Efficient use of scheduled plant outage time and the coordination of many third-party contractors create a need for speed and flexibility. Gecko was entrusted, by a coal-fired utility power plant in Wyoming, to perform robotic ultrasonic testing inspection on back-end equipment. In delivering Gecko’s industry changing robotic inspection service, we collected over 4.32 million UT thickness measurements on a Circulating Dry Scrubber (CDS) system and a Flue Gas Stack Liner at the plant.
The customer’s prior method for inspection of their CDS system involved building a platform over the wire mesh on the venturis with inspectors reaching for manual inspection measurements at the base of the scrubber. The problem with this methodology is the remaining 81 feet (24m) that could not be inspected without the risk, time, and cost (upwards of $80,000) of scaffolding.
Two NDE Level II inspectors and one robot completed the inspection in 24 hours; despite the proposed estimate of three full days. As the COVID-19 pandemic was about to reach the apex during the month of the inspection, the importance of minimizing people on-site was paramount.
Within 48 hours of the completed inspection, the results were delivered to the customer through Gecko’s own proprietary portal. Gecko Portal presented 4.32 million data points into actionable data in the material thickness. Across both assets, 36 readings per square foot (388 per square meter) were captured to validate the accuracy of the measurements presented in grids. To increase usability, the TOKA 3 robot captures a high definition (HD) photograph on every linear foot of inspection. Coupling exact location dimensions with visual references stitched into the color-coded grid gave plant maintenance personnel all of the tools to address relatively severe issues along the CDS cone and cylinder.
The speed with which this information was delivered to the client enabled data-driven guidance on remediation needs during the same outage the inspection was performed. The importance of this data for the stack flue liner is illustrated by a Power Magazine article, which points out that protecting areas from corrosion may cost as little as $10,000 while the cost of repairing or replacing a stack could reach $250,000 not accounting for the lost revenue associated with unscheduled plant downtime. This is the value of reliable, data-driven inspections of power plant utility assets in highly corrosive coal-fired power plants. And, when compared to manual UT inspections with significant investments in scaffolding, this is the value of Gecko.