US 12,117,419 B2
Method for detecting internal coating defects in pipe sample
Azhar Mehmood Memon, Dhahran (SA)
Assigned to KING FAHD UNIVERSITY OF PETROLEUM AND MINERALS, Dhahran (SA)
Filed by KING FAHD UNIVERSITY OF PETROLEUM AND MINERALS, Dhahran (SA)
Filed on Sep. 21, 2022, as Appl. No. 17/949,564.
Prior Publication US 2024/0094168 A1, Mar. 21, 2024
Int. Cl. G01N 29/24 (2006.01); G01N 29/11 (2006.01)
CPC G01N 29/2412 (2013.01) [G01N 29/11 (2013.01); G01N 2291/2636 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for detecting internal coating defects in a pipe sample, comprising:
recording a first plurality of Lamb mode scans of the pipe sample with an electromagnetic acoustic transducer (EMAT) sensor, wherein each Lamb mode scan of the first plurality of Lamb mode scans is measured along a length of the pipe sample in axial alignment with the pipe sample;
processing the first plurality of Lamb mode scans by singular spectrum analysis by applying a singular spectrum analysis (SSA) to the first plurality of Lamb mode scans to generate data from which the internal coating defects are identified in the pipe sample;
wherein the first plurality of Lamb mode scans are recorded at a frequency from dispersion curve of from 0.3 to 2 MHz, at a frequency of from 0.4 MHz to 2 MHz, a group velocity of from 1 mm/μs to 3 mm/μs, a phase velocity of from 5 mm/μs to 25 mm/μs, and a wave count of from 3 to 10.