Seamless steel pipe, manufacturing method thereof and heavy oil thermal recovery sleeve

The invention provides a seamless steel pipe, a manufacturing method thereof and a heavy oil thermal recovery sleeve. The seamless steel pipe comprises, by weight, 0.20-0.30% of C, 0.20-0.60% of Si, 0.50-1.20% of Mn, 0-0.015% of P, 0-0.003% of S, 0.80-1.30% of Cr, 0.30-0.70% of Mo, 0.005-0.02% of Ti, 0-0.10% of Ni, 0.01-0.05% of Al and the balance Fe and inevitable impurities. According to the seamless steel pipe provided by the invention, the content of all the elements is adjusted comprehensively, so that the strength of the seamless steel pipe is greatly improved, meanwhile, the seamless steel pipe has high toughness, thus, large-amplitude tension-compression stress changed frequently can be effectively resisted, and the seamless steel pipe can be applied to high-strength heavy oil thermal recovery better. 本发明提供了种无缝钢管、其制造方法及稠油热采套管。按重量百分含量计，无缝钢管包括：C 0.20～0.30％、Si 0.20～0.60％、Mn 0.50～1.20％、P≤0.015％、S≤0.003％、Cr 0.80～1.30％、Mo 0.30～0.70％、Ti 0.005～0.02％、Ni≤0.10％、Al 0.01～0.05％、余量为铁Fe和不可避免的杂质。本发明提供的无缝钢管，综合调整了各元素的含量