RGA 75 ( RETRACTABLE GROUNDING ASSEMBLY) Brand : HITACHI

RETRACTABLE GROUNDING ASSEMBLY ( RGA) Comprehensive Lightning Strike Protection for Floating Roof Tanks Effective: Permanent, reliable, low-impedance bond prevents fires triggered by lightning currents Economical: Low initial cost and exceptional return on investment Easy-to-Install: 2 hour install on new and existing tanks Durable: Engineered for years of durability and reliable performance in corrosive environments Low-Maintenance: Requires virtually no upkeep as compared to shunts Award Winning: Winner of the E & P Innovation Award Standards Conformant: The RGA Conforms to both API 545 and NFPA 780 recommendations and is supported by API 545 as a bypass conductor. The APEX approved patented RGA substantially reduces the risk of tank fires by subduing sustained arcs during lightning events and other electrical phenomena. The RGA is able to do this better than other methods, because designers analyzed and found ways to overcome the weaknesses of other, traditional, devices for grounding floating roof tanks. Floating Roof Tank Fires are Common There are 15 to 20 tank fires per year, and over half of them involve Floating Roof Tanks. FRT’ s are especially vulnerable to the direct and indirect effects of lightning. A direct or a nearby lightning strike will cause electrical currents to flow acorss the tank shell and roof. When these lightning currents arc across the roof/ shell interface, they can ignite any flammable vapors that may be present. It is therefore necessary to bond the roof and shell to prevent arcing at the roof-shell interface. Inadequate Protection To combat the risk of rim fires, the industry has been using metal strips called “ shunts” that electrically bond the shell and roof of the tank in multiple locations. Unfortunately, the bond that these shunts establish is unreliable and creates a greater risk of sustained arcs: 1. Rust, waxy product deposits, and paint can line the inner wall of the shell 2. The floating roof can drift slightly offcenter and disconnect some of the shunts from the shell. 3. API Testing proved that shunts will arc under all conditions, even if the tank wall and shunts are new and clean.