Selected Answers

From David Grove of Shaw Nuclear Power Services on October 28, 2010:
Your question does not define the stage of yo ...read more Your question does not define the stage of your project or the exposure conditions. This response is based on severe exposure. If still in fabrication, order the steel coated with coatings that meet slip critical criteria. Most inorganic zinc-rich coatings meet this requirement. If bolts are not High Strength (HS), then order them either coated or galvanized. If they are HS, which are generally covered with black millscale, then the best method to prep these, after installation, is blast to SSPC- SP 10 since this removes the millscale and preps the difficult to access surfaces such as the threads, gaps, edges of washers, etc. Power tool cleaning is acceptable, but inspections must ensure that all those difficult to prep surfaces are correct for the coatings that will follow. Depending upon installation methods, oils may be present; therefore, SSPC-SP 1 may be required before surface prep. This work is difficult and can be slow. Ensure a fair contract to a qualified contractor and inspection company. SSPC can help with this by their qualification programs.