Naphthenic acid corrosion behavior of 20 G and Cr5Mo under high temperature

High temperature and high flow rate naphthenic acid corrosion (NAC) simulation device is applied to investigate NAC behavior of 20 G low carbon steel and Cr5Mo steel under various temperature and flushing angle. The results show that temperature and flushing angle could influence the corrosion rate of both steels in naphthenic acid. Under temperature of 240 degree C, 280 degree C and 360 degree C the difference of corrosion rate between flushing angle of 0 degree and 90 degree is less than 20%, but at 320 degree C the difference could reach 46%. Corrosion rate would decrease above 320 degree C due to the decomposition of naphthenic acid. The software of Fluent is applied to simulate the turbulence on the surface of specimens and the results indicate that the areas along the flushing direction of fluid on the specimens of 0 degree and the central regions on the specimens of 90 degree are the places that maximum turbulence and maximum naphthenic corrosion existed, this fact indicate that turbulence influenced N