JPS6028644Y2 - Melting furnace electrode - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrode for a melting furnace, which is used for direct current heating of glass, for example.

Tin oxide electrodes are particularly useful as electrodes for direct current heating of glass containing lead oxide, as they have less reducing properties than molybdenum or graphite electrodes, and there is no need to worry about depositing metallic lead.
It is commonly used.

However, tin oxide electrodes are extremely expensive and, moreover, are susceptible to corrosion due to their high temperatures, which is one of the causes of increasing the running costs of melting furnaces.

Tin oxide is 800'C! Below that, the electrical conductivity will drop sharply, leading to increased heat generation in the electrode portion, ie, power loss.

Therefore, a silver foil is inserted and brought into contact with the tin oxide until the temperature reaches 900° C. or higher, and electricity is applied to the tin oxide from an external power source through this silver plate.

This silver plate has a melting point of 960.5°C and cannot withstand the high temperature inside the furnace, which reaches 1500°C. Therefore, the parts that come into contact with the melt and the high temperature area where the temperature exceeds the melting point of silver are made of tin oxide. In other words, it plays the role of

Since the tin oxide electrode is exposed to the high pressure of the glass melt in the furnace, it is extended sufficiently to the outside of the furnace, and its end (which is exposed to the outside air and is at about 200 to 400 degrees Celsius) is strengthened by another means. must be maintained.

Therefore, tin oxide electrodes whose tips that come into contact with the melt are eroded and shortened cannot be reused and are disposed of as is, which is currently contrary to the recent social demand for resource conservation.

In particular, tin ore is an imported product, which poses problems from a national policy perspective.

It is therefore an object of the present invention to provide a tin oxide saving electrode.

According to research by the present inventors, the temperature of tin oxide is soo'c
The inventors discovered that tin oxide does not need to be used to conduct electricity from a silver plate because the electrical conductivity of the lower part rapidly decreases, and the present invention was developed.

In other words, the present invention provides an electrode for a melting furnace made by bundling a plurality of columnar tin oxides, and provides a boundary surface in a region where the temperature is about 800 to 900°C when the electrode is installed in the melting furnace.
The tin oxide electrode outside this boundary surface is replaced with a columnar refractory brick having the same cross-sectional shape, and a silver plate is brought into contact with a portion of the remaining tin oxide and sandwiched between the columnar refractory bricks. To provide an electrode characterized in that electricity is applied to tin oxide from the outside through a silver plate.

Next, the present invention will be specifically explained by examples with reference to the drawings.

Figure 1 is a perspective view, and the height is 5c1n as shown in Figure 1.
Three columnar tin oxide sintered blocks 1 each having a width of 10 cm and a length of 12.5 cm are lined up, and then
cmX width 10C? L rectangle) with length 12.5C
For example, JIS standard product 5K-38 of FIE refractory brick 2
, 36° 32, etc., and then, as shown in Fig. 2, silver plates 3 each having a thickness of 0.477+77EX (width 10 pieces) and a length of 21 cm (about 4.5 cm
Place it on top of each refractory brick so that the rectangular sides of cm are in contact.

The thus obtained units shown in Fig. 2 are stacked in three layers, and a unit made of tin oxide blocks and refractory bricks as shown in Fig. 1 is placed on the top layer. Get the electrodes.

A partial cross-sectional view of the glass melting furnace equipped with this electrode is shown in Figure 3.
As shown in the figure.

Number 4 is the furnace wall, 5 is the metal aluminum block, 6 is the nut, metal aluminum block 5
And bolts 7 are passed through the silver plate 3, and they are tightened with 6.

8 is a copper plate which is a terminal plate for conducting electricity from an external power source to the silver plate 3, and 9 is a cord for the external power source.

10.11 is a fireproof insulation brick for supporting the electrode of the present invention.

When the electrode of the present invention is installed in a melting furnace, the interface between the tin oxide block and the refractory brick is located near the outside of the furnace wall.

The position of this boundary surface is within the range where the temperature of the tin oxide electrode reaches 800 to 900° C. when the melting furnace is actually used.

Refractory bricks are not limited to those that have the same cross-sectional shape as the tin oxide block shown in Figure 1, but can also be made by combining several blocks into a single individual as shown in Figure 4. , or may be subdivided as shown in FIG.

According to the present invention, expensive tin oxide can be saved by about 40% compared to the conventional method, and even short tin oxide sintered blocks can be used, so that glass manufacturing costs can be reduced and resources can be increased.

[Brief explanation of the drawing]

1 and 2 are perspective views showing a partial structure of an electrode according to an embodiment of the present invention. FIG. 3 is a sectional view of a furnace equipped with the electrode of the present invention. 4 and 5 are perspective views showing partial structures of electrodes according to other embodiments of the present invention. Explanation of the symbols of the main parts: 1... Tin oxide sintered block, 2... Firebrick, 3... Silver plate, 4... Furnace wall.

Claims (1)

[Scope of utility model registration request] In a melting furnace electrode made of a plurality of columnar tin oxide bundles, the temperature is approximately 800 to 900°C when the electrode is installed in the melting furnace.
A boundary surface is provided in the area where the temperature reaches An electrode for a melting furnace, characterized in that the electrode is sandwiched between the columnar refractory bricks, and electricity is applied to the tin oxide from the outside through the silver plate.