JPS5945972A - Method of baking ceramic product - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for firing ceramic products that requires firing in a non-oxidizing atmosphere.

Conventionally, carbonaceous, silicon carbide mineral, ht2o3'-c system.

At2o, -c -stc system, C,1ILy -C
When firing ceramic products that require firing in a non-oxidizing atmosphere, such as ceramic products, the materials to be fired are housed in a Matsuful container made by a manufacturer built on a tunnel kiln or a single kiln trolley. After that, the gaps between the objects to be fired and between the objects to be fired and the wall of the Matsufuru container were filled with Bake C coke breath, and
The opening is sealed with refractory bricks and the material is transported into a furnace for firing.

However, the conventional two-way method has the following drawbacks.

(1) Because heat is conducted to the object to be fired through the Ill.j large Matsufuru container wall and the coke pleat, thermal efficiency is poor, and the temperature distribution within the container is uneven, causing potash and crystallinity within the container. I also miss the responsiveness.

I want to, (b) Fuel costs increase.

(B)! ! ! There will be variations in the quality of the product, especially in long products such as immersion nozzles and long stoppers, where there will be differences in physical properties depending on the part.

rl It is difficult to control the temperature during rising and descending (in particular, the only way to lower the temperature is through natural cooling (if you blow cooling air in the cooling zone inside the tunnel, the oxidation of the coke pleat will cause J
temperature A), it is not possible to control the temperature in one direction.

(b) It takes a long time (about 72 hours) to rise and fall, and even after unloading, it takes a long time (about 72 hours) for the temperature to drop to a point where it can be taken out of the kiln. Therefore, many carts are required.

(2) Matsuful containers constructed from refractories with a capacity of 1/4 inch are expensive, have a limited service life, and take a long time to construct. Moreover, work efficiency is poor because work can only be done from the top of the trolley.

(3) If a large amount of coke please is used, a large amount of cost is required, including compensation for the amount consumed. Moreover, even 1U coke has not yet achieved remarkable effects during loading and unloading from the kiln.

The present invention has been made to eliminate the above-mentioned drawbacks, and provides a method for firing ceramic products that improves product quality, significantly reduces costs, and improves work efficiency and work environment. This is what we are trying to provide.

All of the above-mentioned drawbacks are caused by the fact that the object to be fired is finally fired by covering it with coke pleat. Therefore, the present inventors investigated a method of creating a non-oxidizing atmosphere inside the Matsufuru container without covering the objects to be fired with coke pleat. It was discovered that it is sufficient to load fuel so that 1° of oxygen is removed. According to this method, since the Coke Please is not filled, the above-mentioned disadvantage (3) can of course be solved, and the temperature response inside the Matsufuru container is significantly improved, and the above-mentioned (
The disadvantage of 1) can be eliminated, and furthermore, the maintenance temperature of the firing zone of a tunnel kiln or the like can be significantly lowered.

Therefore, there is no need to use a refractory Matsufuru container, and a fully assembled Matsufuru container can be used, thereby solving the above-mentioned drawback (2). [Also 2, if a metal Matsufuru container is used, the temperature response will be further improved and the firing zone temperature can be further lowered.

'-J- That is, the method for firing a ceramic product of the present invention is a method for firing a ceramic product in which the object to be fired is fired in a non-oxidizing atmosphere, in which the object to be fired is housed in all the assembled containers, and the combustible material is not contained. It is characterized by being loaded and fired.

In the method of the present invention, the metal container has a lid and a door facing south,
It is desirable to use one whose top and side surfaces can be opened. Using such a metal container can improve work efficiency. -If the metal container has a double structure, it is possible to prevent the inner container from deforming due to heat.

However, in the method of the present invention, the combustible material loaded into the metal container may include pieces of wood.

An example in which the method of the present invention is applied to firing an alumina-carbon immersion nozzle will be described below with reference to FIG.

- First, a Matsufuru container made of steel plate (commercially available structural steel) as shown in FIG. 1 is prepared. This Matsufuru container is about 800
mm x 1000 mm x 1300 mm, one side and the top are open, and there are guides on the left and right sides.
a, a container body 1 provided with lb, a door 2, and a handle 3a
, 3b, and a lid 3 provided with some ventilation holes (not shown).

The vent provided in the lid 3 is designed to prevent pressure from increasing inside the Matsufuru container during baking.

Coke please 4 is always spread on the bottom of the container body 1 to a thickness of about 20 ounces, and is raked horizontally just before work. Next, after storing the wood chips (molded nozzle molded body) 5 in the container body 1, sufficiently dried wood chips with a low ash content are loaded.These wood chips have a temperature lower than the firing temperature. It burns at a high temperature, and the O in the container becomes CO□+CO, making the inside of the container a non-oxidizing atmosphere.

Subsequently, the door 2 is dropped along the id 1g'+1b of the container body 1, and the lid 3 is covered. Next, the Matsufuru container is placed on a trolley and carried into the furnace for firing.

1.7, the temperature inside and outside the Matsuful container during baking was measured, and the temperature response and temperature distribution inside the container were investigated. The measurement points were point A directly above the Matsuful container (height approximately 1300 mm from Taito), 8 points near the objects to be fired in the Matsuful container (approximately 800 mm apart), and point C near the objects to be baked in the Matsuful container ( p at three points with a distance of approximately 300 mm
) The relationship between the elapsed time in the furnace and the temperature difference between A-C and 11-0 is shown in the table below. In addition, the comparative examples in the table below use Matsufuru containers made of fireproof bricks.

Released after 55 hours? 1).

As is clear from the above table, the temperature difference between A and 0 is smaller in the actual bt example than in the comparative example, indicating that the temperature response is better. It can be seen that the temperature difference between 8 and 0 in the example is smaller than in the comparative example, indicating that the temperature distribution within the container is not so uneven. Still obtained alumina car+l?
It was confirmed that the quality of the submerged nozzle in the example was better.

Next, the cost effects and the like when using the method of the present invention will be explained.

(1) The amount of fuel used was 674,171 trucks in the conventional method, but 280,171 trucks were used in the method of the present invention, reducing fuel costs by about 58 points.

(2) The steel Matsufuru container used in the method of the present invention has a longer service life and is less expensive than the conventional refractory brick Matsufuru container, so the cost of the Matsufuru container can be reduced by approximately 86%.
It was also possible to reduce the゛It still has good temperature responsiveness (see the table above), and the work time can be reduced by 2/3, so the number of tables that need to be kept on hand can be significantly reduced, freeing up work space. . Fourth, in the conventional method, a high workbench was set up once a month and work could only be done from the top of the refractory brick Matsufuru container built on the negative mold, whereas as in the upper BI2 embodiment, work could only be done from the top and one side of the container. If you use a steel Matsufuru container that can be opened, a suitable IJ
Place it in place A: You can now work in a shielded position, and your work efficiency has improved significantly.

(3) The amount of coke pleat used in the method of the present invention is much smaller than that of the conventional method, and the cost of coke pleat can be reduced by about 80%. In addition, in the present invention, Coke please is not handled at all other than keeping it in the bottom of the container at all times.
The number of dust ponds is eliminated, the working environment can be improved, and the effect on occupational health is also significant.

(4) By reducing the above-mentioned fuel costs, pineful container costs, and coke please costs, the alumina car IJζ
The cost reduction per ton of product for the submerged nozzle is 111.9
1,000 yen, a reduction of 7:3.9%.

The method of the present invention can be applied to the following examples, as in the above embodiments.
Alumina car + carbonaceous ceramic products,
It can be applied to any ceramic product that requires firing in a non-oxidizing atmosphere, such as silicon carbide.

Further, as shown in FIG. 2, the outside of the container body 1 is connected to the outer container 6.
By covering the container body I with heat, deformation of the container body I can be prevented.

According to the present invention described in detail above, it is possible to provide a method for firing ceramic products that can improve product quality, significantly reduce costs, and improve work efficiency and work environment. .

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view showing a steel Matsufuru container according to an embodiment of the present invention, and FIG. 2 is a perspective view showing essential parts of the steel Matsufuru container with a double structure. 1... Container body, Ja, Jb... Guide, 2...
sin, 3...lid, 3a, 3t1...handle, 4...coke please, 5...object to be fired (immersion nozzle molded body), 6...outer container. 11:lFM! Patent attorney Suzue Takehiko:
Curvature r1 Diagram r2

Claims (3)

[Claims] (1) A method for firing a ceramic product in which the object to be fired is fired in a non-oxidizing atmosphere, characterized in that the object to be fired is housed in a metal container and a combustible material is charged and fired. Method. (2) A method for firing a ceramic product as described in item 1 of the patent application, characterized in that the metal container has a lid and a door, and the top and side surfaces can be opened. (3) A method for firing a ceramic product according to claim 1 or 2, characterized in that a metal stirrer having a double structure is used.