Various carbon steel sections of pipework removed from an offshore facility were examined and found to have experienced exceptionally high wall thickness losses as a result of internal degradation. This prompted a case study to determine the mechanisms of degradation which had occurred and to ascertain the reasons why the implementation of corrosion inhibitor provided little protection to certain areas of the pipework. Initially, information for the pipework system was collated relating to the fluid chemistry, sand content, flow rate, temperature, inhibitor usage and pipe geometry. Computational fluid dynamics (CFD) modeling implemented for various regions of the pipework provided an insight into the flow behavior and expected local fluid velocities present.