METHOD FOR HOT ROLLING AND STEEL SHEET OF LINE PIPE MANUFACTURED USING THE SAME

摘要

Disclosed are a method for hot strip rolling and a steel sheet for a line pipe manufactured by the same method which is improved no less than 95% of wave front ductility at 0°C changing hot rolling conditions. The hot strip rolling method according to the present invention includes the following steps of: (a) roughening a slab lank containing no less than 0.04 weight% of niobium (Nb) at an inputting temperature of no lower than 900°C, and at an outputting temperature ranging from 800°C to 850°C for 100 to 150 seconds; and (b) finishing milling the roughened slab blank at an output temperature ranging from 750°C to 800°C. [Reference numerals] (AA) Invention steel