Ultrasonic Thickness Gauging - Level 2

Limited Certification for Ultrasonic Digital Thickness Measurement Topical Outline

1.0 Principles/Theory

• 1. 1 General
• 1.2 Principles of Acoustics
• 1.2.1 Nature of sound waves
• 1.2.2 Modes of sound wave generation
• 1.2.3 Velocity, frequency, and wavelength of sound waves
• 1.2.4 Attenuation/Scattering of sound waves

2.0 Equipment/Materials

• 2.1 Equipment
• 2.1.1 Pulse-echo instrumentation

a. Pulse generation
b. Signal detection
c. Display and recording methods, A-. B-, C-scan and digital
d. Sensitivity and resolution


• 2.1.2 Digital Thickness Instrumentation
• 2.1.3 Transducer operation and theory

a. Piezoelectric effect
b. Frequency (crystal-thickness relationships)
c. Types (straight, angle, single, dual, etc.)


• 2.2 Materials
• 2.2.1 Couplants

a. Purpose and principles
b. Material and their efficiency


• 2.2.2 Calibration blocks
• 2.2.3 Cables/connectors
• 2.2.4 Test specimen

3.0 Techniques/Calibrations — contact-straight-beam

4.0 Variables Affecting Test Results

• 4.1 Instrument performance variations
• 4.2 Transducer performance variations
• 4.3 Test specimen variations
• 4.3.1 Surface condition
• 4.3.2 Part geometry
• 4.3.3 Material structure

5.0 Procedure Specification Applications/ Thickness Measurement