JPH0596053U - Atmospheric gas sealing device for heat treatment furnace - Google Patents

Abstract

(57) [Summary] [Purpose] To securely seal the hem of the inner cover. [Structure] A base plate 12 of a heat treatment furnace which is made of metal and has a planar shape, an inner cover having an arc-shaped flange 22 mounted on the base plate, and a heat-resistant rubber seal ring 14 inserted into the flange portion. And a clamp head 41 that mechanically presses the flange 22 of the inner cover against the base plate 12.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an atmosphere gas sealing device in a box-shaped heat treatment furnace for batch heat treatment of thin steel plates and the like.

[0002]

[Prior Art]

 In a box-type heat treatment furnace that heat-processes thin steel plates in batches, such as a batch annealing furnace, place the coil on the base, cover the inner cover, and then cover the inner furnace body as shown in Fig. 1. A reducing atmosphere gas is supplied to the inside of the cover, and the inner cover is indirectly heated in the atmosphere gas by heating the inner cover by a heating means such as a burner provided in the furnace body to perform heat treatment. Is normal. At this time, in order to uniformly heat the coil in the inner cover, a circulation fan for circulating atmospheric gas is provided below the base.

The atmospheric gas is not only an expensive gas adjusted to a specific component but also explosive depending on the component, and prevents gas leakage to the outside of the inner cover, especially to the combustion chamber inside the furnace. This is very important. For this reason, some kind of gas seal structure is used at the hem of the inner cover. The pressure of the atmospheric gas is, for example, about 1.0 kg / cm ^{2 in} gauge pressure. Normally, a seal structure is used in which the grooves provided on the outer periphery of the base are filled with granular refractory and the hem of the inner cover is embedded by its own weight. However, if the atmospheric gas pressure in the inner cover is high or if the granular refractory is not sufficiently filled, there is a problem that a leak may occur.

Therefore, for example, in Japanese Utility Model Publication No. 54-40414, a double groove is provided in the hem portion of the inner cover, a solid sealing material made of ceramic fiber is inserted in the inner groove, and the outer groove is sealed with water. As a structure, a seal structure is shown that allows an inert gas to flow in the water seal portion. In addition, in Japanese Utility Model Publication No. 59-149962, the water seal portion in Japanese Utility Model Publication No. 54-40414 is further referred to as a water reservoir portion. It has been proposed to divide it into an oil sump and combine it with a solid seal material to form a triple seal structure.

[0005]

[Problems to be solved by the device]

 By the way, a seal structure that also uses such a water seal structure is effective as a means for preventing the leakage of atmospheric gas, but the hem of the inner cover is extremely complicated and the furnace body becomes large. However, it has not been put to practical use because there is a problem that the water and oil used in the water seal part vaporize in the furnace and adversely affect the quality and operation.

An object of the present invention is to realize a seal structure which does not have such problems and which surely prevents leakage of atmospheric gas with a simple structure.

[0007]

[Means for Solving the Problems]

 The present invention is an atmospheric gas sealing device for a heat treatment furnace that seals the inside of an inner cover filled with atmospheric gas and the combustion chamber formed on the outside of the inner cover, containing the material to be treated. A base plate of the heat treatment furnace which is made of metal and has a flat shape, an inner cover having a flange mounted on the base plate, and a heat-resistant seal which is inserted into a contact portion between the base plate and the flange of the inner cover. And a clamp means for mechanically pressing the flange of the inner cover against the base plate.

[0008]

[Work]

 According to the present invention, the base plate and the inner cover flange are in contact with each other by a flat metal surface, and a heat-resistant seal member is provided for the gap between the contact surfaces mainly caused by the strain generated on the inner cover flange side. By sealing and pressing the flange of the inner cover against the base plate by the mechanical clamping means, the gap between the contact surfaces is reduced and the heat resistant seal member is crushed surely to form a complete seal structure. ..

[0009]

【Example】

 Embodiment 1 A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an overall vertical cross-sectional view of a batch type coil annealing furnace which is an example of a heat treatment furnace. After stacking a predetermined number of coils C on a furnace bottom 1 installed in a pit provided on the factory floor, an inner cover is provided. 2, the furnace body 3 is further covered thereon, and a predetermined heat treatment is carried out while supplying the atmosphere gas from the furnace bottom 1 into the inner cover 2.

In the furnace body 3, a refractory material 32 is mounted on the inner surface of a steel structure 31, a plurality of burners 33 are provided on the side surfaces, and one or several chimneys 34 are provided on the upper portion. The inside of the refractory material is the combustion chamber. The furnace bottom 1 has a pedestal 11 installed in a pit and a base plate 12 mounted on the pedestal 11. The upper surface of the base plate 12 is usually on the same level as the floor surface around the pit. A circulating fan 13 for circulating atmospheric gas is installed at the center of the base plate 12. The inner cover 2 has an arc-shaped flange 22 that opens in the semi-diametrical direction at the lower end of a cylindrical body 21 with the top closed, and this flange 22 is placed on the upper surface of the base plate 12 and is clamped by a clamp mechanism 4 described in detail later. It is firmly fixed to the plate 12. A shallow arc-shaped groove is cut in the portion of the upper surface of the base plate 12 where the flange 22 of the inner cover 2 is to be placed, and in this groove, a seal ring 14 made of heat-resistant rubber having a wire diameter larger than the depth of this groove is formed. Has been inserted. When the flange 22 is clamped to the base plate 12 as described above, the seal ring 14 is crushed and the inside of the inner cover 2 is completely sealed from the combustion chamber 35 in the furnace.

An atmosphere gas supply pipe 15 and an atmosphere gas discharge pipe 16 are opened inside the portion of the upper surface of the base plate 12 where the flange 22 of the inner cover 2 is placed. 2 (a) and 2 (b) are detailed cross-sectional views of the clamp mechanism 4 shown as A in FIG. 1, 21 is a cylindrical body of the inner cover, 22 is a flange, and 23 is provided on this flange portion. A rectangular clamp hole, 12 is a base plate, 14 is a seal ring, 41 is a clamp head, 42 is a clamp cylinder, 43 is a timing belt, 44 is a swivel motor, 45 is a swivel bearing, and 46 is a support frame. A clamp cylinder 42 having a T-shaped clamp head 41 at the tip of the rod that moves in and out is supported by a support frame 46 attached to the lower surface of the base plate 12 via a swivel bearing 45, and is freely centered around the rod. You can turn. On the other hand, since the lower part of the clamp cylinder 42 is connected to the swing motor 44 by the timing belt 43, the clamp head 41 can be moved up and down by the operation of the clamp cylinder 42 and rotated by the swing motor 44.

FIG. 2A shows a state immediately after the inner cover 2 is placed on the base plate 12, and the clamp head 41 is hidden below the upper surface of the base plate 12. In FIG. 2B, first, the cylinder 42 is moved forward to raise the clamp head 41 to a position above the flange 22 above the base plate 12, and then the turning motor 44 is operated to turn the clamp head 41 about 90 degrees. Let 3 (a) and 3 (b) are plan views of this clamping mechanism.

The flange 22 of the inner cover 2 is originally attached at a right angle to the tubular body 21, but is deformed due to use under high temperature and is no longer a right angle as illustrated in FIG. 2A. Often Taking an example of an inner cover with a diameter of 2000 mm, a height of 5000 mm, and a plate thickness of 20 mm, the self-weight is about 8 tons. Normally, the self-weight of the inner cover 2 does not bring the flange 22 and the base plate 12 into close contact, and there is a gap between them. Is occurring. Therefore, when the clamp head 41 is rotated and then the clamp cylinder 42 is retracted again, the flange 22 is pulled downward by the T-shaped portion and adheres to the base plate 12, and at the same time, the seal ring 14 is crushed to achieve a reliable seal. To be done.

When disassembling the inner cover 2, the above procedure is reversed, the clamp cylinder 42 is loosened and then rotated 90 degrees so that the direction of the clamp head 41 matches the direction of the clamp hole 23 of the flange 22. Then, the clamp head 41 is lowered. By providing such a clamp mechanism on the flange 22 of the inner cover 2 at approximately equal intervals and in an appropriate number according to the pressure of the atmospheric gas, the flange 22 can be clamped almost uniformly. The inner cover 2 must be placed at the correct position with respect to the base plate 12 in order for this clamp mechanism to operate. For example, the base plate 12 may be provided with a step to which the flange 22 of the inner cover 2 fits. A guide post may be provided upright on the outer periphery of the base plate 12, and a hole may also be formed in the flange 22 of the inner cover 2, and the guide post may be inserted through the hole to hang it down.

Second Embodiment A second embodiment of the present invention will be described with reference to FIGS. 4 and 5. FIG. 4 is a detailed cross-sectional view in this embodiment of the same portion shown as the portion A in FIG. 1 above. Therefore, as in FIG. 2, 12 is a base plate, 14 is a sealing ring, and 22 is a flange of the inner cover. In this embodiment, the flange 22 has the same flange structure as the conventional one without a clamp hole.

An L-shaped clamp arm 51 is implanted at a position slightly outside the flange 22 of the inner cover of the base plate 12, and the lower end of the clamp arm 51 is connected to the swivel cylinder 52. In the middle between the cylinder base 53 to which the swivel cylinder 52 is attached and the base plate 12, there is a set of two slide blocks 55, 55 'that combine inclined surfaces. One slide block, the upper one in FIG. The object 55 is movable in the left and right directions in this figure, and is connected to the clamp cylinder 54. The remaining lower block 55 'is fixed integrally with the cylinder base 53. An oil-free bush 56 is fitted in a portion of the cylinder base 53 where the axis of the clamp arm 51 penetrates.

FIG. 5 is a plan view of this portion. Initially, the clamp arm 51 is in the position shown by the alternate long and short dash line in this figure. When the flange 22 of the inner cover is placed on the base plate 12, the swiveling cylinder 52 is operated to rotate the clamp arm 51 in the direction of the arrow to the position indicated by the solid line. Next, the clamp cylinder 54 is operated to push the slide block 55 to the left in FIG. 4, whereby the cylinder base 53 is pushed downward, and at the same time, the tip of the clamp arm 51 pushes the flange 22 of the inner cover against the base plate 12. Therefore, as in the first embodiment, the seal ring 14 is crushed to achieve a reliable seal. The slide block and the clamp cylinder are omitted in FIG.

In this embodiment, since the flange 22 is not provided with the clamp hole as described above, it is possible to allow the deformation of the flange and the slight displacement in the mounting. In the above two embodiments, heat-resistant rubber seal rings are used as the heat-resistant seal members, but even if a groove is not formed in the base plate and a corresponding ceramic fiber sheet is inserted into the entire flange surface. Good.

[0019]

[Effect of the device]

 According to the present invention, even if the flange portion is slightly deformed, it can be mechanically clamped so that the seal is reliable, the quality problem due to the leakage of the atmospheric gas is eliminated, and the atmospheric gas This has the excellent effect of reducing the cost and maintenance cost of the inner cover.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a heat treatment furnace according to the present invention.

FIG. 2 is an enlarged cross-sectional view of a portion A in FIG. 1 showing the first embodiment.

FIG. 3 is an enlarged plan view of a portion A in FIG. 1 showing the first embodiment.

FIG. 4 is an enlarged cross-sectional view of a portion A in FIG. 1 showing a second embodiment.

FIG. 5 is an enlarged plan view of a portion A in FIG. 1 showing a second embodiment.

[Explanation of symbols]

 C coil 11 base 12 base plate 14 seal ring 2 inner cover 22 flange 23 clamp hole 3 furnace body 4 clamp mechanism 41 clamp head 42, 54 clamp cylinder 44 swivel motor 51 clamp arm 52 swivel cylinder 55, 55 'slide block

Claims (1)

[Scope of utility model registration request] 1. An atmosphere gas sealing device for a heat treatment furnace, which seals a space between an inner cover filled with atmospheric gas and containing a material to be treated and a combustion chamber formed outside the inner cover, A base plate of the heat treatment furnace which is made of metal and has a flat shape, and an inner cover having a flange mounted on the base plate,
An atmosphere gas sealing device for a heat treatment furnace, comprising: a heat-resistant sealing member inserted into a contact portion between the base plate and a flange of the inner cover; and a clamp unit that mechanically presses the flange of the inner cover against the base plate.