JPS5851912B2 - Spraying material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention particularly improves the adhesion rate and durability of spraying materials used for hot spraying repair of various refining furnaces such as converters and AOD furnaces, or for pouring construction of general kilns. The purpose is to provide spray materials.

In recent years, hot spray repair using dry or wet methods has been widely used in the converter steel manufacturing process, and has greatly contributed to extending the life of the lining, but the adhesion rate is generally between 75 and 80%.
However, the durability is about 3 to 4 cycles.

Therefore, not only is there a lot of waste (rebound loss) of the sprayed material, but also the durability is low, which increases the unit consumption, and the complicated spraying work has to be carried out again and again in an unsafe place, so it is especially important to improve the adhesion rate and the durability. There has been a strong desire to improve gender and solve these problems.

In response to this, the present inventors have been considering countermeasures for this problem, and the present inventors have proposed, for example, a magnesia-based refractory material with a cross-sectional diameter of 0.1 to 0.6M and a blade length of 10 to 0.6M. 5
Basic monolithic refractory for ladle lining containing 0.5 to 3.0% by weight of QII reinforcing bar (wire) (Japanese Patent Application Laid-Open No. 53-6341
We focused on the fact that slinker material (No. 4) exhibited good corrosion resistance as a slinker material, and as a result of further research, we found that thin metal wire or It has been discovered that by blending a small amount of fine ceramic fibers or both of them into a spraying material, it is possible to increase the tackiness, reduce splashing during spraying, and form a strong combustible layer, and the present invention has been made based on the present invention. was completed.

The present invention will be described in detail below based on examples.

As shown in Tables 1 and 2, the spray material of the present invention has the following properties:
In addition to the main components of refractory materials (aggregate and fine powder), metal wire or ceramic fiber coated with phosphate or the like using a conventional method is used as an outer layer with 0.
5 to 2.0 weight ratio is evenly blended, and if necessary, a small amount of a binder or the like is added.

For example, as shown in Table 1, a refractory material consisting of 400% by weight of fine powder of 6 to 20 meshes of MgO clinker aggregate, 6 to 48 meshes or more, and, if necessary, sodium phosphate powder as the original binder. 4.5% by weight (
In addition, 3.0% by weight (outer layer) of slaked lime fine powder is added as a viscosity modifier, and in addition, 1.0 weight percent (outer layer) of thin stainless steel wire whose surface has been coated with sodium hexametaphosphate is added. This is a spraying material that can particularly strengthen the adhesion during spraying to improve the adhesion rate, as well as form a stronger sintered layer and extend its durability.

In a solution of 60 parts by weight of sodium hexametaphosphate dissolved in 40 parts by weight of water, a diameter of 0.2B and a length of 30mm was added. A straight stainless steel wire of W was immersed and coated.

*2 A meandering steel wire with a diameter of 1.0 IK and a length of 455 m was immersed in a solution of 50 parts by weight of sodium silicate powder dissolved in 50 parts by weight of water and treated in the same manner.

*3 Tested after firing at 1200C for 2 hours according to JIS R2553 (Castaff) test method for strengthening refractories.

*4 ME installed in a test furnace with an ambient temperature of 1350℃
- After spraying on a panel made of Cr bricks with a well-known dry gun, the amount of adhesion (kg) was measured, and the initial gun injection amount *l *2 Manufactured in accordance with JIS R2553 test method for strengthening castable refractories. The samples were heated (fired) at 110° C. for 24 hours at 1000° C. for 3 hours, and then the bending strength at each temperature was measured.

*3 Calculated according to the adhesion rate *5 in Table 1.

*4 Daily inspection shows that the sprayed material is 3 times smaller than the original adhering area.
The state in which 0 or more coefficients remained was defined as the service life.

Incidentally, as the metal wire used in the product of the present invention, stainless steel or steel wire having a high melting point is generally used, and as the ceramic fiber, carbon fiber or silica-alumina type wire is used. Fiber or slag fiber can be used.

Metal wire and ceramic fiber (hereinafter referred to as
Wire, etc.) may be singular (single substance) or a combination of multiple wires.

The diameter is preferably 0.2 to 1.511 I, the length is preferably about 5 to 50 m, and there are various shapes such as straight, curved, and meandering.

If the diameter is less than 0.2n, it will be too thin and will deteriorate quickly due to the furnace heat, making it impossible to form a strong sintered layer, and if it is thicker than 1.5111, it will become somewhat flexible. The above range is preferable because it becomes difficult to clean and easily clogs at curved parts of spray hoses and the like.

In addition, the length should be 1/2 of the inner diameter of the hose to prevent blockage.
Although the degree is good, if it is less than 511, it is too short and cracks are likely to occur in the attached spray material (adhered layer), so slightly longer is better.

If the blending ratio is less than 0.5 weight ratio on the outside, the adhesion rate will not improve much, and if it is on a 20 weight plate, wires etc. may become tangled and unevenly distributed during storage, or clog in the pipe when spraying. Therefore, we limited it to a range of 0.5 to 2.0 weight factor.

There is no need for any special material (coating material) for pre-coating the wires, etc., and sodium hexametaphosphate, monobasic sodium phosphate, and pyrroline, which are conventionally added to spray materials as binders, can be used. A phosphate such as acid soda or a silicate such as sodium silicate or sodium metasilicate dissolved or diluted with water to an appropriate concentration is sufficient. After immersing it in the solution, it can be pulled up and dried, taking care not to form lumps.

Note that the corrosion resistance does not need to be very high.

As for the spraying material for soaking furnaces and the like, well-known treated silica-alumina fibers are used.

In addition to the above, there are many other fire-resistant materials suitable for the spray material of the present invention, such as dolomite, chromium, and high alumina, which can be crushed to the desired particle size and used in any proportion. As a binder, phosphate,
Silicates or other well-known materials may be added as appropriate, and bentonite or CM may be added as necessary.
A viscosity modifier such as C can be added.

These materials are kneaded using a conventional method, but it is convenient to add wires and other materials in small amounts continuously, rather than all at once, to mix them evenly in a short time. .

Next, the product of the present invention is hot-sprayed using a well-known dry gun, but the water added at the spray pipe removes the original binder such as sodium phosphate and the surface of the wire. Coating materials such as acid salts dissolve rapidly and exhibit strong adhesive strength.

Thus, while passing forward through the blowpipe at high speed, the refractory material is sufficiently wetted by the binder, and some of its aggregates and fines adhere in a thin layer to the surface of the wire and the like.

When the spray material hits the high-temperature damaged area from the nozzle at the tip, the wire acts as if it were a connector, making the fire-resistant material and the damaged area, or each other, stronger. Because they are connected and not separated,
Splashing is greatly reduced, and the adhesion rate is improved by about 5 to 10 times compared to the conventional method.

On the other hand, the adhered layer is immediately heated to a high temperature by the residual heat of the converter,
The added water begins to evaporate rapidly, but it is still being added.
- For example, all the water vapor that passes between the stainless steel wires is dissipated to the surface of the adhesion layer, so that large pores (cavities) are not created in the tissue.

When it is heated to a higher temperature during blowing, the sodium phosphate added as the original binder and the acid salt coating the surface of the stainless steel wire form a phosphate bond, causing the adhesion layer to deteriorate. Sintered even more strongly.

In addition, the shrinkage rate is very small, so there are almost no cracks, and the bending strength and corrosion resistance are improved, so it is resistant to mechanical shock when scrap is input, and eroded by slag, etc., and has a long lifespan. can be extended to about 1.5 times the conventional length.

As described in detail above, the spray material of the present invention can be made by blending a specific amount of metal wire or ceramic fiber whose surface is coated with a well-known coating material.
This is an excellent product with improved adhesion rate and durability.

Claims (1)

[Claims] 1. A metal wire and/or ceramic fiber whose surface was coated with phosphate and/or silicate was coated with an outer layer of 0.
A spray material characterized by containing a weight coefficient of 5 to 2.0.