29-08-2011, 02:38 PM
ULTRASONIC_TECHNIQUES_FOR_H.PPT (Size: 690.5 KB / Downloads: 199)
INTRODUCTION
CAUSE OF CORROSION – MOISTURE, WATER, CRACKS
AREAS AFFECTED – SURFACE, LAP JOINTS, FASTENERS
3. NEED OF NDT
NON DESTRUCTIVE TESTS (NDT)
VISUAL INSPECTION
MAGNETIC PARTICLE TEST
LIQUID (DYE) PENITRATION TEST
X – RAY PENETRATION INSPECTION
EDDY CURRENT INSPECTION
ULTRASONIC INSPECTION
DEFECTS OF CONVENTIONAL SYSTEMS
INSPECTION FROM TOP NORMAL TO SURFACE
2. TIME CONSUMING FOR POINT TO POINT INSPECTION
3. INABILITY TO DETECT (a) DISBONDS IN MULTILAYER
(b) FATIGUE CRACKS AT FASTNERS
PRINCIPLE OF OPERATION
GUIDEDED WAVES DISPRERSIVE WAVE VELOCITY IS A Fn OF FREQUENCY- THICKNESS PRODUCT
MATERIAL CHANGE b/w 2 LAYERS AFFECTS
1. PROPAGATING MODE AMPLITUDE
2. VELOCITY
3. FREQUENCY SPECTRUM
4. TIME OF FLIGHT