Sealing device for pull rod of medium-speed coal mill

Abstract

The utility model belongs to the technical field of sealing devices for medium-speed mills, and provides a sealing device for a pull rod of a medium-speed coal mill, which is characterized in that an upper sealing structure mainly comprises a sleeve, a sealing sleeve, an upper sealing rubber part, a gland and a cover plate; the sleeve is provided with a sealing sleeve through a cover plate; an upper sealing rubber part is arranged in the sealing sleeve; a positioning step is arranged at the upper part of the outer side wall of the upper sealing rubber part, and a mounting ring is arranged at the lower part of the outer side wall of the upper sealing rubber part; the mounting ring is arranged in the mounting groove; a gland is arranged on the positioning step and is fixedly connected with the end face of the sealing sleeve; the lower sealing structure mainly comprises a cover body, a lower sealing rubber part and a lower end cover; the lower sealing rubber part is of an integrally-formed structure and is installed in a cavity formed by the cover body and the lower end cover. Even if the pull rod moves up and down and left and right, zero abrasion of the pull rod can be guaranteed, and the service life of the pull rod is long.

Description

Technical Field

[0001] The utility model belongs to the technical field of medium-speed mill sealing devices, in particular to a tie rod sealing device for a medium-speed coal mill. Background Art

[0002] The existing roller-disc medium-speed coal mill uses a double seal form of sealing air and metal seal for the tie rod seal. During operation, due to the driving effect of the loading force and the grinding force of the grinding roller, the tie rod slides continuously in the horizontal and vertical directions, resulting in double wear of the joint bearing 30 and the wear-resistant bushing 31. Long-term wear will increase the gap between the joint bearing and the wear-resistant bushing, and the sealing air will leak out. When the air leakage is serious, the sealing air pressure in the tie rod seal body is reduced, and the primary air enters the seal body and carries coal powder. Small particles of coal powder are blown out of the mill shell, and large particles of coal powder are stuck in the gap between the joint bearing and the wear-resistant bushing, which accelerates the wear of both.

[0003] CN204025693U discloses a sealing device for a tie rod of a medium-speed coal mill, comprising an upper sealing upper body, an upper sealing lower body and an upper sealing upper cover. The upper sealing upper body and the upper sealing lower body form an upper seal, and the upper seal is made of alloy. The tie rod moves up and down, left and right, which still causes certain wear to the tie rod, and the service life of the tie rod is relatively short. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a tie rod sealing device for a medium-speed coal mill, which can ensure zero wear on the tie rod, a long service life of the tie rod, and prevent coal powder particles from entering the sealing body even if the tie rod moves up and down or left and right.

[0005] In order to solve the above technical problems, the utility model provides a medium-speed coal mill tie rod sealing device, including an upper sealing structure and a lower sealing structure, the upper sealing structure is mainly composed of a casing, a sealing sleeve, an upper sealing rubber part, a pressure cover, and a cover plate; the casing is installed with the sealing sleeve through the cover plate, and the upper sealing rubber part is installed in the sealing sleeve; an installation groove is provided on the inner wall of the sealing sleeve; an air cavity is provided on the wall of the upper sealing rubber part; a positioning step is provided on the upper part of the outer wall of the upper sealing rubber part, and a mounting ring is provided on the lower part; the mounting ring is provided in the mounting groove; a pressure cover is provided on the positioning step, and the pressure cover is fixedly connected to the end face of the sealing sleeve; the lower sealing structure is mainly composed of a cover body, a lower sealing rubber part, and a lower end cover; the lower sealing rubber part is an integrally formed structure, and is installed in a cavity formed by the cover body and the lower end cover.

[0006] Preferably, the upper sealing rubber member is made of silicone rubber, and a plurality of ventilation ring grooves I are evenly arranged on the inner side wall, and except for the bottom ventilation ring groove I, the other ventilation ring grooves I are connected to the air cavity.

[0007] Preferably, the cross section of the cover plate is right-angled, one end of which is inserted into the positioning groove of the outer side wall of the sealing sleeve, and the other end is fixedly arranged on the connecting plate of the sleeve.

[0008] Preferably, an annular gap is provided between the sealing sleeve and the cover plate.

[0009] Preferably, the sealing sleeve is made of ductile iron, and the gap between the sealing sleeve and the cover plate at the joint surface is no greater than 0.05 mm.

[0010] Preferably, the lower sealing rubber component is made of silicone rubber, a plurality of ventilation ring grooves II are provided on the inner wall, a fastening groove is provided on the outer wall, and a throat clamp is provided in the fastening groove.

[0011] Preferably, the lower sealing rubber member has wings, which extend outwards so that there are gaps between the top surface, bottom surface, side surfaces of the lower sealing rubber member and the top surface, bottom surface and inner wall of the cavity.

[0012] Preferably, a mounting block is provided on the cover body, and the mounting block is fixedly connected to the lower end cover.

[0013] Compared with the prior art, the beneficial effects of the present invention are:

[0014] 1. The tie rod seal of the utility model adopts a double sealing form of sealing air and rubber sealing. The upper sealing rubber part is fixed in the sealing sleeve by a positioning step and a mounting ring. Even if the tie rod moves up and down or left and right, it can ensure zero wear on the tie rod. The tie rod has a long service life, and the rubber itself has a certain elasticity. Therefore, the gap at the tie rod can be guaranteed to be extremely small for a long time, so that large coal powder particles cannot enter the sealing body, and small coal powder particles cannot enter the sealing body due to the effect of sealing air, thereby preventing the leakage of coal powder at this location.

[0015] 2. The sealing sleeve of the utility model is made of ductile iron, which has certain elasticity and good wear resistance, is conducive to the stable installation of the upper sealing structure, is convenient for positioning the pull rod, and can also avoid wear of the pull rod.

[0016] 3. The utility model provides a fastening groove on the outer side wall of the lower sealing rubber member, in which a throat clamp is arranged, and the lower sealing rubber member is fastened to the pull rod by the throat clamp to ensure the sealing effect between the pull rod and the coal mill loading frame. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the background technology diagram of the utility model;

[0018] Figure 2 It is an overall schematic diagram of the utility model;

[0019] Figure 3 It is the upper sealing structure of the utility model;

[0020] Figure 4 For this utility model Figure 1 Enlarged view of point A in the middle;

[0021] Figure 5It is the lower sealing structure of the utility model;

[0022] Figure 6 For this utility model Figure 1 Enlarged view of point B in the middle.

[0023] Figure number: 1. Upper sealing structure, 2. Lower sealing structure, 3. Cover body, 4. Sealing sleeve, 5. Lower sealing rubber part, 6. Upper sealing rubber part, 7. Pressure cover, 8. Cover plate, 9. Lower end cover, 10. Sealing chamber, 11. Sleeve, 12. Ventilation ring groove I, 13. Positioning groove, 14. Annular gap, 15. Connecting plate, 16. Mounting groove, 17. Positioning step, 18. Mounting ring, 19. Ventilation ring groove II, 20. Fastening groove, 21. Throat clamp, 22. Wing, 23. Mounting block, 24. Wind chamber. DETAILED DESCRIPTION

[0024] like Figure 2 As shown, the tie rod seal of the medium-speed coal mill includes an upper sealing structure 1 and a lower sealing structure 2. The upper sealing structure 1 is mainly composed of a sleeve 11, a sealing sleeve 4, an upper sealing rubber member 6, a gland 7, and a cover plate 8; the sleeve 11 is installed with the sealing sleeve 4 through the cover plate 8, the upper sealing rubber member 6 is installed in the sealing sleeve 4, and the wall of the upper sealing rubber member 6 is provided with an air cavity 24. The inner wall of the sealing sleeve 4 is provided with a mounting groove 16, the upper part of the outer wall of the upper sealing rubber member 6 is provided with a positioning step 17, and the lower part is provided with a mounting ring 18. The mounting ring 18 is arranged in the mounting groove 16; the gland 7 is arranged on the positioning step 17, and the gland 7 is fixedly connected to the end face of the sealing sleeve 4. The lower sealing structure 2 is mainly composed of a cover body 3, a lower sealing rubber member 5, and a lower end cover 9; the lower sealing rubber member 5 is an integrally formed structure, and is installed in the cavity formed by the cover body 3 and the lower end cover 9. The tie rod seal of the present application adopts the form of combining sealing air and rubber sealing. The upper sealing rubber part 6 is fixed in the sealing sleeve 4 by the positioning step 17 and the mounting ring 18. Even if the tie rod moves up and down or left and right, it can ensure zero wear on the tie rod. The service life of the tie rod is relatively long, and the rubber itself has a certain elasticity. Therefore, the gap at the tie rod can be guaranteed to be extremely small for a long time, so that large coal powder particles cannot enter the sealing body, and small coal powder particles cannot enter the sealing body due to the action of sealing air, thereby preventing the leakage of coal powder at this point.

[0025] The upper sealing rubber component 6 is made of silicone rubber, which has excellent high temperature resistance (250-300℃) and low temperature resistance (-40-60℃), is easy to install and replace, has excellent resilience and small permanent deformation, has strong anti-aging properties, and has a service life of more than 8000h. The inner wall of the upper sealing rubber component 6 is evenly provided with a plurality of ventilation ring grooves Ⅰ12. Except for the bottom ventilation ring groove Ⅰ12, the other ventilation ring grooves Ⅰ12 are connected to the wind cavity 24. Compressed air is filled into the sealing cavity 10, passing through the inlet at the bottom of the wind cavity 24, the wind cavity 24, the ventilation ring groove Ⅰ12, the gap between the upper sealing rubber component 6 and the pull rod, and finally to the outside of the upper sealing structure 1, such as Figure 4 The arrow indicates the direction of the sealing wind. The inner wall of the upper sealing rubber member 6 below the ventilation ring groove Ⅰ12 is evenly provided with serrations, so that the upper sealing rubber member 6 can firmly grasp the pull rod.

[0026] like Figure 3 As shown, the cross section of the cover plate 8 is right-angled, one end of which is inserted into the positioning groove 13 of the outer wall of the sealing sleeve 4, and the other end is fixedly arranged on the connecting plate 15 of the sleeve 11, which simplifies the structure of the cover plate 8 and facilitates assembly.

[0027] like Figure 4 As shown, an annular gap 14 is provided between the sealing sleeve 4 and the cover plate 8 to ensure that the pull rod can float forward, backward, up, down, left and right within a certain range and can be reliably sealed when working.

[0028] The sealing sleeve 4 is made of QT400-15 ductile iron, which has certain elasticity and good wear resistance, which is conducive to the stable installation of the upper sealing structure 1, convenient for positioning the tie rod, and can also avoid tie rod wear. The gap between the sealing sleeve 4 and the cover plate 8 is no more than 0.05mm, ensuring the sealing effect of the upper sealing structure 1 after installation.

[0029] like Figure 5 As shown, the lower sealing rubber component 5 is made of silicone rubber, which has excellent high temperature resistance (250-300°C) and low temperature resistance (-40-60°C), is easy to install and replace, has excellent resilience and small permanent deformation, has strong anti-aging properties, and has a service life of more than 8000 hours. Both the upper and lower sealing rubber components are made of silicone rubber, which is inexpensive, easy to replace, has a long service life, and reduces production costs. A plurality of ventilation ring grooves Ⅱ19 are evenly arranged on the inner wall of the lower sealing rubber component 5. Compressed air is filled in from the sealing cavity 10, passes through the ventilation ring grooves Ⅱ19, the gap between the lower sealing rubber component 5 and the pull rod, and finally reaches the outside of the lower sealing structure 2, as shown in FIG. Figure 6The arrow indicates the direction of the sealing wind. A fastening groove 20 is provided on the outer wall of the lower sealing rubber member 5, and a throat hoop 21 is provided in the fastening groove 20. The lower sealing rubber member 5 is fastened to the tie rod through the throat hoop 21 to ensure the sealing effect between the tie rod and the coal mill loading frame, and to prevent coal powder particles from entering the sealing chamber 10. The sealing chamber 10 is continuously filled with compressed air, and its wind pressure is greater than the air pressure outside the upper sealing structure 1 and the lower sealing structure 2, so that the coal powder in the coal mill will not enter the interior of the tie rod sealing device of the coal mill.

[0030] The cover body 3 is provided with a mounting block 23, which is fixedly connected to the lower end cover 9, so as to realize the installation of the lower sealing rubber member 5 with a convenient structure, thereby preventing material overflow and dust leakage between the coal mill discharge pipe and the air flow system.

[0031] like Figure 6 As shown, the lower sealing rubber member 5 has a wing 22, which extends outward, so that there are gaps between the top surface, bottom surface, side surface of the lower sealing rubber member 5 and the top surface, bottom surface, and inner wall of the cavity. When grinding coal, the lower sealing rubber member 5 with the wing 22 absorbs the grinding force of the grinding roller and then absorbs and disperses the grinding kinetic energy, thereby preventing the pull rod from sliding in the lower sealing rubber member 5 due to impact, and reducing the wear between the lower sealing rubber member 5 and the pull rod.

[0032] During installation, the gap between the sealing sleeve 4 and the cover plate 8 is no larger than 0.05mm, the coaxiality deviation between the upper sealing rubber part 6, the lower sealing rubber part 5 and the pull rod is no larger than 0.1mm, and the horizontal angle of the cover surface of the pressure cover 7 and the cover surface of the lower end cover 9 is 15±0.1°. During operation, the pull rod floats forward, backward, up, down, left and right, and the upper sealing rubber part 6 and the lower sealing rubber part 5 are always in contact with the pull rod. Due to the elasticity of the rubber itself, the gap at the pull rod can be guaranteed to be in a very small state for a long time. At the same time, due to the small gap, large coal powder particles cannot enter the sealing cavity 10, and small coal powder particles cannot enter the sealing cavity 10 due to the effect of the sealing wind, which prevents the leakage of coal powder at this place.

[0033] Those skilled in the art should understand that the embodiments of the present invention described above and shown in the accompanying drawings are only examples and do not limit the present invention. The purpose of the present invention has been fully and effectively achieved. The functions and structural principles of the present invention have been demonstrated and explained in the embodiments. Without departing from the principles, the embodiments of the present invention may be deformed or modified in any way.

Claims

1. A rod sealing device for a medium-speed coal mill, comprising an upper sealing structure (1) and a lower sealing structure (2), characterized in that: The upper sealing structure (1) mainly consists of a sleeve (11), a sealing sleeve (4), an upper sealing rubber member (6), a gland (7), and a cover plate (8); the sleeve (11) is installed with the sealing sleeve (4) through the cover plate (8), and the upper sealing rubber member (6) is installed in the sealing sleeve (4); an installation groove (16) is provided on the inner wall of the sealing sleeve (4); an air cavity (24) is provided on the wall of the upper sealing rubber member (6); a positioning step (17) is provided on the upper part of the outer wall of the upper sealing rubber member (6), and a mounting ring (18) is provided on the lower part; the mounting ring (18) is arranged in the mounting groove (16); a gland (7) is provided on the positioning step (17), and the gland (7) is fixedly connected to the end surface of the sealing sleeve (4); the lower sealing structure (2) mainly consists of a cover body (3), a lower sealing rubber member (5), and a lower end cover (9); the lower sealing rubber member (5) is an integrally formed structure, and is installed in a cavity formed by the cover body (3) and the lower end cover (9).

2. The rod sealing device for a medium-speed coal mill according to claim 1, characterized in that: The upper sealing rubber member (6) is made of silicone rubber, and has a plurality of ventilation ring grooves I (12) evenly arranged on its inner wall. Except for the bottom ventilation ring groove I (12), the remaining ventilation ring grooves I (12) are connected to the air cavity (24).

3. The rod sealing device for a medium speed coal mill according to claim 1, characterized in that: The cover plate (8) has a right-angled cross section, one end of which is inserted into the positioning groove (13) of the outer wall of the sealing sleeve (4), and the other end of which is fixedly arranged on the connecting plate (15) of the sleeve (11).

4. The rod sealing device for a medium speed coal mill according to claim 3, characterized in that: An annular gap (14) is provided between the sealing sleeve (4) and the cover plate (8).

5. The rod sealing device for a medium speed coal mill according to claim 4, characterized in that: The sealing sleeve (4) is made of ductile iron, and the gap between the sealing sleeve (4) and the cover plate (8) at the joint surface is no greater than 0.05 mm.

6. The rod sealing device for a medium speed coal mill according to claim 1, characterized in that: The lower sealing rubber component (5) is made of silicone rubber, has a plurality of ventilation ring grooves II (19) formed on its inner wall, and a fastening groove (20) formed on its outer wall, and a throat clamp (21) is disposed in the fastening groove (20).

7. The rod sealing device for a medium speed coal mill according to claim 6, characterized in that: The lower sealing rubber component (5) has a wing portion (22) which extends outwards, so that the top surface, bottom surface, side surfaces of the lower sealing rubber component (5) and the top surface, bottom surface, and inner wall of the cavity have gaps.

8. The rod sealing device for a medium-speed coal mill according to claim 1, characterized in that: A mounting block (23) is provided on the cover body (3), and the mounting block (23) is fixedly connected to the lower end cover (9).

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