Ahmad alfakeer posted:
We have an issue high vibration on BRG #2&3 , finish the Major Inspection on this unit when we start the unit , at FSNL ( 3000 RPM ) the vibration for BRG # 2&3 stable not exceed (6 mm/s ) , when the unit is loaded the vibration increase on BRG 2&3 Only , at full load the Vibration reach on BRG # ( 9- 13 mm/s fluctuating ) and BRG #3 ( 7- 8.5 mm/s ) , and in the MI inspection we made casing Alignment as recommended from manufacturer GE because when open the unit we found the BRG # 2 is damage from Upper haif and BRG # 3 is damage on lower haif and there is oval on AFT compressor casing and before open unit the vibration on BRG # 2 reached ( up to 19mm/s ) , all bearing replaced BY new ones and the vibration still , please to advice me to know what is the cause of vibration .
note : all vibration on BRG # 4 & 5 are smooth not exceed (2mm/s )at Full load
thanks in advance
please to help me ???