The purpose of the present invention is to provide a high-tension hot rolled steel sheet which does not undergo local buckling when formed into a steel pipe and deformed by bending, shows excellent deformation characteristics after being formed into a pipe, and is appropriately usable as line pipes and oil well tubes.The constitution of the present invention is a composition comprising, in mass%, 0.04-0.08% of C, not more than 0.50% of Si, 0.8-2.2% of Mn, not more than 0.02% of P, not more than 0.006% of S, not more than 0.1% of Al, not more than 0.008% of N, 0.05-0.8% of Cr, 0.01-0.08% of Nb, 0.001-0.12% of V, and 0.005-0.04% of Ti, wherein the contents of Nb, V and Ti are controlled so as to satisfy a definite requirement, with the balance made up of Fe and unavoidable impurities, characterized in that a surface layer has a structure comprising bainite as a primary phase, 0.5-4% by volume of martensite as a secondary phase, and not more than 10% by volume in total of one or more members selected from among a ferrite phase, pearlite and cementite as a tertiary phase.
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