N135-13.24/535/535型机组低压末级叶片裂纹原因分析  

CAUSE ANALYSIS OF FRACTURES ON LOW-PRESSURE LAST-STAGE BLADES IN N135-13.24/535/535 UNITS

作　　者：常剑冰 秦东 冯文吉 秦鸿义 

机构地区：[1]河南电力试验研究院,河南郑州450052 [2]河南电力物资公司,河南郑州450052

出　　处：《热力发电》2009年第3期94-96,93,共4页Thermal Power Generation

摘　　要：对某台N135-13.24/535/535型机组2Cr12MoV钢低压末级叶片进汽边出现大量密集裂纹的原因进行了试验分析,结果表明,因强化工艺选用不当或控制不严,致使低压末级叶片进汽边表面强化区域完全淬透,形成硬化区,淬火相变组织应力较高,是叶片产生裂纹的主要原因。对此,建议制造厂对低压末级叶片局部高频淬火强化工艺进行完善,如采用激光处理等工艺,避免叶片裂纹的产生。Directing against the causes leading to a lot of concentrated fractures occurred on the low - pressure last - stage blades of 2Cr12MoV steel in N135 - 13.24/535/535 units,a test analysis has been carried out. Results of test show that the main cause is due to the reinforcement technolgical process of said blades having been unsuitably selected or unstrictly controlled,the reinforced zone at steam -inlet side of the low - pressure last - stage blades due to fully quenched, a hardened zone being formed, and having higher stress in the phase -changed structure. For this,it is recommended that the manufacturer should perfect the high frequency quenching process for partial dopting laser treatment etc. , so as to avoid occurrence of fractures on reinforcement of the said blades, such as athe blades.

关 键 词：汽轮机 2Cr12MoV钢 末级叶片 裂纹 高频淬火 强化 

分 类 号：TK263.3[动力工程及工程热物理—动力机械及工程] TG115[金属学及工艺—物理冶金]