Cooling Ways of Seamless Steel Billet

According to the chemical composition of the seamless steel pipe, a state organization, product section size, deficiencies that may arise after cooling, and the rolling mill, cooling equipment, space and cooling conditions after hot rolling of steel can be used with different cooling methods to cool to room temperature.

1) Air-cooled
This is the natural air cooling method, it is applied very widely. After all the air is cooled, it is not a martensitic microstructure or steel, the use of air cooling after hot rolling, such as low carbon steel, low-alloy ordinary strength steel, most of the carbon steel and alloy semi-martensitic structure steel, and austenitic stainless steel, and are using this method of cooling.

2) Rapid cooling
It is blowing, spraying, water is forced through the cooling method of steel making process is characterized by a certain period drama cooled to a temperature in the cooled natural. Such as requiring testing carbide steel mesh defects using this cooling method. Carbon steel wire rod also rapid cooling after rolling, in order to improve the overall mechanical properties of the wire.

3) Slow cooling
It features after hot rolling steel slab or stack together to make it slowly cooled, to prevent white spot defects. The specific method of slow cooling according to the production conditions, and can be dedicated slow cooling pit, can be moved in a special slow cooling box to be stacked on the floor, cover with sand, slag and other asbestos insulation was subjected slow cooling. This cold

But approach applies to martensite, martensite and half Ledeburite type of steel, such as high speed tool steel, stainless steel, tool steel and high-alloy section high alloy structure, they produce stress upon cooling very sensitive strong.

4) Heat treatment
After the heat treatment method commonly used hot-rolled annealing, tempering, normalizing.