Robotic Inspection of Variable Diameter Pipeline in Illinois
PipeCrawler™
Pipe Diameter: 24" to 36"
Pipe Type: PCCP
Distance Inspected: ~4 miles
Service: PipeCrawler™ - Remote Field Transformer Coupling (RFTC)
Challenge
In 2006, PPIC performed a challenging condition assessment on a four mile section of a 36-inch PCCP line for a large water utility in Illinois. This particular pipe section could not be dewatered and, furthermore, contained seven reducers that changed the pipeline diameter from 36-inches to 24-inches. For optimal data collection, RFTC inspection tools typically need to be configured relative to a pipe’s diameter, therefore the presence of the reducers posed a serious challenge for the inspection team.
Solution
PipeCrawler™ is a tethered, remote-controlled, all-wheel-drive vehicle that can travel up to 4000 ft. within a pipeline. It was developed to facilitate the inspection of smaller diameter pipelines of which a manned inspection would be difficult, as well as to inspect pipelines that are not fully dewatered.
To overcome the challenge of the reducers, a PipeCrawler™ unit was retrofitted with a remote-controlled, extendable mast. This allowed for the PipeCrawler™ to pass the reducers without compromising data quality, and without adding additional access points.
Conclusions
During the inspection data was collected for 1,378 individual pipes. A total of seven reducers were encountered and successfully passed with the use of the extendable mast. All of the data collected was of excellent quality and revealed distress in a number of the client’s pipes. The video feedback displayed how PipeCrawler™ successfully retracted the extendable mast to cope for the repeated change in diameter.
In addition to enabling the PipeCrawler™ to pass through reducers, the extendable mast can also aid passing through certain valves, lines with multiple diameters, therefore simplifying the unmanned inspection process.
Related Topics