The Retractable Grounding Reel (RGR for short) is designed to discharge the static electricity of floating roof storage tanks. It realizes equipotential connection between the tank shell and floating roof, and provides the lowest impedance channel for the safe discharge of lightning current and bound charge. At the same time, it reduces the instantaneous overvoltage between the floating roof and tank shell, minimizing the possibility of a lightning-induced fire.

The device adopts the design of double coil spring in series, which has obtained the national patent. This design reduces the number of coiled spring working turns while ensuring the product tension, which makes the product's service life more than 10 years.