Spiral Wound Boiler Waterwalls

Scanned 60 feet²
(5.6 meters²) per minute

Collected nearly 15
million UT readings

Saved nearly $5 million
on repair costs

Challenge

• Manual inspection of spiral wound boiler with multi-lead rifle tubing left large gaps in inspection coverage
• Conventional UT cannot effectively differentiate the wall thickness between the ribs and gaps of internal rifling
• A potential tube leak could cause forced outages and wall replacement costs totaling upwards of $5 million

Solution

• Full-coverage Rapid Ultrasonic Gridding (RUG) inspection using TOKA® 4 robotic inspection platform
• Gecko Portal® software

Result

• No scaffolding or dedicated company resources were required for the inspection
• Nearly 15 million UT data readings obtained
• Saved the plant several millions of dollars in replacement costs by pinpointing areas in need of repair
• RUG’s specialized narrow beam immersion transducers reliably differentiated between rib and gap thickness in MLR tubing to provide accurate UT readings