CN219327804U

CN219327804U - Super wear-resistant knife gate valve with wear-resistant coating

Info

Publication number: CN219327804U
Application number: CN202320410297.3U
Authority: CN
Inventors: 朱永华; 王英胜; 张海洲
Original assignee: Zhejiang Nuclear Core Valve Technology Co ltd
Current assignee: Zhejiang Nuclear Core Valve Technology Co ltd
Priority date: 2023-03-07
Filing date: 2023-03-07
Publication date: 2023-07-11
Anticipated expiration: 2033-03-07

Abstract

The application relates to a super wear-resistant knife gate valve with a wear-resistant coating, and belongs to the technical field of knife gate valves. Comprising the following steps: the valve body is provided with a medium inlet and a medium outlet which are mutually communicated, a flashboard is arranged in the valve body in a penetrating and sliding manner, and a valve seat which is matched with the flashboard in an opening and closing manner is coaxially and fixedly arranged in the medium outlet; the surface that flashboard and disk seat contacted each other all is coated with compound wear-resisting coating, compound wear-resisting coating is including setting up the transition layer on flashboard and disk seat surface to and set up the wear-resisting functional layer at the transition layer surface. The wear-resistant functional layer on the surface of the transition layer provides good support and interface combination for the surface of the flashboard and the surface of the valve seat, overcomes the mutual abrasion and corrosion of the flashboard and the valve seat, can meet the requirements of mechanical property, corrosion resistance and shock resistance of the flashboard and the valve seat, and effectively improves the reliability and service life of the knife gate valve.

Description

Super wear-resistant knife gate valve with wear-resistant coating

Technical Field

The application relates to the technical field of knife valves, in particular to a super wear-resistant knife gate valve with a wear-resistant coating.

Background

The knife gate valve is also called as knife gate valve, slurry valve and slurry valve, has the advantages of small installation space, uneasy accumulation of sundries, easy cutting of fibers in media and the like, and is widely used in the fields of mining, sewage treatment, papermaking, coal chemical industry, steel, thermal power generation and the like, thereby occupying important roles in national economy.

However, the existing knife gate valve is unreasonable in design, and still has some defects, the existing knife gate valve is poor in wear-resisting effect, the gate plate is easy to be pulled due to the existence of solid particles during opening and closing, the pulled surface of the gate plate carries the solid particles to enter the packing cavity, abrasion of packing can be accelerated, and leakage of the packing sealing position is caused.

Disclosure of Invention

The embodiment of the application provides a super wear-resistant knife gate valve with a wear-resistant coating, which aims to solve the problem that the knife gate valve is poor in wear-resistant effect in the related art.

The embodiment of the application provides a super wear-resisting knife gate with wear-resisting coating, including:

the valve body is provided with a medium inlet and a medium outlet which are mutually communicated, a flashboard is arranged in the valve body in a penetrating and sliding manner, and a valve seat which is matched with the flashboard in an opening and closing manner is coaxially and fixedly arranged in the medium outlet;

the surface that flashboard and disk seat contacted each other all is coated with compound wear-resisting coating, compound wear-resisting coating is including setting up the transition layer on flashboard and disk seat surface to and set up the wear-resisting functional layer at the transition layer surface.

In some embodiments: the valve body comprises an upper valve body and a lower valve body, the upper valve body and the lower valve body are mutually combined to form a cavity for accommodating the flashboard, the medium inlet is positioned on the lower valve body, the medium outlet is positioned on the upper valve body, and the ratio of the length of the flashboard to the inner diameter of the valve seat is greater than two.

In some embodiments: the inner cavity of the lower valve body is provided with an inclined plane, the end part of the flashboard is provided with an arc surface matched with the inclined plane, and when the flashboard and the valve seat are closed, the flashboard slides along the inclined plane so that the flashboard sealing surface of the flashboard is tightly attached to the valve seat sealing end surface of the valve seat.

In some embodiments: the valve seat is provided with a bolt mounting hole, the valve seat is bolted to the medium outlet end of the upper valve body through a third screw, and a first sealing ring is arranged between the valve seat and the upper valve body.

In some embodiments: the thickness of the transition layer is larger than 0.1mm, and the Vickers hardness of the surface of the transition layer is larger than 1000; the thickness of the wear-resistant functional layer is larger than 0.05mm, and the surface Vickers hardness of the wear-resistant functional layer is larger than 3200.

In some embodiments: the transition layer is any one of a supersonic flame spraying tungsten carbide coating, a laser cladding layer, a plasma spraying welding coating and a QPQ heat treatment high-hardness nitriding layer;

the wear-resistant functional layer is any one of a diamond-like carbon layer, a cubic boron nitride layer, a boron carbide layer and a ceramic layer formed by PVD.

In some embodiments: the valve rod is characterized by further comprising a valve rod, one end of the valve rod is connected with the flashboard through a fourth screw, and the other end of the valve rod is connected with an actuator for pushing the flashboard to reciprocate through a bolt.

In some embodiments: the actuator is a cylinder, the valve rod extends into the cylinder and is connected with a piston of the cylinder through a fifth screw, and a second sealing ring is arranged between the valve rod and the piston;

the valve rod penetrates into the lower end cover of the cylinder, and a third sealing ring and a wear-resistant shaft sleeve are arranged between the valve rod and the lower end cover.

In some embodiments: a cylinder supporting plate and a baffle which are connected with the valve body and the cylinder are arranged between the valve body and the cylinder, and the cylinder supporting plate and the baffle form a cavity which is used for coating the valve rod;

one ends of the cylinder supporting plate and the baffle are connected with the valve body through first screws, and the other ends of the cylinder supporting plate and the baffle are connected with the lower end cover through first screws;

the cylinder also comprises an upper end cover, and the upper end cover is connected with the lower end cover through a double-head screw rod;

the upper end cover is sealed with the air cylinder through a fourth sealing ring, the piston is sealed with the air cylinder through a fifth sealing ring, and the lower end cover is sealed with the air cylinder through a sixth sealing ring.

In some embodiments: a packing cavity is formed between the valve body and the flashboard, packing is filled in the packing cavity, a packing pressing sleeve and a packing pressing cover for pressing the packing are arranged at the port of the packing cavity, and a linear spring is arranged between the packing pressing sleeve and the packing pressing cover.

The beneficial effects that technical scheme that this application provided brought include:

the embodiment of the application provides a super wear-resistant knife gate valve with a wear-resistant coating, because the super wear-resistant knife gate valve with the wear-resistant coating is provided with a valve body, a medium inlet and a medium outlet which are mutually communicated are formed in the valve body, a flashboard is arranged in the valve body in a penetrating and sliding manner, and a valve seat which is matched with the flashboard in an opening and closing manner is coaxially and fixedly arranged in the medium outlet; the surfaces of the flashboard and the valve seat, which are in contact with each other, are coated with a composite wear-resistant coating, and the composite wear-resistant coating comprises a transition layer arranged on the surfaces of the flashboard and the valve seat and a wear-resistant functional layer arranged on the surfaces of the transition layer.

Therefore, the surfaces of the flashboard and the valve seat, which are in contact with each other, are all coated with the composite wear-resistant coating, and the composite wear-resistant coating comprises a transition layer arranged on the surfaces of the flashboard and the valve seat and a wear-resistant functional layer arranged on the surfaces of the transition layer. The wear-resistant functional layer on the surface of the transition layer provides good support and interface combination for the surface of the flashboard and the surface of the valve seat, overcomes the mutual abrasion and corrosion of the flashboard and the valve seat, can meet the requirements of mechanical property, corrosion resistance and shock resistance of the flashboard and the valve seat, and effectively improves the reliability and service life of the knife gate valve.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a cross-sectional view of an embodiment of the present application;

FIG. 2 is a top view of a lower valve body according to an embodiment of the present application;

FIG. 3 is a cross-sectional view taken along the line A-A in FIG. 2;

FIG. 4 is a top view of a ram according to an embodiment of the present application;

FIG. 5 is a cross-sectional view taken along the direction B-B in FIG. 4;

FIG. 6 is a top view of a valve seat according to an embodiment of the present application;

fig. 7 is a cross-sectional view taken along the direction C-C in fig. 6.

Reference numerals:

1. a lower valve body; 2. an upper valve body; 3. a flashboard; 4. a valve seat; 5. a valve stem; 6. a cylinder support plate; 7. a baffle; 8. a lower end cap; 9. a piston; 10. a cylinder; 11. an upper end cap; 12. a double-ended screw; 13. wear-resistant shaft sleeve; 14. a packing gland; 15. a filler; 16. a first seal ring; 17. a fourth seal ring; 18. a fifth seal ring; 19. a sixth seal ring; 20. a third seal ring; 21. a first screw; 22. a second screw; 23. a third screw; 24. a fourth screw; 25. a fifth screw; 26. a second seal ring; 27. packing pressing sleeve; 28. a linear spring; 29. a sixth screw; 31. an arc surface; 32. a gate sealing surface; 41. a valve seat sealing end surface; 42. a bolt mounting hole; 101. an inclined plane; 102. a media inlet.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present application based on the embodiments herein.

The embodiment of the application provides a super wear-resistant knife gate valve with a wear-resistant coating, which can solve the problem of poor wear-resistant effect of the knife gate valve in the related art.

Referring to fig. 1 to 7, an embodiment of the present application provides a super wear-resistant knife gate valve with a wear-resistant coating, including:

the medium inlet 102 and the medium outlet which are mutually communicated are formed in the valve body, the flashboard 3 is installed in the valve body in a penetrating and sliding mode, the valve seat 4 which is in opening and closing fit with the flashboard 3 is coaxially and fixedly arranged in the medium outlet, the valve seat 4 is mutually attached to the flashboard 3, and when the valve seat 4 and the flashboard 3 are mutually opened, the valve seat 4 and the medium inlet 102 are mutually communicated to flow a medium. The surfaces of the flashboard 3 and the valve seat 4, which are contacted with each other, are coated with a composite wear-resistant coating, and the composite wear-resistant coating comprises a transition layer arranged on the surfaces of the flashboard 3 and the valve seat 4 and a wear-resistant functional layer arranged on the surfaces of the transition layer.

The flashboard 3 of this application embodiment all is coated with compound wear-resistant coating with the surface of disk seat 4 mutual contact, and compound wear-resistant coating is including setting up the transition layer on flashboard 3 and disk seat 4 surface to and set up the wearing function layer at the transition layer surface. The wear-resistant functional layer on the surface of the transition layer provides good support and interface combination for the surfaces of the flashboard 3 and the valve seat 4, overcomes the mutual wear and corrosion of the flashboard 3 and the valve seat 4, can meet the requirements of mechanical property, corrosion resistance and shock resistance of the flashboard 3 and the valve seat 4, and effectively improves the reliability and service life of the knife gate valve.

In some alternative embodiments: referring to fig. 1, the embodiment of the application provides a super wear-resistant knife gate valve with a wear-resistant coating, wherein a valve body of the super wear-resistant knife gate valve comprises an upper valve body 2 and a lower valve body 1, the upper valve body 2 and the lower valve body 1 are mutually combined to form a cavity for accommodating a flashboard 3, and the peripheries of the upper valve body 2 and the lower valve body 1 are fixedly connected through a plurality of second screws 22. The medium inlet 102 is positioned on the lower valve body 1, the medium outlet is positioned on the upper valve body 2, and the ratio of the length of the flashboard 3 to the inner diameter of the valve seat 4 is more than two.

The valve body of this application embodiment includes upper valve body 2 and lower valve body 1, and upper valve body 2 and lower valve body 1 are involuted each other and are formed the cavity that holds flashboard 3, and flashboard 3 can reciprocate in the cavity that upper valve body 2 and lower valve body 1 formed to open and adjust the area of overflowing between medium entry 102 and the medium export. The upper valve body 2 and the lower valve body 1 are connected with each other through a plurality of second screws 22, so that the valve body is convenient to assemble and maintain. The ratio of the length of the flashboard 3 to the inner diameter of the valve seat 4 is greater than two, so that the contact part of the flashboard 3 and the valve seat 4 and the contact part of the flashboard 3 and the packing 15 are distributed in different areas of the flashboard 3 when the valve is opened and closed, the packing 15 is not affected by the abrasion of the valve seat 4 and the flashboard 3, the reliability of the packing 15 sealing is improved, and the leakage risk of the valve is effectively reduced.

In some alternative embodiments: referring to fig. 2 to 5, the embodiment of the present application provides a super wear-resistant knife gate valve with a wear-resistant coating, wherein an inner cavity of a lower valve body 1 of the super wear-resistant knife gate valve is provided with a bevel 101, an end portion of a gate plate 3 is provided with an arc surface 31 matched with the bevel 101, and when the gate plate 3 and a valve seat 4 are closed, the gate plate 4 slides along the bevel 101 to enable a gate plate sealing surface 32 of the gate plate 3 to be abutted against a valve seat sealing end surface 41 of the valve seat. The valve seat 4 is provided with a bolt mounting hole 42, the valve seat 4 is bolted to the medium outlet end of the upper valve body 2 through a third screw 23, and a first sealing ring 16 is arranged between the valve seat 4 and the upper valve body 2.

The inner cavity of the lower valve body 1 of the embodiment of the application is provided with an inclined plane 101, the inclined plane 101 can be an arc surface or a slope surface, the inclined plane 101 is matched with the arc surface 31 of the flashboard 3, when the flashboard 3 closes the medium inlet 102 and the medium outlet of the valve body, the flashboard 3 slides along the inclined plane 101, so that the flashboard sealing surface 32 of the flashboard 3 is tightly attached to the valve seat sealing end surface 41 of the valve seat 4, and the sealing effect of the flashboard sealing surface 32 and the valve seat sealing end surface 41 is improved.

In some alternative embodiments: referring to fig. 1, an embodiment of the present application provides a super wear-resistant knife gate valve with a wear-resistant coating, wherein the thickness of a transition layer of the super wear-resistant knife gate valve is greater than 0.1mm, and the vickers hardness of the surface of the transition layer is greater than 1000; the thickness of the wear-resistant functional layer is more than 0.05mm, and the surface Vickers hardness of the wear-resistant functional layer is more than 3200. The transition layer is any one of a supersonic flame spraying tungsten carbide coating, a laser cladding layer, a plasma spraying welding coating and a QPQ heat treatment high-hardness nitriding layer; the wear-resistant functional layer is any one of a diamond-like carbon layer, a cubic boron nitride layer, a boron carbide layer and a ceramic layer formed by PVD.

The surface that flashboard 3 and disk seat 4 of this application embodiment contacted each other all is coated with compound wear-resisting coating, and the transition layer adopts any one of supersonic speed flame spraying tungsten carbide coating, laser cladding layer, plasma spray welding coating, QPQ thermal treatment to obtain high hardness nitridization layer, has formed the higher basic unit of hardness, plays fine supporting role to the functional layer, avoids "eggshell effect". The wear-resistant functional layer is any one of a diamond-like carbon layer, a cubic boron nitride layer, a boron carbide layer and a ceramic layer formed by PVD, so that the wear resistance of the flashboard 3 and the valve seat 4 is greatly improved, and the service life of the knife gate valve is also greatly prolonged.

In some alternative embodiments: referring to fig. 1, the embodiment of the application provides a super wear-resistant knife gate valve with a wear-resistant coating, which further comprises a valve rod 5, wherein one end of the valve rod 5 is connected with a gate plate 3 through a fourth screw 24, and the other end of the valve rod 5 is connected with an actuator for pushing the gate plate 3 to reciprocate through a bolt. The actuator is preferably, but not limited to, a cylinder 10, a valve rod 5 extending into the cylinder 10 and connected to a piston 9 of the cylinder 10 by a fifth screw 25, and a second sealing ring 26 is arranged between the valve rod 5 and the piston 9. The valve rod 5 penetrates into the lower end cover 8 of the cylinder 10, and a third sealing ring 20 and a wear-resistant shaft sleeve 13 are arranged between the valve rod 5 and the lower end cover 8.

The valve body and the cylinder 10 are connected, the cylinder supporting plate 6 and the baffle 7 are arranged between the valve body and the cylinder 10, the two cylinder supporting plates 6 and the two baffle 7 are respectively provided with two, the two cylinder supporting plates 6 are parallel to each other and are arranged at intervals, and the two baffle 7 are parallel to each other and are arranged at intervals. The two cylinder support plates 6 and the two baffles 7 together enclose a cavity which encloses the valve rod 5. One end of the cylinder supporting plate 6 and one end of the baffle 7 are connected with the valve body through first screws 21, and the other end of the cylinder supporting plate is connected with the lower end cover 8 through the first screws 21. The cylinder 10 further comprises an upper end cover 11, and the upper end cover 11 and the lower end cover 8 are connected through a plurality of double-headed screws 12. The upper end cover 11 and the cylinder 10 are sealed by a fourth sealing ring 17, the piston 9 and the cylinder 10 are sealed by a fifth sealing ring 18, and the lower end cover 8 and the cylinder 10 are sealed by a sixth sealing ring 19.

In some alternative embodiments: referring to fig. 1, an embodiment of the present application provides a super wear-resistant knife gate valve with a wear-resistant coating, and a packing cavity is formed between a valve body and a gate plate 3 of the super wear-resistant knife gate valve. The packing cavity is filled with packing 15, a packing pressing sleeve 27 for pressing the packing 15 and a packing pressing cover 14 are arranged at the port of the packing cavity, a linear spring 28 is arranged between the packing pressing sleeve 27 and the packing pressing cover 14, and the packing pressing cover 14 is fixed on the valve body through a sixth screw 29. When the packing 15 is worn, the pretightening force of the linear spring 28 can be automatically compensated, so that the effectiveness of the packing 15 is ensured.

Principle of operation

The embodiment of the application provides a super wear-resistant knife gate valve with a wear-resistant coating, because the super wear-resistant knife gate valve with the wear-resistant coating is provided with a valve body, a medium inlet 102 and a medium outlet which are mutually communicated are formed in the valve body, a flashboard 3 is arranged in the valve body in a penetrating and sliding manner, and a valve seat 4 which is in open-close fit with the flashboard 3 is coaxially and fixedly arranged in the medium outlet; the surfaces of the flashboard 3 and the valve seat 4, which are in contact with each other, are coated with a composite wear-resistant coating, and the composite wear-resistant coating comprises a transition layer arranged on the surfaces of the flashboard 3 and the valve seat 4 and a wear-resistant functional layer arranged on the surfaces of the transition layer.

Therefore, the surfaces of the flashboard 3 and the valve seat 4 which are in contact with each other are coated with the composite wear-resistant coating, and the composite wear-resistant coating comprises a transition layer arranged on the surfaces of the flashboard 3 and the valve seat 4 and a wear-resistant functional layer arranged on the surfaces of the transition layer. The wear-resistant functional layer on the surface of the transition layer provides good support and interface combination for the surfaces of the flashboard 3 and the valve seat 4, overcomes the mutual wear and corrosion of the flashboard 3 and the valve seat 4, can meet the requirements of mechanical property, corrosion resistance and shock resistance of the flashboard 3 and the valve seat 4, and effectively improves the reliability and service life of the knife gate valve.

In the description of the present application, it should be noted that the azimuth or positional relationship indicated by the terms "upper", "lower", etc. are based on the azimuth or positional relationship shown in the drawings, and are merely for convenience of description of the present application and simplification of the description, and are not indicative or implying that the apparatus or element in question must have a specific azimuth, be configured and operated in a specific azimuth, and thus should not be construed as limiting the present application. Unless specifically stated or limited otherwise, the terms "mounted," "connected," and "coupled" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

It should be noted that in this application, relational terms such as "first" and "second" and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The foregoing is merely a specific embodiment of the application to enable one skilled in the art to understand or practice the application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A super wear-resistant knife gate valve with wear-resistant coating, comprising:

the valve body is provided with a medium inlet (102) and a medium outlet which are mutually communicated, a flashboard (3) is arranged in the valve body in a penetrating and sliding manner, and a valve seat (4) which is in open-close fit with the flashboard (3) is coaxially and fixedly arranged in the medium outlet;

the surface that flashboard (3) contacted each other with disk seat (4) all is coated with compound wear-resisting coating, compound wear-resisting coating is including setting up the transition layer on flashboard (3) and disk seat (4) surface to and set up the wear-resisting functional layer on the transition layer surface.

2. A wear-resistant coated super wear-resistant knife gate valve as set forth in claim 1, wherein:

the valve body comprises an upper valve body (2) and a lower valve body (1), the upper valve body (2) and the lower valve body (1) are mutually combined to form a cavity for accommodating the flashboard (3), the medium inlet (102) is positioned on the lower valve body (1), the medium outlet is positioned on the upper valve body (2), and the ratio of the length of the flashboard (3) to the inner diameter of the valve seat (4) is larger than two.

3. A wear-resistant coated super wear-resistant knife gate valve as set forth in claim 2, wherein:

the inner cavity of the lower valve body (1) is provided with an inclined plane (101), the end part of the flashboard (3) is provided with an arc surface (31) matched with the inclined plane (101), and when the flashboard (3) and the valve seat (4) are closed, the flashboard (3) slides along the inclined plane (101) so that a flashboard sealing surface (32) of the flashboard (3) is tightly attached to a valve seat sealing end surface (41) of the valve seat (4).

4. A wear-resistant coated super wear-resistant knife gate valve as set forth in claim 2, wherein:

the valve seat (4) is provided with a bolt mounting hole (42), the valve seat (4) is bolted to the medium outlet end of the upper valve body (2) through a third screw (23), and a first sealing ring (16) is arranged between the valve seat (4) and the upper valve body (2).

5. A wear-resistant coated super wear-resistant knife gate valve as set forth in claim 1, wherein:

the thickness of the transition layer is larger than 0.1mm, and the Vickers hardness of the surface of the transition layer is larger than 1000; the thickness of the wear-resistant functional layer is larger than 0.05mm, and the surface Vickers hardness of the wear-resistant functional layer is larger than 3200.

6. A wear-resistant coated super wear-resistant knife gate valve as claimed in claim 1 or 5, wherein:

the transition layer is any one of a supersonic flame spraying tungsten carbide coating, a laser cladding layer, a plasma spraying welding coating and a QPQ heat treatment high-hardness nitriding layer;

7. A wear-resistant coated super wear-resistant knife gate valve as set forth in claim 1, wherein:

the valve rod is characterized by further comprising a valve rod (5), one end of the valve rod (5) is connected with the flashboard (3) through a fourth screw (24), and the other end of the valve rod (5) is connected with an actuator for pushing the flashboard (3) to reciprocate through a bolt.

8. A wear-resistant coated super wear-resistant knife gate valve in accordance with claim 7, wherein:

the actuator is a cylinder (10), the valve rod (5) stretches into the cylinder (10) and is connected with a piston (9) of the cylinder (10) through a fifth screw (25), and a second sealing ring (26) is arranged between the valve rod (5) and the piston (9);

the valve rod (5) penetrates into the lower end cover (8) of the air cylinder (10), and a third sealing ring (20) and a wear-resistant shaft sleeve (13) are arranged between the valve rod (5) and the lower end cover (8).

9. A wear-resistant coated super wear-resistant knife gate valve in accordance with claim 8, wherein:

a cylinder supporting plate (6) and a baffle (7) which are connected with the valve body and the cylinder (10) are arranged between the valve body and the cylinder (10), and the cylinder supporting plate (6) and the baffle (7) form a cavity which is used for coating the valve rod (5);

one end of the cylinder supporting plate (6) and one end of the baffle (7) are connected with the valve body through first screws (21), and the other end of the cylinder supporting plate is connected with the lower end cover (8) through the first screws (21);

the cylinder (10) further comprises an upper end cover (11), and the upper end cover (11) and the lower end cover (8) are connected through a double-head screw rod (12);

the upper end cover (11) is sealed with the cylinder (10) through a fourth sealing ring (17), the piston (9) is sealed with the cylinder (10) through a fifth sealing ring (18), and the lower end cover (8) is sealed with the cylinder (10) through a sixth sealing ring (19).

10. A wear-resistant coated super wear-resistant knife gate valve as set forth in claim 1, wherein:

a packing cavity is formed between the valve body and the flashboard (3), packing (15) is filled in the packing cavity, a packing pressing sleeve (27) for pressing the packing (15) and a packing gland (14) are arranged at the port of the packing cavity, and a linear spring (28) is arranged between the packing pressing sleeve (27) and the packing gland (14).