There are 15 to 20 known floating roof tank (FRT) fires per year. 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 across 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.
Substantially reducing the risk of sustained arcs requires a reliable, full-time, low impedance and low-resistance connection between the tank shell and roof. Additionally, the connection must operate regardless of the tank shell’s condition.
The RGA is not affected by the condition of the tank because the RGA and cable are bolted and sealed to optimal locations on the tank shell and floating roof. When properly applied, multiple RGAs on each tank provide low-impedance pathways to safely discharge lightning currents.
The RGA is designed to retrofit easily onto any existing tank, even those in service and is also easy to inspect and is constructed to be low maintenance.
The new RGA 750 uses stronger springs to retract the cable.