Schlumberger announced at the 2009 International Petroleum Technology Conference the release of its EM Pipe Scanner electromagnetic casing inspection tool. The new tool combines a slim mandrel with 18 pad sensors that can run through tubing to produce a quantitative scan of the interior surface and thickness of the production casing.
"The unique ability of the EM Pipe Scanner to measure corrosion in production casing without having to pull completion tubing saves customers significant cost," said Zied Ben Hamad, marketing and technology manager, Schlumberger Wireline. "The service provides a first line of defense in flow assurance. It has been used to identify the precise location of generalized tubing corrosion, grooves and splits, and to monitor corrosion rates to optimize remedial action planning."
Schlumberger has successfully completed more than 100 jobs in 11 countries around the world, deploying the tool by wireline, tractor and coiled tubing at well deviations up to 90° degrees. The tool is fluid insensitive, operating in liquid or gas environments.
The EM Pipe Scanner tool makes a high-speed reconnaissance run as it descends into the well. This run is used to identify places of interest where diagnostic scans are made as the tool ascends to produce images that identify the exact severity and nature of the corrosion. In time-lapse mode, the versatile tool can provide corrosion rate estimates, identify casing corrosion behind tubing and determine inner tubular radius behind scale.
The slim 2 1/8-in diameter EM Pipe Scanner tool easily passes through tubing to evaluate casing below the tubing shoe and quantify metal loss in percentage and average inner diameter (ID) of casing ranging from 2 7/8 to 9 5/8-in outer diameter (OD). In double casing strings a continuous log of average casing ID and total metal thickness is recorded.