One-way sealing knife gate valve

Abstract

The utility model discloses a one-way sealing knife gate valve which comprises a valve body, a gate plate and a valve seat, an annular dovetail groove is formed in the surface, located on one side of the gate plate, of an inner cavity of the valve body, and the valve seat is an annular rubber ring internally provided with a metal framework in an embedded mode. The annular rubber ring comprises a trapezoidal fixing part embedded into the annular dovetail groove and an arc-shaped sealing part exposed out of the annular dovetail groove; a limiting block is arranged on the surface, located on the other side of the flashboard, of the inner cavity of the valve body and close to the lower portion of the flashboard, and an extrusion slope matched with the limiting block is arranged on the periphery of the flashboard. A correction inclined surface is arranged on a sealing surface on one side, matched with the valve seat, of the gate plate, and the width of the correction inclined surface is gradually reduced from the upper part of the valve seat to the lower part; the sealing structure is improved, so that the sealing effect and durability of the knife gate valve are improved.

Description

Technical Field

[0001] This utility model relates to knife gate valves, and more particularly to a one-way sealing knife gate valve. Background Technology

[0002] Valves are typically used in piping systems that require opening, closing, and flow regulation. Among these valves, gate valves are often installed for controlling the transport of highly viscous fluids, powders, and particles. This is because such fluids, due to their compressibility or friction, are not suitable for valve opening and closing actions; therefore, a thin-plate valve disc is used to cut off the fluid and allow it to enter, thereby opening and closing the valve.

[0003] The thin-plate valve disc, also known as a gate, currently seals primarily by installing an annular rubber ring on one side of the valve body. The gate compresses the sealing ring to achieve a seal. However, this annular rubber ring presents several problems: First, the sealing ring is weak and cannot be installed stably, especially during the gate's up-and-down movement to open and close, which can cause deformation and misalignment. Second, to ensure a consistent seal around the entire circumference of the gate and sealing ring, a limiting block is typically installed at the bottom of the other side of the gate. This limiting block compresses the bottom of the gate, causing a slight deformation that tightly engages with the sealing ring. This slight deformation results in a difference in the deformation between the lower and upper sealing rings; the lower sealing ring deforms approximately 0.5mm more than the upper one. Over time, this difference in wear between the upper and lower parts of the sealing ring affects the sealing performance. Summary of the Invention

[0004] The technical problem to be solved by this utility model is to provide a one-way sealing knife gate valve that is stable to install and has a good sealing effect.

[0005] To solve the above-mentioned technical problems, the technical solution of this utility model is: a one-way sealing knife gate valve, comprising a valve body having a channel, a gate plate that can be moved up and down and inserted into the valve body to open and close the channel, and a valve seat that cooperates with the valve body to seal the channel.

[0006] The valve body cavity is provided with an annular dovetail groove on one side surface of the gate. The valve seat is an annular rubber ring with a metal skeleton embedded inside. The annular rubber ring includes a trapezoidal fixing part embedded in the annular dovetail groove and an arc-shaped sealing part exposed outside the annular dovetail groove.

[0007] The valve body cavity is provided with a limiting block on the other side surface of the gate. The limiting block is close to the lower part of the gate. The circumference of the gate is provided with a pressing slope that cooperates with the limiting block.

[0008] The sealing surface on the side of the gate plate that mates with the valve seat is provided with a correction slope, the width of which gradually narrows from the top of the valve seat downwards; when the limiting block and the pressing slope are not engaged, the correction slope is in an inclined state; after the gate plate is fully inserted into the valve body, the limiting block engages and abuts against the pressing slope, the gate plate deforms and the correction slope changes from inclined to vertical, sealing and pressing the gate plate tightly against the valve seat, and the sealing deformation of the arc-shaped sealing part around the circumference of the valve seat is the same.

[0009] As a preferred technical solution, the metal frame is arranged in a ring within the trapezoidal fixing part.

[0010] As a preferred technical solution, the limiting block has two parts corresponding to both sides of the gate.

[0011] As a preferred technical solution, an energy-enhancing packing is installed between the upper part of the gate and the valve body. The energy-enhancing packing consists of PTFE packing, rubber packing, PTFE packing and rubber packing from top to bottom. The PTFE packing in the upper layer is fixed to the valve body by a packing pressure plate and bolts.

[0012] Due to the adoption of the above technical solution, the beneficial effects of this utility model are as follows: By improving the structure of the sealing ring, this utility model not only enhances the strength of the sealing ring, but also ensures the installation stability of the sealing ring by utilizing the dovetail groove, reducing the compression deformation and rolling misalignment of the sealing ring when it moves up and down on the gate, thus improving sealing performance and durability. At the same time, taking advantage of the characteristic of the limit block's slight deformation when the valve plate is closed, a corrective inclined surface is set on the surface of the valve plate to compensate for the slight deformation generated when the gate plate is closed by the limit block. This ensures that after the gate plate is fully closed, the sealing surface in contact with the annular rubber ring adapts to the deformation of the gate plate and is in a completely vertical state, so that the circumference of the arc-shaped sealing part and the gate plate are uniformly sealed. At this time, the upper and lower deformation of the arc-shaped sealing part is consistent, its pressure bearing effect is uniform, and the sealing effect is better. This can reduce the large wear caused by local stress and improve the durability of the sealing ring. Attached Figure Description

[0013] The accompanying drawings are intended only to illustrate and explain the present invention and do not limit the scope of the present invention.

[0014] Figure 1 This is a schematic diagram of the gate in the closed state according to an embodiment of the present invention;

[0015] Figure 2 This is a schematic diagram of the gate portion in the open state according to an embodiment of the present invention;

[0016] Figure 3 yes Figure 2 Enlarged view of point A in the middle;

[0017] Figure 4 This is a structural cross-sectional view of an embodiment of the present invention from a side view angle;

[0018] Figure 5 This is a structural cross-sectional view of an embodiment of the present invention from a frontal view angle;

[0019] Figure 6 yes Figure 5 A partial structural cross-sectional view at point BB;

[0020] Figure 7 This is a state diagram showing the gate not being closed.

[0021] Figure 8 This is a state diagram of the gate in the closed state;

[0022] In the figure: 1-valve body; 2-gate; 3-annular dovetail groove; 4-annular rubber ring; 5-metal skeleton; 6-limiting block; 7-extrusion slope; 8-correction slope; 9-PTFE packing; 10-rubber packing; 11-packing pressure plate. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the following detailed description, only certain exemplary embodiments of the present invention are described by way of illustration. Undoubtedly, those skilled in the art will recognize that various modifications can be made to the described embodiments without departing from the spirit and scope of the present invention. Therefore, the drawings and description are illustrative in nature and not intended to limit the scope of the claims.

[0024] like Figure 1 and Figure 2 As shown, a one-way sealing knife gate valve includes a valve body 1 with a channel, a gate 2 that can be moved up and down and inserted into the valve body 1 to open and close the channel, and a valve seat that cooperates with the valve body 1 to seal the channel. An energy-enhancing packing is installed between the upper part of the gate 2 and the valve body 1, and the upper part of the energy-enhancing packing is fixed to the valve body 1 by a packing pressure plate through bolts.

[0025] See Figure 2 and Figure 3The inner cavity of the valve body 1 is provided with an annular dovetail groove 3 on one side surface of the gate plate 2. The valve seat is an annular rubber ring 4 with a metal skeleton 5 embedded inside. The annular rubber ring 4 includes a trapezoidal fixing part embedded in the annular dovetail groove 3 and an arc-shaped sealing part exposed outside the annular dovetail groove 3. The metal skeleton 5 is arranged in a ring inside the trapezoidal fixing part. The arc-shaped sealing part extends out of the annular dovetail groove 3 at a uniform height. The trapezoidal fixing part and the annular dovetail groove 3 are structurally matched to ensure that the trapezoidal fixing part is completely embedded in the annular dovetail groove 3, improving the installation stability of the annular rubber ring 4. In particular, the annular dovetail groove 3 has a gradually narrowing structure, which can prevent the rubber ring from rolling out of the annular dovetail groove 3 during the up and down movement of the gate plate 2. Furthermore, a metal skeleton 5 is provided in the trapezoidal fixing part. The metal skeleton 5 serves as a support for the rubber ring, which not only improves the structural strength of the rubber ring, but also restricts the annular shape of the rubber ring, ensuring that it is not easily deformed. Since the metal skeleton 5 is located in the middle of the annular dovetail groove 3, the metal skeleton 5 can be stably restricted in the annular dovetail groove 3, ensuring the overall stability of the rubber ring. The arc-shaped sealing part, as a component exposed outside the annular dovetail groove 3 for sealing with the gate plate 2, has a certain degree of flexibility to achieve a good sealing effect.

[0026] See Figures 4 to 6 The valve body 1 has a limiting block 6 on the other side surface of the gate plate 2. The limiting block 6 is close to the lower part of the gate plate 2. The gate plate 2 has a pressing inclined surface 7 that cooperates with the limiting block 6 on its periphery. The limiting block 6 has two wedge-shaped blocks that correspond to the bottom sides of the gate plate 2. The surface of the wedge-shaped block has an inclined surface that cooperates with the pressing inclined surface 7. When the gate plate 2 is pressed down and fully inserted into the valve body 1, the pressing inclined surface 7 slides along the inclined surface of the wedge-shaped block. At this time, the limiting block 6 abuts against the pressing inclined surface 7, forcing the valve plate to seal with the annular rubber ring 4.

[0027] To ensure that the sealing deformation at the upper and lower parts is similar when the annular rubber ring and the valve plate are completely sealed, the surface of the gate plate 2 is designed with a correction slope 8 on the sealing surface of the gate plate 2 that mates with the valve seat. The top of the correction slope 8 is higher than the top of the annular rubber ring 4, and the width of the correction slope 8 gradually narrows from the top of the valve seat downwards. When the gate plate 2 is not closed and the limiting block 6 and the compression slope 7 are not engaged, the bottom end of the gate plate 2 is not restricted by the limiting member, and therefore is not under force. The correction slope 8 is in an inclined state, and it gradually moves away from the annular rubber ring 4 from top to bottom. (See below for further details.) Figure 7The corrective inclined surface 8 has an inclination angle with the vertical plane, causing the distance between the lower arc-shaped sealing ring and the gate plate 2 to be greater than the distance between the upper arc-shaped sealing ring and the gate plate 2. However, after the gate plate 2 is fully inserted into the valve body 1, the pressing inclined surface 7 of the gate plate 2 slides along the inclined surface of the limiting block 6. The limiting block 6 cooperates to abut against the pressing inclined surface 7, which will cause the valve plate to deform slightly towards the annular rubber ring. After the gate plate 2 deforms, the corrective inclined surface 8 changes from inclined to vertical, sealing and pressing the gate plate 2 tightly against the valve seat. See the vertical state. Figure 8 At this point, the sealing deformation of the upper and lower parts of the arc-shaped sealing part is similar, and it can be considered that the sealing deformation of the arc-shaped sealing part around the circumference of the valve seat is the same. The upper and lower deformation of the arc-shaped sealing part is consistent, resulting in uniform pressure bearing and reducing significant wear due to localized stress, thus improving the durability of the sealing ring. The corrective inclined surface 8 is used to compensate for the slight deformation generated when the gate 2 is closed and squeezed by the limiting block 6. This ensures that after the gate 2 is fully closed, the sealing surface of the gate 2 in contact with the annular rubber ring adapts to the deformation of the gate 2 and remains in a completely vertical state, resulting in a uniform seal between the circumference of the arc-shaped sealing part and the gate 2.

[0028] The bottom end of the gate 2 undergoes a slight deformation due to the limiting block 6. Figure 7 The tilt angle is enlarged to show the corrected slope 8, but in reality, this tiny deformation is very small.

[0029] An energy-enhancing packing is installed between the upper part of the gate 2 and the valve body 1. The energy-enhancing packing consists of PTFE packing 9, rubber packing 10, PTFE packing 9, and rubber packing 10 from top to bottom. The upper PTFE packing 9 is fixed to the valve body 1 by bolts through a packing pressure plate 11. The combination of PTFE packing 9, rubber packing 10, and PTFE packing 9 with rubber packing 10 achieves a combination of soft and hard sealing packing, ensuring both sealing performance and packing strength.

[0030] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A one-way sealing gate valve, comprising a valve body having a channel, a gate that can be moved up and down and inserted into the valve body to open and close the channel, and a valve seat that cooperates with the valve body to seal the channel, characterized in that: The valve body cavity is provided with an annular dovetail groove on one side surface of the gate. The valve seat is an annular rubber ring with a metal skeleton embedded inside. The annular rubber ring includes a trapezoidal fixing part embedded in the annular dovetail groove and an arc-shaped sealing part exposed outside the annular dovetail groove. The valve body cavity is provided with a limiting block on the other side surface of the gate. The limiting block is close to the lower part of the gate. The circumference of the gate is provided with a pressing slope that cooperates with the limiting block. The sealing surface on the side of the gate plate that mates with the valve seat is provided with a correction slope, the width of which gradually narrows from the top to the bottom of the valve seat; when the limiting block and the pressing slope are not engaged, the correction slope is in an inclined state; after the gate plate is fully inserted into the valve body, the limiting block engages and abuts against the pressing slope, the gate plate deforms and the correction slope changes from inclined to vertical, sealing and pressing the gate plate tightly against the valve seat, and the sealing deformation of the arc-shaped sealing part around the circumference of the valve seat is the same.

2. The one-way sealing gate valve as described in claim 1, characterized in that: The metal frame is arranged in a ring within the trapezoidal fixing part.

3. The one-way sealing knife gate valve as described in claim 1, characterized in that: The limiting block has two parts, each corresponding to one side of the gate.

4. The one-way sealing knife gate valve as described in claim 1, characterized in that: An energy-enhancing packing is installed between the upper part of the gate and the valve body. The energy-enhancing packing consists of PTFE packing, rubber packing, PTFE packing and rubber packing from top to bottom. The PTFE packing in the upper layer is fixed to the valve body by a packing pressure plate and bolts.

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