FIELD: protection of steel petroleum and gas production equipment from corrosion and corrosive mechanical disintegration. SUBSTANCE: corrosion inhibitor comprises condensation product consisting of compounds based on imidazolines and monoamides, more specifically mixture of 1-diethylenediamino-2-alkyl(alkylene)-2-imidazolines, monoamides such as alkyloyl (alkylenoyl) triethylenotetramines and 1,4-dialkyloyl (alkylenoyl) piperazines at imidazoline to monoamide weight ratio of (2.7- 3.0):1, respectively, and degree of unsaturation of condensation product of 34-50 mg J2/100 g. Inhibitor is prepared by condensation of mixture containing high molecular weight synthetic fatty acids and polyethylene polyamine. Condensation process is carried out in stages when heating is performed in three stages and temperature rises successively in three stages and temperature is maintained after each stage in the presence of concentrated hydrochloric acid as catalyst. The present invention makes it possible to increase effectiveness of protection of petroleum and gas production equipment from corrosion when it is used in various aggressive media. EFFECT: improved properties of the corrosion inhibitor. 11 cl, 2 tbl
