What Is Vibration Caused By ?

Imperfections in the Machine:

Design	Assembly
Manufacture	Operation
Installation	Maintenance

What Are Some Common Machine Problems
That Generate Mechanical Vibration:

Misalignment	Unbalance
Worn belts & pulleys	Bearing Defects
Hydraulic Forces	Aerodynamic Forces
Reaction Forces	Reciprocating Forces
Bent Shafts	Rubbing
Gear Problems	Housing Distortion
Certain Electrical Problems	Frictional Forces

What Are Some Common Machine Problems
That Amplify Mechanical Vibration (But Don't Cause It):

Resonance

Looseness