JPH0972668A - Roller for conveying substances to be heated for heat treatment furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid damages attributable to a differential temperature of a substance-to- be-heated support member by securing a mutual space for a plurality of substance-to- be-heated support members which form a part of ring shape in the circumferential direction or in the shaft center direction and laying out so that parts of approaching support members may be mutually overlapped in the shaft center direction. SOLUTION: A hearth roller R for conveying substances to be heated is laid out on a furnace floor area H between a furnace ceiling and a furnace bottom so that the top of an outer peripheral part of a support member for the substances may come in contact with one plane and turningly driven so that a hot strip B, which is a substance-to-be-heated, may be conveyed to the outlet. A support surface 2a on the outer peripheral surface of the support member 2 provided on the outer periphery of a roller shaft 1 of the hearth roller R is partially formed on the surface of a disk post and the outer peripheral surface is set so that it may be disk-shaped when viewed in the axial direction of the roller shaft 1. More specifically, two pairs of support members 2 are laid out so that they may be deviated in the circumferential direction. These support members 2 are laid out respectively at a separated position in the shaft center direction, for example, 15mm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heated object transfer roller provided in a hearth of a roller hearth type heat treatment furnace which is a continuous heat treatment furnace, and more specifically, to a roller shaft provided in a hearth part of a heat treatment furnace and its outer periphery. The present invention relates to a heated object conveying roller of a heat treatment furnace of a roller hearth type in which a heated object supporting member is attached along the outer peripheral surface of the heated object supporting member.

[0002]

2. Description of the Related Art Conventionally, in many roller hearth type heat treatment furnaces for continuous heat treatment, in order to avoid cooling of an object to be conveyed, a disk type one having a small contact surface with the object to be heated is often used. It is used. As shown in FIG. 6, this disk-type object-conveying roller comprises a plurality of disks 10, which are annular supporting members, mounted on the axis 1 of the conveying roller at intervals in the longitudinal direction thereof. The outer peripheral surface is exposed and is covered with the refractory heat insulating material 6, and a plurality of pieces are continuously arranged in parallel at the hearth position.
The heated object B is the roller shaft 1 of the heated object conveying roller R.
It is supported in contact with the outer peripheral surface of the disk 10 attached to, and is transported by the rotation of the heated object transport roller R. The object-to-be-heated transfer roller R is rotatably supported and driven outside a through hole provided in the furnace wall 13 of the heat treatment furnace. The roller shaft 1 is formed in a hollow cylindrical shape and is water-cooled from the inside. For this water cooling, a cooling pipe 7 is provided in the roller shaft 1, and the roller shaft 1
A swivel joint is provided on one end of the shaft, and the cooling water inlet 11 is provided for the swivel joint.
After the cooling water W is supplied from the cooling pipe 7 to cool the roller shaft 1, the cooling water W is discharged from a cooling water outlet 12 provided in the swivel joint.

[0003]

As shown in FIGS. 7 and 8, in the above-mentioned conventional article-conveying roller for heating objects, as shown in FIGS.
At the same time that the object to be heated B heated to 200 ° C. comes into contact with the disk 10, it is also exposed to the atmospheric temperature in the furnace, and the temperature of the outer peripheral portion 10a of the disk 10 reaches about 1000 ° C. The temperature of the inner peripheral portion 10b of the disk 10 mounted on the roller shaft 1 is 150 to
It is cooled to 200 ° C. Therefore, the disk 1
The temperature difference between the inside and the outside of 0 exceeds about 800 ° C., and the outer peripheral portion 10a is buckled due to thermal stress, or the inner peripheral portion 1
0b may cause a crack to occur, resulting in damage to the disk 10. For example, the outer diameter of the disk 10 is 30
When the inner diameter is 0 mm and the inner diameter is 110 mm, the outer peripheral portion 10
A compressive stress of about 800 MPa is generated at a, and a tensile stress of about 1600 MPa is generated at the inner peripheral portion 10b as thermal stress. If the disc 10 is damaged in this way, the disc 10 must be replaced in order to be replaced.
Must be slid to the end of the roller shaft 1 and pulled out. For this purpose, the refractory heat insulating material 6 provided between the disks 10 must also be removed, and the object-to-be-heated transfer roller R is set in the furnace. Needs to be removed and dismantled from the
After replacing the disk 10, it is necessary to restore the refractory heat insulating material 6 almost entirely again, and there is a problem that it takes a lot of time and manpower to replace the disk 10. It should be noted that it is conceivable that the disk 10 is provided with a notch in the radial direction or the disk 10 is simply divided in the circumferential direction to relieve the thermal stress. Problems such as mutual biting due to deformation or biting of scales or the like between adjacent divided disks occur, and it is difficult to solve the problem related to thermal stress. Further, since the disk 10 has a contact surface with the object to be heated B over the entire circumference of the object to be heated conveying roller R, the object B to be heated is an outer peripheral surface of the disk 10 having a temperature lower than that temperature. Contacting each of the heated object transfer rollers R
Since both the disks 10 are arranged at the same position, cooling is moderated by the contact thermal resistance between the disk 10 and the object B to be heated, but the object B to be heated has a striped pattern continuous in the transport direction. There was a region where the temperature was somewhat lowered, and the surface to be heated B had an unfavorable surface. Therefore, the present invention solves the above problems, avoids damage caused by the temperature difference of the object-to-be-heated supporting member while maintaining uniform heating of the object-to-be-heated, and when replacing the same, time and An object of the present invention is to provide a heated object transportation roller that does not require human labor.

[0004]

The characteristic constitution of the present invention for the above object is to provide a plurality of the object-to-be-heated support members forming a part of an annular shape in the circumferential direction and the axial center direction of the roller shaft. In addition to disposing some of them that are spaced apart from each other and adjacent to each other so as to overlap each other when viewed in the axial direction, they are detachably attached to the roller shaft (claim 1 Correspondence). With the above configuration,
Since the object-to-be-heated supporting member is configured to form a part of an annular shape, even if the object-to-be-heated supporting surface of the object-to-be-heated supporting member and a portion close to the roller shaft have a large temperature difference. Even if it occurs, due to the deformation of the object-to-be-heated supporting member, a large thermal stress due to the difference in thermal expansion due to the temperature difference between the inside and outside of the circular ring does not occur, and the object-to-be-heated supporting member due to the thermal stress does not occur. Can be prevented, and even if the object-to-be-heated supporting member is damaged, it is possible to replace only the object-to-be-heated supporting member without removing and disassembling the object-to-be-heated conveying roller. Further, since a part of the heated object support members that are arranged close to each other are arranged so as to overlap each other in the axial direction of the roller shaft, when the transferred object is conveyed, the transferred object is conveyed. It prevents rattling and other transport problems, and
The object support member to be heated can be attached and detached, and when replacing the object support member to be heated, the object support member to be heated can be removed as it is, and the labor of removing and disassembling the roller shaft can be omitted. Normally, the periphery of the roller shaft in the portion where the object to be heated supporting member is not provided is provided with a fireproof heat insulating coating, but this fireproof heat insulating coating material also only removes the portion to which the object to be heated supporting member is attached. Even after replacing the object-to-be-heated support member, it suffices to repair the removed fire-resistant heat insulating coating. Moreover, since the object-to-be-heated supporting member is not disposed in the vicinity of the roller shaft in the circumferential direction, there is no possibility that a scale or the like is caught between the object-to-be-heated supporting members. In this configuration, since there is no continuous supporting surface over the entire circumference of the object-to-be-heated conveying roller, the object-to-be-heated is intermittently supported even on the same straight line in the conveying direction. It is possible to prevent striped temperature drop regions. as a result,
While preventing damage to the object to be heated and maintaining uniform heating,
It has become possible to provide a heated object transporting roller that avoids damage due to the temperature difference of the heated object support member and that does not require time and manpower when replacing the object.

Incidentally, the object-to-be-heated supporting members arranged in close proximity may be alternately arranged in a staggered position (corresponding to claim 2). In this way, the object-to-be-heated supports the object to be heated. The point of contact with the member is not biased, unevenness in the temperature distribution of the heated object can be avoided, and the load of the heated object on the heated object support member is equalized. As a result, in addition to the effect of the invention described in claim 1, it becomes possible to further protect the heated object support member while further improving the soaking of the heated object. Further, the plurality of objects to be heated support member,
The supporting surfaces may be provided so as to form a continuous circle when viewed in the axial direction of the roller shaft (corresponding to claim 3). The object to be heated is always in contact with, and the object to be heated can be conveyed without moving up and down. As a result, in addition to the effect of the invention described in each of the above claims, it is possible to prevent the fluctuation of the supporting force for the object to be heated and prevent the object to be deformed and damaged. Further, when the object support member to be heated is attached to the roller shaft, a pin hole penetrating the attachment portion provided on the roller shaft and a pin hole inserted into the object support member to be heated may be attached. Good (corresponding to claim 4). With this configuration, the object-to-be-heated supporting member can be removed only by removing the pin, and the object-to-be-heated supporting member can be attached only by inserting and fixing the pin. Furthermore, if there is slack between the pin and the pin hole, the object support member is not constrained by the mounting part provided on the roller shaft, allowing thermal deformation of the object support member and releasing internal stress easily. Become. As a result, in addition to the effect of the invention described in each of the above claims, it is possible to more reliably prevent damage to the object-to-be-heated supporting member due to the temperature difference between the inside and the outside, and further, the time and labor required for replacing the object-to-be-heated supporting member. Can be significantly reduced and the maintainability of the heated object transfer roller is further improved.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which the present invention is applied to a continuous casting hot strip soaking furnace will be described below with reference to the drawings. As shown in FIG. 1, which shows a vertical cross-section of a part of the soaking furnace, the hearth roller, which is a roller for transporting the object to be heated, is a tunnel furnace, and the furnace roof is similar to a normal roller hearth furnace. In the hearth H between the bottom and the hearth, a number of hearth rollers R are attached to the heated object support member 2 (hereinafter,
It is simply called the support member 2. ) Is arranged so that the upper surface of the outer peripheral portion thereof contacts one flat surface, contacts the lower surface of the hot strip B that is the object to be heated, supports it, and conveys it from the inlet side to the outlet side of the soaking furnace. It is designed to be rotated. A support surface 2 constituted by the outer peripheral surface of the support member 2 provided on the outer circumference of the roller shaft 1 of the hearth roller R.
a is formed on a part of a cylindrical surface, the outer peripheral surfaces of the plurality of support members 2 are circular in the axial direction of the roller shaft 1, and the upper end of the support surface 2a is always constant. It is designed to have a height (see FIGS. 2 and 3). Thus, the hot strip B is heated while being supported on the support surface 2a, and the inside is kept at a uniform temperature. The inside of the soaking furnace is heated by heavy oil combustion gas, and the hot strip B is uniformly heated to 1200 ° C. The hearth roller R is shown in FIG.
FIG. 3 shows a cross section in the axial direction. The roller shaft 1 is a cylindrical hollow shaft having an outer diameter of 110 mm integrally formed. It's cooled down. A mounting portion 1a is provided on the outer surface of the roller shaft 1 so as to face in the diametrical direction, and a support member 2 is mounted via the mounting portion 1a. As shown in FIG. 5, which illustrates a state in which a part of the support member 2 is extended along the outer peripheral surface of the roller shaft 1, two pairs of the support members 2 are arranged in a 90 ° circumferential direction. The pair of support members 2 are arranged in a displaced position, and each of the pair of support members 2 is disposed in the axial direction of the roller shaft 1.
The support members 2 are arranged at positions separated from each other by 5 mm, and the outer circumferences of the support members 2 are formed in a circular shape having a diameter of 300 mm when viewed in the axial direction. Furthermore, in order to project the support surface 2a of the support member 2 around the roller shaft 1,
A castable 6 is wound as a heat insulating material in a cylindrical shape having an outer diameter of 270 mm so as to expose a part of the outer peripheral portion of the support member 2 to keep it heat resistant (see FIG. 4). The castable 6 is applied to the outer surfaces of both side walls of the soaking pit. The arrangement of the pair of support members 2 is 31 in the axial direction.
Repeated at 0 mm intervals, five pairs of the mounting portions 1a having a height of 19 mm are welded to the roller shaft 1, and the mounting portion 1a has three pin holes 3 for inserting the pins 4. It has been penetrated. The central pin hole 3 is formed to have a slightly larger diameter, and a gap is provided between the pin 4 and the central pin hole 3. The support member 2 is formed in an arc shape having a central angle of 100 ° forming a part of an annular shape, and the outer peripheral surface thereof forms a support surface 2a having a radius of curvature of 150 mm for supporting the hot strip B, The inner peripheral surface is formed on a surface along the roller shaft 1 having a radius of curvature of about 55 mm, and a recess for externally fitting the mounting portion 1a is formed on the inner peripheral surface, and both side wall portions of the recess are The mounting part 1
A pin hole 3 for inserting the pin 4 is provided so as to be attached to a. The support member 2 is attached to the roller shaft 1 by externally fitting the recess into the mounting portion 1a, welding a ring 5 to a pin 4 penetrating each pin hole 3, and attaching a ring 5 thereto.

Since the hearth roller is configured as described above, the object support member to be heated is heated in the same manner as in the conventional case, and the temperature of its support surface is 1000 ° C., but its inner peripheral portion is
Since it is attached to the mounting part provided on the roller shaft via a pin that allows the heated object support member to deform, it is not cooled as much as before and is formed in an arc shape, so thermal expansion based on the difference in temperature between inside and outside The difference causes deformation of the object-to-be-heated supporting member as its bending strain, and relaxes thermal stress inside the member. Therefore, it is possible to prevent damage to the object-to-be-heated support member due to thermal stress due to a temperature difference generated in the radial direction.

[Another Embodiment] Next, another embodiment of the present invention will be described. <1> In the above-mentioned embodiment, the article-to-be-heated conveying roller was described as a hearth roller of a soaking furnace for soaking the hot strip. However, the application of the article-to-be-heated conveying roller of the present invention is the above-mentioned soaking. The present invention is not limited to a furnace, and is not limited to a heating furnace for metal heat treatment, and can be suitably used as a transfer means for transferring a heated object to be transferred while avoiding cooling by a transfer roller. It is also applicable to transfer of objects. <2> The shape of the object-to-be-heated supporting member is not limited to the shape shown in the figure, and may be any shape as long as it forms an arc-shaped outer peripheral surface and can be attached to the roller shaft on the inner peripheral side. Therefore, the shape may be such that both end portions in the circumferential direction are externally fitted to the two mounting portions, and in this case, the inner circumferential side of the central portion in the circumferential direction may be omitted. In addition, a section of the object-to-be-heated supporting member in the axial direction of the roller shaft is formed in a T shape, and two mounting portions provided on the roller shaft are arranged side by side in the axial direction of the roller shaft. You may make it fit and attach the inner peripheral side of a to-be-heated material support member between them. It should be noted that the above dimensions are merely examples and do not have any special meaning to the configuration of the present invention. <3> The attachment portion of the object-to-be-heated support member provided on the roller shaft is not limited to welding, and may be provided by any attachment method, or may be formed integrally with the roller shaft. <4> The method of attaching the object-to-be-heated supporting member to the attaching portion is not limited to using pins, but using bolts and nuts,
A bolt may be screwed into a female screw that is screwed in a hole corresponding to the pin hole of the attachment portion or the object-to-be-heated support member, and may be tightened. Alternatively, a detachable attachment method may be adopted. It should be noted that the above dimensions are merely examples and do not have any special meaning to the configuration of the present invention. <5> The arrangement of the object-to-be-heated supporting members on the roller shaft is not limited to the above-described arrangement, and is not limited to the above-mentioned arrangement interval.
For example, the opposed object-to-be-heated support members may be displaced in the axial direction of the roller shaft to form a spiral arrangement.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a front sectional view for explaining a state in which a heated object transporting roller of the present invention is provided in a soaking furnace.

FIG. 2 is a side-view cross-sectional view of an essential part showing an example of the shape and mounting state of the object-to-be-heated supporting member according to the present invention.

FIG. 3 is a cross-sectional view of a main part of a front view showing an example of the shape and mounting state of the object-to-be-heated supporting member according to the present invention.

FIG. 4 is a perspective view of a main part showing an example of the arrangement of an object-to-be-heated supporting member on an object-to-be-heated conveying roller according to the present invention.

FIG. 5 is a development view of a main part showing an example of the arrangement of the object-to-be-heated supporting member of the present invention.

FIG. 6 is a partial cross-sectional view of an essential part for explaining a mounting state of a conventional disk-type object-conveying roller for heating.

FIG. 7 is a cross-sectional view of a main part for explaining a conventional disk-type object-conveying roller for heating.

FIG. 8 is a sectional side view for explaining a conventional disk-type object-conveying roller for heating.

[Explanation of symbols]

 1 Roller Shaft 1a Mounting part for mounting heated object support member 2 Heated object support member 2a Support surface for supporting heated object 3 Pin hole 4 pin

Claims (4)

[Claims] 1. A roller shaft (1) provided in a hearth part of a heat treatment furnace is provided with a heated object support member (2) along its outer circumference, and an outer peripheral surface of the heated object support member (2) is covered. A heated object carrying roller of a roller hearth type heat treatment furnace formed on a heated object support surface (2a), comprising: a plurality of the heated object support members (2) forming a part of an annular shape; The roller shaft (1) is spaced apart from each other in the circumferential direction and the axial center direction, and some of the closely arranged parts are arranged so as to overlap each other in the axial direction, and the roller shaft (1 ) Detachably attached to the heat transfer furnace of the heat treatment furnace. 2. The object-to-be-heated conveying roller for a heat treatment furnace according to claim 1, wherein the object-to-be-heated supporting members (2) arranged in proximity to each other are alternately arranged at staggered positions. 3. The plurality of objects to be heated supporting members (2),
The heated object conveying roller of the heat treatment furnace according to claim 1 or 2, wherein the supporting surfaces (2a) of the rollers are provided so as to form a continuous circle when viewed in the axial direction of the roller shaft (1). . 4. A pin hole (3) penetrating an attachment portion (1a) provided on the roller shaft (1) for attaching the object support member (2) to the roller shaft (1), The heated object transporting roller for a heat treatment furnace according to any one of claims 1 to 3, wherein a pin (4) is inserted into and attached to a pin hole (3) of the heated object support member (2).