THE COOLING PROCESS IN SPRAY OVERLAP DURING HYDRAULIC DESCALING

conference paper

en

The manufacturing of high quality steels is connected to high temperatures at which the material reacts with the surrounding atmosphere. A layer of iron oxides (scales) is formed on the surface of the steel. To ensure a high quality product, the layer must be removed prior to any metal forming operation. The mass production of steel requires a quick and effective method of descaling. In the overwhelming majority of cases, the descaling is performed by high pressure flat jet water nozzles placed in a row. This article builds on the previous texts on the process optimization and further studies the effect of the offset angle of the nozzles on the uniformity of the cooling impulse on the surface of the hot rolled steel strip. Current research has brought a significant improvement in the area of measurement of the heat transfer coefficient. The article compares two configurations of nozzles and presents the impact pressure measurements and corresponding heat transfer coefficient measurements for both of them. The results obtained so far show that the commonly used configuration is not optimal from a cooling point of view. The new suggested configuration presents a new method of making the cooling impulse and the cooling rate more uniform along the width of the hot rolled steel strip of the descaled surface.

The manufacturing of high quality steels is connected to high temperatures at which the material reacts with the surrounding atmosphere. A layer of iron oxides (scales) is formed on the surface of the steel. To ensure a high quality product, the layer must be removed prior to any metal forming operation. The mass production of steel requires a quick and effective method of descaling. In the overwhelming majority of cases, the descaling is performed by high pressure flat jet water nozzles placed in a row. This article builds on the previous texts on the process optimization and further studies the effect of the offset angle of the nozzles on the uniformity of the cooling impulse on the surface of the hot rolled steel strip. Current research has brought a significant improvement in the area of measurement of the heat transfer coefficient. The article compares two configurations of nozzles and presents the impact pressure measurements and corresponding heat transfer coefficient measurements for both of them. The results obtained so far show that the commonly used configuration is not optimal from a cooling point of view. The new suggested configuration presents a new method of making the cooling impulse and the cooling rate more uniform along the width of the hot rolled steel strip of the descaled surface.

hot rolling, descaling, heat transfer coefficient, scales

23.05.2018

Tanger, Ostrava

Ostrava

978-80-87294-83-3

Sborník konference METAL 2018

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