Disconnecting link plate gate valve without flow guide hole
The combined knife gate and globe valve design addresses pressure and sealing issues by incorporating movable and fixed seat configurations and enhanced sealing mechanisms, ensuring reliable operation and extended valve seat life.
Patent Information
- Application Number
- CN202422479838.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-14
- Publication Date
- 2025-07-15
- Estimated Expiration
- 2034-10-14
AI Technical Summary
Existing knife gate valves and flat gate valves have problems with leakage risks and short service life when fully open, especially in operating conditions containing linear impurities.
Combining the advantages of the knife gate valve and the flat gate valve, a drill gate valve without a flow-through hole is designed. By improving the valve seat assembly structure, the axial translation of the valve seat is limited by using springs and limiting grooves to ensure the sealing effect, and reduce the closing torque in the fully open position. High-temperature resistant material and sealing structure are used to extend the valve seat life.
It achieves good sealing effect and long life of the valve seat in the fully open position, reduces the closing torque, and is suitable for high-temperature environments and operating conditions containing linear impurities.
Smart Images
Figure CN223105310U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of valve equipment, in particular to a knife gate valve without a guide hole. Background Art
[0002] Knife gate valves and flat gate valves are both commonly used valve equipment; the design pressure of knife gate valves is generally low, usually lower than 2.5MPa, and knife gate valves cannot meet the requirements of low leakage; and the disadvantage of flat gate valves is that the valve cannot be in the fully open position for a long time, because when the flat gate valve is in the fully open position, the contact area between the valve seat and the gate is very small, and the valve will be subjected to a large extrusion force during the process from opening to closing, which can easily cause the valve seat to be strained. The valve seat is very easy to deform, causing the valve to leak, and conventional flat gate valves are not suitable for working conditions where the medium contains linear impurities. Linear impurities will cause the flat gate valve to fail to close normally. Utility Model Content
[0003] The technical problem to be solved by the utility model is to provide a knife gate valve without a guide hole which can meet the full opening requirement of the valve and improve the service life of the valve seat.
[0004] In order to solve the above technical problems, the technical solution adopted by the utility model is: a knife gate gate valve without a guide hole, including a valve body, a valve cover and a gate plate, the gate plate is a flat gate plate without a guide hole, the gate plate can be lifted and lowered in the cavity of the valve body through a valve stem, the valve cover is detachably connected to the top of the valve body to form a clearance space adapted to the gate plate, and an inlet end valve seat assembly and an outlet end valve seat assembly are provided in the cavity of the valve body, which can respectively abut against the two side surfaces of the gate plate to form a sealing match, the inlet end valve seat assembly includes an inlet end valve seat, an inlet end pressure ring and a spring, the inlet end pressure ring is detachably connected to the valve body and An annular inlet end limiting groove is formed between the inlet end pressure ring and the valve body, the inlet end valve seat is connected to the valve body through a spring and can be axially translated in the inlet end limiting groove, and the inlet end pressure ring forms an axial limit on the translation path of the inlet end valve seat; the outlet end valve seat assembly includes an outlet end valve seat, an outlet end pressure ring and a valve seat gasket, the outlet end pressure ring is detachably connected to the valve body and forms an annular outlet end limiting groove between the outlet end pressure ring and the valve body, the outlet end valve seat is pressed in the outlet end limiting groove by the outlet end pressure ring, and the valve seat gasket is arranged between the outlet end valve seat and the valve body to form a sealing fit.
[0005] As an improvement of the above scheme: an inlet end locking ring is provided between the inlet end pressure ring and the valve body, the inlet end locking ring is welded to the valve body, and the inlet end pressure ring is detachably connected to the inlet end locking ring by screws; an outlet end locking ring is provided between the outlet end pressure ring and the valve body, the outlet end locking ring is welded to the valve body, and the outlet end pressure ring is detachably connected to the outlet end locking ring by screws.
[0006] As an improvement to the above solution: The axial translation distance of the inlet end valve seat in the inlet end limit groove is 0.3 mm.
[0007] As an improvement to the above solution: The bottom edge of the gate plate is an arc edge, and an inclined surface is provided on the bottom edge of the gate plate. The inclined surface of the gate plate is located on the side of the gate plate facing the inlet end valve seat assembly.
[0008] As an improvement to the above solution: It further includes a bracket detachably connected to the top of the valve cover. The upper end of the valve stem passes through the bracket and extends out of the bracket; a valve packing is provided at the connection between the bracket and the valve cover, and the valve packing abuts against the circumferential surface of the valve stem to form a sealing fit.
[0009] As an improvement to the above solution: The valve packing is a plurality of flexible graphite rings sleeved on the valve stem. A packing groove for accommodating the valve packing is provided at the top of the valve cover. A packing gland is detachably connected to the top of the valve cover. A packing sleeve is provided between the packing gland and the valve packing, and the packing gland presses the valve packing tightly in the packing groove through the packing sleeve.
[0010] As an improvement to the above solution: Anti-slag edges are provided on both the inlet end valve seat and the outlet end valve seat. The anti-slag edges extend axially and are in contact with the inner surface of the cavity of the valve body. The anti-slag edges shield the joints between the outlet end valve seat and the inlet end valve seat and the valve body.
[0011] As an improvement to the above solution: It further includes two guide ribs fixed on the inner wall of the valve body. The two guide ribs are vertically arranged and symmetrically distributed on both sides of the gate plate. Guide grooves adapted to the guide ribs and forming a sliding fit are provided on the gate plate.
[0012] As an improvement to the above solution: A cleaning manifold is further provided outside the valve body. The cleaning manifold is communicated with the cavity of the valve body through a plurality of flush ports evenly arranged on the valve body; a flush connection port controlled by a needle valve is also provided on the cleaning manifold.
[0013] As an improvement to the above solution: A reverse seal structure is provided at the connection between the valve stem and the gate plate. The reverse seal structure is a convex ring integrally formed with the valve stem. The end face of the convex ring facing the valve cover is a conical surface; a strengthening layer is surfacing welded at the position of the valve cover that cooperates with the reverse seal structure.
[0014] The beneficial effects of the present utility model are as follows: The present utility model combines a knife gate valve and a flat gate valve, integrating the advantages of both and simultaneously solving their disadvantages. By improving the valve seat assemblies at the inlet and outlet ends of the valve, in the inlet end valve seat assembly, a spring is used to connect the inlet end valve seat to the valve body in the valve seat hole of the valve body. The inlet end valve seat can perform axial translation. At the same time, an inlet end limiting groove is formed between the inlet end pressing ring and the valve body to limit the translation of the inlet end valve seat, so that even when the gate plate is in the fully open position, the inlet end valve seat can only translate within a limited range, effectively reducing the torque when the valve is closed. When the gate plate is in the fully closed position, the inlet end valve seat is pressed against the gate plate by the elastic force of the spring, and the upstream medium provides pressure at the inlet end to push the gate plate tightly against the sealing surface of the outlet end valve seat, achieving a good one-way sealing effect. In the outlet end valve seat assembly of the present utility model, the outlet end valve seat is pressed tightly on the valve body by the outlet end pressing ring, so that the outlet end valve seat cannot move axially within the valve body. At the same time, a valve seat gasket is provided to ensure the sealing fit between the outlet end valve seat and the valve body. In the present utility model, the gate plate can be in the fully open position for a long time to meet the flow requirements of the medium in the valve. At the same time, by optimizing the structure of the valve seat assembly, the working environment of the valve seat is improved, making the sealing effect of the valve seat more reliable and extending the service life of the valve seat. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 is a front cross-sectional view of the present utility model;
[0016] Figure 2 is a side cross-sectional view of the present utility model;
[0017] Figure 3 is Figure 2 an enlarged schematic view of part A in
[0018] Figure 4 is Figure 2 an enlarged schematic view of part B in
[0019] In the figure, the markings are: 100 - valve body, 110 - guiding rib, 200 - valve cover, 300 - gate plate, 400 - valve stem, 410 - inverted sealing structure, 500 - inlet end valve seat assembly, 510 - inlet end valve seat, 520 - inlet end pressing ring, 530 - spring, 540 - inlet end locking ring, 600 - outlet end valve seat assembly, 610 - outlet end valve seat, 620 - outlet end pressing ring, 630 - valve seat gasket, 640 - outlet end locking ring, 700 - support, 710 - valve packing, 720 - packing gland, 730 - packing sleeve, 800 - slag-proof edge, 900 - cleaning manifold. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0020] For the convenience of understanding the present utility model, the present utility model will be further described below in conjunction with the accompanying drawings.
[0021] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "front", "rear", "left", "right", "upper", "lower", "inner", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of description and does not indicate or imply that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.
[0022] As Figure 1 and Figure 2 shown, the non-flow-guide-hole knife gate valve disclosed in the present utility model includes a valve body 100, a valve cover 200, a gate plate 300, a valve stem 400, an inlet end valve seat assembly 500, and an outlet end valve seat assembly 600. A cavity is provided inside the valve body 100 as a valve cavity. The two sides of the valve body 100 are respectively an inlet end flow channel and an outlet end flow channel communicating with the cavity. The medium enters the cavity of the valve body 100 through the inlet end flow channel and then is discharged through the outlet end flow channel. The gate plate 300 is used to open and close the valve body 100. The top end of the gate plate 300 is connected to the valve stem 400. The gate plate 300 can be controlled to vertically lift and lower in the cavity of the valve body 100 through the valve stem 400. When the gate plate 300 descends, the flow of the medium in the cavity is cut off and the valve is closed. When the gate plate 300 ascends, the medium in the cavity resumes flowing and the valve is opened. The valve cover 200 is detachably connected to the top of the valve body 100, and the space inside the valve cover 200 provides a corresponding space for the ascending movement of the gate plate 300. In the present utility model, the inlet end valve seat assembly 500 and the outlet end valve seat assembly 600 respectively abut against the two side surfaces of the gate plate 300, so that both the inlet end valve seat assembly 500 and the outlet end valve seat assembly 600 can form a sealing fit with the gate plate 300, providing a sealing effect when the gate plate 300 descends to close the valve and preventing the medium from leaking when the valve is closed.
[0023] In order to meet the working requirements of the valve in a high-temperature environment, in the present utility model, both the valve body 100 and the valve cover 200 are made of heat-resistant chrome molybdenum steel material, and the rest of the internal structure is made of austenitic stainless steel. Each sealing surface is sprayed with hard alloy by supersonic spraying process.
[0024] Specifically, as Figure 2 and Figure 3As shown in the figure, the inlet end valve seat assembly 500 adopted in the present utility model includes an inlet end valve seat 510, an inlet end pressing ring 520 and a spring 530. Both the inlet end valve seat 510 and the inlet end pressing ring 520 are annular structures coaxially arranged with the flow channel of the valve body 100. The inlet end valve seat 510 is a component that directly contacts the gate plate 300 to form a sealing fit. The inlet end pressing ring 520 is detachably connected to the valve body 100, and an annular inlet end limiting groove is formed between the inlet end pressing ring 520 and the valve body 100. The inlet end valve seat 510 is connected to the valve body 100 through the spring 530. The inlet end valve seat 510 is arranged in the inlet end limiting groove. The extending direction of the spring 530 is parallel to the axial direction of the flow channel of the valve body 100. The inlet end valve seat 510 can axially translate towards the gate plate 300 under the elastic force of the spring 530. When the gate plate 300 descends to close the valve, the inlet end valve seat 510 is pressed against the side surface of the gate plate 300 under the elastic force of the spring 530 to achieve a sealing fit with the gate plate 300. Since the inlet end valve seat 510 is arranged in the inlet end limiting groove, the inlet end limiting groove plays a role in limiting the axial translation of the inlet end valve seat 510. By controlling the width of the inlet end limiting groove, the axial translation distance of the inlet end valve seat 510 can be determined. In the present utility model, in order to ensure that the valve can be normally closed and the closing torque is small, the axial translation distance of the inlet end valve seat 510 in the inlet end limiting groove is set to 0.3 mm. That is, when the gate plate 300 descends to close the valve, the axial translation distance of the inlet end valve seat 510 towards the direction away from the gate plate 300 under the extrusion and push of the gate plate 300 is 0.3 mm. It can also be understood that when the gate plate 300 ascends to open the valve, the inlet end valve seat 510 is separated from the gate plate 300 and will be blocked by the inlet end pressing ring 520 and cannot continue to translate after axially translating 0.3 mm under the elastic force of the spring 530. Since during the process of the gate plate 300 descending to close the valve, the gate plate 300 needs to extrude the inlet end valve seat 510 to make it translate towards the direction away from the gate plate 300, and under the limitation of the above axial translation distance, due to the limiting effect of the inlet end pressing ring 520 on the inlet end valve seat 510, the spring 530 will not be fully extended, and the inlet end pressing ring 520 can bear a part of the pressure of the spring 530, the extrusion force received by the inlet end valve seat 510 from the gate plate 300 is reduced, so that the closing torque of the valve can be effectively reduced, the process of the gate plate 300 descending, that is, the closing process of the valve, is smoother, and the inlet end valve seat 510 is not easily damaged, thereby effectively improving the service life of the inlet end valve seat 510.
[0025] Furthermore, in the present utility model, the bottom edge of the gate plate 300 is set as an arc edge, and an inclined surface is provided on the bottom edge of the gate plate 300 so that the bottom cross-section of the gate plate 300 forms a knife-edge shape. The inclined surface of the gate plate 300 is located on the side of the gate plate 300 facing the inlet-end valve seat assembly 500. Through the above improvement of the gate plate 300, the linear impurities in the medium can be cut off when the gate plate 300 descends to close the valve, ensuring the normal closing of the valve. At the same time, when the gate plate 300 descends and contacts the inlet-end valve seat 510, the inlet-end valve seat 510 can be smoothly pushed.
[0026] Specifically, as Figure 2 and Figure 4 shown, the outlet-end valve seat assembly 600 adopted in the present utility model includes an outlet-end valve seat 610, an outlet-end pressing ring 620, and a valve seat gasket 630. Both the outlet-end valve seat 610 and the outlet-end pressing ring 620 are annular structures coaxially arranged with the flow channel of the valve body 100. The outlet-end valve seat 610 is a component directly in contact with the gate plate 300 to form a sealing fit. Different from the structural feature that the inlet-end valve seat 510 in the inlet-end valve seat assembly 500 can axially translate, the outlet-end valve seat 610 in the outlet-end valve seat assembly 600 is a fixed structure. The outlet-end pressing ring 620 is detachably connected to the valve body 100 and forms an annular outlet-end limiting groove between the outlet-end pressing ring 620 and the valve body 100. The outlet-end valve seat 610 is arranged in the outlet-end limiting groove, and the outlet-end pressing ring 620 presses the outlet-end valve seat 610 in the outlet-end limiting groove so that the outlet-end valve seat 610 cannot axially move, and the outlet-end valve seat 610 is closely attached to the valve body 100. A sealing groove is provided on the surface of the outlet-end valve seat 610 in contact with the valve body 100, and the valve seat gasket 630 is installed in the sealing groove and is pressed between the outlet-end valve seat 610 and the valve body 100, so as to form a good sealing fit between the outlet-end valve seat 610 and the valve body 100. When the gate plate 300 descends to close the valve, the gate plate 300 is closely attached to the sealing surface of the outlet-end valve seat 610 under the thrust of the upstream medium in the inlet-end flow channel, achieving a good sealing effect.
[0027] Furthermore, as Figure 3 and Figure 4 shown, in the present utility model, an inlet-end locking ring 540 and an outlet-end locking ring 640 are provided to achieve the detachable connection between the inlet-end pressing ring 520 and the valve body 100 and the detachable connection between the outlet-end pressing ring 620 and the valve body. The inlet-end locking ring 540 is welded to the valve body 100, and the inlet-end pressing ring 520 is detachably connected to the inlet-end locking ring 540 by screws; the outlet-end locking ring 640 is welded to the valve body 100, and the outlet-end pressing ring 620 is detachably connected to the outlet-end locking ring 640 by screws.
[0028] Furthermore, in order to improve the sealing effect of the mating surface between the valve seat assembly and the valve body 100, asFigure 3 and Figure 4 As shown in Figure 4 , on both the inlet end valve seat 510 and the outlet end valve seat 610 of the present utility model, slag-proof rib 800 is provided. The slag-proof rib 800 axially extends in a direction away from the gate plate 300 and abuts against the inner surface of the cavity of the valve body 100. The slag-proof rib 800 shields the joints between the inlet end valve seat 510 and the outlet end valve seat 610 and the valve body 100, so as to prevent the medium or impurities from entering between the sealing surfaces of the valve seat and the valve body 100.
[0029] As Figure 1 and Figure 2 As shown in Figure 2 , a bracket 700 is provided on the top of the valve cover 200 of the present utility model. The bracket 700 is detachably connected to the top of the valve cover 200. A channel for the valve stem 400 to move up and down is provided in the bracket 700. The upper end of the valve stem 400 extends upward through the bracket 700 and out of the bracket 700, and the lower end of the valve stem 400 extends downward through the bracket 700 and into the valve cover 200 and is connected to the gate plate 300. A valve packing 710 is provided at the connection between the bracket 700 and the valve cover 200. The valve packing 710 is in sealing contact with the circumferential surface of the valve stem 400 to form a sealing fit. The valve packing 710 adopts a plurality of flexible graphite rings sleeved on the valve stem 400. A packing groove for accommodating the valve packing 710 is provided at the top of the valve cover 200. A packing gland 720 is detachably connected to the top of the valve cover 200 by screws. A packing sleeve 730 is provided between the packing gland 720 and the valve packing 710. The packing gland 720 presses the valve packing 710 tightly in the packing groove through the packing sleeve 730.
[0030] Furthermore, the present utility model adds a reverse sealing function to the valve. As Figure 1 and Figure 2 shown, a reverse sealing structure 410 is provided at the connection between the valve stem 400 and the gate plate 300. The reverse sealing structure 410 is a convex ring integrated with the valve stem 400. The end face of the convex ring facing the valve cover 200 is a conical surface. When the gate plate 300 is lifted by the valve stem 400 and the reverse sealing structure 410 rises to the top of the valve cover 200, the conical surface of the reverse sealing structure 410 can be embedded into the through hole for the valve stem 400 to pass through at the top of the valve cover 200, so that the conical surface of the reverse sealing structure 410 forms an interference fit with the orifice of the through hole, providing a good sealing effect. At the same time, in order to prevent the orifice of the through hole from being worn due to the collision and extrusion of the reverse sealing structure 410, the present utility model also surfacing welds austenitic stainless steel at the position of the valve cover 200 that cooperates with the reverse sealing structure 410 to form a reinforcing layer that protects the orifice of the through hole.
[0031] As Figure 1As shown in the figure, two guiding ribs 110 are provided on the inner wall of the valve body 100 of the present utility model. The two guiding ribs 110 are vertically arranged and symmetrically distributed on both sides of the gate plate 300. At the same time, guiding grooves adapted to the two guiding ribs 110 are provided on the gate plate 300. The two guiding ribs 110 are respectively inserted into the corresponding guiding grooves and form a sliding fit with the guiding grooves. The guiding ribs 110 slide along the corresponding guiding grooves to limit and guide the lifting movement of the gate plate 300, so that the lifting path of the gate plate 300 during the opening and closing of the valve always remains on the center line of the valve body 100.
[0032] As Figure 1 As shown in the figure, a cleaning manifold 900 is provided outside the valve body 100 of the present utility model, and a plurality of flushing ports are provided at the bottom of the valve body 100. The flushing ports are evenly distributed along the outer circle of the valve seat. The flushing ports are communicated with the cavity of the valve body 100. The plurality of flushing ports are connected in series through the cleaning manifold 900, and a flushing connection port is installed on the cleaning manifold 900. The flushing connection port is configured with a needle valve, and the opening and closing of the flushing connection port is controlled by the needle valve; when performing the flushing operation, the needle valve is opened, and cleaning liquid is introduced into the cleaning manifold 900 through the flushing connection port, and then transported to each flushing port through the cleaning manifold 900 for flushing the inside of the valve body 100.
Claims
1. Non-conductive orifice knife gate valve, comprising a valve body (100), a valve cover (200) and a gate plate (300). The gate plate (300) is a flat gate plate without a conductive orifice. The gate plate (300) is vertically arranged in the cavity of the valve body (100) through a valve stem (400). The valve cover (200) is detachably connected to the top of the valve body (100) to form a clearance space adapted to the gate plate (300). An inlet end valve seat assembly (500) and an outlet end valve seat assembly (600) are arranged in the cavity of the valve body (100), which can respectively abut against both side surfaces of the gate plate (300) to form a sealing fit. It is characterized in that: The inlet valve seat assembly (500) includes an inlet valve seat (510), an inlet gland (520), and a spring (530). The inlet gland (520) is detachably connected to the valve body (100) and forms an annular inlet limiting groove between the inlet gland (520) and the valve body (100). The inlet valve seat (510) is connected to the valve body (100) through the spring (530) and is axially translatable and disposed in the inlet limiting groove. The inlet gland (520) forms an axial limit on the translation path of the inlet valve seat (510). The outlet valve seat assembly (600) includes an outlet valve seat (610), an outlet gland (620), and a valve seat gasket (630). The outlet gland (620) is detachably connected to the valve body (100) and forms an annular outlet limiting groove between the outlet gland (620) and the valve body (100). The outlet valve seat (610) is pressed by the outlet gland (620) in the outlet limiting groove, and the valve seat gasket (630) is disposed between the outlet valve seat (610) and the valve body (100) to form a sealing fit.
2. The non-flow-guide orifice knife gate valve according to claim 1, characterized in that: An inlet locking ring (540) is provided between the inlet gland (520) and the valve body (100). The inlet locking ring (540) is welded to the valve body (100), and the inlet gland (520) is detachably connected to the inlet locking ring (540) by screws. An outlet locking ring (640) is provided between the outlet gland (620) and the valve body (100). The outlet locking ring (640) is welded to the valve body (100), and the outlet gland (620) is detachably connected to the outlet locking ring (640) by screws.
3. The non-guide-hole knife gate valve according to claim 1, characterized in that: The axial translation distance of the inlet valve seat (510) in the inlet limiting groove is 0.3 mm.
4. The non-guide-hole knife gate valve according to claim 1, characterized in that: The bottom edge of the gate plate (300) is an arc edge, and a bevel is provided on the bottom edge of the gate plate (300). The bevel of the gate plate (300) is located on the side of the gate plate (300) facing the inlet valve seat assembly (500).
5. The non-guide-hole knife gate valve according to claim 1, characterized in that: It further includes a bracket (700) detachably connected to the top of the valve cover (200). The upper end of the valve stem (400) passes through the bracket (700) and extends outside the bracket (700). A valve packing (710) is provided at the connection between the bracket (700) and the valve cover (200). The valve packing (710) abuts against the circumferential surface of the valve stem (400) to form a sealing fit.
6. The non-guide-hole knife gate valve according to claim 5, characterized in that: The valve packing (710) is a plurality of flexible graphite rings sleeved on the valve stem (400). A packing groove for accommodating the valve packing (710) is provided at the top of the valve cover (200). A packing gland (720) is detachably connected to the top of the valve cover (200). A packing sleeve (730) is provided between the packing gland (720) and the valve packing (710). The packing gland (720) presses the valve packing (710) in the packing groove through the packing sleeve (730).
7. The non-guide-hole knife gate valve according to claim 1, characterized in that: The inlet end valve seat (510) and the outlet end valve seat (610) are both provided with slag-proof ribs (800). The slag-proof ribs (800) extend axially and are in contact with the inner surface of the cavity of the valve body (100). The slag-proof ribs (800) cover the joints of the outlet end valve seat (610) and the inlet end valve seat (510) with the valve body (100).
8. The non-guide-hole knife gate valve according to claim 1, wherein: It further includes two guide ribs (110) fixed on the inner wall of the valve body (100). The two guide ribs (110) are vertically arranged and symmetrically distributed on both sides of the gate plate (300). Guide grooves adapted to the guide ribs (110) and forming a sliding fit are provided on the gate plate (300).
9. The non-flow-guide orifice knife gate valve according to claim 1, wherein: A cleaning manifold (900) is further provided outside the valve body (100). The cleaning manifold (900) is communicated with the cavity of the valve body (100) through a plurality of flush ports evenly arranged on the valve body (100); a flush connection port controlled to open and close by a needle valve is further provided on the cleaning manifold (900).
10. The non-flow-guiding orifice knife gate valve according to claim 1, wherein: A reverse seal structure (410) is provided at the connection between the valve stem (400) and the gate plate (300). The reverse seal structure (410) is a convex ring integrally formed with the valve stem (400), and the end face of the convex ring facing the valve cover (200) is a conical surface; a strengthening layer is built-up welded at the position on the valve cover (200) that cooperates with the reverse seal structure (410).