循环流化床锅炉用高温耐磨蚀热电偶保护套管

摘要

According to the failure mechanism of thermocouple protection tubes applied in circulating fluidized bed boiler, a new type of iron-based high temperature alloy and slender blind-hole tube casting technology was developed.Equilibrium microstnctures of the alloy at room temperature were austenite, a small amount of ferrite and carbide ceramic phases.The alloy possesses outstanding anti-erosion ability at 750 ℃.Slender blind-hole tubes were prepared with this alloy by special casting method and welded with common stainless steel pipes forming different specifications of thermocouple protection tubes.These tubes are widely used in circulating fluidized hed boiler and achieves good results.%针对热电偶保护套管在循环流化床锅炉中的失效机理,开发了新型铁基高温合金材料和细长盲管制备技术.该合金在室温下的平衡组织为奥氏体+少量铁素体+碳化物陶瓷相.在750℃表现出了优异的抗冲蚀性能.采用该合金制备出细长盲管,和不锈钢延长管焊接制备出不同规格的热电偶保护套管,在循环流化床锅炉上应用,取得了良好的效果.