JPH0510679A - Body insulating structure for batch type combustion furnace - Google Patents

Abstract

PURPOSE:To obtain a body insulating structure which can reduce both a heat radiation loss and temperature rising.cooling necessary times in a batch type combustion chamber. CONSTITUTION:A body insulating structure for a batch type combustion furnace comprises an insulating wall 10 in the furnace, made of heat insulating layers 4 superposed through air layers 11. A plurality of heat resistant pipes 12 disposed along a horizontal direction, are mounted in the layer 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a furnace body heat insulation structure of a batch type firing furnace used for firing a ceramic molded body.

[0002]

2. Description of the Related Art Conventionally, ceramic molded bodies have been used for forming electronic parts such as chip capacitors, and when firing these ceramic molded bodies, heat treatment of a small amount of a wide variety of articles is performed. It is common to use a suitable batch firing furnace. In such a batch type firing furnace, as shown in a simplified manner in FIGS. 3 and 4, a firing chamber 2 for heating and firing an object to be fired 1 such as a ceramic molded body, and an object to be fired 1 are fired. It is composed of a hearth 3 which is pushed up and stored in the chamber 2.

As a furnace body heat insulating structure surrounding the firing chamber 2, an in-furnace heat insulating wall 5 in which a plurality of heat insulating layers 4 made of heat insulating bricks or ceramic fiber boards are stacked on each other is used. The inner heat insulating wall 5 is attached to and supported by the furnace shell steel plate 6 via a stud bolt (not shown) made of a heat-resistant metal or the like. Although not shown, a heater for heating the object to be fired 1 by so-called radiative heat transfer is provided on the inner surface of the insulative wall 5 in the furnace, and the hearth 3 moves up and down such as a table lifter. It goes without saying that it is mounted on the moving mechanism.

[0004]

By the way, in the furnace body heat insulating structure of the batch type firing furnace having the above-mentioned conventional structure,
Since the in-furnace heat insulating wall 5 is formed by directly and entirely overlapping the plurality of heat insulating layers 4 with each other,
If the wall thickness of the heat insulating wall 5 in the furnace is increased in order to reduce the heat radiation loss, the amount of heat stored in the heat insulating wall 5 in the furnace increases, and the time required for heating and cooling is extended. When the wall thickness of the heat insulating wall 5 in the furnace is reduced in order to reduce the time required for heating / cooling, there is a contradictory inconvenience that the heat radiation loss increases.

The present invention was devised in view of such inconvenience, and provides a furnace body heat insulation structure for a batch type firing furnace which can reduce both heat radiation loss and required heating / cooling time. The purpose is to.

[0006]

In order to achieve such an object, a furnace body heat insulating structure of a batch type firing furnace according to the present invention has an in-furnace heat insulating wall composed of heat insulating layers stacked with an air layer in between. And a plurality of heat-resistant pipes arranged in the horizontal direction are attached in the air layer.

[0007]

According to the above construction, each of the air layers functions as a useful heat insulation layer, and the heat insulation performance of the in-furnace heat insulation wall is enhanced. As a result, the amount of heat that is stored in this furnace heat insulation wall is reduced.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional view showing a simplified furnace body heat insulating structure of a batch type firing furnace according to this embodiment, and FIG. 2 is a transverse sectional view taken along the line AA of FIG. In these figures, the same parts and portions as those in FIGS. 3 and 4 showing the conventional example are denoted by the same reference numerals.

This batch type firing furnace is provided with a firing chamber 2 for heating and firing an article 1 to be fired, such as a ceramic molded body.
And a hearth 3 for pushing up and storing the article to be fired 1 in the firing chamber 2, and the lower opening of the firing chamber 2 is placed on a lifting mechanism (not shown) to move up and down. The hearth 3 is closed. The firing chamber 2 is surrounded by an in-furnace heat insulating wall 10, and the in-furnace heat insulating wall 10 is composed of a plurality of heat insulating layers 4 that are superposed with an air layer 11 having a predetermined thickness interposed therebetween. Here, a material suitable for the temperature condition is selected for each heat insulating layer 4, and, for example, two ceramic fiber boards having a thickness of 20 mm are stacked and used.

Further, in each air layer 11, a plurality of heat-resistant pipes 12 which are spaced apart at predetermined positions along the vertical direction and are arranged along the horizontal direction are attached. Each end is fixedly supported by a furnace shell steel plate 6 provided so as to surround the heat insulating wall 10 in the furnace. Here, these heat-resistant pipes 1
2 serves to reinforce the heat insulating layer 4 while ensuring the inner dimension of the air layer 11. The reason why the inside of the air layer 11 is horizontally divided by these heat-resistant pipes 12 is to prevent up and down convection of air in the air layer 11, and the diameter is about 25 mm or less. It is desirable to attach the heat resistant pipes 12 at intervals of 100 to 200 mm. Further, here, the material of each heat resistant pipe 12 is selected according to the temperature condition,
Pipes made of heat-resistant metal in low temperature range (less than 1000 ℃),
A ceramic pipe made of alumina, mullite, or the like is used in a high temperature range (about 1000 ° C to 1400 ° C).

Although not shown, the heat insulation wall 10 in the furnace is attached to and supported by the furnace shell steel plate 6 through stud bolts made of ceramics such as alumina or heat resistant metal. A heater is provided on the inner surface for heating the material to be fired 1 by so-called radiative heat transfer. The material of this heater is also selected from molybdenum silisite, silicon carbide, metal, etc. according to the required temperature. Furthermore, in the above description, the respective end portions of the heat-resistant pipes 12 mounted in the air layer 11 are supported by the furnace shell steel plate 6, but, for example, the end portions of each heat-resistant pipe 12 are connected to the furnace shell steel plate. It may be projected to the outside of 6. That is, in this way, one end side thereof can be connected to an air blower (not shown) or the like. Is rapidly cooled, and the heat insulation wall 10 in the furnace is cooled.
Through this, there is an advantage that the cooling of the firing chamber 2 can be accelerated.

[0013]

As described above, according to the furnace body heat insulating structure of the batch type firing furnace according to the present invention, each of the air layers provided between the heat insulating layers forming the heat insulating wall in the furnace is a useful heat insulating layer. As a result, the heat insulation performance of the in-furnace heat insulating wall is enhanced, so that the amount of heat released to the outside through this in-furnace heat insulating wall is reduced and the amount of heat stored in this in-furnace heat insulating wall is reduced. As a result, there is an effect that both the heat radiation loss and the time required for heating / cooling can be reduced.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a simplified furnace body heat insulating structure of a batch type firing furnace according to the present embodiment.

FIG. 2 is a cross-sectional view taken along the line AA of FIG.

FIG. 3 is a simplified vertical sectional view showing a furnace body heat insulating structure of a batch type firing furnace according to a conventional example.

4 is a cross-sectional view taken along the line BB of FIG.

[Explanation of symbols]

 4 Heat-insulating layer 10 In-furnace heat-insulating wall 11 Air layer 12 Heat-resistant pipe

Claims (1)

Claim: What is claimed is: 1. An in-furnace heat insulating wall (10) comprising heat insulating layers (4) superposed with an air layer (11) interposed, wherein the air layer (11) is provided. A furnace body heat insulation structure for a batch type firing furnace, characterized in that a plurality of heat-resistant pipes (12) arranged along the horizontal direction are attached.