A European refinery operates a multi-size (8"-10")pipeline, in service since 1956. Made of line pipe, this line has defects attributable to poor welding techniques of the time.
The aim of thiswas to validate previous ILI inspections and provide enhanced accuracy of the true condition of this pipeline using high-resolution . This inspection focused on an API 5L B steel grade pipeline with a of 8.74 to 9.27 mm (0.34 to 0.36 in).
A previous hydrotest and high-resolution, reported several anomalies, such as lack of penetration or incomplete welding. However, a 60 mm (2.4 in) open associated with the was only discovered following an excavation which was found and repaired.
Previously excavated girth welds revealed no, but other typical welding defects however, the wanted to rule out the presence of any -oriented cracks in the or HAZ areas for the entire pipeline.
The remaining two pipeline sections needed to be inspected as well, due to the same metallurgic origin and service parameters.
Therequested full data on the locations and dimensions of any open or initial crack in an expedited timeline.