Detection and assessment of high temperature hydrogen attack in steel pressure vessels using non-collinear wave mixing

Non-collinear wave mixing;High temperature hydrogen attack;Pulse inversion

Conway II, John Francis ; Reis ; Henrique M.

关键词: Non-collinear wave mixing;    High temperature hydrogen attack;    Pulse inversion;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/99271/CONWAYII-THESIS-2017.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

High temperature hydrogen attack (HTHA) is a problem that has been affecting energy related systems such as coal gasifiers and fuel processors for a long time. HTHA can result in sudden, catastrophic failures that are costly and dangerous. Prevention of this type of damage is of paramount importance, however no current detection technique is capable of non-destructively and reliably assessing the level of damage in HTHA affected vessels. This study presents a nondestructive testing approach that is capable of evaluating HTHA damage in pressure vessels made of carbon steels. A strategy of detection involving non-collinear wave mixing of ultrasonic waves and pulse-inversion is illustrated using a test sample extracted from a retired pressure vessel. Results show that nonlinear ultrasonics are capable of detecting and evaluating HTHA damage over the thickness of the specimen. These results are then compared to tensile tests conducted on tensile specimens machined from various depths through the thickness of the retired pressure vessel. The reduction in strength of the machined tensile specimens correlates well with nonlinear ultrasonic measurements, showing the reliability and validity of this method for inspection. The non-collinear wave mixing technique can be used with access only to the outside surface of a pressure vessel which makes this strategy appealing for in-situ inspection.