AUT Corrosion Mapping systems utilizing mechanical scanners are employed regularly for equipment condition inspections. Often referred to as AUT Corrosion Mapping, C-Scan or Ultrasonic Corrosion Mapping, this NDT method quickly identifies wall loss and presents a detailed report relative to location, thickness values and area.
Automated Ultrasonic Testing (AUT) Corrosion Mapping plots the opposite surface of pressure vessels, piping, tanks, heat exchangers, and more. This is critical to determine not only the remaining thickness but the topography and area affected. Access to only one side is needed so the underside of a tank floor can be examined from inside the tank, the ID surface of a piping system can be mapped from the outside surface, etc. The systems are capable of acquiring actual wall thickness over large areas of test subjects while the system is on or off-line. AUT Corrosion Mapping is also used for remaining life determinations as prescribed by the facility’s Mechanical Integrity program.
Applications for AUT Corrosion Mapping:
Opposite side corrosion, pitting, and erosion
Mid-wall or sub-surface indications like laminations, inclusions, and blisters
Locate and detect Hydrogen induced cracking (HIC) and blisters
Advantages of AUT Corrosion Mapping include:
High degree of repeatability
Location and dimension data for every discontinuity can be compared for repeat scans in the same location. These comparison reports highlight specified area flaw growth or corrosion rates as well as individual discontinuities.
Creates a top down (C-scan) visual illustration of damage as well as a side view (cross sectional) visual illustration of damage
Encoded scanning allows for a large amount of data to be captured in a very short time.
Limitations of AUT Corrosion Mapping include:
Accessibility of area that needs inspected
Surface cleanliness and roughness of part that needs inspected
Tracks or magnetic strips may be needed for stainless or other nonmagnetic surfaces