Phased Array/TOFD
Phased Array Ultrasonic Testing (PAUT) is an advanced nondestructive examination technique that utilizes a multi- element ultrasonic testing probes. A Phased Array probe typically consists of 16 to 128 individual elements, each of which is pulsed individually with computer-calculated timing. Thus electronically controlled wave steering, focusing, and scanning can be achieved.
These technologies has ability to collect and encode full volumetric data, PAUT and ToFD brings code compliance and auditable results to the everyday ultrasonic examination. This makes Phased Array and ToFD an effective and efficient alternative to Radiographic inspection. Since there is no radiation or environmental hazards, Phased Array and TOFD inspections can access radiation sensitive areas, increase project production by not displacing other working teams in the area, and maximizes on-site and personnel safety.
Time-Of-Flight Diffraction (TOFD)
Time-Of-Flight Diffraction (TOFD) is a technique based on time of flight of waves and the diffraction produced by the extremities of the discontinuity. TOFD consists of a pair of transducers facing each other on angled wedges defined to produce longitudinal waves. One pulses while the other receives and are separated by a known distance that ensures coverage of the desired zone.
TOFD is recognized for its high level of accuracy and precision regarding sizing. It is complemented by PAUT or Conventional UT in order to cover the top and bottom dead zones.
Advantages of PAUT and TOFD
• Excellent repeatability, high level of sensitivity & better flaw characterization and sizing.
• Increased coverage of the area of interest than with a single probe and wedge.
• Increased Probability of Detection (POD) during weld inspection.
• Increased speed of inspection.
• Data recording for future analysis/record-keeping.
• Ability to inspect complex geometries
• Detection of both embedded flaws and surface connected ones.