Title Page
ABSTRACT
Contents
NOMENCLATURES 26
PREFACE 28
CHAPTER 1. ACOUSTIC EMISSION TECHNIQUE 31
1.1. Introduction 31
1.2. Formation and propagation of elastic waves 33
1.3. Development of applications using Acoustic Emission technique 36
1.4. Application fields 38
CHAPTER 2. DIAGNOSTIC CONDITION THEORY 43
2.1. Fast Fourier Transform (FFT) 43
2.1.1. Fourier Transform 43
2.1.2. Discrete Fourier Transform 43
2.1.3. The Fast Fourier Transform 46
2.2. Octave band 47
2.3. Kurtosis 50
2.4. Time Synchronous Averaging (TSA) 55
2.4.1. Time synchronous averaging 55
2.4.2. Cubic spline interpolation 58
2.4.3. Carry out cubic spline interpolation algorithm 61
2.4.4. Time synchronous averaging flowchart 63
2.5. Root Mean Square (RMS) 65
2.6. Peak to Peak (P2P) 69
CHAPTER 3. ENGINE VIBRATION ANALYSIS AND MONITORING SYSTEM WITH ACOUSTIC EMISSION SENSOR (EVAMOS AE) SOFTWARE USING C# 72
3.1. Introduction 72
3.2. Overview of software 74
3.2.1. Main window 74
3.2.2. Configuration window 80
3.2.3. Display window 85
3.3. Functions and flowcharts 87
3.3.1. Check plugged devices and collect information 88
3.3.2. Connect NI hardware and receive data 89
3.3.3. Record data 91
3.3.4. Calculate shaft speed 97
3.4. Additional flowcharts 106
3.4.1. Create tree view for name of devices and channels 106
3.4.2. Create display window 110
3.4.3. Manual and automatic recording mode 111
3.5. Using software 112
CHAPTER 4. ADDITIONAL FUNCTIONS FOR SIGNAL PROCESSING 115
4.1. Convert DAT file to TEXT file 115
4.1.1. Convert file function 115
4.1.2. Cut file based on Tachometer signal function 118
4.1.3. Using software 135
4.2. Calculate Fast Fourier Transform function 142
4.2.1. Flowchart of calculate FFT function 142
4.2.2. Using software 147
4.2.3. Results 150
CHAPTER 5. CASE STUDIES 152
5.1. TOP bracing function 153
5.1.1. Overview of top bracing 153
5.1.2. Mechanical top bracing 154
5.1.3. Hydraulic top bracing 157
5.2. Experimental equipment 162
5.2.1. Overview of acoustic emission measuring system 162
5.2.2. Kistler Acoustic Emission Sensor 164
5.2.3. Vallen Acoustic Emission sensor 169
5.2.4. Medium transmitter NI USB - 6366 BNC 171
5.3. Case study 1: High frequency vibration on MAN B&W 6G70ME-C9.5 equipped on 157.000 TON Carrier Oil Tanker (COT) vessel 174
5.3.1. The high frequency vibration at cylinder's body of cylinder No.6 in normal firing and misfiring operation modes 176
5.3.2. The high frequency vibration at cylinder's body of cylinder No.5 when cylinder No.6 in misfiring and normal firing condition 178
5.3.3. The high frequency vibration at cylinder's body of cylinder No.6 with TOP bracing function 180
5.3.4. The comparison between two types of magnetic base 184
5.3.5. Comparison between RAW and RMS signal of Kistler sensor 188
5.4. Case study 2: High frequency vibration on MAN B&W 6G60ME-C9.5 equipped on 80.000 TON Liquid Petro Gas (LPG) vessel 192
5.4.1. The high frequency vibration measured by Kistler sensor of cylinder No.4 in normal firing mode 194
5.4.2. The high frequency vibration measured by Vallen sensor of cylinder No.4 in normal firing mode 197
5.4.3. The high frequency vibration measured by Vallen sensor of cylinder No.4 in misfiring condition 199
5.5. Case study 3: High frequency vibration on MAN B&W 7G80ME-C9.5 equipped on 300.000 TON Very Large Crude Carrier (VLCC) 202
5.5.1. The high frequency vibration measured by Kistler sensor at cylinder No.7 body position 204
5.5.2. The high frequency vibration measured by Kistler sensor at Injector position of cylinder No.7 206
5.5.3. The high frequency vibration measured by Vallen sensor at cylinder No.7 body position 208
5.5.4. The high frequency vibration measured by Vallen sensor at Injector position of cylinder No.7 210
5.6. Case study 4: High frequency vibration on MAN B&W 11G90ME - C10.5 equipped on 15100 CNTR (container) vessel 213
5.6.1. The high frequency vibration measured by Kistler sensor at cylinder No.4 body position 215
5.6.2. The high frequency vibration measured by Kistler sensor at cylinder No.4 injector position 217
5.6.3. The high frequency vibration measured by Vallen sensor at cylinder No.4 body position 219
5.6.4. The high frequency vibration measured by Vallen sensor at cylinder No.4 injector position 221
5.7. Case study 5: High frequency vibration on MAN B&W 7G80ME- C9.5 equipped on 325.000 TON (bulk carrier) vessel 224
5.7.1. The high frequency vibration measured by Kistler sensor at cylinder No.6 body position 226
5.7.2. The high frequency vibration measured by Kistler sensor at Injector position of cylinder No.6 228
5.7.3. The high frequency vibration measured by Vallen sensor at cylinder No.6 body position 230
5.7.4. The high frequency vibration measured by Vallen sensor at cylinder No.4 injector position 232
5.8. Case study 6: Application of TSA and Kurtosis method in analyzing high frequency vibration 234
5.8.1. TSA method in analyzing high frequency vibration 234
5.8.2. Kurtosis method in analyzing high frequency vibration 237
CHAPTER 6. CONCLUSION 242
Reference 245
Table 2.1. The comparison between FFT and DFT 46
Table 2.2. Octave band 48
Table 2.3. One-third octave band 49
Table 2.4. Resampling result 58
Table 3.1. Common function to write file and type of data 91
Table 3.2. Testing computer specification 93
Table 3.3. Time of writing file 93
Table 5.1. Mechanical top bracing arrangement parameters 157
Table 5.2. Recommendation value for arrangement hydraulic top bracing 160
Table 5.3. Kistler AE sensor specifications 166
Table 5.4. Vallen sensor specifications 170
Table 5.5. Characteristics of AI channels of NI USB - 6366 BNC 172
Table 5.6. The specification of engine and propulsion shafting system 175
Table 5.7. The specification of engine and propulsion shafting system 193
Table 5.8. The specification of engine and propulsion shafting system 203
Table 5.9. The specification of engine and propulsion shafting system 214
Table 5.10. The specification of engine and propulsion shafting system 225
Fig. 1.1. Elastic waves (acoustic emission) is emitted by the sudden change... 31
Fig. 1.2. Proposed structure of AE measuring system 36
Fig. 1.3. Comparison of NDT principles using active or passive techniques 37
Fig. 2.1. Roots distribution 45
Fig. 2.2. The probability density of some special curves 54
Fig. 2.3. Excess kurtosis coefficient of some special curves 54
Fig. 2.4. Time synchronous averaging technique 56
Fig. 2.5. Interpolation simulation 62
Fig. 2.6. Flowchart of time synchronous averaging method 63
Fig. 2.7. Interpolation algorithm with 5 points 64
Fig. 2.8. Interpolation result 65
Fig. 2.9. Sin(x) function with peak and RMS value 66
Fig. 2.10. Average value of sin(x) function 68
Fig. 2.11. Peak and P2P value 69
Fig. 2.12. The relationship among Peak, P2P, RMS and Average value of... 70
Fig. 3.1. EVAMOS AE - Main window 75
Fig. 3.2. Main flowchart of monitoring window 77
Fig. 3.3. Alarm message and disable connect hardware function 78
Fig. 3.4. Save setting feature 80
Fig. 3.5. Configuration window - Analyzer setup tab 81
Fig. 3.6. Configuration window - Input setup tab 81
Fig. 3.7. Configuration window - Recording setup tab 82
Fig. 3.8. Configuration window - EDiMS setup tab 82
Fig. 3.9. Main flowchart of configuration window 83
Fig. 3.10. Display window 86
Fig. 3.11. Display window arrangement 87
Fig. 3.12. Check plugged devices and collect information 88
Fig. 3.13. Connect NI hardware and receive data 90
Fig. 3.14. Real-writing time of EVAMOS AE with 2 MS/s and 8 channels 94
Fig. 3.15. Write DAT file flowchart 95
Fig. 3.16. Flowchart of write file function 96
Fig. 3.17. Pulse counting method 97
Fig. 3.18. Period measuring method 99
Fig. 3.19. Working principle of gap/magnetic switch sensor 100
Fig. 3.20. Installation of gap/magnetic switch sensor 100
Fig. 3.21. Rotary encoder inside electric motor 101
Fig. 3.22. Installation of roller encoder 101
Fig. 3.23. Rotec laser tachometer 102
Fig. 3.24. Convert signal from sinusoidal to square 103
Fig. 3.25. Real signal and trigger level 103
Fig. 3.26. Calculating shaft speed flowchart 104
Fig. 3.27. Convert positive pulse process 105
Fig. 3.28. Convert negative pulse process 105
Fig. 3.29. Tree view for name of devices and channels 106
Fig. 3.30. Flowchart of creating tree view 107
Fig. 3.31. Double click on name of NI device 108
Fig. 3.32. Double click on name of channel 109
Fig. 3.33. Create display window flowchart 110
Fig. 3.34. Flowchart of manual and automatic recording mode 112
Fig. 3.35. NI device is successfully connected with computer 113
Fig. 4.1. Convert DAT file to TEXT file - Main window 115
Fig. 4.2. Convert DAT file to TEXT file - Setting window 116
Fig. 4.3. Main flowchart of convert file function 117
Fig. 4.4. Tachometer signal of low speed 118
Fig. 4.5. Flowchart of cut 1 revolution with low speed 119
Fig. 4.6. Tachometer signal of high speed 120
Fig. 4.7. Flowchart of cut 1 revolution with high speed 121
Fig. 4.8. Cut multi revolutions with low speed 122
Fig. 4.9. Flowchart of cut multi revolution with low speed of shaft 123
Fig. 4.10. Cut multi revolutions with high speed 124
Fig. 4.11. Flowchart of cut multi revolution with high speed of shaft 125
Fig. 4.12. Cut multi file 126
Fig. 4.13. Simple flowchart of cut multi file 127
Fig. 4.14. Overall flowchart 128
Fig. 4.15. Flowchart of changing file name 129
Fig. 4.16a. Cut file based on conditions 130
Fig. 4.16b. Cut file based on conditions 131
Fig. 4.17. Cut inside segments between some pulses 132
Fig. 4.18. Flowchart of determine pulses position and count pulse 133
Fig. 4.19. Determine pulse and count remaining pulse 134
Fig. 4.20. Convert DAT file to TEXT file - Convert folder window 135
Fig. 4.21. Setting file 136
Fig. 4.22. Content of Setting file 137
Fig. 4.23. Setting window 138
Fig. 4.24. Running software 139
Fig. 4.25. Set parameters 139
Fig. 4.26. Converted file 140
Fig. 4.27. Tachometer signal with 3 revolutions 140
Fig. 4.28. Converted files with 3 revolutions and 2 files 141
Fig. 4.29. Overview of calculate FFT function 142
Fig. 4.30. Use all number samples mode 143
Fig. 4.31a. Octave algorithm 144
Fig. 4.31b. Octave algorithm 145
Fig. 4.32. Use fixed number sample mode 146
Fig. 4.33. FFT calculation tool 147
Fig. 4.34. Using fixed number sample mode - Setting 150
Fig. 4.35. Using fixed number sample mode - FFT file 150
Fig. 4.36. Using all number samples mode - Setting 151
Fig. 4.37. Using all number samples mode - FFT file 151
Fig. 5.1. Mechanical top bracing 155
Fig. 5.2. Mechanical top bracing arrangement 156
Fig. 5.3. Outline of a hydraulic top bracing 158
Fig. 5.4. Two types of hydraulic top bracing 159
Fig. 5.5. Hydraulic top bracing arrangement 160
Fig. 5.6. Hydraulic top bracing arrangement - viewed from top 161
Fig. 5.7. Diagram of measuring system 162
Fig. 5.8. Kistler Acoustic Emission sensor 165
Fig. 5.9. Type of PFA jacketed cable with armor conduit 165
Fig. 5.10. Type of PFA jacketed cable without armor conduit 166
Fig. 5.11. Diagram of transmitter box 167
Fig. 5.12. Range of frequency 168
Fig. 5.13. Vallen AE sensor VS 30-V 169
Fig. 5.14. MKPA - 5150U preamplifier 170
Fig. 5.15. NI USB - 6366 BNC front panel and pinout 171
Fig. 5.16. Measuring position of sensors 174
Fig. 5.17. Vibration in transverse direction result (waterfall) of cylinder No.6... 176
Fig. 5.18. Vibration in transverse direction result (contour map) of cylinder... 176
Fig. 5.19. Vibration in transverse direction result (waterfall) of cylinder No.6... 177
Fig. 5.20. Vibration in transverse direction result (contour map) of cylinder... 177
Fig. 5.21. Vibration in transverse direction result (waterfall) of cylinder No.5... 178
Fig. 5.22. Vibration in transverse direction result (contour map) of cylinder... 178
Fig. 5.23. Vibration in transverse direction result (waterfall) of cylinder No.5... 179
Fig. 5.24. Vibration in transverse direction result (contour map) of cylinder... 179
Fig. 5.25. Vibration in transverse direction result (waterfall) of cylinder No.6... 180
Fig. 5.26. Vibration in transverse direction result (contour map) of cylinder... 180
Fig. 5.27. Vibration in transverse direction result (waterfall) of cylinder No.6... 181
Fig. 5.28. Vibration in transverse direction result (contour map) of cylinder... 181
Fig. 5.29. Vibration in transverse direction result (waterfall) of cylinder No.6... 182
Fig. 5.30. Vibration in transverse direction result (plot) of cylinder No.6... 182
Fig. 5.31. Vibration in transverse direction result (waterfall) of cylinder No.6... 183
Fig. 5.32. Vibration in transverse direction result (plot) of cylinder No.6... 183
Fig. 5.33. Two types of magnetic are tested 184
Fig. 5.34. The results of experiment in time domain 185
Fig. 5.35. The results of experiment in time domain 185
Fig. 5.36. Vibration in transverse direction result (waterfall) of cylinder No.5... 186
Fig. 5.37. Vibration in transverse direction result (contour map) of cylinder... 186
Fig. 5.38. Vibration in transverse direction result (waterfall) of cylinder No.5... 187
Fig. 5.39. Vibration in transverse direction result (contour map) of cylinder... 187
Fig. 5.40. Time domain of RMS and RAW signal of Kistler sensor 188
Fig. 5.41. Vibration in transverse direction result (waterfall) of cylinder No.6... 189
Fig. 5.42. Vibration in transverse direction result (contour map) of cylinder... 189
Fig. 5.43. Vibration in transverse direction result (waterfall) of cylinder No.6... 190
Fig. 5.44. Vibration in transverse direction result (contour map) of cylinder... 190
Fig. 5.45. Measuring position of sensors - protected cover of cylinder body 192
Fig. 5.46. Measuring position of sensors - directly mount on cylinder body 192
Fig. 5.47. Time domain of vibration of Kistler sensor - directly mounted on... 194
Fig. 5.48. Time domain of vibration of Kistler sensor - mount on protected... 194
Fig. 5.49. Vibration in transverse direction result (waterfall) of cylinder No.4... 195
Fig. 5.50. Vibration in transverse direction result (contour map) of cylinder... 195
Fig. 5.51. Vibration in transverse direction result (waterfall) of cylinder No.4... 196
Fig. 5.52. Vibration in transverse direction result (contour map) of cylinder... 196
Fig. 5.53. Vibration in transverse direction result (waterfall) of cylinder No.4... 197
Fig. 5.54. Vibration in transverse direction result (contour map) of cylinder... 197
Fig. 5.55. Vibration in transverse direction result (waterfall) of cylinder No.4... 198
Fig. 5.56. Vibration in transverse direction result (contour map) of cylinder... 198
Fig. 5.57. Vibration in transverse direction result (waterfall) of cylinder No.4... 199
Fig. 5.58. Vibration in transverse direction result (contour map) of cylinder... 199
Fig. 5.59. Vibration in transverse direction result (waterfall) of cylinder No.4... 200
Fig. 5.60. Vibration in transverse direction result (contour map) of cylinder... 200
Fig. 5.61. Vallen sensor (left) and Kistler sensor (right) mounted at... 202
Fig. 5.62. Vallen sensor (right) and Kistler sensor (left) mounted at Injector 202
Fig. 5.63. Vibration in axial direction result (waterfall) of cylinder No.7... 204
Fig. 5.64. Vibration in axial direction result (contour map) of cylinder No.7... 204
Fig. 5.65. Vibration in axial direction result (waterfall) of cylinder No.7... 205
Fig. 5.66. Vibration in axial direction result (contour map) of cylinder No.7... 205
Fig. 5.67. Vibration result (waterfall) at Injector position of cylinder No.7 in... 206
Fig. 5.68. Vibration result (contour map) at Injector position of cylinder... 206
Fig. 5.69. Vibration result (waterfall) at Injector position of cylinder No.7 in... 207
Fig. 5.70. Vibration result (contour map) at Injector position of cylinder... 207
Fig. 5.71. Vibration in axial direction result (waterfall) of cylinder No.7... 208
Fig. 5.72. Vibration in axial direction result (contour map) of cylinder No.7... 208
Fig. 5.73. Vibration in axial direction result (waterfall) of cylinder No.7... 209
Fig. 5.74. Vibration in axial direction result (contour map) of cylinder No.7... 209
Fig. 5.75. Vibration result (waterfall) at Injector position of cylinder No.7 in... 210
Fig. 5.76. Vibration result (contour map) at Injector position of cylinder... 210
Fig. 5.77. Vibration result (waterfall) at Injector position of cylinder No.7 in... 211
Fig. 5.78. Vibration result (contour map) at Injector position of cylinder... 211
Fig. 5.79. Vallen sensor (left) and Kistler sensor (right) mounted at cylinder... 213
Fig. 5.80. Vallen sensor (upper) and Kistler sensor (lower) mounted at... 213
Fig. 5.81. Vibration result (waterfall) of cylinder No.4 body in Misfiring... 215
Fig. 5.82. Vibration result (contour map) of cylinder No.4 body in Misfiring... 215
Fig. 5.83. Vibration result (waterfall) of cylinder No.4 body in Normal firing... 216
Fig. 5.84. Vibration result (contour map) of cylinder No.4 body in Normal... 216
Fig. 5.85. Vibration result (waterfall) at Injector position of cylinder No.4 in... 217
Fig. 5.86. Vibration result (contour map) at Injector position of cylinder... 217
Fig. 5.87. Vibration result (waterfall) at Injector position of cylinder No.4 in... 218
Fig. 5.88. Vibration result (contour map) at Injector position of cylinder... 218
Fig. 5.89. Vibration result (waterfall) of cylinder No.4 body in Misfiring... 219
Fig. 5.90. Vibration result (contour map) of cylinder No.4 body in Misfiring... 219
Fig. 5.91. Vibration result (waterfall) of cylinder No.4 body in Normal firing... 220
Fig. 5.92. Vibration result (contour map) of cylinder No.4 body in Normal... 220
Fig. 5.93. Vibration result (waterfall) at Injector position of cylinder No.4 in... 221
Fig. 5.94. Vibration result (contour map) at Injector position of cylinder... 221
Fig. 5.95. Vibration result (waterfall) at Injector position of cylinder No.4 in... 222
Fig. 5.96. Vibration result (contour map) at Injector position of cylinder... 222
Fig. 5.97. Vallen sensor (left) and Kistler sensor (right) mounted at injector... 224
Fig. 5.98. Vallen sensor (left) and Kistler sensor (right) mounted at cylinder... 224
Fig. 5.99. Vibration in transverse direction result (waterfall) of cylinder No.6... 226
Fig. 5.100. Vibration in transverse direction result (contour map) of cylinder... 226
Fig. 5.101. Vibration in transverse direction result (waterfall) of cylinder... 227
Fig. 5.102. Vibration in transverse direction result (contour map) of cylinder... 227
Fig. 5.103. Vibration result (waterfall) at Injector base position of cylinder... 228
Fig. 5.104. Vibration result (contour map) at Injector base position of... 228
Fig. 5.105. Vibration result (waterfall) at Injector base position of cylinder... 229
Fig. 5.106. Vibration result (contour map) at Injector base position of... 229
Fig. 5.107. Vibration in transverse direction result (waterfall) of cylinder... 230
Fig. 5.108. Vibration in transverse direction result (contour map) of cylinder... 230
Fig. 5.109. Vibration in transverse direction result (waterfall) of cylinder... 231
Fig. 5.110. Vibration in transverse direction result (contour map) of cylinder... 231
Fig. 5.111. Vibration result (waterfall) at Injector base position of cylinder... 232
Fig. 5.112. Vibration result (contour map) at Injector base position of... 232
Fig. 5.113. Vibration result (waterfall) at Injector base position of cylinder... 233
Fig. 5.114. Vibration result (contour map) at Injector base position of... 233
Fig. 5.115. Time domain: Original signal (blue), apply TSA method with 3... 234
Fig. 5.116. Time domain: Original signal (blue), apply TSA method with 13... 234
Fig. 5.117. Vibration in transverse direction result (waterfall) of cylinder... 235
Fig. 5.118. Vibration in transverse direction result (contour) of cylinder No.5... 235
Fig. 5.119. Vibration in transverse direction result (waterfall) of cylinder... 236
Fig. 5.120. Vibration in transverse direction result (contour) of cylinder No.5... 236
Fig. 5.121. Vibration in axial direction result (waterfall) of cylinder No.7... 237
Fig. 5.122. Vibration in axial direction result (contour) of cylinder No.7... 237
Fig. 5.123. Vibration in axial direction result (waterfall) of cylinder No.7... 238
Fig. 5.124. Vibration in axial direction result (waterfall) of cylinder No.7... 238
Fig. 5.125. Vibration in axial direction result (time domain) of cylinder No.7... 239
Fig. 5.126. Vibration in axial direction result (time domain) of cylinder No.7... 239
Fig. 5.127. Vibration in axial direction result (waterfall) of cylinder No.7... 240
Fig. 5.128. Vibration in axial direction result (waterfall) of cylinder No.7... 240
Fig. 5.129. Vibration in axial direction result (waterfall) of cylinder No.7... 241
Fig. 5.130. Vibration in axial direction result (waterfall) of cylinder No.7... 241