Corrosion Under Insulation (CUI) and Fastener Selection

Keywords: Corrosion, insulated fasteners, chemical plant

In industrial settings like refineries, fasteners hidden under insulation are prone to a severe threat: Corrosion Under Insulation (CUI). Trapped moisture and temperature cycles create a perfect environment for rust. Specifying the right material is vital. Stainless steel fasteners (e.g., 316 SS) or specially coated bolts are often required to withstand this hidden, aggressive environment, preventing unexpected failures in pipes and vessels.