FIELD: chemistry; electricity.
SUBSTANCE: invention relates to electrochemical protection of metals from corrosion and can be used for protection of underground metal structures in aggressive medium, in particular for protection of pipelines in water supply, gas and oil industry. Method involves feeding a sequence of current pulses to a protected metal surface of a defined amplitude and duration at a given range of protective potential of the protected surface, wherein values of duration and amplitude of pulses are determined as follows: pulse duration is varied at initial value of 2.5 % duty cycle and minimum amplitude value equal to direct current value providing value of preset range of potential of protected surface, at that, constant measurement of current potential of protected surface is carried out and its comparison with specified range of potentials, change of pulse duration is continued to obtain value of filling factor ≥ 80 %, then amplitude of pulses is increased and when current potential value of protected surface is reached above limit value in specified range, pulse duration is reduced to obtain value providing potential within specified range, then obtained values of duration and amplitude of pulses are maintained. Range of potential of the protected surface is set from minus 0.85 V to minus 1.1 V.
EFFECT: technical result is providing optimum value of electric energy consumed during protection of underground structures.
1 cl, 2 dwg
