JPH03113287A - High temperature processing continuous furnace - Google Patents

Abstract

PURPOSE:To make it possible to lower the generation rate of accidents, reduce the cost of materials, eliminate limitations in the length of furnace and design a larger width of furnace by laying out a lower weight carriage and a hearth roll to the bottom in a low temperature zone. CONSTITUTION:Making the most use of a prior art roller hearth furnace's feature that the carrier speed of products can be variable freely, this invention makes it possible to reduce the probability of accidents due to the fact that a hearth roll 6, which is the negative side of the furnace, drives in a hot temper ature zone and eliminate the need to consider the thermal protection of the roll. Therefore, it is possible to adopt a longer roll length and a larger furnace width compared with the prior art roller hearth furnace. Since each transfer carriage 4 is carried the rotation of each hearth roller 6, there will be no restric tion about the length of furnace, which can be often observed among pusher furnace and the like. Furthermore, it is possible to select carrier speed freely, which makes it possible to change the time when processed substances can remain in a preset temperature zone. It is, therefore, possible to obtain a larger degree of freedom to design the length of furnace in a constant preset tempera ture zone and hence set an arbitrary temperature curve freely.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention provides a mobile cart constructed of a heat insulating material such as fiber,
The present invention relates to a continuous furnace for high-temperature processing in which cart driving means such as hearth rolls, which were conventionally driven in a high-temperature atmosphere, are placed in a low-temperature region.

[Conventional technology]

A pusher furnace that performs high-temperature treatment by directly loading the material to be treated on a plurality of plywood sheets laid out in a row and pushing the plywood; the material to be treated is mounted on a cart with a pulley, and the cart Typical continuous furnaces include a bogie furnace in which only the product moves within the high-temperature furnace with the product protruding from the top, and a roller hearth furnace in which the workpiece mounted on a tray is rotated and moved on a hearth roll built into the high-temperature furnace. The product has different characteristics in its transportation method.

[Problem that the invention seeks to solve]

The above-mentioned butcher furnace shown in FIG. 3(A) does not use pulleys and moves the plywood (9) by sliding it on the hearth surface.
9) is subject to severe wear and tear, making it easy for accidents to occur.In addition, dust from the wear between the plywood (9) on the sliding surface and the hearth surface accumulates in the furnace, making it difficult to remove and making work difficult. This is one of the causes of decreased efficiency.

In addition, the phenomenon of rising up between adjacent plywood panels (9) frequently occurs, and when an accident such as the rising phenomenon occurs, during repair, process management such as time loss as it is dismantled from the outside of the furnace and repaired. There is a lot of waste.

In addition, there is a drawback that the furnace length cannot be made long in order to suppress the above-mentioned uplift/upheaval phenomenon, and the upper limit is 30 to 40 m, and the conveyance speed is not sufficient, and the upper limit is about 3 m/Hr.

The object to be processed (1
) in the high-temperature furnace, the bogie furnace shown in Figure 3 (B) is
Due to its open structure, there are problems with atmosphere sealing.
In addition to poor thermal efficiency, the equipment is large-scale due to the large number of large carts (10) placed inside the furnace, and at the same time, compared to other furnaces, the foundation work is time-consuming, so high costs are unavoidable. A trolley with a pulley that protrudes outside (l O
) drive noise also poses an environmental health problem.

Furthermore, since the carts (10) are continuously conveyed, it is impossible to freely control the speed of each cart (10).

The roller hearth furnace shown in FIG. 3(C) has a structure in which the workpiece (1) mounted on a tray (11) is rotated on a hearth roll (6) built into the high-temperature furnace. 6) There are concerns about high-temperature reliability, and the roll length must be designed short to suppress deformation such as settling, and the use of expensive heat-resistant materials such as ceramics as the roll material is unavoidable. Due to the strength and durability of the hearth roll (6), the treated material tank i! There are problems such as not being able to take enough amount.

[Means for solving problems]

In order to solve the above-mentioned problems, in the present invention, a processing material loading plate is fixed to a movable trolley made of lightweight heat insulating material with a support, and the clearance between the movable trolley and the furnace wall is narrowed to create an over-sealed state. We have developed a continuous furnace for high-temperature processing in which the drive means for driving the movable trolley is arranged in a low-temperature region by blocking the heat of the high-temperature processing section at the top of the support with the upper surface of the movable trolley.

The driving means in the present invention is preferably a hearth roll or a metal mesh belt conveyor.

That is, a processing material loading plate (2) on which the product (1) shown in FIG. By making the space between the insulated moving cart (4) and the furnace wall (7) as narrow as possible and blocking the heat generated from the high-temperature heating element (5) at the top of the insulating moving cart (4), the hearth Roll (6
) is built into the furnace, by keeping the temperature atmosphere near the hearth roll (6) low, it combines the characteristics of a conventional bogie furnace, which is easy to transport, and the advantages of a roller hearth furnace. Hearth roll (6
) is a continuous furnace for high-temperature processing that solves the various problems that arise from being placed in a high-temperature state.

[Function and Examples]

FIG. 1 is a front sectional view in the advancing direction of a continuous furnace for high temperature treatment of the present invention, and FIG. 2 is a side view in the advancing direction.

As shown in Figure 1, the product loading plate (2) is embedded and fixed in a convex mobile trolley (4) made of lightweight fiber insulation material by means of four pillars (3) that support the product loading plate (2). A heating element (5) is arranged to create a high temperature atmosphere of 1000 to 1500°C.

I32 board (2) with supporting structures such as pillars (3) or supporting walls
The lightweight structure fixed to the trolley (4) is effective in improving the durability of the high-temperature treatment furnace.

The space within the furnace wall (7) may be sufficient to prevent the product (1) from rubbing against the furnace wall in the moving part of the processed material (1), but the space below the top surface of the convex moving cart (4) may be sufficient. The space between the furnace wall (7) and the convex movable trolley (4) is narrowed by narrowing the combined clearance of the unevenness to create an over-sealed state from the upper surface of the convex movable trolley (4) to the lower part of the convex movable trolley (4), thereby making it possible to block the heat generated by the heating element (5). Structure.

Fiber heat insulating materials are less restricted by measures to prevent abrasion damage, and by taking advantage of the design freedom of the uneven clearance structure, it is possible to form an uneven surface with a high sealing effect and to make the clearance sufficiently narrow.

With the above configuration, the mobile trolley (4) and the lower casing (8)
The temperature near the hearth roll (6) rotating through the
Forms a low temperature range of 00 to 250℃, conventionally 1000 to 1
Hearth rolls (6
) can be used in a milder temperature atmosphere.

Therefore, in this embodiment, as the material of the hearth roll (6), it is possible to use an iron roll, which is significantly cheaper and more versatile than the conventional expensive ceramic roll. The iron roll can be used not only with steel but also with cast iron.

The continuous furnace for high-temperature processing of the present invention has the above-mentioned configuration, which is different from the conventional method shown in Fig. 3 (C
) While taking advantage of the features of the roller hearth furnace shown in ), it is possible to reduce the probability of accidents caused by the hearth roll being driven in a high temperature range, which was its downside, and it also takes into account the heat resistance of the roll. Since this is not necessary, the roll length can be increased, and the width inside the furnace can also be increased compared to conventional roller hearth furnaces.

Since each movable cart (4) shown in Figure 2 is conveyed by the rotation of each hearth roll, there is no longer a restriction on furnace length as seen in pusher furnaces, etc., and since the conveyance speed can be freely selected, the set temperature range Since the residence time of the processed material can be changed, there is a large degree of freedom in designing the furnace length within a certain set temperature range, and the temperature curve can be set arbitrarily.

In addition, due to the over-sealed structure, the sealing performance inside the furnace is high, and the atmosphere 02% is less than 0.006%, compared to less than 0.02% in conventional roller hearth furnaces and less than 0.5% in bogie furnaces. shows a remarkable degree of sealing.

The accident rate that is inevitable with this type of continuous reactor is also kept low.
Furthermore, even if an accident occurs, there is no need for large-scale repair work such as dismantling the reactor, unlike other reactors, and maintenance and management can be simplified.

In other furnaces, it is essential to use brick as the heat insulating material used inside the furnace, but in the continuous furnace for high-temperature treatment of the present invention, it is possible to construct it with fiber, and an energy-saving effect can also be expected.

Table 1 shows a comparison of characteristics between the continuous furnace for high temperature treatment of the present invention and other conventional furnaces.

In Table 1 below (1) Continuous furnace for high temperature treatment of the present invention (2) Conventional pusher furnace (3) Conventional bogie furnace (4) Conventional roller hearth furnace The unit of conveyance speed is (m/Hr).

Table 1 From Table 1, the continuous furnace for high temperature treatment of the present invention is extremely advantageous overall.

〔Effect of the invention〕

The continuous furnace for high-temperature processing of the present invention reduces the incidence of accidents by arranging the hearth roll in the bottom low-temperature area along with a lightweight truck, reduces the cost of materials, and eliminates the conventional furnace length limitation. It has characteristics that greatly exceed conventional continuous furnaces, such as the ability to design a large furnace width, excellent atmosphere sealing properties, easy equipment maintenance and management, and energy savings due to the use of fibers.

In this specification, a hearth roll is used as the driving means, but the same effect can be obtained by using a metal mesh belt instead of the hearth roll.

[Brief explanation of drawings]

FIG. 1 is a front sectional view in the advancing direction of a continuous furnace for high temperature treatment according to an embodiment of the present invention, and FIG. 2 is a side view in the advancing direction, with the front side wall omitted. Figure 3 (A) (B
) and (C) respectively show a conventional pusher furnace, bogie furnace, and roller hearth furnace. (1) (2) (3) (4) (5) (6) Processed material (product) Processed material loading plate Support moving trolley Heating element Hearth roll Furnace wall casing Base plate 0) Trolley 1) Tray (7) ( 8) (9) (l (1

Claims (1)

[Claims] In a continuous furnace that moves and processes objects in a high-temperature atmosphere, a heat insulating material is provided between a moving cart and a processing material loading plate that are fixed to each other by a support structure, and the clearance between the moving cart and the furnace wall is maintained. For high-temperature processing, the driving means for driving the movable trolley is disposed in a low-temperature region by narrowing the space to create a near-sealed state and blocking the heat of the high-temperature processing section on the upper surface of the movable trolley with the upper surface of the movable trolley. Continuous furnace.