全管体正火热处理大直径直缝埋弧焊管的开发  

Development of Full-length Normalization Process for Large-sized SAWL Pipe

作　　者：谢仕强[1] 孙磊磊[1] 王波[1] XIE Shiqiang;SUN Leilei;WANG Bo(Baoshan Iron&Steel Co.,Ltd.,Shanghai 201900,China)

机构地区：[1]宝山钢铁股份有限公司,上海201900

出　　处：《钢管》2020年第4期9-13,共5页Steel Pipe

摘　　要：介绍全管体正火热处理L290N直缝埋弧焊管的开发实践。对热机械轧制管线钢钢板经UO制管后进行全管体正火热处理时容易出现拉伸屈服强度降低和钢管变形等问题进行研究。研究表明:采用C-Mn-微Nb成分系的L290N管线钢,在TMCP轧制后,获得铁素体和珠光体两相组织,具有明显的拉伸屈服平台,正火热处理后拉伸屈服强度明显降低,但依然保持明显的屈服平台,1.0%以内的冷变形率进行冷整形基本不影响拉伸性能。通过工程实践,批量生产了全管体正火热处理Ф711 mm×15.88 mm和Ф914 mm×17.48 mm规格L290N直缝埋弧焊管,其力学性能和几何尺寸均满足GB/T9711-2017标准及客户要求。Described here in the essay are the development activities associated with the full-length normalization process for the large-sized L290N SAWL pipe.Also studied are the problems of commonly-caused weakening of elongation yield strength and tube deformation as staying with the tube that is subjected to the full-length normalization treatment after being UO-formed into a tube from the linepipe-purposed steel plate as mechanically-hot rolled.The study result reveals that after TMCP rolled,the L290N linepipe-purposed steel of the C-Mn-micro Nb composition system develops both the ferrite and the pearlite 2-phase structures,having obvious elongation yield strength platform which still remains after the elongation yield strength is remarkably reduced due to the normalization treatment;and the elongation property is barely effected by the cold-shaping process with the cold deformation rate no more than 1.0%.With relevant engineering practice,the Ф711 mm×15.88mm and Ф914 mm×17.48mm full-length normalized L290N SAWL pipes are massively produced with all the indexes concerning the mechanical properties and geometric dimensions up to the GB/T 9711-2017 Standard and relevant customer requirements.

关 键 词：直缝埋弧焊管 L290N钢级 TMCP钢板 正火热处理 屈服强度 

分 类 号：TG162.84[金属学及工艺—热处理]