11 NonDestructive Testing 1302 423 Industrial Materials Testing
![S =ct/2 S s = sound path [mm] c = sound velocity [km/s] t](https://slidetodoc.com/presentation_image/4b8207dcdb5ebda218c52636c05dfa72/image-20.jpg "S =ct/2 S s = sound path [mm] c = sound velocity [km/s] t")
- Slides: 46
บทท 11 การทดสอบโดยไมทำลาย Non-Destructive Testing 1302 423 Industrial Materials Testing Dr. Sukangkana Lee 1
l Introduction to NDT http: www. ndt-ed. org l Website บทเรยนศกษาดวยตวเอง http: //onlineshowcase. tafensw. edu. au/ndt/_common /indx_accessible. htm 5
Anode Cathode Tungsten filament Vacuum tube Tungsten target Tube to film distance ชน งาน X-rays Sample void Exposed film Film ฟลม 8 ray X-
ความลกของการทดสอบโดยใช Tube voltage (k. V) 150 250 400 1000 X-ray tubes ของเหลกกลา Penetration ability (mm) up to 25 up to 70 up to 100 5 -140 10
บทเรยน online l Viewing and Interpretation of Radiographs http: //onlineshowcase. tafensw. edu. au/ndt/co ntent/radiographic/task 8/accessible. htm 11
คลนตามยาว (Longitudinal wave) คลนตามขวาง (Transverse wave) 14
l คลนอล ตราโซนก จะผานไดในวสด แตจะผานไดนอยในอากาศ Medium Air (15 C) Water Oil Aluminium Copper Steel Polyethylene Longitude Velocity, (m/s) 330 1430 1740 6190 4600 5810 2340 Wavelengths (mm) for 1. 25 MHz 0. 26 1. 14 1. 39 4. 95 3. 68 4. 65 1. 8715
S =ct/2 S s = sound path [mm] c = sound velocity [km/s] t = time of flight (ms) 20
No Flaw Transmitter Work piece probe 1 3 2 Back wall echo 21
Flaw Detection Flaw Work piece probe 22
Elliptical defect Micro-porosity Angled defect 23
Angle probe 24
บทเรยน online l Fundamentals of Ultrasonic Imaging and Flaw Detection http: //zone. ni. com/devzone/cda/tut/p/id/33 68 25
• The penetrant used is often loaded with a fluorescent dye and the inspection is done under UV light to increase test sensitivity. 28
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What are the principles of penetrant examination in nondestructive examination? 31
Magnetic field lines N Magnetic particles S N S crack 33
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Magnetic particle indication Before After 36
Coil's magnetic field Eddy currents Conductive material 38
Eddy current solenoid coil Excitation coil Specimen Crack Eddy current Magnetic field Difference receive coil 40
Pancake-type coil Magnetic field Eddy current Specimen 41
Due date Final Examination Date: Time: 9 -12 AM l Laboratory Report Date: Time: no later than 4 PM l 46
