Stress Corrosion Cracking (SCC) Has No Borders

摘要

Despite all the hype about Near Neutral pH and High pH (Classical) SCC, there are no borders that separate these threats as some people have speculated. A classical or high pH SCC failure first occurred in the mid 1960s on a high-pressure gas transmission pipeline that was located in Natchitoches, LA. The result of this failure was a natural gas release, explosion and fire with several fatalities. Conversely, near neutral (transgranular) SCC occurred in the mid 1980s in Canada. This type of corrosion exhibits transgranular morphology and has been known to have corrosion on the pipe surface associated with it. Whereas high pH SCC, which tends to have tighter cracks, typically does not have corrosion associated with it.