汽轮机安全监视系统信号突变故障分析及处理

Analysis and treatment of steam turbine monitoring system probe signal for mutation

针对某石化公司GB201压缩机组中汽轮机端轴位移和轴振动信号出现的突变现象,对汽轮机接地电刷、BENTLY3500接地系统及静电产生原因进行了研究。由于机组不能停机,先对可能导致故障的各相关因素进行了分析。排除可以排除的因素,在线检测及更换了汽轮机接地电刷、在线检测了BENTLY 3500接地系统及分析了转子带电或带磁的影响。最后判定润滑油受高速运转的转子与轴承挤压摩擦产生了静电,并且因轴承座较大而导致TSI探头的同轴接头在轴承座内,接头长期浸泡在50℃左右的润滑油里中,绝缘效果或变差,静电累积到同轴接头上,从而导致静电荷积聚及突变现象的产生。后在机组停机检修时,打开轴承座检查,对同轴接头重新做了绝缘处理,再次开机后恢复正常。研究结果表明,信号突变是由于润滑油高速运转的转子与轴承挤压摩擦产生静电及轴承箱内的TSI探头同轴接头绝缘失效。

Aiming at the Petrochemical Industries Co GB201 compressor unit,the shaft displacement and shaft vibration signal of the turbine side appeared mutation phenomenon,the grounding brush for steam turbine,the BENTLY 3500 grounding system and the static electricity causes were researched.The unit could not be stopped,only to analyse related factors which could lead to malfunction.Exclude factors could be excluded,the steam turbine grounding brush was inspected and replaced on-line,the BENTLY 3500 grounding system was inspected and the influence of rotor electric or magnetic was analysised.Finally,it was determined that the static electricity from the lube oil by high speed rotor and bearing extrusion friction,and the bearing house was too larger to the joint of the TSI probe in the bearing house,the joint was soaked in the lube oil which temperature is 50° for a long time,the insulation may become worse,the electrostatic was accumulated to the joint,resulted electric charge accumulation and mutation phenomenon.After the unit was overhaul,the bearing house was opend and inspected,the prode joints were isolated afresh,when the unit was running again it was back to normal.The results indicate that the signal mutation is because of the static electricity from the lube oil by high speed rotor and bearing extrusion friction and the insulation of the TSI probe＇s joint is failure.