Beginner's Guide to Machine Vibration
Revision 28/06/06
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Contents Foreword....................................................................... 1 Section 1: Why is Monitoring Vibration Important?.. 2 What is Machine Vibration? ..................................................... 3 What Causes Machine Vibration?............................................ 5 (a) Repeating Forces ...................................................................5 (b) Looseness ..............................................................................7 (c) Resonance..............................................................................8
Why Monitor Machine Vibration? ........................................... 10 (a) Severe Machine Damage .....................................................11 (b) High Power Consumption.....................................................12 (c) Machine Unavailability ..........................................................12 (d) Delayed Shipments ..............................................................13 (e) Accumulation of Unfinished Goods ......................................13 (f) Unnecessary Maintenance....................................................14 (g) Quality Problems ..................................................................14 (h) Bad Company Image............................................................15 (i) Occupational Hazards ...........................................................15
Summary ................................................................................ 16
Section 2: How is Machine Vibration Described? ... 17 How is Vibration Described?.................................................. 18 What is Amplitude? ................................................................ 19 What is Frequency? ............................................................... 22 What is A Waveform?............................................................. 23 What is A Spectrum?................