An effective vacuum melting technique based on the improved vacuum degassing technique was used to produce thick-walled seamless pipes of 9Cr-1Mo-V-Nb-N martensitic heat resistant steels in order to reduce the content...An effective vacuum melting technique based on the improved vacuum degassing technique was used to produce thick-walled seamless pipes of 9Cr-1Mo-V-Nb-N martensitic heat resistant steels in order to reduce the contents of harmful impurity such as oxygen, phosphorus. Then the pipe was heat treated by using optimized process technique. Both static and dynamic mechanical properties at room temperature and 566℃ were measured respectively and evaluated by means of comprehensive analysis of standard deviation and statistic test. The results show that the comprehensive mechanical properties of this pipe are much better than those of pipes untreated with the improved vacuum degassing technique and heat-treated by using original heat-treatment process and almost the same as those of imported P91 thick-walled seamless steel pipe.展开更多
为弥补净空高度650 mm过小而溢溅频发的缺陷,以真空脱气的热力学和动力学为基础,分析了真空度、吹氩流量、保真空时间对VD脱气的影响,最终匹配了一套高效变量真空泵系统。经过细致调试,对真空系统运行制度、真空吹氩制度、精炼工艺等参...为弥补净空高度650 mm过小而溢溅频发的缺陷,以真空脱气的热力学和动力学为基础,分析了真空度、吹氩流量、保真空时间对VD脱气的影响,最终匹配了一套高效变量真空泵系统。经过细致调试,对真空系统运行制度、真空吹氩制度、精炼工艺等参数进行了优化。生产表明,新钢210 t VD精炼炉具有超大高效低能耗的优点,其性能达到了国际先进水平。展开更多
文摘An effective vacuum melting technique based on the improved vacuum degassing technique was used to produce thick-walled seamless pipes of 9Cr-1Mo-V-Nb-N martensitic heat resistant steels in order to reduce the contents of harmful impurity such as oxygen, phosphorus. Then the pipe was heat treated by using optimized process technique. Both static and dynamic mechanical properties at room temperature and 566℃ were measured respectively and evaluated by means of comprehensive analysis of standard deviation and statistic test. The results show that the comprehensive mechanical properties of this pipe are much better than those of pipes untreated with the improved vacuum degassing technique and heat-treated by using original heat-treatment process and almost the same as those of imported P91 thick-walled seamless steel pipe.
文摘为弥补净空高度650 mm过小而溢溅频发的缺陷,以真空脱气的热力学和动力学为基础,分析了真空度、吹氩流量、保真空时间对VD脱气的影响,最终匹配了一套高效变量真空泵系统。经过细致调试,对真空系统运行制度、真空吹氩制度、精炼工艺等参数进行了优化。生产表明,新钢210 t VD精炼炉具有超大高效低能耗的优点,其性能达到了国际先进水平。
