UT vs RT: Choosing the Right Weld Inspection Method
When ultrasonic testing beats radiography — safety, speed, cost and code acceptance compared.
Choosing between ultrasonic and radiographic weld inspection comes down to the flaw types you care about, access, safety and how the result must be recorded.
Radiography (RT) excels at volumetric flaws like porosity and slag and produces a universally accepted image, but needs two-sided access, a radiation exclusion zone and handling of sources or film.
Ultrasonic methods — especially encoded PAUT and TOFD — detect planar flaws and cracks more reliably, size them through-wall, need single-sided access and produce a digital record with no radiation. Increasingly, ASME Code Case 2235 and project specs accept PAUT in lieu of RT. The right answer is application-specific; TESKO advises and delivers both.