated on the outer side of the steel ring (31). There are two steel rings (31). The valve seat (3) includes a contact surface (33) protruding relative to the valve plate (2) and a sealing surface (34) opposite to the sealing groove (11). The contact surface (33) is hermetically arranged in fit with the outer ring surface of the valve plate (2).

2. The bi-directional soft-sealing knife gate valve according to claim 1, characterized in that: The valve plate (2) and the valve seat (3) are in interference fit for sealing. The valve seat (3) is arranged with an open upper end in a U shape. The embedded steel ring (31) is in a U-shaped elastic flare. The rubber strip (32) is coated outside the steel ring (31). The steel ring (31) elastically expands to clamp the rubber strip (32) outside the valve seat (3) to maintain installation and sealing with the bottom of the sealing groove (11).

3. The bi-directional soft-sealing knife gate valve according to claim 1, characterized in that: The valve body (1) is further provided with a pressing strip (12) and a packing (13). The packing (13) is sleeved outside the valve plate (2) in a ring shape and is pressed by the pressing strip (12) in the material groove (14) at the upper end opening of the valve body (1). The pressing strip (12) is fixed relative to the valve body (1) by bolts to close the upper end opening.

4. The bi-directional soft-sealing knife gate valve according to claim 1, wherein: The valve body (1) is further provided with a bracket (4) and a valve rod (5). The bracket (4) is provided with a handwheel (6) axially fixed and circumferentially rotatable relative to the bracket (4). The handwheel (6) is provided with an inner-thread copper sleeve (51). The valve rod (5) is provided with an outer-thread portion (52) and is arranged in threaded fit with the inner-thread copper sleeve (51). The lower end of the valve rod (5) is fixed to the valve plate (2) by a fixing pin (54).

5. A two-way soft-sealed knife gate valve according to claim 1, characterized in that: The valve body (1) is provided with a medium flow channel (7). The inner side of the valve body (1) is further provided with a gate cavity (8). The diameter of the medium flow channel (7) is smaller than that of the gate cavity (8). The sealing groove (11) is arranged at the edge of the gate cavity (8), and a stop block (111) protruding towards the middle is arranged at the opening of the sealing groove (11).

6. The bi-directional soft-sealing knife gate valve according to claim 1, characterized in that: Edge cleaning grooves (341) are arranged on both sides of the contact surface (33) relative to the valve plate (2). The contact surface (33) between the two edge cleaning grooves (341) is arranged in fit with the contour of the valve plate (2).

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