焊材匹配与钢板合金成分对X80管线钢管低温韧性的影响

Influence of Welding Material Matching and Alloy Components on Low-temperature Toughness of X80 Linepipe

研究了不同焊材匹配对X80管线钢管焊缝低温(-45℃)冲击韧性的影响,优选出适用于低温直缝埋弧焊管焊接的焊材匹配方案;采用同种焊接工艺对两种不同合金体系的X80钢级管线钢管进行焊接,研究了不同合金成分对钢管DWTT性能、焊接热影响区低温冲击韧性的影响。研究结果表明:采用低S、P杂质的高碱度氟碱型烧结埋弧焊剂匹配Mn-Mo-Ti-B系埋弧焊丝可使焊缝获得优良的低温冲击韧性;在X80管线钢中适量添加Ni同时微调Si、Mo、Cu、Ti含量,可以有效改善母材低温DWTT性能和热影响区的低温冲击韧性。

Studied here in the paper is the influence on the low-temperature(-45℃)of the X80 linepipe by the different matching types of the welding material,based on which the prior matching scheme applicable to welding the SAWL pipe for low temperature service is determined.The X80 linepipes of two different alloy systems are welded with the same welding process for the purpose of studying the effects by different alloy components on the DWTT performance and the low-temperature impact toughness of the welding HAZ of the steel pipe.As a result,it is regarded that the matching of the Mn-Mo-Ti-B SAW welding wire with low S and P impurity and high alkalinity fluorine base type sintered SAW welding flux is capable of bring about low-temperature impact toughness.And the low temperature DWTT performance and HAZ low-temperature impact toughness of base metal can be improved by properly adding more Ni element,and meanwhile trimming the contents of Elements Si,Mo,Cu and Ti in the X80 line pipe steel.