Flowline corrosion problems: a case study of Shell Petroleum Development Company, Nigeria
Describes flowline problems inherent in the land and swamp fields. Non-destructive testing - general visual inspection and ultrasonic thickness survey based on the nominal diameter sizes, age category and location of flowlines - was carried out. The readings obtained were used to calculate the percentage weight loss of pipe per metre and deduce the flowline sections that need to be replaced to avoid rupture of the steel pipe or fitting in service, using residual life estimates. The reduction of the wall thickness of the pipes/ fittings is caused by a combination of corrosion initiated by physical deformation anomalies and the presence of corrosive media along the flowline tracks (inside and outside the pipes). Offers new measures to help the company mitigate the various flowline problems.