After a natural gas operator discovered there were no electromagnet acoustic transducer (EMAT) tools small enough to inspect its 10-inch pipeline for stress corrosion cracking (SCC), TDW developed a 10 in. EMAT tool.
EMAT technology was the logical inspection choice for crack inspection. EMAT produces guided sound waves through the entire thickness of the pipe wall. In addition, using EMAT technology does not require a liquid couplant so it avoids post-inspection line-drying, which is required with both hydrostatic testing and a UTCD inline inspection.
According to Sean Moran, TDW EMAT product manager, dzԹTDW was challenged with producing a new tool that would benefit the entire industry. That included miniaturising the electronics, improving data quality, and advancing the functionality from existing EMAT tools.dzԹ
Engineering and production of the smaller model were soon underway. Next came several months of verification at the TDW Salt Lake City, UT, facility. In late April, the tool was successfully run in the operatordzԹs line in the Midwestern United States.
The SpirALL EMAT tooldzԹs magnetic field angle provides a longer range of sensor coverage around the pipe wall. This creates a highly redundant system, which is particularly important for improving sizing accuracy and probability of detection (POD). When the SpirALL EMAT tool is run in combination with the TDW Multiple Dataset (MDS) platform, it enables superior characterization of pipeline defects such as SCC and other interacting threats.
dzԹWe verified the ruggedness of the design, feature detection and sizing capabilities, and pipe navigation abilities of the 10-inch EMAT tool through numerous high- and low-speed pull tests, flow loop tests, sensor wear tests, and temperature and pressure tests,dzԹ Moran said.
The 10 in. EMAT tool was launched inside the operatordzԹs natural gas pipeline on April 20, 2016. It took approximately 12 hours to traverse the 54 km (34 mile) line.
dzԹThe tool performed flawlessly, and the inspection was determined to be a success,dzԹ Moran said. dzԹWith excellent tool performance and data quality, the data analysis team is excited to get started.dzԹ
dzԹWith this new technology, operators who had limited choices for 10 in. diameter crack inspection tools now have a new, validatedoption in this small diameter,dzԹ he adds.
Edited from press release by