Corrosion Causes of Heating Coil in Oil Storage Tank and Improvement Suggestions

Regarding the frequent corrosion leakage of heating coils in crude oil storage tanks, the reasons for corrosion failure of heating coils at the bottom of the storage tanks were analyzed. In order to solve the problem of selecting external anti-corrosion coatings for heating coils, the service condition of heating coils in storage tanks was simulated by salt-pray corrosion test. The appearance, surface roughness and corrosion rate of three anti-corrosion coatings, epoxy resin, inorganic zinc-rich and polyurethane, were studied after salt-spray corrosion. The results show that compared with polyurethane coating and inorganic zinc-rich coating, the surface of epoxy resin coating was smoother, and the surface roughness and corrosion rate were lower, which were 5.9 nm and 9 μm/a, respectively. So the epoxy resin coating is more suitable as an anti-corrosive coating for heating coils, which can extend the service life of heating coils and ensure safe and efficient operation of storage tanks.