600MW超临界汽轮机高中压缸联合启动问题分析及处理

Analysis and Treatment of 600MW Supercritical Steam Turbine Startup through Combination of HP Cylinder with IP Cylinder

对600 MW超临界汽轮机高中压缸联合启动调试过程中出现的高压缸排汽温度高、上下缸温差大、低压差胀大几个问题进行了分析、研究,采取了合理调配旁路、强制通风阀以及各调门;合理选择轴封蒸汽参数;适当控制再热蒸汽温度、凝汽器真空等措施,使问题得以解决。提示了汽轮机启动时应在合理的寿命损耗范围内平稳升速、带负荷,才能预防差胀超限、缸体温差超限等异常情况的发生。

Problems in the commissioning process of 600MW supercritical steam turbine startup through combination of HP cylinder with IP cylinder, such as large temperature difference of upper and lower cylinders, high exhaust temperature of HP cylinder and differential expansion of LP cylinder, are analyzed and researched. These problems are solved by reasonably adjusting bypass valve, forced ventilation valve and other valves, selecting steam parameters of shaft seal, controlling temperature of reheat steam and vacuum of condenser, and so on. It is mentioned that to avoid abnormal status such as out-of-limit differential expansion, temperature difference of cylinder etc., the speed and load of steam turbine should be increased steadily within a reasonable life loss range during the startup process.