Of producing hot-rolled steel sheet for steel pipe excellent in hydrogen-organic cracking property

摘要

The present invention relates to a method of manufacturing a hot-rolled steel sheet for use in a crude steel and a natural gas-hydrogen steel sheet, and in particular, to provide a method for manufacturing a hot-rolled steel sheet for steel pipes having excellent hydrogen-;The present invention relates to a composition comprising C: 0. Si: not more than 0.010%, S: not more than 0.005%, Nb: not more than 0.050%, V: not more than 0.010%, Cu: not more than 0.20%, Ni: not more than 0.20, Ca: , The remainder Fe and other inevitably contained impurities is subjected to Ca treatment, slab casting and hot rolling in the usual manner, followed by hot rolling at a temperature in the range of 550-620 [deg.] C, And a method for manufacturing a hot-rolled steel sheet for a steel pipe excellent in characteristics.