引进型300MW机组易发振动故障的诊断处理方法

本文总结了上海引进型300MW汽轮发电机组轴系的组成、各个轴承的型式以及此种汽机目前在山东省的投运状况。重点介绍了该型机组的易发异常振动的8种故障,如低压转子不平衡、发电机励磁电机三支承转子不平衡、发电机转子热不平衡、低发对轮螺栓松动、低发对轮连接螺栓护板撕裂脱落、发电机励磁电机对轮螺栓紧力不足、励磁机轴晃动大、发电机密封瓦碰磨、副励磁机动静碰磨以及7号可倾轴瓦柱销磨损碎裂等。在分析总结调试及大小修该型机组异常振动的故障过程中,给出了各个故障形成原因、机理、表现、以及各个故障的最佳处理方法。最后提出该型机组低压转子4号轴承异常振动、发电机转子的热态不平衡、发电机励磁电机三支承平衡、励磁机7号轴承振动的处理方法,以及在机组大修及运行中应注意的问题。

Diagnosis of Frequent Abnormal Vibrations in an Introduced Type 300MW Unit and Treatment Suggestions

This paper presents eight kinds of frequent abnormal vibrations in the introduced Shanghai 300MW turbine generator based on a close examination of its configuration,the patterns of the each bearing and current operation in the Shandong province.These abnormal vibrations include unbalance of the low pressure rotor,unbalance of the three bearings of the excitation electric motor,the thermo-unbalance of the generator rotor,the loosen of the screw bolts,the avulsion and break off in shaft coupling of low pressure generator,the lack tightness of screw bolts of excitation generator,the large shake of the shaft of the excitation generator,the collision and abrasion in the airproof tiles,the collision and abrasion in moving and rest of the vice excitation generator,the collision and smash of the cylindrical peg in No.7 tiltable tiles.For each abnormal vibration,the potential causes and characteristics are presented and the best methods to deal with each vibration are suggested based on the analysis and summarization of breakdowns encountered in the phases of adjustment and maintenance.This paper also proposes some methods to handle the abnormal vibration in bearings in No.4 low pressure rotor,the thermo-unbalance of rotor of the generator,the unbalance of the three bearings of the excitation electromotor and the vibration of No.7 bearing of the excitation generator,and highlights some potential problems in the large-scale maintenance and operations involving such a unit.