宝钢LPG船用低温钢板的开发

Development of low temperature steel plate for liquefied petroleum gas ships in Baosteel

介绍了宝钢研制开发的液化石油气(LPG)船用低温钢,从成分设计、微观组织控制、轧制工艺等方面介绍了LPG船用低温钢的生产实践,此外对试制钢板的拉伸性能、低温冲击韧性、NDT性能、CTOD性能及焊接性能进行了检测和分析。研究结果表明,研制开发的LTFH40、LT-FH32低温钢板,在满足自身强度级别要求的基础上,具有良好的低温冲击韧性,-75℃冲击功在250 J以上,且韧脆转变温度低于-120℃。此外,研制钢板具有良好的CTOD性能和NDT性能,表明钢板具有良好的抗起裂能力和止裂能力。采用埋弧焊接工艺对研制低温钢板进行焊接性能分析,结果表明,钢板焊接接头具有优异的强韧性能,-75℃焊接HAZ冲击功在200 J以上。最大厚度40 mm的LPG船用低温钢已顺利通过了ABS、BV、CCS、DNV、LR、NK、KR等七家船级社认证,实现大批量商业化应用。

Development of low temperature steel plate for liquefied petroleum gas（ LPG） ships in Baosteel was introduced,including the production practice of composition design,microstructure control,rolling technology and so on for low temperature steel. In addition,the tensile properties,low temperature impact toughness,NDT properties,CTOD properties and welding properties of developed steel plate were tested and analyzed. The results show that,the developed steel plate has excellent tensile strength and low temperature impact toughness,the impact energy is above 250 J at-75 ℃,and the toughening and brittle transition temperature is lower than-120 ℃. The developed steel plate have excellent CTOD performance and NDT performance,which shows that the steel plate has excellent cracking resistance and crack arrest ability. The welded performance of low temperature steel plate is evaluated by submerged arc welding process. The results show that the welded joint has excellent strength and low temperature toughness,and the impact energy of HAZ is over 200 J at-75 ℃. The40 mm thick LPG low temperature steel plate has successfully passed the ABS,BV,CCS,DNV GL,LR,NK,KR classification societies certification,and mass commercial production has been realized.