JPH0663705B2 - Cylindrical batch type firing furnace sheath - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a sheath for a cylindrical batch type firing furnace in which a cylindrical furnace body is arranged in a vertical direction.

(Prior Art) Generally, in a cylindrical batch type firing furnace, as shown in FIG. 5, a cylindrical furnace body 1 is vertically arranged, and a circular hearth 2 of the furnace body 1 is covered with Burned material (not shown)
The fired pods 3 for accommodating are placed radially with respect to the center of the hearth 2 and are stacked in a vertical direction in multiple stages, and U-shaped heaters 4 such as molybdenum silisite are placed at equal angular intervals on the outer periphery thereof. However, with these heaters 4,
It has a structure for firing an object to be fired housed in the sheath 3. When firing an object to be fired in a specific gas atmosphere, a predetermined gas is introduced into the inside of the furnace body 1 through pores 5 provided in the furnace wall forming the furnace body 1, and the object to be fired is Exhaust gas generated in the firing process is discharged to the outside of the furnace body 1 through an exhaust pipe 6 provided at the center of the furnace body 1.

In the cylindrical batch type firing furnace described above, as a sheath used for accommodating an object to be fired, conventionally, as shown in FIG. 6, there is provided a rectangular flat plate-shaped sheath 3a. It has been used that the sidewalls 3b and 3c are raised from both sides in the longitudinal direction of 3a and the lateral cross section is U-shaped.

By the way, in the cylindrical batch type firing furnace, if the pod 3 having the quadrangular pod 3a as described above is used,
A fan-shaped space S is formed between the pods 3 arranged adjacently on the hearth 2, and the atmospheric gas and the exhaust gas introduced into the furnace body 1 are retained in the space S. Therefore, the gas atmosphere in the furnace body 1 becomes non-uniform, heat conduction by convection is difficult to be performed, and the heat conduction to the sheath 3 is mainly performed by heat radiation, so that the temperature distribution in the furnace body 1 is also non-uniform. become. Also,
The space S between the pods 3 arranged adjacently on the hearth 2 is a dead space that does not contribute to the firing of the object to be fired, and the processing capacity of the cylindrical batch type firing furnace is reduced.

(Object of the Invention) An object of the present invention is to provide a cylindrical batch type baking furnace sheath with a high space productivity in which the temperature variation inside the furnace body is small and the object to be baked can be baked in a uniform gas atmosphere. Is to provide.

(Structure of the Invention) Therefore, the present invention has a fan shape having an inner arc portion having the same arc center and an outer arc portion and having an opening angle obtained by angularly dividing the hearth into almost equal parts. In addition to having a pod bottom, the pod bottom is provided with side walls that rise in the same direction on both sides, and is arranged in a circular shape on the hearth and the exhaust gas is exhausted through a circular hole formed in the center part above the hearth by an arc portion inside. Is characterized in that it is set to rise. That is, the present invention, by making the pod bottom shape fan-shaped, eliminates the space between adjacent pods, atmospheric gas flows from the outside to the inside of the pods arranged in a circle, and the generated exhaust gas is pods. The inner circular arc portion raises the inside of a circular hole formed in the central portion of the hearth.

(Effect of the Invention) According to the present invention, since the sheath bottom is fan-shaped so as to eliminate the space between adjacent sheaths, almost all the atmospheric gas supplied to the furnace body, from the outer circumference to the inner circumference of the sheath. The atmosphere gas inside the furnace body is homogenized as it passes through the inside, and heat conduction to the material to be fired is performed by both heat radiation and convection of the atmosphere gas, and the temperature distribution inside the furnace body is also The object to be fired that is homogenized and heat-treated at the same time is
There is little variation in quality and quality is good.

Further, according to the present invention, since the dead space between the adjacent pods is eliminated, the amount of the object to be fired is large, and it becomes possible to store a larger amount of the object to be fired in the furnace body and perform heat treatment. , The processing capacity of the furnace can be improved.

(Example) Hereinafter, an example of the present invention will be described with reference to the accompanying drawings.

The sheath 11 shown in FIG. 1 has a fan-shaped sheath 12 having an inner arc portion 12a having a radius r ₁ and an outer arc portion 12b having a radius r ₂ and having the same arc center P. sheath bottom 12 (r 2 _{-r 1)} of the side wall 13a that rises respectively the same orientation on both sides having a length, and a 13b.

As shown in FIG. 2, the fan-shaped pod bottom portion 12 has an opening angle θ which is an angle when the hearth 2 of the furnace body 1 is angularly equally divided around the center point Q. This opening angle θ is θ = 45 ° (= 360 ° / 8) in FIG.

The sheath 11 containing an object to be fired (not shown) is, for example, a cylindrical batch type firing furnace described in FIG. 5 together with other sheaths 11, 11, ... Having the same shape as shown in FIG. Around the center point Q of the hearth 2 of the
The side walls 13a and 13b of the 11, 11 are arranged so as to be in contact with each other, and a sheath 11 similar to the above is loaded on the side walls 13a, 13b close to the ceiling of the furnace body 1, as shown in FIG.

If the sheath 11 for the cylindrical batch type firing furnace is formed in the above-mentioned shape, the gas can pass from the outside of the sheath bottom 12 toward the inside in the radial direction as shown by an arrow A ₁ in FIG. Therefore, the atmospheric gas supplied from the pores 5 formed in the furnace wall of the furnace main body 1 into the furnace main body 1 was stacked in a columnar shape in multiple stages as indicated by an arrow A ₂ in FIG. It flows from the outside to the inside of the sheath 11 and is supplied to the object to be fired (not shown) housed in the sheath 11. Further, the exhaust gas generated from the material to be fired is indicated by an arrow A ₃ in FIG. 3 in the circular hole 14 formed in the substantially central portion on the hearth 2 by the sheath 11 stacked on the hearth 2 as described above. As shown, it rises and is discharged to the outside of the furnace body 1 through the exhaust pipe 6. As a result, the atmosphere gas is efficiently supplied to the object to be fired and the exhaust gas is discharged, the atmosphere gas is supplied to each object to be fired almost uniformly, and the convection of the atmosphere gas supplied to the inside of the furnace body 11 is performed. Also becomes better, and the temperature distribution inside the furnace body 11 is also made almost uniform. In addition, there is no dead space between adjacent pods, and the space productivity of the cylindrical batch type firing furnace is increased.

In the above-mentioned embodiment, as the material of the sheath 11, in addition to alumina, mullite, zirconia, etc., fiber board etc. can be used.

When a large number of pods 11 are stacked and used, or when the opening angle θ of the pods 11 is wide, as shown in FIG. 4, the arcs are formed in the arc center 12b outside the pod bottom 12 at the center. In order to prevent deformation of the portion 12b due to deterioration in hot strength, the side wall 13
It is preferable to provide the column 15 having the same height as the heights of a and 13b.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of the sheath for a cylindrical batch type firing furnace according to the present invention, and FIG. 2 is a cross section of the cylindrical batch type firing furnace showing the state in which the sheath of FIG. 1 is placed on the hearth. Fig. 3 is a sectional view taken along line IV-IV in Fig. 2, Fig. 4 is a perspective view of a modified example of the cylindrical batch-type firing furnace sheath of Fig. 1, and Fig. 5 is a conventional sheath. FIG. 6 is a cross-sectional view of a cylindrical batch-type firing furnace showing a state in which is placed on the hearth, and FIG. 1 …… furnace main body, 2 …… hearth, 11 …… sheath, 12 …… sheath bottom, 12a …… inner arc part, 12b …… outer arc part, 13a, 13b …… side wall, 14 …… circle Hole, 15 ... Support, S ... Space.

Claims (1)

[Claims] 1. A sheath for a batch-type firing furnace in which a to-be-sintered object is fired by being loaded on a hearth of a batch-type firing furnace in which a cylindrical furnace body is vertically arranged. There is an inner arc portion having the same arc center and an outer arc portion, and is provided with a fan-shaped pod bottom having an opening angle obtained by angularly dividing the hearth substantially equally, and this pod bottom Is equipped with side walls that rise in the same direction on both sides, so that the exhaust gas rises in a circular hole that is arranged in a circle on the hearth and is formed by the arc portion on the inside in the center of the hearth. Characteristic Cylindrical batch type firing furnace sheath.