秦山第二核电厂发电机转子引线垫条断裂故障分析

摘要

介绍了核电QFSN-650-2型发电机转子端部的结构,基于转子解体情况及引线垫条断口分析,认为发电机转子旋转时引线垫条受到了垂直于垫条表面的往复疲劳应力以及离心力的作用.解体发现,固定引线垫条的各段槽楔松紧不一,引线垫条在引线槽楔接缝处因离心力产生了剪切应力,同时因垫条表面受损,应力集中,造成了引线垫条断裂.为防止引线垫条断裂,将其材质由OCr18Ni9不锈钢换为Q235碳素钢;为防止引线垫条断裂后造成事故,取消其垂直段,并在其水平段加装防松装置.对检修维护提出了建议,为同类故障的处理提供借鉴.%The structures of generator rotor lead-wires underlay pieces of nuclear power generator QFSN-650-2 were presented. The reason of the broken underlay pieces is deduced based on the rotor disassembly and the underlay pieces broken cross section inspection. The to-and-fro tired stress and centrifugal force on the underlay pieces with the rotating rotor caused the failure. The different fasten strength on the slot wedges resulted in the homologous cut stress on the underlay pieces with the slot wedges joints. On the same time, the stress concentration caused by underlay pieces surface damnification also contributed to the failure. To prevent the accident caused by underlay pieces broken, the material of the underlay pieces should be changed from 0Cr18Ni9 to Q235, the upright part of the underlay pieces should be cut off, and a tighten setting should be fixed in the horizontal part. Some suggestions are presented to prevent same malfunction and to facilitate the regular overhaul.