摘要
Abstract
The cold cracking sensitivity and fracture characteristics of XI00 pipeline steel HAZ were studied by using submerged-arc welding and implant test. The result indicated that in the case of no preheating, X100 pipeline steel is insensitive to cold cracking, the critical fracture stress cra is 823.5 Mpa, which is equivalent to the tensile strength Rm (823 MP), so steel can be welded without preheating. When the constraint stress increases continuously, the aging fracture occurs, the fracture characteristics is typical hydrogen induced crack. The reason for high resistance to cold cracking of X100 pipeline steel is mainly due to Ceq (Pcm) forO. 21%, HAZ hardening is not obvious. The structure of overheated zone is granular B+F, the maximum hardness value is 266HV)0, which is lower than the critical hardness value of 35OHV1O. Furthermore, the f100 is lager, and the time of hydrogen escape is much long during submerged-arc welding process. The sinter can isolate air, and CaF2 can eliminate hydrogen, so that the electric arc can be combustion in low hydrogen.关键词
X100管线钢/埋弧焊管/插销试验/冷裂纹敏感性Key words
XI00 pipeline steel/submerged-arc welded pipe/ implant test/cold cracking sensitivity分类
矿业与冶金
