When conduit is installed in hazardous locations or corrosive environments, special consideration must be given to the selection of materials. Corrosion poses a massive challenge to the safe operation of industrial facilities and can be characterized as the gradual destruction of materials, usually metals, by chemical reaction with their environments. Corrosion puts the long-term safety and reliability of rigid metallic conduit (RMC) assemblies at great risk. When RMC is installed in harsh environments, the corrosive atmosphere must be considered as a threat to the integrity of the complete installation.
There are two solutions to this problem that can help mitigate the destructive properties of corrosion. PVC Coated conduit begins with either Galvanized Rigid Conduit (GRC) or Rigid Aluminum Conduit (RAC), which is then coated with a specialty formulated 40 mil Polyvinyl Chloride (PVC) coating on the exterior and a 2 mil urethane coating on the interior and threads. PVC Coated “system” includes integral PVC sleeves that overlap and seal all threaded joints to ensure the integrity of the installation. Calbond™, a division of Calpipe Industries, Inc., manufacturers a full line of PVC coated conduit and fittings that meet the industries highest standards of corrosion resistance, as well as being compliant with NEC® requirements for hazardous locations.
A second solution is the integration of stainless steel conduit raceways. Calbrite™, a division of Calpipe Industries, Inc., now offers a package of stainless steel fittings suitable for use in hazardous locations. Fittings include Unions (Type UNY), Boxes (Type GUA), and Seals (Type EYS). The Calbrite family of stainless steel products for hazardous locations give the electrical professional the highest level of defense against the danger of corrosive destruction.