corrosion

Steel corrosion processes that occur due to the effects of the biochemically treated water in coke quenching plenums have been studied. Model investigations into the processes of the corrosion failure of carbon St. 3 steel and alloyed 18Х1MF  steel were carried out to study the behavior of the  metal exposed to the action of the primary but treated water used for the coke quenching after the metal is heated to 373 K and 773 K.

Due to economic trends in the building industry, the investigation of the residual bearing capacity of reinforced concrete elements has been receiving more and more attention in recent years. Studying the effect of damage on the bearing capacity of reinforced concrete elements is one of the main themes of investigation in this field. Results of 4 reinforced concrete beams’ testing are proposed, one of which was the control one (tested without damages) and three- typically damaged in the compressed zone at different load levels.

Reinforced concrete structures are often subjected to various negative environmental influences, reducing their reliability and durability. Main engineering tasks include extension of their life cycle, assessment of durability, reliability and residual service life. This requires reliable assessment of existing damages due to negative environmental impacts. Deterioration of RC structures is complex issue, which should be considered with the account of various factors.

It has been showed that food additives E451 and E459 inhibit corrosion in neutral water-salt medium and additives E316, E631, E621, E631+E551, herbs and spices increased it up to 1.75 times. Under microbial corrosion condition, inducted by sulfate-reducing bacteria, inhibition action (up to 80.9%) was discovered only for additive E459. Other studied additives increased microbial corrosion up to 2.27 times. The presence of food additives in corrosive medium influences the quantity of sulfate-reducing bacteria in biofilm on steel surface.

Analysis of the efficient complex application of zinc coatings such as sherardizing on tubing surface and carbon dioxide inhibitors during the natural gas extraction on Lutsenkivske gas condensate deposit wells has been carried out. Microstructural and electrochemical investigations of zinc diffusion layer have been conducted. Existing industrial experience shows that the complex corrosion protection significantly increases the life of wells, which significantly increases the economic performance and prevents environmental pollution.

It is proposed to use plant and animal raw materials to produce corrosion inhibitors of oil refining equipment. The corrosion inhibitors based on vegetable oil and animal fat with di- and triethanolamine have been synthesized, nitrogen-containing corrosion inhibitors have been obtained, their physical and chemical parameters have been determined. By using the gravimetric method the protective effect of the received inhibitors was determined on St20 steel in a two-phase corrosive environment simulating the preliminary preparation conditions of oil at electro-salting and dehydration plants.

The presence of fatigue cracks on the surface of metallic underground pipelines sharpens the problem of calculation values of strength characteristics at the action of corrosive environments, that did not find the complete decision nowadays. In this connection it is needed to correct the row of defects and normative and technical documents related to insufficient actuality of corresponding.

It was established that natural and Ca modified zeolite inhibit steel corrosion in the medium of low acid rain. The Ca-containing zeolite inhibit the steel corrosion in the most effective way. The protective effectiveness of the alkyd coatings filled with zeolites can be placed in the following order:  unmodified < with natural zeolite < with Ca-containing zeolite.  Встановлено, що природний та модифікований кальцієм цеоліти інгібують корозію сталі в середовищі слабкокислих дощових опадів. Найефективніше інгібує корозію сталі Ca-вмісний цеоліт.

The inhibitory action of nitrogen- and oxygen-containing inhibitors has been investigated by impedance spectroscopy using commercial Armco iron in 0,1 M solution of hydrochloric acid with butanol. The mechanism of blocking effect of the studied compounds has been determined. Методом імпедансної спектроскопії досліджено захисні властивості інгібіторів корозії з нітроген- та оксигенгрупами на промисловому варіанті заліза Армко в 0,1 М розчині соляної кислоти з бутанолом. Визначено механізм блокувального ефекту досліджуваних речовин.