JPH08151276A - Spray material composition - Google Patents

Abstract

PURPOSE: To obtain a spray-type repairing material for repairing a converter, pot for molten steel, etc., while it is hot, free from flow even on a vertical wall, having high adhesiveness and excellent in endurance. CONSTITUTION: This spray-type repairing material composition is obtained by compounding 100 pts.wt. of a basic refractory material with 2-6 pts.wt. of an urea resin or a melamine resin and 4-10 pts.wt. of a pitch having a softening point of >=150 deg.C. The composition is further mixed with clay in the range of <=5wt.%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a spray material for hot repairing a converter or a molten steel ladle.

[0002]

2. Description of the Related Art Spraying materials used for hot repair of converters and molten steel pots have often used phosphoric acid type binders, but spraying materials using phosphoric acid type binders have slag. When it penetrates, it has a drawback that it forms a low-melting point compound and melts, and its durability is limited. As a solution,
There is a method of adding carbonaceous material, but a repair material using an organic binder such as pitch or phenol resin is proposed for the purpose of more aggressively forming carbon bonds, expressing strength and preventing penetration of slag. Has been done.

The use of the pitch and the phenol resin alone has been pointed out to have problems in softening, flow, smoke generation, etc.
As an improvement, an amorphous refractory material in which pitch and a phenol resin are used in combination is used (for example, JP-A-60-235772).

[0004]

The spray material used as a hot repair material is, of course, important in terms of durability, and in terms of workability, reliable adhesion to a repair surface, especially on a vertical wall. Sex is required. However, since the phenol resin and the pitch added in the form of powder are once softened and then hardened, there is a problem that the sprayed repair material flows down and it is difficult to accurately repair the target site. That is, in the conventional combination of only organic binders, the addition amount thereof is limited and the slag penetration preventing effect is not sufficiently exerted. Further, a method of using an inorganic binder in combination for the purpose of suppressing the initial flow-down has also been proposed, but the addition of an inorganic binder that leads to a decrease in fire resistance has a drawback that the advantages of an organic binder cannot be fully utilized. Therefore, when used as a spray repair material, it is desired to develop a spray repair material having a shape-retaining ability immediately after spraying only with an organic binder.

[0005]

DISCLOSURE OF THE INVENTION The inventors of the present invention have studied the binder for suppressing the excessive softening flow in the initial stage, and as a result, found that the problem can be solved by using a urea resin or a melamine resin. Has been completed. That is, the present invention is based on 100 parts by weight of the basic refractory material, 2 to 6 parts by weight of urea resin or melamine resin, and softening point.
This is a spraying material composition consisting of 4 to 10 parts by weight of a pitch having a temperature of 150 ° C. or higher, to which clay is added in an amount of 5 parts by weight or less.

As the basic refractory material used in the present invention, known refractory materials such as magnesia, calcia, magcalcia, dolomite and magnesia-alumina spinel can be used alone or in combination. Also,
In the present invention, a carbon material from the viewpoint of preventing slag penetration,
One or two of non-oxides such as silicon carbide and silicon nitride
It is also possible to use two or more species together.

A feature of the present invention is to use a urea resin or a melamine resin, and these resins may be commercially available products. The amount used is 2 to 6 parts by weight with respect to 100 parts by weight of the basic refractory material. If the amount is less than 2 parts by weight, the adhesiveness of the repair material is poor. Is low, the construction body becomes porous and corrosion resistance decreases. The urea resin and the melamine resin can be mixed and used, and the phenol resin can be used together for the purpose of improving the strength of the construction body.

The pitch used in the present invention may be either petroleum-based or coal-based, but the one having a softening point of 150 ° C. or higher is used, and the amount used is 4 with respect to 100 parts by weight of the basic refractory material. -10 parts by weight. The softening point is set to 150 ° C. or higher in order to prevent the initial softening flow for the reason described below. Also, if the amount used is less than 4 parts by weight, carbon bond formation is insufficient and exceeds 10% by weight. And corrosion resistance decreases, which is not preferable.

In the present invention, it is possible to prevent the intended initial softening flow with the above constitution, but clay is further contained in the range of 5 parts by weight or less relative to 100 parts by weight of the basic refractory material. You can also The amount of this clay used is 5
If it exceeds the parts by weight, the corrosion resistance decreases.

The spray material composition of the present invention can be used in the same manner as an ordinary spray material, and can be directly applied to a general-purpose spray machine. The added water content is also the same as the conventional product.

[0011]

[Function] When the phenolic resin added to the repairing material is hot applied to the repaired part, if the repairing material is gradually heated and the temperature rises, even if the thermosetting phenolic resin is 50 to 150
After softening once at a temperature of ° C, hardening begins. At this time, the phenol resin flows, disperses and hardens in the construction body to develop the strength of the construction body, and also moves to the repair surface to develop adhesiveness, but since the construction body itself softens, it is vertical. When it is constructed on a wall, it will flow down from the target position,
Sufficient repair is impossible. However, if there is no softening flow to some extent, the adhesion to the repaired surface is reduced, causing peeling. This adjustment cannot be done sufficiently with phenolic resin. However, the urea resin and melamine resin used in the present invention have a very short softening time at a low temperature, the curing starts early, and the repair material adheres to the repair surface, so that the repair material can be prevented from flowing due to the softening flow.

The repair material that has reached the repair surface adheres to the repair location due to the hardening of the urea resin or melamine resin, and the temperature gradually rises. Then, the pitch begins to soften and begins to flow, but the entire repair material adheres to the repair surface due to the hardening of the urea resin or melamine resin, and since the shape retention is maintained, the entire repair material does not flow and the softened pitch Flowing between refractory materials,
It reaches the repair surface and is cured by the heat of the repair surface to form a carbon bond. As a result, stronger adhesiveness and strength of the repair material can be obtained. However, if the softening temperature of the pitch is too low at this time, the softening flow of the pitch is started before the urea resin or melamine resin is cured, which causes the repair material to flow down. Therefore, the softening temperature of the pitch needs to be higher than the temperature at which the resin begins to harden.

Furthermore, the addition of clay imparts moderate plasticity to the spray repair material, resulting in improved workability and initial adhesion.

[0014]

[Examples] The materials shown in Table 1 were repaired by spraying on the vertical wall of the trunnion part of the 300 ton converter at the A Works. Table 1 also shows the results of visual observation of the adhesion rate of the material after spraying and the number of times it was used.

[0015]

[Table 1]

As is clear from the results shown in Table 1, in comparison with the fact that the adhesion rate during spraying is extremely high,
When a conventional phenol resin was used, even if a pitch having a high softening point was used (Comparative Example 1), the adhesion rate remained low when sprayed on a vertical portion. In addition, even when the urea resin is used as in the present invention, when the pitch of the low softening point is used together (Comparative Example 2), the adhesion rate is slightly higher, but it does not reach the present invention, and as in the present invention, By using a urea resin or melamine resin in combination with a high softening point pitch, it has been shown that the adhesion rate becomes high. Further, also in terms of the number of times of service, the product of the present invention exhibits high service life. It is also found that the use of clay (bentonite) is effective in improving the adhesion rate (Example 2,
3).

[0017]

As described above, according to the present invention, by using the urea resin or the melamine resin in place of the conventional phenol resin, it is possible to prevent the sprayed repair material from softening and flowing on the repair surface and flowing down, and to achieve good adhesion. And then the action of the pitch provides stronger adhesion and improved durability due to carbon bond formation. Therefore, when a converter or a molten steel ladle is hot-repaired, it does not flow down even on a vertical wall, has high adhesiveness, and is an excellent spray material composition with high durability.

Front page continued (72) Inventor Shigeyuki Takanaga 433, Koto Nishi, Bizen City, Okayama Prefecture 27 (72) Inventor, Horikawa Ho 2 793, Uraibu, Bizen City, Okayama Prefecture

Claims (2)

[Claims] 1. A spraying material composition comprising 100 parts by weight of a basic refractory material, 2 to 6 parts by weight of a urea resin or melamine resin, and 4 to 10 parts by weight of a pitch having a softening point of 150 ° C. or higher. . 2. A urea resin or melamine resin 2 to 6 parts by weight, a pitch 4 to 10 parts by weight having a softening point of 150 ° C. or higher, and a clay 5 parts by weight or less based on 100 parts by weight of the basic refractory material. The spray material composition.