The Dual Linear Array™ probe for corrosion inspection provides many advantages over conventional ultrasonic dual element transducers. This phased array solution improves productivity through features such as larger beam coverage, faster scan speed, and C-scan imaging with increased data-point density. The pitch-catch technique used by this new probe offers better near-surface resolution and pit detection in corrosion survey applications than standard phased array pulse-echo, improving the probability of detection of critical wall thinning. 

Thanks to new features, such as built-in irrigation and a replaceable delay line that can be contoured to better adapt to pipe curvature, the DLA corrosion probe can now be used to perform automated inspection.

Probe Benefits and Features

• Detect defects as shallow as 1 mm (0.04 in.) below the surface.
• Cost-effective replaceable delay line.
• Built-in irrigation.
• High temperature option to scan hot surfaces.
• Beam coverage width of up to 30 mm (1.18 in.).
• Versatile quick adjustment system adapts to diameters from 4 in. to flat.
• Durable carbide wear plates protect the wedge.
• Typical inspection depth of 1 to 80 mm in carbon steel.
• OmniScan® configuration files (MX, MX2, and SX) on a USB key.

OmniScan Software Features

• Side, end, and top view imaging (B-scan, D -scan, C-scan).
• Full high-resolution A-scan storage.
• Two configurable detection gates.
• Offline analysis on an OmniScan flaw detector or a computer using OmniPC™ software.

New Features, New Possibilities

The combination of the DLA corrosion probe and the OmniScan SX flaw detector is an affordable inspection option. This solution is easy to set up and simple to use: load the supplied setup file, check the calibration, then inspect and record the data. No pulse/receive (PR) instrument is required.

Whether you want to manually screen an area using an encoder or conduct high-speed, full volume mapping with the MapROVER™ motorized scanner, the DLA corrosion enables you to quickly and easily perform C-scans on smooth surfaces. The innovative probe stabilization system combined with a contoured removable delay line and irrigation features provides excellent sound transmission on piping surfaces as small as 4 inches in diameter. The DLA corrosion probe is also available in a high temperature version capable of inspecting surfaces up to 150°C (300°F).

DLA corrosion probe used with the MapROVER scanner for automated inspections.

Dual Array Pitch-Catch Technique

Like dual element UT probes, dual linear array probes incorporate separate transmitting and receiving elements mounted on delay lines that are cut at an angle. This configuration generates beams that focus beneath the surface of the test piece, which considerably decreases the amplitude of surface reflection. This results in increased near-surface resolution, providing higher probability of detection of critical defects such as pitting, creep damage, and HIC (hydrogen induced cracking).

Pitch-Catch	Pulse-Echo

Compared to phased array pulse-echo, the pitch-catch technique produces very little interface echo, offering better near-surface resolution.

B-scan image of corrosion on carbon-steel pipe.