Conventional Cscan applications place a staight beam transducer on the smooth OD surface of a component. A Cscan gate is then placed on the ID surface signal to plot ID corrosion. However there is a class of applcations, most notably pipeline pigging, in which a straight beam transducer must be scanned on the ID surface (which is normally the corroded surface) in order to plot the corrosion of the ID surface. This technique is often referred to as inside out corrosion map, scanning from the inside surface looking to the outside surface, and generating a corrosion map of both the inside and outside surfaces.

Raster scanning on a corroded surface requires a bubbler with a wide foot print. The wide footprint allows the transducer to contour to the curved surface and slide smoothly and evenly across the rough corroded surface while maintaining couplant using a contact immersion (bubbler) technique. The bubbler technique also allows for reliable coupling while the transducer is being rastered at extremely high scan speeds.

The AIS RoboScanner performs the inside out corrosion map using a patented airless bubbler. The airless bubbler maintains a smooth laminar water column providing for high sensitivity examination devoid of water column noise and attenuation. When combined with the NB-2000 Plus, the RoboScanner can plot both front surface (ID corrosion) and back surface (OD corrosion) simultaneously.

Inside OUt Corrosion Mapping Summary:

• Scan with the transducer on the corroded side of the component
• Requires an airless bubbler for high sensitivity and high speed scanning
• Can generate large area Cscans of both the ID and OD surfaces simultaneoulsy
• Full wave form capture at high resolution and high scan speeds
• Automated contrast enhancement of both front and back surface Cscans
• Easy to use software combines large area Cscans to create even larger area Cscans.

 

Inside Out Corrosion Mapping