1. Date of download: 11/12/2016 Copyright © ASME. All rights reserved. From: High Frequency Guided Wave Natural Focusing Pipe Inspection With Frequency and Angle Tuning J. Pressure Vessel Technol. 2005;128(3):433-438. doi:10.1115/1.2218348 Axial distance at z=82in., L(m,1) mode group angular profiles and their envelope over frequency range 200–800kHz in a 4in. schedule 40 steel pipe with the circumferential excitation angle (a) 45deg and (b) 90deg. The transducer is located at θ=0deg and z=0 (in.). Figure Legend:

2. Date of download: 11/12/2016 Copyright © ASME. All rights reserved. From: High Frequency Guided Wave Natural Focusing Pipe Inspection With Frequency and Angle Tuning J. Pressure Vessel Technol. 2005;128(3):433-438. doi:10.1115/1.2218348 Schematic of ultrasonic transducer array locations and defect locations at the 4in. schedule 40 steel pipe Figure Legend:

3. Date of download: 11/12/2016 Copyright © ASME. All rights reserved. From: High Frequency Guided Wave Natural Focusing Pipe Inspection With Frequency and Angle Tuning J. Pressure Vessel Technol. 2005;128(3):433-438. doi:10.1115/1.2218348 Experiment equipments, which include the Matec® commercial ultrasonic A-scan control system and the high frequency phased array on a 4in. schedule 40 pipe for 200–800kHz frequency tuning inspection. Figure Legend:

4. Date of download: 11/12/2016 Copyright © ASME. All rights reserved. From: High Frequency Guided Wave Natural Focusing Pipe Inspection With Frequency and Angle Tuning J. Pressure Vessel Technol. 2005;128(3):433-438. doi:10.1115/1.2218348 Maximum amplitudes of axisymmetric and FAT natural focusing inspection results for the pipe #2. The defects include a 0.64% CSA RBH, a 0.76% CSA five-hole cluster at 94in. and a 1.01% CSA RBH at 110in. from the pipe end A. Figure Legend:

5. Date of download: 11/12/2016 Copyright © ASME. All rights reserved. From: High Frequency Guided Wave Natural Focusing Pipe Inspection With Frequency and Angle Tuning J. Pressure Vessel Technol. 2005;128(3):433-438. doi:10.1115/1.2218348 Schematic of ultrasonic transducer array locations and defect locations at the pipe #2, which is a 4in. schedule 40 steel pipe Figure Legend: