Anti-carburizing construction process for casting cooling water pipe in blast furnace cooling wall

Abstract

The invention discloses an anti-carburizing construction process for casting a cooling water pipe in a blast furnace cooling wall, belonging to the technical field of the preparation of the metallurgical machinery. The invention provides an anti-carburizing construction process for casting the cooling water pipe in the blast furnace cooling wall without carburizing on the outer surface of the cooling water pipe and forming a carburizing layer. The anti-carburizing construction process comprises the following steps: bending the cooling water pipe, and derusting the bended cooling water pipe; then spraying an Al2O3 layer of which thickness is no more than 0.10-0.15mm on the outer surface of the cooling water pipe; then painting a water-based zircon powder paint layer of which thickness is no more than 0.2mm on the outer surface of the qualifiedly sprayed cooling water pipe, and drying; and finally embedding the cooling water pipe in a casting mould cavity, assembling the mould and casting the cooling wall, wherein the Al2O3 coating is directly formed through the chemical combination of the molten Al wire and oxygen in air during the spraying process.

Description

technical field [0001] The invention relates to an anti-carburization construction technology, in particular to an anti-carburization construction technology for casting cooling water pipes in a cooling wall of a blast furnace, and belongs to the technical field of metallurgical machinery manufacturing. Background technique [0002] The service life of staves used in metallurgical blast furnaces mainly depends on the anti-carburization effect of cooling water pipes. The carbon content of the existing stave is generally between 3.4% and 3.6%, while the material of the cooling water pipe is 20 steel, and its carbon content is between 0.15% and 0.25%. Surrounded by high-temperature molten iron, if there is no anti-carburization coating protection, the carbon in the molten iron will inevitably penetrate into the cooling water pipe, resulting in carbonization on the surface of the cooling water pipe, and the cooling water pipe after carbonization will lose its toughness. Under t...

AI Technical Summary

Problems solved by technology

For the stave produced by the above process, during casting, the high-temperature molten iron partially breaks through the water-based zircon powder coating and contacts the cooling water pipe, forming a local carburized layer on the outer surface of the cooling water pipe, and its carburized depth is generally 0.1-0.5 mm range, and the gap between the cast cooling water pipe and the stave body is ≥0.3mm, which will easily cause the cooling water pipe to break and the stave to seep, which will reduce the service life of the stave, increase the amount of equipment maintenance, and reduce the The normal production efficiency of the blast furnace affects the output of the blast furnace