The article is concerned with the current problem of restoring the required performance of water pipelines of public water supply systems. The effectiveness of using trenchless pipe rehabilitation technologies is noted. The article analyzes the results of the experiments for determining the strength characteristics of Scotchkote® 2400 protective corrosion resistant coating of pipes that were carried out in the laboratory of the Water Supply and Sanitation Department of the Moscow State University of Civil Engineering with Instron 3345 electromechanical tensile testing machine. The effectiveness of Scotchkote® 2400 protective coating relative to restoring and improving the strength and hydraulic characteristics of worn water pipelines was shown. The author comes to the conclusion that Scotchkote® 2400 protective coating is a substantial alternative to cement-sand and other internal coatings, since in many respects it surpasses them owing to the ability of colmatage sealing of large diameter holes; high wear resistance; smooth surface; ability to endure high hydraulic pressures. The coating does not overlap service connections and slightly reduces the diameter of the restored pipelines. Based on the studies, comparative characteristics of Scotchkote® 2400 protective coating spraying technology with the basic methods of trenchless pipeline reconstruction are presented.
Mathematical processing of the results of experimental studies of the physicomechanical characteristics of Scotchkote®2400 coating is given. As a result of the studies, the calculated values of the protective coating thicknesses for partially worn and completely worn out pipelines are obtained and recommended.

100% humidity and the presence in the air of such corrosion stimulants as CO2, NH3 and H2S are characteristic of livestock buildings. Under these conditions, a surface phase film of moisture is formed on the surface of the metals in which the indicated micro-mixtures of air are dissolved and hydrated almost completely with the formation of NH4OH and acids H2CO3 and H2S. The potentiodynamic polarization method was used to study the corrosion and kinetics of electrode processes on steel with a superhydrophobic coating in a NaCl background solution (used to provide sufficient electrical conductivity) saturated in pairs with CO2 and NH3, NH3 and H2S. Similar studies were conducted with uncoated electrodes. Superhydrophobic coating was obtained on the basis of laser texturing of the surface with subsequent hydrophobization with fluoroxysilane (wetting angle 165±2°, rolling angle 3±1°). The influence of the duration of the exposure of the electrodes in solution (0,25…168 h) on the kinetics of electrode processes and the corrosion rate of steel is considered. In the presence of CO2 and NH3 dissolution products, the corrosion rate of an electrode with a superhydrophobic coating on the second and third days of exposure is about an order of magnitude, and on the fourth and seventh days it is more than an order of magnitude lower than without coating. During the entire time the electrodes are in solution, the anode process on the superhydrophobic electrode is inhibited compared to an unprotected electrode. The medium containing the dissolution products of NH3 and H2S is more aggressive than the previous solution. Therefore, the corrosion rate of the electrodes without coating and with a coating here is higher than in the latter one. The corrosion rate of electrodes with superhydrophobic coating in the study period is only 1,5…2,5 times lower than that of uncoated electrodes. During the first day of exposure, the anode process is inhibited, and in the next 144 hours, on the contrary, it is facilitated in comparison with an unprotected electrode. Taking into account the corrosivity of the chloride solution, the possible effect of the dissolution products of aggressive air micro-impurities in the absence of background salt was analyzed

The bactericidal properties of the combined inhibitor with respect to two types of Desulfovibrio desulfuricans and Desulfomicrobium sulfate-reducing bacteria were studied. The effect of the inhibitor on the number of bacterial cells and the formation of hydrogen sulfide in Postgate nutrient Postgate “B” was evaluated. It has been shown that the combined inhibitor exhibits a bacteriostatic effect on to sulphate-reducing bacteria.
It was revealed that the degree of suppression of the number of microorganisms Desulfovibrio desulfuricans at a concentration of the combined inhibitor 100,0 mg/L is higher than Desulfomicrobium. In the latter case, to achieve this effect, 120,0 mg/L concentration of the combined inhibitor is required.
The studied combination inhibitor causes the inhibition of hydrogen diffusion in steel St3 in the MI medium saturated with H2S and CO2 separately and together, and also contributes to preserving the ductile properties of the steel St3 after exposure to solutions compared to non-inhibited media

It is known that the disadvantages of ferrosilide earthing devices are their fragility, which leads to their frequent mechanical damage. Their fragility is increased with increasing silicon content. The solution to this problem is to reduce the content of silicon in the alloy, but this greatly increases the rate of dissolution of the resulting alloy. As a result, the possibility of reducing the dissolution rate of ferrosilides with a silicon content of 9…12% due to thermal oxidation and treatment in a phosphoric acid medium was studied. The most promising method for anode grounding conductors is the method of processing materials in orthophosphoric and metaphosphoric acids with the formation on the surface of a phase of iron silicide highly resistant to anodic dissolution due to selective etching of the alloy. The relationship between the phase composition of the films showed that mainly phases of silicon oxide (SiO2) and magnetite (Fe3O4) predominate in the alloys, as a result of which the dissolution rate is significantly reduced. As a result of heat treatment of ferrosilide alloys with a silicon content of less than 14%, a decrease in the dissolution rate does not occur due to the high porosity of the formed films and the presence of phases that do not have protective properties. The anodic dissolution rate is the lower, when the grain size of the alloy used is the larger.

The formation of corrosion products in the surface layers of steel 15KH12VNMF brand was investigated in solutions of hydrochloric, sulfuric, phosphoric, and nitric acids. Comparative data were obtained on the accumulation of impurity alloying elements in surface layers of high-alloy steel 15KH12VNMF brand. The content of alloying elements was defined in the surface layer of steel and corrosion products when holding samples in solutions with a certain concentration for 1 hour. The obtained data indicate that the accumulation of manganese, molybdenum and nickel in the surface layer does not occur in the sulfuric acid solution. The surface layers in the solution of phosphoric acid accumulate intensively alloying impurities, whereas in nitric and hydrochloric acids there is a selective accumulation. The surface films on the steel 15KH12VNMF brand in solutions of hydrochloric, sulfuric, phosphoric, nitric acids were Identified at high concentrations and times of incubation. It was established that the rate of manganese accumulation in hydrochloric acid is constant, regardless of the acid concentration. For nickel and molybdenum, the rate of accumulation increases at initial concentrations, and tends to its constant value at high concentrations. In sulfuric acid solutions, the amount of manganese on the surface depends not only on the concentration, but also on the holding time. The accumulation of nickel and molybdenum on the surface of the plate depends as on the concentration and the time. It was determined that in solutions of phosphoric acid the accumulation of manganese occurs only at the primary time, in the future remains constant. The accumulation of nickel and molybdenum on the surface depends as on the concentration and the time and has a similar character. The data are obtained that the accumulation of manganese, nickel, molybdenum on the surface of the sample in solutions of nitric acid with increasing concentration occurs regardless of the holding time of the sample

The developed IPC-CorrMeter software is intended for studying corrosion of metals, alloys, and coatings and estimating the efficiency of anti-corrosion protection by emulating the operation of a “Corrosimeter” device in potentiostats of the IPC series that allows implementing well-known and reliable corrosion-electrochemical methods, such as linear polarization resistance, zero resistance amperometry, and potentiometry in the existing serial IPC potentiostats. The advantages of the new software include: a possibility of continuous automatic use of these methods in the study of corrosion processes, obtaining results almost in real time mode, high sensitivity and a wide adjustable range of measurements of the rates of general and pitting corrosion (from 1 nm to tens of mm per year), no absence of any restrictions regarding the RAM size of the device. Quantitative dependences of the general and pitting corrosion rate of steel St3 in water are obtained in the presence of the industrial СARTEС-28B corrosion inhibitor for hydraulic testing of mud pumps. They confirm the reliability, accuracy, high sensitivity, and validity of the IPC-CorrMeter software and equipment for researching metal corrosion and allow evaluating the efficiency of anti-corrosion protection agents, as well as the high efficiency of this inhibitor