Iron runner spray-repair in thermal condition solution

The main sluice lining is not uniformly eroded during use, and some local damage, flaking, cracking, etc. will occur in the later stages of use. Especially in the main iron tapping groove of the iron storage, the direct impact of the molten iron poured from the tapping port makes the lining erosion depth of the part reach 200mm or more, causing the molten iron to stay, resulting in damage to the bottom lining of the iron tap. Exhausted. Or it is a deep pit or excessively wide crack in the trench. At this time, the main tapping lining cannot be used continuously due to local damage. If the tapping is stopped and the mold is poured again, the undamaged castable will be wasted, and unnecessary economic losses will be caused to the steel enterprise. The iron ditch spray material developed by our company can perform hot spray replenishment on the partially damaged main tapping ditch, which can make the tapping ditch perform the next tapping operation after a short time of spraying work, thus improving the main The service life of the iron ditches reduces the maintenance cost and reduces the economic losses caused to the steel enterprises due to the long or excessive maintenance time of the main tapping ditch. This method can also be used as a solution for the main iron trench repair.

Solution advantages:

1.    Superior product performance: The blast furnace tapping spray material developed by our company has the characteristics of high adhesion rate, strong adhesion, erosion resistance, erosion resistance and good thermal shock resistance.

2.     Scientific ratio: The spray material is similar to the iron groove castable, so the thermal expansion characteristics of the two are similar, which can prevent the peeling phenomenon caused by the difference in thermal expansion coefficient. Moreover, it has similar chemical characteristics to the iron groove castable, which can prevent the material from reacting at high temperature to form a low-melting phase.

3.    Fast construction speed: For the repair of the bottom groove and groove crack of the main tapping groove of about 16m, use about 4 to 5 tons of spray material, the thickness of the spray layer is about 200mm, and it takes 1 to 2 hours to carry out.

4.    High construction quality: The feeding speed, water addition and wind pressure can be controlled conveniently and accurately by the spray equipment, so that the spray material can be stably sprayed, the rebound rate is low, and at the same time it can be hardened quickly, eventually forming a uniform, a dense coating layer with a certain thickness.

5.    Easy construction: Compared with the lower mold casting, the spray method only needs about one-fifth of the labor, saving labor, and because the mold is not needed, the construction is faster, more convenient and safer.

6.    High economic efficiency: Compared with the nesting, since only partial spraying is required, the entire length of repair is not required, so that the amount of single-time refractory can be saved, thereby saving costs. At the same time, due to the short construction time, it can reduce the economic losses caused by the steel mills to stop the ditch and improve their economic benefits.

Main construction techniques:

At present, there are two forms of spraying on the lining of the tapping ditch:

(1)  Total spray method

For the main vulnerable parts, take a planned preventive comprehensive spray to achieve a balanced damage. In this case, care should be taken to adjust the life cycle of the iron trench. Or the main iron hook may appear in multiple places or extensive damage, and can be fully sprayed. The total amount of spray material used in the full spray method is large, and the service life of the iron lining can be greatly improved, and the spray time can be greatly shortened and the work intensity can be reduced.

(2) Partial spray method

When the slag line, iron wire, etc. in the main iron lining are partially damaged due to cracks, flaking, erosion, etc., the parts are sprayed and repaired, and the partial spray method is adopted. This method can be repaired with a smaller amount of spray material, so that the overall loss of the iron lining is balanced, it can also adjust the life cycle of the iron groove, which can greatly improve its service life and reduce it. Refractory unit consumption and unit cost reduction.

In addition, the thermal spray can also perform emergency spray repair on the local cracks and spalling of the iron lining to prevent iron leakage accidents caused by these damages.

In short, different types of spraying measures can be selected according to the damage of the iron lining and the construction conditions.

Main construction process of iron runner thermal condition spray:

1.    Plug the iron mouth, then release the residual iron of the main ditch as soon as possible, and then immediately re-block the residual iron mouth after the release.

2.     After the residual iron is discharged, immediately sprinkle the water to lower the temperature of the main ditch, then use the excavator to simply clean the slag on both sides of the main ditch. After cleaning, use the air compression tube to blow off the scum on both sides of the main iron ditch and the bottom.

3.    Start the spray preparation with the sprayer prepared in advance, and use the high-pressure spray gun to spray the mixture of spray and water to the damaged part. When spraying, repeat the spray from the end of the damaged part to the other end. The thickness reaches 15-20 cm, and the place with severe erosion can be determined according to the specific situation. Generally, 3-5 tons of spray material is needed for spraying, and the time is about 1 hour.

4.    After the spray is completed, the iron can be discharged in 20-30 minutes. If there is a thick part, the wood can be baked.