Corrosion is the main cause of equipment degradation in the energy industry. “Green” corrosion inhibitors help to extend the service life of equipment, reducing the need for its frequent replacement or repair, which reduces costs. Effective corrosion protection allows equipment to work at maximum capacity without interruptions, which increases the overall productivity of energy facilities. In this study, the effectiveness of the inhibition of 17GS steel in the NS4 environment was determined by the use of water, water-alcohol plant, oil extracts. When conducting the experiment, the composition and antioxidant activity of the components, as well as the patterns of adsorption behavior and mechanism of action, were taken into account. The relationship between protective properties of inhibitors and chemical transformations of their constituent compounds in environments with corrosive activity was studied by using gravimetric research. It was found that the formation of a protective film on the surface of 17GS steel with the use of plant extracts takes place over a long period of time. Plant extracts are used as volatile atmospheric corrosion inhibitors, and the duration of the process is explained by the formation of a barrier layer by individual compounds and their polycondensation and polymerization products. Evaporation of extracts and adsorption on the metal surface leads to an increase in the thickness of the protective film. The process represents prolonged chemical transformations both on the surface of the metal and in the solution, which, under appropriate corrosion conditions, determines their inhibitory effect. A technological scheme for obtaining plant extracts is proposed, which allows the chemical process of manufacturing a corrosion protection agent to be implemented. Detailed technological recommendations for the use of “green” corrosion inhibitors have been developed. It was established that the maximum inhibition effect (69.0%) is achieved when using a water-alcohol solution of echinacea by forming an oligomeric film on the surface of the metal, which includes molecules of the plant extract and their chemically transformed and oligomeric products. The conducted research allows expanding and clarifying modern concepts regarding the regularities of the formation of protective films on the surface of steel with the participation of plant extracts in a corrosive-aggressive water and atmospheric environment. Research results can be used in the creation of combination mixtures of complex action, as well as scientific approaches to the development of “green” corrosion inhibitors.