Machine Fault Signature Analysis

Table 2

Some typical faults and defects that can be detected with vibration analysis.

Item	Fault
Gears	Tooth messing faults,
	misalignment,
	cracked and/or worm teeth,
	eccentric gear
Rotors and shaft	Unbalance
	Bent shaft
	Misalignment
	Eccentric journals
	Loose components
	Rubs
	Critical speed
	Cracked shaft
	Blade loss
	Blade resonance
Rolling element bearings	Pitting of race and ball/roller
	Spalling
	Other rolling elements defect
Journal bearing	Oil whirl
	Oval or barreled journal
	Journal/bearing rub
Flexible coupling	Misalignment
	Unbalance
Electrical machines	Unbalanced magnetic pulls
	Broken/damaged rotor bars
	Air gap geometry variations
	Structural and foundation faults
	Structural resonance
	Piping resonance
	Vortex shedding