The case study demonstrates different approaches towards what went wrong and why on pressure safety valve susceptible to MIC growth. The Eocene Sub Centre-1 Shipping Pump discharge header connected pressure safety valve (01PSV172) reported leaking from the body and POD requested Asset Integrity Division to conduct Root Cause Analysis with recommendation.
In this work, the open circuit potential of different stainless steel grades as well as nickel based and copper based alloys has been systematically measured in seawater under different experimental conditions. In particular the effect of temperature, oxygen content and chlorination level have been studied.
Superduplex stainless steels have been used in seawater systems since 1986 as castings and since 1990 as wrought product. The present paper describes some of the service environments commonly in use and the conditions that give rise to specific operating potentials. The limits of use under these conditions are described utilizing both laboratory and service experience.