Development of an Ultrasonic Inspection Technique
for Sizing of Cracks in Complex Geometry Plant
Publication: Publication Date: 1 May 2016Testing Method:
This paper discusses the development of an ultrasonic
time of flight diffraction-based inspection
technique for sizing surface-breaking vertical
cracks in complex geometry plant components like
a solid steam turbine rotor with integral discs. A
simple geometric model was developed.
Specimens containing vertical notches simulating
cracks in real-life rotors and holding devices for
affixing the transmitter and receiver probes in
plane and on opposite sides of the disc-like
portion of the specimens were designed and fabricated.
Experiments were conducted, and the
results show that the inspection technique
developed here can size such cracks with reasonable
accuracy. The technique can be useful for in-situ
condition assessment and remaining life
assessment of aged, in-service complex geometry
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