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Training Course ManualOnVibration AnalysisLevel – 1March 25-28, 2019Organized byCentre for Vibration Analysis & Condition Monitoring (CVCM)Directorate of Nuclear Power Engineering Reactor (DNPER)PAKISTAN ATOMIC ENERGY COMMISSION
Table of ContentsTable of Contents . 2CHAPTER 11.1MAINTENANCE PHILOSOPHIES . 1A COMPARISON OF MAINTENANCE PHILOSOPHIES . 11.1.1Breakdown Maintenance . 11.1.2Scheduled or Preventive Maintenance . 11.1.3Predictive Maintenance . 11.1.4Proactive maintenance . 21.2 ADDITIONAL APPLICATIONS FOR VIBRATION DETECTION ANDANALYSIS . 21.1.1Incoming Inspection: . 21.1.2Machinery Acceptance Standards . 31.1.3Quality Control . 3CHAPTER 22.1CONDITION MONITORING . 5Vibration analysis . 52.1.1Online monitoring . 52.2Acoustic Emission (Ultrasound) . 62.3Infrared thermography. 62.4Oil analysis . 72.5Wear particle analysis . 82.6Motor testing . 8CHAPTER 3PRINCIPLES OF VIBRATION . 103.1CHARACTERISTICS OF VIBRATION . 103.2VIBRATION FREQUENCY . 113.3SIGNIFICANCE OF VIBRATION FREQUENCY . 123.4VIBRATION AMPLITUDE . 163.4.1VIBRATION DISPLACEMENT . 163.4.2VIBRATION VELOCITY . 213.4.3VIBRATION ACCELERATION . 233.5CONVERSION OF MEASUREMENT PARAMETERS . 253.6WHEN TO USE DISPLACEMENT, VELOCITY AND ACCELERATION . 263.7 WHEN TO USE DISPLACEMENT AS AN INDICATOR OF STRESSPROBLEMS . 263.8WHEN TO USE VIBRATION VELOCITY TO DETECT FATIGUE PROBLEMS273.9WHEN TO USE VIBRATION ACCELERATION TO DETECT FORCE
PROBLEMS . 273.10PHASE. 283.10.1SIGNIFICANCE OF PHASE . 293.10.2PHASE MEASUREMENT TECHNIQUES . 303.11INSTRUMENTS FOR VIBRATION DETECTION AND ANALYSIS. 313.11.1THE VIBRATION TRANSDUCER . 323.12THEORY OF OPERATION . 323.13WHAT ABOUT DISPLACEMENT AND VELOCITY MEASUREMENTS? . 333.14ACCELEROMETER FREQUENCY RANGE . 343.14.1GENERAL PURPOSE ACCELEROMETERS . 353.14.2PERMANENTLY MOUNTED ACCELEROMETERS . 353.14.3LOW FREQUENCY ACCELEROMETERS . 353.14.4HIGH FREQUENCY ACCELEROMETERS . 363.15IMPORTANCE OF ACCELEROMETER MOUNTING . 363.15.1STUD MOUNTING. 373.15.2ADHESIVE MOUNTING . 373.15.3MAGNETIC HOLDER . 373.16WHERE TO TAKE THE READINGS . 393.17VIBRATION FREQUENCY ANALYZERS . 403.17.1ANALOG (SWEPT-FILTER) FREQUENCY ANALYZERS . 403.17.2DIGITAL (FFT) FREQUENCY ANALYZERS. 413.18WHAT IS FFT? . 423.18.1DEFINING FFT SPECTRAL PARAMETERS . 423.18.2SELECTING FMAX . 433.18.3MACHINES WITH ROLLING ELEMENT BEARINGS . 433.18.4SLEEVE BEARING MACHINES . 443.18.5MACHINE WITH GEAR DRIVES . 453.19SELECTING THE NUMBER OF LINES OF RESOLUTION . 473.20UNDERSTANDING THE CURSOR FREQUENCY . 49CHAPTER 4TIME WAVEFORM ANALYSIS . 524.1WHAT IS A WAVEFORM? . 524.2WAVEFORM CHARACTERISTICS . 524.3AMPLITUDE . 534.4PERIODIC . 544.5COMPLEXITY . 54
4.6IMPACTS/SPIKES . 554.7DISCONTINUITIES . 554.8ASYMMETRY . 564.9LOW FREQUENCY EVENTS . 574.10ELECTRICAL VS MECHANICAL . 584.11WAVEFORM ANALYSIS AS CONFIRMATION . 594.12CASE HISTORY 1 . 604.12.14.13Vertical Turbine Pump Unbalance . 60CASE HISTORY 2 . 624.13.1Fan Bearing Looseness . 62CHAPTER 5VIBRATION ANALYSIS & FAULT DIAGNOSIS . 655.1DEFINE THE PROBLEM . 655.2DETERMINE THE MACHINE HISTORY . 655.3DETERMINE MACHINE DETAILS . 665.4VISUAL INSPECTION . 675.5USE THE SAME AMPLITUDE RANGE (SCALE) FOR ALL FFTS. 675.6INTERPRETING THE DATA . 705.6.1IDENTIFYING THE PROBLEM COMPONENT BASED ON FREQUENCY . 705.6.2IDENTIFYING THE PROBLEM COMPONENT BASED ON AMPLITUDE . 715.6.3REDUCING THE LIST OF POSSIBLE PROBLEMS BASED ON FREQUENCY . 715.7COMPARING TRI-AXIAL (HORIZONTAL, VERTICAL AND AXIAL) DATA745.7.1COMPARING HORIZONTAL AND VERTICAL READINGS . 745.7.2SIDE-BAND FREQUENCIES . 765.8VIBRATION DIAGNOSTICS . 785.8.1VIBRATION DUE TO UNBALANCE . 785.8.2BENT SHAFT PROBLEMS . 795.8.3IDENTIFYING A SHAFT WITH A KINK OR BEND CLOSE TO THE BEARING . 795.8.4IDENTIFYING A SIMPLE SHAFT BOW . 815.8.5VIBRATION DUE TO MISALIGNMENT . 815.8.6VIBRATION DUE TO LOOSENESS . 845.8.7LOOSENESS OF THE ROTATING SYSTEM . 845.8.8LOOSENESS OF THE SUPPORTING SYSTEM . 855.8.9MECHANICAL LOOSENESS AND SUB HARMONIC FREQUENCIES . 865.8.10VIBRATION DUE TO ECCENTRICITY . 875.8.11VIBRATION DUE TO RESONANCE . 88
5.9IDENTIFYING RESONANCE . 895.10VERIFYING RESONANCE PROBLEMS. 895.11VIBRATION DUE TO DEFECTIVE ROLLING-ELEMENT BEARINGS . 915.11.1Stage One-There's a Visible Flaw . 915.11.2Stage Two-It's Getting Worse . 915.11.3Stage Three - It’s Really Bad . 925.11.4Stage Four-The Last Hurrah . 945.12VIBRATION DUE TO AERODYNAMIC HYDRAULIC PROBLEMS . 945.13VIBRATION DUE TO INDUCTION MOTOR PROBLEMS . 965.13.1TEST FOR ELECTRICAL PROBLEMS UNDER LOAD . 975.13.2TEST FOR ELECTRICAL PROBLEMS AT NORMAL OPERATING TEMPERATURE. 975.13.3DISTINGUISHING BETWEEN MECHANICAL AND ELECTRICAL VIBRATION . 975.13.4VIBRATION DUE TO FIELD (STATOR) PROBLEMS . 985.13.5VIBRATION DUE TO ARMATURE PROBLEMS. 1005.14VIBRATION DUE TO GEAR PROBLEMS . 102CHAPTER 66.1ISO Standard for setting alarms: . 1046.1.16.2SETTING ALARM LIMIT . 104ISO 10816 RMS Alarm Limits . 104Spectrum Alarm Limits . 1076.2.1Band Alarms: . 1076.2.2Band Frequencies . 1086.2.3Mask/Envelope Alarms .
Vibration Analysis Level – 1 March 25-28, 2019 Organized by Centre for Vibration Analysis & Condition Monitoring (CVCM) Directorate of Nuclear Power Engineering Reactor (DNPER) PAKISTAN ATOMIC ENERGY COMMISSION
