JPH0241680B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for sealing a perforated part such as a metallurgical furnace exhaust gas flue or ore transportation piping.

Conventionally, metallurgical furnace exhaust gas usually contains SO ₂ , and in this case, metal parts such as flues corrode and form holes, or ore and coal transport pipes, etc., become worn out and form holes. This not only increases the amount of exhaust gas due to leakage with the air, but also reduces the temperature around the leakage point and promotes corrosion due to SO ₂ .
There were drawbacks such as exhaust gas leaking and polluting the environment.

The sealing method for repairing the above-mentioned holes is generally to attach a sealing material by welding, etc. However, for example, in the flue leading to a back filter, welding sparks can cause problems such as burnout of the back filter, and ore Because the ore and other materials could catch fire in transportation equipment such as welding equipment, operations had to be temporarily stopped before welding work could be carried out.

Furthermore, even in areas where welding sparks are not a problem, such as in boilers and electrostatic precipitators, welding work is extremely difficult in areas where the draft is negative because the molten metal from the welding rod is sucked in.

There is also a method of attaching a sealant to the hole using adhesive tape or commercially available adhesive, but this method
It had the disadvantage that it was not durable in areas where the temperature exceeded 100 degrees Celsius, such as on the outside of a boiler, and would fail within a few days.

The present invention has been made in view of the above-mentioned circumstances, and it is an object of the present invention to simplify the sealing method for repairing a hole, and to provide a sealing method for a hole that has good sealing performance and durability. The method for sealing holes in metal equipment such as metallurgical furnace flues involves mixing metal oxide powder such as bone ash or silica sand with alumina powder, which has a smaller particle size, in a ratio of approximately 1:1 by weight. It is characterized in that a sealing material of the same or different quality as the perforated metal part is adhered to the perforated metal part using a gel-like adhesive mixed with water glass such as sodium silicate. With this configuration, the adhesive is a mixture of metal oxide powder, water glass, and alumina powder with a small particle size, and can withstand high temperatures and has durability against SO ₂ .

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In the figure, 1 is a flue, and 2 is a perforated part. To clean the perforated part 2, first polish the adhesive bonded part 2a of the perforated part 2 of the flue 1 and one side of the sealing material 3 smooth, and then apply the adhesive to this polished surface. Paste it.

Here, as the adhesive, a mixture of metal oxide powder such as bone ash or silica sand and alumina powder is kneaded into a gel with sodium silicate (water glass).

In addition, the above adhesive contains finely powdered alumina, which has a smaller diameter than the metal oxide powder, at a weight ratio of at most 2 times or less, preferably approximately 1:1 to the metal oxide powder.
When mixed with , the adhesive strength becomes even stronger. However, even if it is mixed in twice or more, the adhesive strength will not change and it is uneconomical.

Further, the particle size of the alumina powder is preferably smaller than that of the metal oxide powder, and it is not necessary to use alumina, but an oxide powder having a somewhat high melting point may be used.

Therefore, according to various experimental results according to the present invention, it is best to mix alumina powder at a ratio of 1:1.

Experimental examples according to the present invention will be described in detail below.

<Example> Commercially available silica sand (SiO ₂ 84.2% Al ₂ O ₃ 12.5
% average particle size 10 μm) and alumina ultrafine powder (Al ₂ O ₃ 99.6%, average particle size 20 μm) were mixed in a 1:1 ratio, and water glass (sodium silicate) was added to this until it became hard and sticky. The mixture was used as an adhesive.

When the above adhesive was applied and sealed on the perforated parts of a boiler or electrostatic precipitator with a surface temperature of 300 to 400 degrees Celsius, and on the polished surface of the sealing material, the adhesive strength was strong.
Moreover, the durability has been further improved, and it has been confirmed that the tape can last for more than 6 months in places where conventional cloth adhesive tapes and commercially available adhesives would last only 4 to 5 days.

As explained in detail above, according to the method of sealing a hole according to the present invention, it does not require time and effort such as welding work, and there is no fear of igniting ore, etc., so it can be repaired in a short time. be.

Further, there is no need to stop operation during sealing work, and the work can be done easily and inexpensively, and has good durability.

[Brief explanation of drawings]

The attached drawings are explanatory diagrams of essential parts showing one embodiment of the present invention. 1... Flue, 2... Perforated area, 3... Sealing material.

Claims (1)

[Claims] 1. When sealing perforated parts of metal equipment such as metallurgical furnace flues, metal oxide powder such as bone ash or silica sand and alumina powder with a smaller particle size are mixed into approximately 1
A hole characterized in that a sealing material of the same or different quality as the perforated metal part is pasted using a gel-like adhesive mixed with water glass such as sodium silicate at a weight ratio of 1:1. How to seal open areas.