Steel pipes for use in the oil industry are subject to severe corrosion effects in service. The protection of the internal surfaces of the pipes with glass enamels extends the service life 5-10 times. It should be mentioned that the enameled pipes are not prone to paraffinization, which leads to obstruction and stoppages of the pipelines. A method is proposed for estimation of both the corrosion resistance of glass enamel coatings and service life of new coatings.