CSNRI Europe Ltd. had a team of technicians already working on site at a refinery when a routine inspection revealed external atmospheric corrosion on a 711-mm (28-inch) carbon steel line carrying butane.
A length of 1.6 m (5 ft) of line was severely corroded, resulting in extensive wall thinning. The line was designed for 12.26 bar (178 psi) pressure and 145ºC (293ºF) and was operating at 81ºC (178ºF).
The traditional solution for repairing the line was to use a clamp, but the extent of the damage meant the repair would require a clamp weighing nearly two metric tons.
The CSNRI engineering team evaluated the details of the line damage and designed a composite solution. The thin-walled state of the line meant surface preparation would not be possible on the corroded area. This led to the decision to use ThermoWrap MT, which is particularly well suited for repairing high-temperature and process piping.