De-Rouging Solutions

When stainless steel is welded, an area on either side of the weld is heated nearly, but not quite, to the full melting point of the alloy. This high temperature is still sufficient to allow the different metals that make up stainless steel to move around and reorganize themselves, as well as reacting to form oxides and carbides. In this “heat affected zone” the steel loses much of its corrosion resistance and becomes discolored, usually to blue and/or brown. CitriSurf 8050 is a derouging and passivation product for use on an especially dense and resistant form of corrosion that occurs in pipelines that carry high purity water, WFI, and steam. CitriSurf 8310 is a thicker gel version. Copper sulfate test solution is a surface iron indicator that is accepted as a test for passivation by the industry passivation standards. We supply it as part of a kit or in bulk form.