JP2001355021A - Device for hanging and supplying radiant tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the supporting positions of a radiant tube at the upper part in a furnace without increasing the number of opening parts in the furnace body iron shell and furnace body refractory and hanging rods, in an indirect heating type heat treatment furnace, to prevent the deformation of the radiant tube in a comparatively cheap device, at a low cost and to remarkably extend the service life of the radiant tube. SOLUTION: In the hanging and supporting device for the radiant tube 2 disposed at the upper part in the heat treatment furnace 1, the hanging rod 11 is hung down in the furnace from a furnace roof part 1a and an arm 12 extended in the horizontal direction is arranged at the lower part of the hanging rod 11. In this arm 12, a plurality of hangers 13 are arranged while holding the interval in the horizontal direction and the radiant tube 2 is supported with these hangers 13 and thus, the radiant tube 2 can be supported at a plurality of positions with one piece of hanging rod 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiant tube suspension support device installed inside a heat treatment furnace used for heat treatment of a steel sheet.

[0002]

2. Description of the Related Art Indirect heat treatment in which gas is burned in a radiant tube (radiant tube) and the radiant heat indirectly heats the steel plate for heat treatment such as normalizing, quenching, and tempering of the steel sheet. A furnace is used. FIG. 3 shows an example of a horizontal indirect heating type heat treatment furnace, in which a radiant tube 2 having a U-shape in plan view is provided at predetermined intervals in the furnace longitudinal direction at the upper part and the lower part in the furnace of the heat treatment furnace 1. A large number of the steel plates 4 are conveyed by the hearth roller 3 and are heated from both upper and lower surfaces.

[0003] The radiant tube 2 has, for example, a support member 5 whose base end is fixedly penetrated to one furnace side wall 1b and whose distal end (U-shaped portion) is fixed to the other furnace side wall 1b, and a tube distal end. The radiant tube 2 is supported by the supported member 6, and in the related art, the center of the radiant tube 2 in the upper part of the furnace is supported by the hanging fitting 50. The radiant tube 2 in the lower part of the furnace is supported by a plurality of supporting bricks 7 installed on the bottom of the furnace body.

A conventional suspending fitting 50 is provided with a suspending rod 51 fixedly penetrating through the furnace body refractory 8 and the furnace body shell 9 of the furnace body ceiling 1a, and integrally provided below the suspending rod 51. And a hanger 52 having an oval shape in a side view that holds two parallel straight pipe portions of the U-shaped radiant tube 2. The hanging rod 51 is fixed to a furnace body by a nut 53 screwed into an upper end of the hanging rod 51. The radiant tube 2 is attached to the ceiling 1a, and the suspension rod 51 is provided with a coil spring 54 so that the displacement of the radiant tube 2 due to heat can be absorbed.

As another conventional technique, for example, Japanese Patent Application Laid-Open No. 5-59425 discloses a U-type non-oxidizing heat treatment furnace.
In a support fitting for supporting a radiant tube such as a V-type, a W-type, or an M-type, a liner made of fine ceramics is attached to an inner surface of a member that holds the radiant tube from below and supports the radiant tube. It is disclosed that a radiant tube that expands and contracts due to heat is smoothly slid to prevent harmful stress from acting on the radiant tube and to prevent bending and cracking of the radiant tube.

Japanese Patent Application Laid-Open No. 8-278001 discloses that when a radiant tube such as a W-shaped tube is installed in a vertical type, the base end of an upper straight pipe of the radiant tube is penetrated through a furnace side wall with a gap. In addition, it is disclosed that by supporting the radiant tube with a torsion bar and a pedestal, the radiant tube is prevented from being cracked or deformed due to thermal distortion or thermal expansion.

[0007]

As a countermeasure for preventing deformation of the radiant tube using the conventional hanging fitting 50, there is a method of increasing the number of supporting portions. As for the radiant tube at the lower part in the furnace, it is only necessary to increase the number of places where the supporting bricks to be piled up from the bottom of the furnace body are to be installed, so that a countermeasure is easy. However, as shown in FIG. 4, when the number of supporting portions of the radiant tube 2 at the upper part of the furnace body is increased, the number of the hanging metal fittings 50 increases, and the furnace body fireproofing at the furnace body ceiling 1 a for attaching the hanging rod 51. Construction work such as drilling of the object 8 and the furnace shell 9 is necessary, which is problematic in terms of cost. Further, even if the number of supporting points is increased by drilling, the supporting position cannot be arbitrarily changed. Therefore, it is difficult to increase the number of support points of the radiant tube at the upper part of the furnace body by using the conventional hanging fitting 50.

Further, even in the support fitting with a liner disclosed in Japanese Patent Application Laid-Open No. 5-59425, it is necessary to increase the number of supporting portions in order to surely prevent the deformation of the radiant tube. JP-A-8-27800
In the method using a torsion bar or the like disclosed in Japanese Patent Application Publication No. 1 (1993), there is a problem that the mounting structure of the radiant tube becomes complicated and the cost increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to increase the number of openings and hanging rods of a furnace shell and a furnace refractory in an indirect heating type heat treatment furnace. It is an object of the present invention to provide a radiant tube suspension support device that can increase the number of radiant tube support locations in the upper part of the furnace without any cost, and can prevent deformation of the radiant tube with a low-cost and relatively inexpensive device. .

[0010]

The radiant tube suspension support device of the present invention is a radiant tube (straight tube type or U-shaped, etc.) suspension support device installed inside a heat treatment furnace. A hanging rod is suspended in the furnace, an arm extending horizontally is provided below the hanging rod, a plurality of hangers are provided on the arm at horizontal intervals, and the radiant tube is supported by the plurality of hangers. It is characterized by doing.

That is, the present invention is configured so that a plurality of hangers can be connected to one hanging rod. For example, the lower part of one hanging rod is perpendicular to the furnace longitudinal direction (radiant tube longitudinal direction). Is mounted, and hangers are suspended from both ends of the arm via hanger rods, and the radiant tube is supported at two points in the longitudinal direction. When the radiant tube is U-shaped, a hanger having a shape that simultaneously holds two parallel straight pipe portions is used.

[0012] In the above configuration, the radiant tube is supported by the plurality of hangers, so that the number of supporting portions of the radiant tube increases, whereby the bending stress acting on the radiant tube is reduced, and the amount of deformation of the radiant tube is reduced. Can be reduced. Also,
Since a plurality of hangers are provided for one hanging rod via an arm, the opening of the furnace shell and the refractory of the furnace body and the supporting point of the radiant tube in the upper part of the furnace can be increased without increasing the number of hanging rods. The radiant tube can be prevented from being deformed at a low cost with a low construction cost and parts cost, and with a relatively inexpensive device. further,
Since one hanger rod is provided with a plurality of hangers via an arm, by changing the length of the arm, it is possible to easily and arbitrarily and easily change the position and the number of support points of the radiant tube.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on one embodiment shown in the drawings. FIG. 1 is a cross-sectional view and a vertical cross-sectional view of a heat treatment furnace showing an example of a radiant tube suspension support device of the present invention. FIG. 2 is a plan view, a front view, and a side view showing an example of an arm portion of the suspension support device of the present invention.

As shown in FIG. 1, a radiant tube suspension support device 10 according to the present invention mainly includes a suspension rod 1.
1, an arm 12, and a plurality of (two in the illustrated example) hangers 13, and a radiant tube (U-shaped in plan view in the illustrated example) 2 in the upper part of the furnace is suspended by the suspension support device 10. Supported.

The other structure is the same as the conventional one. The radiant tube 2 in the lower part of the furnace is supported by the supporting brick 7 on the bottom of the furnace body, and the upper and lower radiant tubes 2 have the base end on one side wall 1b of the furnace. , And its tip (U-shaped portion) is supported by the support member 5 and the supported member 6.

The hanging rod 11 penetrates the furnace body refractory 8 and the furnace body shell 9 of the furnace body ceiling 1a and is attached by a nut 14 screwed into the upper end, as in the prior art.
The displacement of the radiant tube 2 due to heat can be absorbed by a coil spring 15 mounted on the outer circumference of the radiant tube 2.

The arm 12 is, for example, as shown in FIG.
A body 12a having a plate material having a uniform thickness in a plan view, a central portion being large in a front view and gradually decreasing toward both left and right sides,
Attachment pieces 12 projecting horizontally from both sides of the main body 12a
b, 12b, as shown in FIG.
It is fixed to the lower part of the suspending rod 11 so as to extend horizontally below a in the direction perpendicular to the furnace longitudinal direction (steel plate conveying direction). As shown in FIG. 2, a screw hole or an insertion hole 16 is formed in the center of the main body 12a, and the lower portion of the suspension rod 11 is screwed or inserted into the hole 16 and fixed by welding or the like.

As shown in FIG. 2, mounting holes 17 are formed in the pair of left and right mounting pieces 12b, 12b, respectively.
As shown in (a), the hanger 13 is mounted via the hanger rod 18 inserted into the mounting hole 17. The hanger rod 18 may be screwed into the upper portion of the hanger 13 from above, for example, as a bolt member having a large-diameter locking portion at the upper portion.

The hanger 13 is, as in the prior art, used to simultaneously support two parallel straight pipe portions of the U-shaped radiant tube 2, and for example, the radiant tube 2 is sandwiched between upper and lower parallel portions. An oval ring member in a side view.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific materials and dimensions of each member of the suspension support device 10 of the present invention are shown in Table 1 below.

[0021]

[Table 1]

The radiant tube 2 was supported using the hanging support device 10 of the present invention having the materials and dimensions shown in Table 1 and the conventional hanging fitting 50, and the steel plate 4 was subjected to heat treatment. The result was obtained. As is clear from Table 2, in the apparatus according to the embodiment of the present invention, the bending stress acting on the radiant tube 2 was significantly reduced to about 40% of the conventional one due to the increase in the number of the supporting portions.

[0023]

[Table 2]

In the above description, the case where a U-shaped radiant tube is used, the case where two hangers are attached via an arm, the case where an oval-shaped hanger is used, and the like are exemplified. The tube may be a straight tube type or other shapes, the hanger may be attached to three or more on one arm, and the shape of the hanger may be other shapes.

[0025]

Since the present invention has the above-described configuration, the following effects can be obtained.

(1) A hanging rod is suspended from the furnace ceiling into the furnace, and an arm extending horizontally is provided below the hanging rod, and a plurality of hangers are provided on the arm at intervals in the horizontal direction. Since the radiant tube is supported by the plurality of hangers, the number of supporting points of the radiant tube is increased, the bending stress acting on the radiant tube is reduced, and the amount of bending of the radiant tube is reduced, which is relatively simple. Inexpensive equipment can greatly extend the life of the radiant tube.

(2) The number of support points of the radiant tube can be increased by using the existing suspension rods, and the number of openings and the number of suspension rods in the furnace shell and the refractory of the furnace body can be reduced even when adopting at the time of new construction. The number of radiant tube support points can be increased without increasing the number of radiant tubes, and the service life of the radiant tube can be greatly extended with low cost of construction and parts.

(3) Since a plurality of hangers are provided on one suspension rod via an arm, the position and the number of the radiant tube support points can be easily and arbitrarily changed by changing the length of the arm. Can be.

[Brief description of the drawings]

FIG. 1 shows an example of a radiant tube suspension support device of the present invention, wherein (a) is a cross-sectional view of a heat treatment furnace,
(b) is a longitudinal sectional view.

FIGS. 2A and 2B show an example of the suspension support device of FIG. 1, wherein FIG. 2A is a plan view, FIG. 2B is a front view, and FIG.

3A and 3B show a conventional radiant tube hanging bracket, in which FIG. 3A is a cross-sectional view of a heat treatment furnace, and FIG. 3B is a longitudinal cross-sectional view.

FIG. 4 is a cross-sectional view of a heat treatment furnace showing a case where the number of hanging fittings of a conventional radiant tube is increased.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Heat treatment furnace 1a ... Furnace ceiling part 1b ... Furnace side wall part 2 ... Radiant tube 3 ... Hearth roller 4 ... Steel plate 5 ... Support member 6 ... Supported member 7 ... Support brick 8 ... Furnace fire resistance Object 9 Furnace steel shell 10 Hanging support device 11 Hanging rod 12 Arm 12a Body 12b Mounting piece 13 Hanger 14 Nut 15 Coil spring 16 Screw hole or insertion Hole 17 Mounting hole 18 Rod for hanger

Claims (1)

[Claims] 1. A hanging support device for a radiant tube installed inside a heat treatment furnace, wherein a hanging rod is suspended from the furnace ceiling into the furnace, and an arm extending horizontally is provided below the hanging rod. A hanging support device for a radiant tube, wherein a plurality of hangers are provided on the arm at intervals in a horizontal direction, and the radiant tube is supported by the plurality of hangers.