Coating with high anti-corrosion resistance to acids in constant immersion and with temperatures up to 220 ° C after baking the treated equipment in the oven. Optimal painting cycle for the internal protection of the heat exchangers tube bundles, with application carried out in high pressure with a semi-automatic machine with a range of use for internal tubes with minimum diameter of 19.5 mm (3/4 ”) and maximum from 100 mm (4 “) with length up to 14 mt.