| 摘要 |
The present invention relates to a hot-rolled steel sheet for line pipe with good ultra low temperature thoughness having a composition consisting of C:0.04 to 0.07% by weight; Mn:1.50 to 1.65% by weight, Si:0.15 to 0.25% by weight, P:not more than 0.010% by weight, S:not more than 0.003% by weight, Nb:0.040 to 0.060% by weight, V:0.040 to 0.060% by weight, Ti:0.010 to 0.020% by weight, Mo:0.10 to 0.30% by weight, Ni:0.10 to 0.30% by weight and the reainder being Fe and unavoidable impurities. If the composition of steel slag is controled appropriately as in the present invention, the hot rolled steel for line pipe will have high strength, superior cryogenic impact toughness and prolonged life in transporting crude oils in the extreme environments. |
