Study on Ultra Fast Cooling Technology in Hot Strip Mill

With advanced high-strength steels and high value-added steels development, it is very important to improve the cooling capacity and cooling intensity of the run out table cooling system. The key technology is to break the vapor between hot strip and cold water and to increase the direct contact area. In order to realize the ultra fast cooling, Laboratory research such as jet nozzle type selection and diameter of nozzle decision and factory tests such as cooling capacity testing have been done. Experiment results show that circular nozzle has bigger hitting power than fan-type nozzle. However, drainage capacity caused by fan-type nozzle is better than that by circular nozzle. In addition, nozzles of different diameters have nearly the same cooling capacity despite of the very different water flow. Cooling power testing results show that cooling capacity is enhanced with pressure increasing and with speed decreasing.