大直徑厚壁X70QS鋼級管線用無縫鋼管的在線熱處理工藝研究

Study on On-line Heat Treatment Process for Large-sized Heavy-wall X70QS Seamless Linepipe

摘要: 介紹了大直徑厚壁X70QS鋼級管線用無縫鋼管的化學成分及在線淬火熱處理工藝，對比分析了在線淬火和離線淬火對X70QS鋼級管線用無縫鋼管組織與性能的影響。分析認為：采用軋制后的再加熱+定徑在線淬火熱處理工藝，使得X70QS鋼級管線用無縫鋼管的表層和心部均獲得針狀鐵素體組織，其強度、韌性和耐蝕性能優(yōu)良。

Abstract: Briefly described here in the paper are the chemical composition of and on-line heat treatment process for the large-sized，heavy-wall X70QS seamless linepipe.Also comparatively analyzed are the effects on the said pipe’s structures and properties by the on-line quench process and the off-line quench process separately.The analysis leads to such a conclusion that thanks to employment of the on-line quench treatment process following postrolling reheating+sizing，the said pipe possesses acicular ferrite structures both in its outer layer and core area，which brings about excellent strength，toughness and corrosion resistance.