JP2012220173A - Sealing device for rotary kiln - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device for a rotary kiln which efficiently and stably supplies a lubricant between a rotating side seal member and a fixed side seal member without depending on an age-related thermal influence of the rotary kiln and reliably performs life extension for the seal members.SOLUTION: The structure of the sealing device include an annular fixed side seal member 7 attached to a fixing member 4 of the rotary kiln and an annular rotating side seal member 8 attached to a rotation member 3 of the rotary kiln so as to face the fixed side seal member 7 and configured to rotate in the circumferential direction together with the rotation member 3 while being in surface contact with the counterface surface of the fixed side seal member 7 at any time. In addition, a plurality of lubricant supply grooves 14 and 15 supplying a lubricant between the fixed side seal member 7 and the rotating side seal member 8 are provided on the side of a seal surface 11 performing sealing through surface contact between the fixed side seal member 7 and the rotating side seal member 8, and the lubricant supply grooves 14 and 15 are alternately curved in the inner and outer circumferential directions of the seal surface 11 in the whole circumference of the seal surface 11.

Description

  The present invention relates to a sealing device that seals between a rotating member and a fixed member in a rotary kiln for treating waste containing a polymer compound such as a waste tire.

In recent years, recycling of waste tires and other wastes has been promoted from the viewpoint of resource environment protection, and one of them is the thermal decomposition of wastes with a rotary kiln to recover combustible gas, oil, carbon and valuable metals. To be done.
The rotary kiln generally includes a rotating member that is driven to rotate around an axis, and a fixing member such as a housing disposed on both ends of the rotating member in the axial direction. The fixing member rotates both ends of the rotating member. It is configured to be inserted or supported. Then, the workpiece is introduced into the rotating member from the inlet, and the workpiece is heated, baked or dry-distilled and discharged while rotating the rotating member to move the workpiece to the outlet side. .
Since such a rotary kiln is flammable generated in the rotating member, it is necessary to operate by negative pressure control and to prevent outside air from flowing into the rotating member. Since there is a gap between the fixing member and the sealing member, a sealing device for closing the gap in an airtight manner is usually provided.

The sealing device includes an annular fixed-side seal member provided on the fixed member, and an annular rotary-side seal member provided on the rotating member so as to come into contact with the fixed-side seal. When rotating around the axis, there is a configuration in which the rotation-side seal member rotates integrally with the rotation member and slides in the circumferential direction while being always in contact with the fixed-side seal member.
This type of sealing device rotates and slides in the circumferential direction while the rotating side sealing member is always in contact with the stationary side sealing member, so that both sealing members are worn in a short period of time, and the sealing effect is significantly reduced. There was a problem. In particular, in the case of a rotary kiln, when the object to be treated is fired or dry-distilled, the residue tends to enter between the sealing members, so that wear tends to be promoted. For this reason, since it is necessary to replace each sealing member at an early stage in order to maintain the sealing effect, it is very uneconomical.
Therefore, in such a sealing device, as shown in Patent Documents 1 and 2, for example, a lubricant is supplied between the contact surfaces of the rotation-side seal member and the fixed-side seal member on the contact surface side of the fixed-side seal member. An annular groove has been provided, and the lubricant supplied from the annular groove improves the sliding of the contact surfaces of both seal members and suppresses the wear of each seal member. According to the techniques of these cited references 1 and 2, the lubricant can be spread over the entire contact surfaces of both seal members by the contact pressures of the rotary side seal member and the fixed side seal member.

However, although the rotation-side seal member and the stationary-side seal member are prevented from being worn for a while and their lifetime is extended, the surface accuracy of the contact surface is deteriorated due to the heat effect of the rotary kiln over time. For this reason, in the case of a simple annular groove as in the above cited references 1 and 2, the contact pressures of both seal members vary, and there are places where the lubricant spreads and places where the lubricant does not spread.
As a result, the wear increases depending on the location of the rotating side sealing member and the stationary side sealing member, so that the life of the sealing member does not extend so much and often needs to be replaced in several months. It was difficult to reduce the exchange frequency.

Japanese Utility Model Publication No. 63-123998 JP 2010-190462 A

  The technical problem of the present invention is that the lubricant can be efficiently and stably supplied between the rotating side sealing member and the stationary side sealing member regardless of the thermal effects of the rotary kiln over time. It is an object of the present invention to provide a rotary kiln sealing device capable of reliably extending the life of these sealing members.

  In order to solve the above-described problems, a rotary kiln seal device according to the present invention is disposed around a rotating member that is driven to rotate around an axis and into which an object to be processed is placed, and an end of the rotating member in the axial direction. A rotary kiln provided with a fixed member that does not move, and a sealing device that hermetically seals between the rotating member and the fixed member, and an annular fixed side seal member attached to the fixed member; An annular rotation-side seal member that is attached to the rotation member so as to face the fixed-side seal member and rotates in the circumferential direction together with the rotation member in a state where the surface of the fixed-side seal member is always in surface contact with the rotation-side seal member; A plurality of lubricants for supplying lubricant between the fixed side seal member and the rotary side seal member on the seal surface side where the fixed side seal member seals in contact with the rotary side seal member. A supply groove for the agent is provided, and the supply groove is configured to bend alternately in the inner peripheral direction and the outer peripheral direction of the seal surface over the entire circumference of the seal surface. It is.

  In the present invention, the fixed-side seal member has a flow groove that seals by flowing an inert fluid between the fixed-side seal member and the rotary-side seal member at the center portion on the seal surface side. It is provided over the entire circumference, and the supply groove may be provided on the outer peripheral side and the inner peripheral side of the flow groove on the seal surface.

  Moreover, in this invention, the thermal spray material which improves the hardness of each surface is sprayed on the contact surface with the seal surface of the said fixed side seal member, and the seal surface of the fixed side seal member in a rotation side seal member. Preferably.

According to the present invention, the plurality of lubricant supply grooves provided on the seal surface side of the fixed-side seal member are alternately arranged in the inner and outer circumferential directions of the seal surface over the entire circumference of the seal surface. With this configuration, the lubricant can be efficiently supplied to the seal surface of the fixed-side seal member and the contact surface of the rotation-side seal member over a wide range of the seal surface and the contact surface. As a result, the lubricant can be easily spread over the entire seal surface and contact surface, so each surface accuracy between the seal surface of the fixed-side seal member and the contact surface of the rotary-side seal member due to the thermal effects of the rotary kiln over time. Even if the deterioration occurs, the lubricant can be stably supplied between the two seal members.
As a result, since it is possible to effectively suppress the wear of the fixed side seal member and the rotary side seal member, it is possible to reliably extend the life of these seal members as compared with the prior art, and the replacement frequency is also significantly higher. It becomes possible to reduce.

It is a side view which shows typically an example of the rotary kiln with which the sealing device which concerns on this invention was used. It is a partially broken principal part side view of the sealing device which concerns on this invention. It is a front view of the fixed side seal member concerning the present invention.

1 to 3 show an embodiment of a rotary kiln sealing device according to the present invention.
In this embodiment, the case where the sealing device 1 according to the present invention is used in a rotary kiln 2 as shown in FIG. 1 will be described.

As shown in FIG. 1, the rotary kiln 2 in which the sealing device of this embodiment is used includes a cylindrical rotating member 3 into which an object to be processed is placed and an end side in the axial direction of the rotating member 3. And fixed members 4 and 5 which are fixed in position. In addition, the code | symbol 6 in a figure is a support member which supports the said rotation member rotatably.
The rotating member 3 is rotationally driven around an axis line by a rotation driving unit (not shown), and a workpiece to be processed is heated by a heating unit (not shown) such as an external heating furnace. ing. Then, the workpiece is introduced into the interior from the inlet on one end side and is driven to rotate, so that the workpiece is fired or dry distilled while being moved to the outlet side on the other end side, and discharged from the outlet. ing.
On the other hand, the fixing members 4 and 5 are fixed to a stable place such as a foundation, and are respectively provided at both ends of the rotating member 3, and are provided on the inlet side or the outlet side of the rotating member 3. These end portions are rotatably inserted, and the entire rotating member 3 is held in a rotatable state.

In this embodiment, the fixing member 4 on the inlet side is a housing that is used for loading the workpiece into the rotating member 3, while the fixing member 5 on the outlet side is fired and dry-distilled in the rotating member 3. This is a housing for discharging the residue of the object to be processed and the products such as gas and liquid to the outside.
Further, a leaf spring (not shown) is attached to a connecting portion between the end of the rotary member 3 on the outlet side of the rotary kiln 2 and the fixing member 5, and the rotary member 3 is connected to the fixing member 4 on the inlet side. It is always elastically biased in the direction.

And the said sealing apparatus 1 is what seals the clearance gap which arises in the connection part of the said rotation member 3 and the fixing member 4, airtightly, as shown in FIG.1 and FIG.2, the annular | circular shape attached to the fixing member 4 is shown. A fixed-side seal member 7 and an annular rotary-side seal member 8 that is attached to the rotary member 3 so as to face the fixed-side seal member 7 and rotates in the circumferential direction together with the rotary member 3 are provided.
As shown in FIG. 2, the sealing device 1 is configured so that the opposing surfaces of the fixed-side seal member 7 and the rotary-side seal member 7 are always in surface contact with each other, and the rotary member 3 is driven to rotate. The rotation-side seal member 8 is configured to slide while maintaining the state of surface contact with the fixed-side seal member 7.
In this embodiment, the sealing device 1 is arranged only on the rotating member 3, the fixed member 4, and the connecting portion on the inlet side of the rotary kiln 2.

The rotation-side seal member 8 is disposed on the outer periphery of the end portion on the inlet side of the rotation member 3 via a rotation-side mounting member 9 provided in a fixed position in a state of projecting outward from the rotation member 3. It is made of metal (for example, FCD600 or the like) attached in a stationary manner.
The rotation-side seal member 8 has a surface facing the fixed-side seal member 7 as a contact surface 8a with the fixing seal member 7, and the contact surface 8a is a smooth surface over the entire circumference. Is formed. Further, as described above, since the rotating member 3 is biased by the leaf spring in the direction of the fixing member 4 on the inlet side, the rotating side seal member 8 is always pressed against the fixed side seal member 7, It is in a crimped state.
As shown in FIG. 2, the rotation side seal member 8 is attached to the rotation side attachment member 9 through the attachment member 9 and screwed into a surface opposite to the contact surface 8a. This is performed by a plurality of fixing bolts 10, 10, and the entire rotation-side seal member 8 is fixed so as not to move relative to the rotation member 3.

The fixed-side seal member 7 is made of a metal (for example, SUS316L) having a substantially higher inner diameter and outer diameter than the rotation-side seal member 8 and having higher hardness than the material of the rotation-side seal member 8. There are things.
As shown in FIG. 2, the fixed-side seal member 7 has a surface facing the contact surface 8a of the rotating-side seal member 8 as a seal surface 11 that is in surface contact with the contact surface 8a and seals it. The surface opposite to the seal surface 11 is attached to a fixed-side attachment member 12 that is provided in a fixed position on the fixed member 4.
The fixing side sealing member 7 is attached to the fixing side mounting member 12 by a fixing bolt 13 that passes through the mounting member 12 and is screwed into a surface opposite to the sealing surface 11. Accordingly, the fixed-side seal member 7 is fixed so as not to move relative to the fixed member 4.

Also, a plurality of lubricants such as grease are supplied between the fixed side seal member 7 and the rotary side seal member 8 on the seal surface 11 side of the fixed side seal member 7 as shown in FIGS. Between the two seal members by passing an inert fluid (especially gas) such as nitrogen or water vapor between the supply groove for the lubricant and the stationary seal member 7 and the rotary seal member 8 A groove is provided.
In this embodiment, the fixed-side seal member 7 has a configuration in which two supply grooves 14 and 15 and one flow groove 16 are provided on the seal surface 11 side, both of which are the same groove. The depth, the same width, and the same cross-sectional shape are set. Further, the portions other than the supply grooves 14 and 15 and the flow grooves 16 on the seal surface 11, that is, the portion in surface contact with the contact surface 8a of the rotation side seal member 8 are formed to be smooth surfaces.

The flow groove 16 circulates an inert fluid between the stationary seal member 7 and the rotary seal member 8, and seals between the seal surface 11 and the contact surface 8a by this fluid. Thus, the sealing performance as a whole between the sealing surface 11 and the contact surface 8a is further improved.
The flow groove 16 is provided in the central portion on the seal surface 11 side over the entire circumference of the seal surface 11 and is formed in a substantially annular shape in front view that is concentric with the fixed-side seal member 7 as a whole. .
Further, supply holes 16 a for supplying and filling the inert fluid to the flow groove 16 are provided at a plurality of locations in the flow groove 16, and the seal surface 11 of the fixed-side seal member 7 is defined as Fluid is supplied by piping from the opposite surface side.

The supply grooves 14 and 15 are formed at a position on the inner peripheral side of the flow groove 16 (supply groove 14) and a position on the outer peripheral side of the flow groove 16 (supply groove 15) on the seal surface 11 of the fixed-side seal member 7. Each one is provided.
As shown in FIG. 3, each of the supply grooves 14 and 15 is configured to bend alternately in the inner circumferential direction and the outer circumferential direction of the seal surface 11 over the entire circumference of the seal surface 11. In the front view, it is formed in a substantially wave shape.

Specifically, the supply groove 14 located on the inner peripheral side is the minimum that can ensure the rigidity of the groove wall of the supply groove 14 on the inner peripheral edge side of the fixed-side seal member 7 in the innermost peripheral portion. The portion located on the outermost peripheral side is the minimum thickness that can ensure the rigidity of both the groove walls of the flow groove 16 and the supply groove 14 on the adjacent flow groove 16 side. The waveform is biased to a certain position and curved as a whole with a large and gentle curve.
The supply groove 15 positioned on the outer peripheral side has a minimum thickness at which the portion positioned on the innermost peripheral side can secure the rigidity of both the groove grooves of the flow groove 16 and the supply groove 15 on the adjacent flow groove 16 side. The portion located on the outermost peripheral side is offset to the position where the thickness of the groove wall of the supply groove 15 is the minimum thickness that can ensure the rigidity of the groove wall. In addition, the waveform has a large and gently curved shape as a whole.
Further, the supply groove 14 located on the inner peripheral side and the supply groove 15 located on the outer side have substantially the same bent pattern, and both the supply grooves 14 and 15 extend over the entire circumference of the seal surface 11. In this state, the seal surface 11 is bent in the outer peripheral direction and the inner peripheral direction while maintaining a state substantially parallel to each other.
In addition, supply holes 17 for supplying lubricant from a tank or the like (not shown) to the supply grooves are provided at a plurality of locations in the supply grooves 14 and 15, respectively. Lubricants are always replenished in the supply grooves 14 and 15 by piping from the opposite surface side.

Further, in this embodiment, the fixed-side seal member 7 includes an annular seal portion 17 having the seal surface 11 and a fixed side disposed on the fixed member 4 as shown in FIG. It is comprised by the annular fixing part 18 fixed to the member 12 for attachment, The surface on the opposite side to the said seal surface 11 in the seal | sticker part 17, and the member 12 for attachment of the said fixing member 4 in the fixing | fixed part 18 It is formed by joining in a state where the surface opposite to the mounting side is opposed to the mounting side.
In addition, concave grooves 17a and 18a are formed on the respective facing surfaces of the seal portion 17 and the fixing portion 18 over the entire circumference, and the concave grooves 17a and the fixing portion 18 of the seal portion 17 are formed. A coolant such as cooling water for cooling the fixed-side seal member 7 can be circulated in the space 19 formed by the concave groove 18a. The coolant is circulated by a supply hole 20 and a discharge hole 21 which are provided on the outer peripheral surface of the fixed-side seal member 7 and communicate with the space 19 in the fixed-side seal member 7 and the outside. A coolant can be introduced into the space 19 from the use hole 20 and circulated, and then discharged from the discharge hole 21.

By the way, the fixed-side seal member 7 and the rotary-side seal member 8, particularly the seal surface 11 of the fixed-side seal member 7 and the contact surface 8 a of the rotary-side seal member 8 with the seal surface 11 of the fixed-side seal member 7. Is sprayed with a thermal spray material for improving the hardness of the seal surface 11 and the contact surface 8a.
The spraying material is sprayed in this manner because the abrasion powder generated by the sliding of the rotation-side seal member 8 with respect to the fixed-side seal member 7 or the object to be treated in the rotation member 3 is applied to the seal surface 11 and the contact surface 8a. Since residues such as carbonized carbon after the product is carbonized are likely to adhere, and this causes the seal surface 11 and the contact surface 8a to be more easily worn when the rotary side seal member 8 is slid, the thermal spraying is performed. This is because the material is sprayed to increase the hardness of the fixed-side seal member 7 and the rotary-side seal member 8 and to suppress the wear of the seal surface 11 and the contact surface 8a as much as possible.
In this embodiment, the fixed-side seal member 7 is more complicated in configuration than the rotary-side seal member 8, and the hardness of the material is higher and more expensive. Therefore, the frequency of replacement of the fixed-side seal member 7 is high. In order to suppress as much as possible, the thermal spray material sprayed on the fixed-side seal member 7 has a higher hardness than the thermal spray material sprayed on the rotation-side seal member 8.
As a thermal spraying material sprayed on the fixed-side seal member 7, a WB (tungsten boron) -based cermet (Vickers hardness of 900 Hv) having excellent corrosion resistance is suitable, and on the other hand, as a thermal spraying material sprayed on the rotating-side seal member 8 SUS420J2 (Vickers hardness 420Hv), which is relatively inexpensive and has good corrosion resistance, is preferable.

  In the rotary kiln sealing apparatus 1 having the above-described configuration, when the rotary member 3 of the rotary kiln 2 is driven to rotate, the seal surface 11 of the fixed-side seal member 7 and the contact surface 8a of the rotary-side seal member 8 are in surface contact. While the maintained state is maintained, the rotation-side seal member 8 rotates together with the rotation member 3, and the contact surface 8 a slides with respect to the seal surface 11. In the fixed-side seal member 7, the lubricant is supplied and filled in the supply grooves 14 and 15 provided on the seal surface 11 side, and the contact surface between the seal surface 11 of the fixed-side seal member 7 and the rotation-side seal member 8. Lubricant is always supplied to 8a.

At this time, the lubricant supply grooves 14 and 15 of the fixed-side seal member 7 are alternately bent in the inner circumferential direction and the outer circumferential direction of the seal surface 11 over the entire circumference of the seal surface 11. Therefore, each of the supply grooves 14 and 15 applies lubricant to the seal surface 11 of the fixed-side seal member 7 and the contact surface 8a of the rotation-side seal member 8 in the radial direction of the seal surface 11 and the contact surface 8a. In addition to being able to be supplied, the rotation-side seal member 8 rotates and the contact surface 8a slides on the seal surface, so that the lubricant is spread in the circumferential direction of each surface.
Thereby, since the lubricant can be easily spread over the entire seal surface 11 and the contact surface 8a, the contact between the seal surface 11 of the fixed-side seal member 7 and the rotary-side seal member 8 due to the thermal effects of the rotary kiln 2 over time. Even if the surface accuracy with respect to the surface 8a is deteriorated, the lubricant can be stably supplied between the seal members 7 and 8.

  As a result, it becomes possible to effectively suppress the wear of the fixed-side seal member 7 and the rotary-side seal member 8, so that the life of these seal members can be reliably extended as compared with the prior art. The frequency can be greatly reduced. In this regard, although depending on the use conditions of the rotary kiln, it can be seen that the sealing device of the above embodiment can maintain a sufficient sealing effect without replacing any sealing member for two years or more. It has been proved by the inventors that the life of the seal member has been significantly increased compared to the prior art.

In the above embodiment, a total of two lubricants are supplied to the seal surface 11 of the fixed-side seal member 7, one for each flow groove 16 and one for the inner and outer peripheral sides of the flow groove 16. Although the supply grooves 14 and 15 are provided, the sealing surface of the fixed-side seal member is not necessarily required to have such a structure, and any structure having at least two supply grooves may be used.
Further, the supply groove need not necessarily have a wave shape as shown in FIG. 3 as long as the supply groove is alternately bent in the inner circumferential direction and the outer circumferential direction over the entire circumference of the seal surface. It can be made into an appropriate shape. Further, the bent patterns of the supply grooves are preferably matched with each other as in the above-described embodiment, but are not necessarily matched, and may be arbitrary patterns.

  In the above-described embodiment, WB cermet and SUS420J2 are respectively employed as the thermal spraying material sprayed onto the seal surface 11 of the fixed-side seal member 7 and the contact surface 8a of the rotation-side seal member 8 with the seal surface 11. However, for example, an arbitrary thermal spraying material such as one made of a material such as WC (tungsten carbide) -NiCr can be adopted. In this case, it is preferable to use a thermal spraying material with excellent corrosion resistance, and the thermal spraying material sprayed on the fixed-side seal member has a higher hardness than that sprayed on the rotating-side seal member. It is preferable to do this.

  Furthermore, in the above-described embodiment, the fixed-side seal member 7 is constituted by the seal portion 17 and the fixed portion 18, and the concave portions formed on the respective facing surfaces of the seal portion 17 and the fixed portion 18. Although the space 19 for circulating the coolant is provided by the grooves 17a and 18a, the fixed-side seal member 7 does not necessarily have such a configuration. If there are a plurality of supply grooves on the seal surface, the above space is provided. It can be of a simple configuration that does not have.

DESCRIPTION OF SYMBOLS 1 Sealing device 2 Rotary kiln 3 Rotating member 4,5 Fixed member 7 Fixed side sealing member 8 Rotating side sealing member 8a Contact surface in rotating side sealing member 11 Seal surface 14, 15 Supply groove 16 Distribution groove

Claims (3)

These rotations in a rotary kiln comprising a rotating member that is driven to rotate around an axis and into which an object to be processed is placed, and a stationary member that is fixed on the end of the rotating member in the axial direction. A sealing device that hermetically seals between a member and a fixing member,
An annular fixed side seal member attached to the fixed member, and attached to the rotating member so as to oppose the fixed side seal member, and rotated in a state of constant surface contact with the opposing surface of the fixed side seal member. An annular rotation side seal member that rotates in the circumferential direction together with the member,
Supply grooves for a plurality of lubricants for supplying a lubricant between the fixed side seal member and the rotary side seal member on the seal surface side where the fixed side seal member seals in contact with the rotary side seal member With
2. The rotary kiln seal device according to claim 1, wherein the supply groove is configured to bend alternately in an inner circumferential direction and an outer circumferential direction of the seal surface over the entire circumference of the seal surface.   The fixed-side seal member has a circulation groove that seals by flowing an inert fluid between the fixed-side seal member and the rotary-side seal member in the central portion on the seal surface side, over the entire circumference of the seal surface. The rotary kiln sealing device according to claim 1, wherein the supply groove is provided on an outer peripheral side and an inner peripheral side of the flow groove on the seal surface. The thermal spray material which improves the hardness of each surface is sprayed on the contact surface with the seal surface of the above-mentioned fixed side seal member, and the seal surface of the fixed side seal member in the rotation side seal member. The sealing device of the rotary kiln of Claim 1 or Claim 2.

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