Authors: Zаmaddin Allakhverdiyev Zаmaddin Allakhverdiyev | Latifa Kazimova Latifa Kazimova
Source: ETM Equipment Technologies Materials (article, 2025-11-22)
Field: Materials Science — Materials Chemistry

CORROSION PROTECTION ASSURANCE IN THE CONSTRUCTION AND OPERATION OF TRUNK PIPELINES The term corrosion originates from the Latin word “corrosio”, meaning erosion or degradation. Metal corrosion refers to their deterioration and becoming unserviceable as a result of chemical, electrochemical, or biochemical effects. Due to the reduction of the free energy of a construction material, metals exhibit thermodynamic instability. In essence, corrosion can be defined as the destruction of metals and alloys under the influence of the external environment. In some metals, the degradation process occurs not only on the surface but also within the material. This leads to the disruption of the crystal lattice structure and results in the loss of intrinsic properties. When impurities are abundant within the metal, galvanic couples may form on the surface, leading to localized points of attack and the development of pitting corrosion, which accelerates metal degradation. The economic damage caused by corrosion across different countries can be illustrated by several examples. According to Le Metayer, in 1953 the economic loss to Norway due to corrosion amounted to 180 million marks. In 1964, damages to France’s marine structures reached 80 million francs. Every year, biological corrosion results in a loss of 25 million dollars in Australia and 5 million dollars in New Zealand. In the United States, biofouling in the shipping industry causes an annual loss of 10 million dollars, while sulfate-reducing bacteria in underground pipelines cause damages estimated between 500–2000 million dollars annually. To protect the famous Eiffel Tower from corrosion, 70 tons of special paint and varnish are applied every three years. Generally, the surfaces of metals in their normal state and after corrosion differ significantly. However, certain types of corrosion are invisible to the naked eye. This phenomenon, known as intergranular corrosion (metal embrittlement), occurs due to the disruption of the crystal lattice structure of metals. Corrosion of metals is observed under various environmental conditions such as water, atmosphere, soil, acidic, and alkaline media. The electrochemical corrosion process occurs as a result of the formation of a double electric layer at the metal–environment interface. In some cases, chemical effects are accompanied by physical degradation, which is termed erosion–corrosion or fretting–corrosion. In the case of iron and its alloys, rusting occurs as hydrated corrosion products are formed from oxides. Non-ferrous metals also corrode, although they do not form rust. During the design and construction of pipelines, the protection of pipeline structures and foundations of pipes from environmental impacts must be ensured. Keywords: pipeline, metal, environment, protective coating, corrosion Corrosion ; Pipeline transport ; Damages ; Cathodic protection ; Galvanic corrosion ; Galvanic cell Material Properties and Failure Mechanisms ; Corrosion Behavior and Inhibition ; Hydrogen embrittlement and corrosion behaviors in metals