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Advanced Inspection
Applications- NII as replacement of IVI
- Pressure Vessels
- Pipelines
- Pipework
- Structures
- Subsea
- Heat Exchangers and Tubing
- Turbines
- Data Science
- Equipment integrity and reliability
- Robotic Tank Inspection
- Internal Inspection of Caissons
Time of Flight Diffraction (TOFD)
ToFD screening has been developed jointly between Sonomatic and Shell Global Solutions with the objective of providing a method of rapid, yet accurate corrosion mapping.
The ToFD footprint at the internal surface is approx 2x the material thickness. Linear scanning speeds are very high, and a special range of scanners have been developed by Sonomatic’ mechanical design engineers, and software by our software engineers to facilitate rapid scanning. The lateral resolution is poor, but the thru-wall resolution is remarkably high.
ToFD is an ultrasonic technique originally developed for crack detection. Unlike conventional Pulse Echo, the transmitter receiver in arrangement in ToFD floods the region between the probes with ultrasound. Crack tips are identified by diffraction but it is also very effective for the detection and sizing of Weld Root Erosion or Corrosion (WRE or WRC).
The nature of the reflection of the ultrasound from eroded/corroded areas in the TFD pitch-catch arrangement makes it ideal for the detection of Weld Root Erosion/Corrosion. This approach has a proven track record as an accurate method for the detection and monitoring of corrosion and erosion damage in the weld and heat affected zones.
