We have two installations – one with four 50SGs and one with two 34SGs. Both sites have silencers made of Cor-Ten B manufactured by JTK Power. These sites have been commercial for about 1.5 years. We are located in Tallahassee, Florida (a very hot/humid environment).
About six months after commissioning, we noticed large flakes of rust coming out of the stack during engine startups after the engines were shut down for an extended period of time (about a week). Some of the flakes were 6″ x 6″ and .024″ thick.
I submitted a warranty claim with Wartsila and they said the was rust from the manufacturing process – they referred to it as ‘milling scale’. They said it would stop after a year of two of operation, after the Cor-Ten built up a protective layer of rust.
Have any other users experienced this? Do the flakes of rust stop shedding from the stack after a year or two?