Stress Corrosion Cracking and Oil Leakage in a Control Oil Piping System
- 194 Downloads
This article describes the results of an investigation concerning with the failure of a pipe which was carrying oil from the control oil unit to the steam turbine control valves servomotor. The failure was in the form of a crack, propagating horizontally along the pipe. The crack initiated on the outside of the pipe. The cause of the failure was investigated by conducting visual examination, detailed macro and microstructural examinations and determining the composition of material from the failed pipe. The composition of the pipe material was analyzed by atomic absorption spectrometer. The failure of the oil pipe was attributed to stress corrosion cracking. The pipe material is A312 TP 304L. Recommendation to minimize such failures includes coating the pipe to prevent contact with chloride from the surrounding marine environment.
KeywordsControl oil pipe failure Stress corrosion cracking (SCC) Steam turbine Atomic absorption spectrometer
- 1.Needham, N.G., Hudson, R.M., Wilkinson, J., Stone, P.G.: Atmospheric corrosion resistance of stainless steels. Stainless Steels 87, York, UK, paper 26, Institute of Materials, 14–16 Sept, 1987Google Scholar
- 2.Shoji, S., Ohnaka, N.: Effects of RH and chloride type on stainless steel room temperature atmospheric stress corrosion cracking. Corros. Eng. 42, 877 (1993)Google Scholar