CONTINUOUS HOT ROLLING EQUIPMENT FOR THIN SCALE STEEL SHEET AND MANUFACTURE OF THIN SCALE STEEL SHEET

摘要

PURPOSE: To thin the thickness of scale by controlling cooling length and jet pressure in accordance with the surface temp. and the thickness of scale of a strip. ;CONSTITUTION: After the strip 1 of common steel, stainless steel, high Cr steel, etc., for example, which is finishing hot-rolled into about 1-25.4mm in thickness is made to travel to the down-stream side without loading, scales are removed with a descaling device 21 having jet pressure of ≥l00kg/cm² in the range the inlet and outlet sides of which are covered with pinch rolls 5 for descaling. After that, the strip 1 is cooled while passing through several stages of rapid cooling units 3 having the heat transfer rate of ≥4000kcal/mm².hr.°C. At this time, the necessary number of stage of the cooling unit is the measured values of a scale thickness detector 53 and coiling thermometer 47 on the downstream side of the cooling device from which the necessary descaling jet pressure and surface temp. drop of the strip are subtracted is calculated with an arithmetic unit 48 and, by controlling the descaling jet pressure, the strip is cooled to the coiling temp. of 450-650°C and a thin scale steel sheet is manufactured.;COPYRIGHT: (C)1996,JPO