Hydraulic Unbalance in Oil Injected Twin Rotary Screw Compressor Vibration Analysis

Vibration analysis of screw compressors is one of the most challenging cases in preventive maintenance and this kind of equipment consider as one of the vibration bad actor facilities in industrial plants. on line condition monitoring systems develop too much in recent years for such equipment. The high frequency vibration of ball bearing, gears, male and female cause complex FFT and TWF in screw compressors. The male and females usually and randomly sending to balance shop for balancing operation and it usually cause some bending in rotors during the balancing operation that cause further machining in such equipment. These kind of machining operation increasing the vibration analysis complexity of such equipment beside some process characteristic abnormality like inlet and out let pressure and temperature. In this paper first I briefly explain mechanical principal and different type of screw compressors beside this I tried to explain some new condition monitoring system and techniques of such equipment. Finally I discusses one of the common behavior of oil injected twin rotary screw compressor called hydraulic unbalance usually occur after machining operation of male or female and have some specific characteristics in FFT and TWF. Hope this paper will helpful for the readers to achieve better understanding of rotary screw compressor vibration analysis in real industrial process conditions.