Further field trials and changes have been made to improve the reliability of the robotic system and reduce the time required for insertion into and inspection of coke drums. Scans are performed at a speed of approximately one inch per second, allowing significant sections of a drum to be examined during a 4-hour window.
CIAI has successfully used the ACFM crawler inside a coke drum. The ACFM probe and crawler were driven around the circ weld and across other obvious indications. CIAI was able to collect data and correlate ACFM findings with the site’s results obtained by grinding out all LDP indications. During this field trial small, medium and large cracks were encountered and accurately sized. As well, stress cracking in the cladding, often referred to as “elephant skin” was scanned. Each type of flaw had distinct characteristics that were readily discernable to the ACFM operator and no significant flaws were missed.
This impressive performance demonstrates that remote ACFM crack detection works in the coke drum environment and is a useful tool that minimizes downtime while providing accurate results.
