Chemical compatibility above all
Fuels attack elastomers, and three families share the field. NBR copes with ordinary diesel, and nothing more. HNBR, hydrogenated nitrile, covers petrol, diesel, kerosene, fuel oil, ethanol blends up to E85 and biodiesels: it is the seal Reelcraft now fits on its F and FD fuel series. FKM, sold under the Viton trade name, remains the reference for fuels with a high aromatic content and for solvents, and equips the fuel series of several other manufacturers.
The symptom of an incompatible seal is always the same: swelling, loss of elasticity, leakage at the swivel joint after a few months of service. The useful reflex is therefore not to pick the family yourself, but to tell us the fuel actually dispensed and to check the seal published for the exact model: the specification changes over time, and two reels that look identical do not necessarily carry the same seal.
The hose follows the same rule and must carry the compatibility marking corresponding to the fuel actually dispensed.
Static electricity is not a detail
A liquid flowing through a hose generates electrostatic charges, and a fuel is both insulating and flammable. The electrical continuity of the assembly and its connection to earth are therefore safety conditions, not comfort options.
At tanker unloading points, an earthing reel completes the arrangement by connecting the tanker to earth throughout the transfer. It is a separate product, and both are necessary. As soon as the area is classified, the reel must be certified for it: see our ATEX page.
The case of AdBlue
Urea solution is not a hydrocarbon and behaves very differently. It crystallises as it dries and attacks copper, brass and aluminium. A reel intended for AdBlue must therefore exclude these metals in favour of stainless steel — a diesel reel cannot be transposed, despite the proximity of the stations.