Tensioning labyrinth type rotary sealing device

Abstract

According to the tensioning type labyrinth rotary sealing device, the containing groove is formed in the sealing cover, the sealing base is movably arranged in the containing groove, meanwhile, the expansion joint is arranged on the sealing cover, and the sealing cover is connected to a cover body of a kiln head or a kiln tail of a rotary kiln through the expansion joint. Even if the linear expansion amount is different due to different heating temperatures, and the sealing base axially moves after being expanded, the sealing cover can be driven to synchronously move in the axial direction. According to the scheme, the sealing cover, the sealing base and the barrel can synchronously move in the axial direction through expansion and contraction of the expansion joint, and the problem that the sealing cover and the sealing base are staggered is effectively avoided; according to the scheme, the sealing device is of a novel labyrinth type and friction type structure, the sealing time between the rotating barrel of the rotary kiln and the cover bodies of the kiln head and the kiln tail can be effectively prolonged, and the sealing device is particularly suitable for the high-temperature working environment.

Description

Technical Field

[0001] The utility model relates to the technical field of large-scale rotary seals, in particular to a tensioned labyrinth rotary seal device. Background Technique

[0002] A rotary kiln refers to a rotary calcining kiln. Rotary kilns can be divided into cement kilns, metallurgical and chemical kilns, and lime kilns according to the materials processed. There are gaps between the rotating cylinder body of the rotary kiln and the covers at the kiln head and kiln tail. In order to prevent external air from being sucked into the rotary equipment and to prevent the internal gas of the rotary kiln from leaking, a sealing device needs to be provided between the cylinder body of the rotary kiln and the cover. There are many types of sealing structures for rotary kilns, and the labyrinth plus packing sealing structure is a relatively common one. For example, the patent with the publication number CN107642984A discloses a new type of graphite sealing device for the kiln head of a rotary kiln. However, it is found in actual use that in the application of metallurgical and chemical kilns, the sealing device with a metal structure works in a high-temperature environment. After long-term use, due to different heating temperatures, the linear expansion amounts are different, resulting in structural deformation, and then the components of the sealing structure are misaligned, ultimately leading to the occurrence of air leakage problems. Summary of the Invention

[0003] In order to solve the problem that the existing sealing device of the rotary kiln has poor sealing effect after working in a high-temperature environment for a long time, the utility model provides a tensioned labyrinth rotary seal device, which can effectively extend the sealing time between the rotating cylinder body of the rotary kiln and the covers at the kiln head and kiln tail, and is especially suitable for high-temperature working environments.

[0004] The structure of the utility model is as follows: a tensioned labyrinth rotary seal device, which includes: an annular sealing cover and an annular sealing base. The sealing cover and the sealing base are coaxially arranged on the outer circumference of the cylinder body of the rotary kiln. The sealing base is fixed on the cylinder body, and the sealing cover is connected to the cover of the rotary kiln; the cover includes a kiln head cover and a kiln tail cover;

[0005] It is characterized in that:

[0006] It further includes: a fixing frame, which is arranged on the outer periphery of the sealing cover. A chute is arranged on the fixing frame along the axial direction of the rotary kiln cylinder body; a positioning slider is arranged on the sealing cover, and the positioning slider is slidably installed in the chute;

[0007] At the bottom of the sealing cover adjacent to the sealing base side, a coaxial accommodating groove is opened along the circumferential direction of the circle; the sealing base is movably arranged in the accommodating groove;

[0008] One end of the sealing cover connecting the cover body is provided with an annular expansion joint. One end of the expansion joint away from the sealing cover is provided with a connecting cylinder section, and the connecting cylinder section is fixedly connected to the cover body on the rotary kiln.

[0009] Its further features are as follows:

[0010] It also includes: a sealing ring and graphite packing;

[0011] A ring-shaped first sealing groove is coaxially opened on the sealing cover with the accommodating groove; the first sealing groove communicates with the accommodating groove;

[0012] One end of the sealing base adjacent to the sealing cover is provided with a second sealing groove; when the sealing base is placed in the accommodating groove, the position and width of the second sealing groove correspond to those of the first sealing groove, and the second sealing groove communicates with the accommodating groove and the first sealing groove, and the two form an annular sealing cavity;

[0013] The sealing ring is arranged in the first sealing groove, and the graphite packing is arranged in the second sealing groove;

[0014] Two first sealing grooves are provided and evenly opened on the sealing cover; two second sealing grooves are provided and evenly arranged on the sealing base;

[0015] The sealing ring includes a plurality of sealing ring segments, and the plurality of sealing ring segments are evenly arranged in the first sealing groove, and the segments form an annular sealing ring;

[0016] It also includes: a leaf spring,

[0017] The leaf spring is placed in the first sealing groove and located on the outer arc side of the sealing ring away from the graphite packing;

[0018] The two ends of the leaf spring are respectively: a pressing end and a fixed end;

[0019] The fixed end of the leaf spring is fixedly connected to the inner wall of the first sealing groove; the pressing end presses against the outer arc of the sealing ring segment, and the contact surface of the pressing end of the leaf spring is tangent to the outer arc surface of the sealing ring segment it presses against;

[0020] A positioning pin is arranged on the sealing ring, a waist-shaped hole is arranged on the pressing end of the leaf spring, and the positioning pin is installed in the waist-shaped hole to connect the sealing ring and the pressing end of the leaf spring;

[0021] Two leaf springs are correspondingly arranged for each sealing ring segment; the pressing ends and fixed ends of the two leaf springs on the same sealing ring segment are axially symmetrically arranged based on the center of the sealing ring segment;

[0022] The connecting cylinder section is fixedly connected to the cover body on the rotary kiln based on a flange.

[0023] A tensioned labyrinth rotary seal device provided in this application has a receiving groove provided on the seal cover, and the seal base is movably arranged in the receiving groove. At the same time, an expansion joint is provided on the seal cover and is connected to the cover body at the head or tail of the rotary kiln through the expansion joint. When used for a long time in a high-temperature environment, even if the linear expansion amounts are different due to different heating temperatures, when the seal base expands and generates an axial movement, it can drive the seal cover to move synchronously along the axis. In this solution, the expansion and contraction of the expansion joint can enable the seal cover, the seal base, and the cylinder body to move synchronously in the axial direction, effectively avoiding the problem of misalignment between the seal cover and the seal base; this solution is a new type of seal device that combines a labyrinth type and a friction type, which can effectively extend the sealing time between the rotating cylinder body of the rotary kiln and the cover bodies at the head and tail, and is particularly suitable for a high-temperature working environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of the connection relationship of the tensioned labyrinth rotary seal device in this application;

[0025] Figure 2 Schematic diagram of the front view of the tensioned labyrinth rotary seal device;

[0026] Figure 3 Schematic diagram of the top view of the tensioned labyrinth rotary seal device;

[0027] Figure 4 For Figure 2 Schematic diagram of the sectional structure of the B-B direction;

[0028] Figure 5 For Figure 4 Enlarged structural diagram at position C in

[0029] Figure 6 For Figure 3 Schematic diagram of the sectional structure of the A-A direction;

[0030] Figure 7 For Figure 6 Enlarged structural diagram at position D in

[0031] Figure 8 Schematic diagram of the structure of the seal cover;

[0032] Figure 9 For Figure 8 Enlarged structural diagram at position E in

[0033] Figure 10 Partial 3D structural diagram of the seal cover and the seal base. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] The utility model includes a tension type labyrinth rotary seal device, which comprises: an annular seal cover 3, an annular seal base 4, a leaf spring 305, a seal ring 303 and a graphite packing 401.

[0035] As Figure 1 , Figure 2 , Figure 3 and Figure 10 shown, the seal cover 3 and the seal base 4 are coaxially arranged on the outer circumference of the cylinder body 1 of the rotary kiln. The specific installation method is as follows: the seal base 4 is fixed on the outer circle of the cylinder body 1, and the seal cover 3 covers the seal base 4, so that the seal base 4 is placed in the concave accommodating groove of the seal cover 3. The seal base 4 rotates synchronously with the cylinder body 1. The seal cover 3 is connected to the cover body 2 of the rotary kiln. The cover body 2 can be a head cover of the kiln or a tail cover of the kiln.

[0036] In this embodiment, the connecting cylinder section 7 is fixedly connected to the cover body 2 on the rotary kiln based on the flange 6. Based on the fixed structure in the prior art, the radial form of the seal cover 3 and the seal base 4 is a suspended non-contact structure, ensuring that when the seal base 4 and the cylinder body 1 rotate, the seal cover 3 and the cover body 2 on the rotary kiln are circumferentially fixed.

[0037] During specific application, for the convenience of installation, as Figure 4 shown, the seal cover 3 includes two semi-circular ring structures, which are fixed into a complete annular seal cover by a connecting piece 305.

[0038] As Figure 4 and Figure 5 shown, a fixing frame 8 is arranged on the outer periphery of the seal cover 3, and a sliding groove 801 is arranged along the axial direction of the rotary kiln cylinder body 1 on the fixing frame 8; a positioning slider 304 is arranged on the seal cover 3, and the positioning slider 304 is slidably installed in the sliding groove 801. The assembly position of the positioning slider 304 and the sliding groove 801 is used to ensure that the annular seal cover 3 floats on the seal base 4, and at the same time, ensure the sliding of the positioning slider 304 in the positioning sliding groove 801, so as to ensure that the seal cover 3 can move freely axially.

[0039] As Figure 6 and Figure 7 shown, a coaxial accommodating groove 301 is opened along the circumferential direction at the bottom of the seal cover 3 adjacent to the seal base 4; the width of the accommodating groove 301 is slightly larger than the width of the seal base 4, and the seal base 4 is movably arranged in the accommodating groove 301. That is, the cross-section of the seal cover 3 along the diameter direction is a concave-shaped structure.

[0040] An annular expansion joint 5 is arranged at one end of the seal cover 3 connecting to the cover body 2, a connecting cylinder section 7 is arranged between the annular expansion joint 5 and the flange 6, and the connecting cylinder section 7 is fixedly connected to the cover body 2 of the rotary kiln through the flange 6.

[0041] In the tensioned labyrinth rotary sealing device of the present application, the sealing cover 3, the sealing base 4, the sealing ring 303, the leaf spring 305, the expansion joint 5, and the connecting barrel section 7 are all metal structures. In a high-temperature environment, due to different heating temperatures, metals will have different linear expansion amounts, and it is very easy for structural components to be misaligned. In order to ensure that the relative positions between the sealing cover 3 and the sealing base 4 remain unchanged, the sealing cover 3 adopts a concave structure. Even when the sealing base 4 expands axially due to the heating of the cylinder body, it can drive the sealing cover 3 in the chute 801 of the fixing frame 8, and use the expansion and contraction of the expansion joint 5 to make the sealing cover 3 move axially synchronously with the sealing base 4 and the cylinder body 1. At the same time, the concave structure of the sealing cover 3 blocks the heat radiation of the high temperature in the rotary kiln to the leaf spring 305, preventing the leaf spring 305 from failing due to long-term high-temperature radiation, and also effectively blocking solid particles from entering the sealing cavity.

[0042] A connecting barrel section, a flange are arranged at the other end of the expansion joint and form a sealing device together with the sealing cover and the sealing base. The flange is fixed on the kiln head (tail) cover to achieve the purpose of sealing between the cylinder body and the kiln head (tail) cover.

[0043] The receiving groove 301 of the sealing cover 3 coaxially opens a ring-shaped first sealing groove 302; the first sealing groove 302 communicates with the receiving groove 301.

[0044] One end of the sealing base 4 adjacent to the sealing cover 3 opens a second sealing groove 402; when the sealing base 4 is placed in the receiving groove 301, the position and width of the second sealing groove 402 correspond to those of the first sealing groove 302, and the second sealing groove 402 communicates with the receiving groove 301 and the first sealing groove 302, and the two form an annular sealing cavity.

[0045] The sealing ring 303 is arranged in the first sealing groove 302, and the graphite packing 401 is arranged in the second sealing groove 402. The sealing ring 303 presses on the graphite packing to block the suspension gap between the sealing cover 3 and the sealing base 4. Two first sealing grooves 302 are provided and evenly opened on the sealing cover 3; two second sealing grooves 402 are provided and evenly opened on the sealing base 4 to form two sealing cavities, which form a labyrinth structure with the sealing ring 303 and the graphite packing 401 and can provide better sealing performance.

[0046] As Figure 8 and 9 shown, the sealing ring 303 includes a plurality of sealing ring segments 3031. The plurality of sealing ring segments 3031 are evenly arranged in the sealing cavity formed by the first sealing groove 302 and the lower sealing groove 402 to form an annular sealing ring 303.

[0047] The leaf spring 305 is arranged in the first sealing groove 302 and is located between the sealing ring 303 and the upper sealing groove 302.

[0048] The two ends of the leaf spring are respectively a pressing end and a fixed end 3051; the fixed end 3051 of the leaf spring 305 is fixed on the inner wall of the first sealing groove 302; the pressing end at the other end presses against the outer arc of the sealing ring section 3031, and the contact surface of the pressing end of the leaf spring 305 is tangent to the outer arc surface of the sealing ring section 3031 against which it presses. A positioning pin 306 is provided on the sealing ring 303, and a waist-shaped hole 3052 is provided on the pressing end of the leaf spring 305. The positioning pin 306 is installed in the waist-shaped hole 3052 to position and connect the pressing end of the sealing ring 303 and the leaf spring 305.

[0049] In this embodiment, 4 sealing ring sections 3031 are provided to form a circumferential sealing ring 303. Each two leaf springs 305 position one sealing ring section 3031. The leaf springs 305 are also evenly arranged on the circumference of the sealing cover 3 based on the first sealing groove 302 to press the sealing ring section 3031, so that the sealing ring 303 and the graphite packing 401 are always in close contact, improving the sealing effect; at the same time, through the setting of the waist-shaped hole 3052 and the positioning pin 306, it is ensured that the sealing ring section 3031 can move freely in the radial direction in the first sealing groove 302, ensuring that even if the graphite packing 401 wears, the sealing ring 303 can still always press the graphite packing 401 to maintain the sealing effect.

[0050] Two leaf springs 305 are correspondingly provided for each sealing ring section 3031; the pressing ends and the fixed ends 3051 of the two leaf springs 305 on the same sealing ring section 3031 are arranged symmetrically across the axis based on the center of the sealing ring section 3031. As Figure 4 shown, since the working condition of this rotary kiln is reciprocating rotation in both positive and negative directions, the leaf spring 305 adopts a symmetric arrangement structure form in the first sealing groove 302 to satisfy that the leaf spring is tangent to the upper arc surface of the sealing ring 303 in both positive and negative rotation directions, ensuring that the elastic force of the leaf spring 305 is always in the radial direction, making the sealing ring 303 and the graphite packing 401 always in close contact, preventing air leakage from the side, so as to achieve the purpose of sealing.

[0051] After using the technical solution of the present utility model, based on the radially tensioned labyrinth sealing structure, the leaf spring provided in the sealing cover makes the sealing ring always in close contact with the graphite packing in the labyrinth during the rotation of the cylinder body, preventing air from leaking into the kiln from the side gap, and at the same time preventing harmful gases in the kiln from leaking out of the kiln, achieving the purpose of sealing.

Claims

1. A tensioning labyrinth type rotary sealing device, comprising: An annular sealing cover and an annular sealing base, the sealing cover and the sealing base are coaxially arranged on the outer circumference of the cylinder of the rotary kiln, the sealing base is fixed on the cylinder, and the sealing cover is connected to the cover body of the rotary kiln; the cover body includes a kiln head cover and a kiln tail cover; Features: It also includes: a fixing frame, the fixing frame is arranged on the outer periphery of the sealing cover, and a slide groove is arranged on the fixing frame along the axial direction of the rotary kiln cylinder; a positioning slider is arranged on the sealing cover, and the positioning slider is slidably installed in the slide groove; The sealing cover is provided with a coaxial receiving groove along a circular direction at the bottom of one side adjacent to the sealing base; the sealing base is movably arranged in the receiving groove; An annular expansion joint is arranged at one end of the sealing cover connected to the cover body, and a connecting cylinder section is arranged at one end of the expansion joint away from the sealing cover, and the connecting cylinder section is fixedly connected to the cover body on the rotary kiln.

2. The tensioned labyrinth rotary seal device according to claim 1, characterized in that: It also includes: sealing rings and graphite packing; The sealing cover is provided with an annular first sealing groove coaxially with the containing groove; the first sealing groove is communicated with the containing groove; A second sealing groove is provided on one end of the sealing base adjacent to the sealing cover; when the sealing base is placed in the receiving groove, the position and width of the second sealing groove correspond to those of the first sealing groove, and the second sealing groove is connected to the receiving groove and the first sealing groove, and the two form an annular sealing cavity; The sealing ring is arranged in the first sealing groove, and the graphite packing is arranged in the second sealing groove.

3. The tensioned labyrinth rotary seal device according to claim 2, characterized in that: Two first sealing grooves are provided and are evenly arranged on the sealing cover; two second sealing grooves are provided and are evenly arranged on the sealing base.

4. The tensioned labyrinth rotary seal device according to claim 2, characterized in that: The sealing ring comprises a plurality of sealing ring segments, which are evenly arranged in the first sealing groove, and the segments form an annular sealing ring.

5. A tensioned labyrinth rotary seal device according to claim 4, characterized in that: It also includes: leaf springs, The leaf spring is placed in the first sealing groove and is located on the outer arc side of the sealing ring away from the graphite packing; The two ends of the leaf spring are respectively: a pressing end and a fixed end; The fixed end of the leaf spring is fixedly connected to the inner wall of the first sealing groove; the pressing end presses on the outer arc of the sealing ring segment, and the contact surface of the pressing end of the leaf spring is tangent to the outer arc surface of the sealing ring segment it presses.

6. The tensioned labyrinth rotary seal device according to claim 5, characterized in that: A positioning pin is arranged on the sealing ring, a waist-shaped hole is arranged on the pressing end of the leaf spring, and the positioning pin is installed in the waist-shaped hole to connect the sealing ring and the pressing end of the leaf spring.

7. The tensioned labyrinth rotary seal device according to claim 5, characterized in that: Two leaf springs are correspondingly arranged for each sealing ring segment; the pressing ends and the fixed ends of the two leaf springs on the same sealing ring segment are symmetrically arranged across the axis based on the center of the sealing ring segment.

8. The tensioned labyrinth rotary seal device according to claim 1, characterized in that: The connecting cylinder section is fixedly connected to the cover body on the rotary kiln based on a flange.

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