2013 Volume 99 Issue 11 Pages 635-641
Benefit of intensive water cooling before controlled rolling was introduced and laboratory tests were conducted with water flow rate of 0.10-0.17m3/m2s. Cooling performance was quantified in conditions of relatively higher surface temperature of 850-1100ºC. Temperature drop in specimen increases with higher water flow rate. Upper limit of cooling performance was not found in the range of experimental conditions. At higher surface temperature, where is more than 1000ºC, cooling performance at upper surface is much larger than at lower surface, whereas difference of cooling performance between upper surface and lower surface is small at lower temperature. Effect of transfer speed was not seen in cooling time of 0.2-0.3s. Based on experimental data and thermal analysis, equivalent heat transfer coefficient was calculated to be 10-29MW/m2 K, which is extremely higher than in literature data. As a result, it was clarified that repeat of short time intensive cooling inter pass is possible to realize effective production in controlled rolling.
