ISMAILOV, M. UDC 621.565.93/95 INFLUENCE OF SURFACE LAYER THICKNESS ON HYDRAULIC RESISTANCE OF THE DEVICE : Purpose of the work: The increase in the thickness of the scale on the inner surfaces of technological pipes reduces the cross-sectional area of the pipe, thereby decreasing its conductivity. As a result, the coefficient of friction in the pipe increases, which in turn leads to an increase in its hydraulic resistance. This causes a sharp increase in the amount of energy consumed, as the required pump power for fluid transportation rises accordingly. Scientific and Technical Journal of Namangan Institute of Engineering and Technology, [S. l.], v. 9, n. 4, p. 137–141, 2024. DOI: 10.61151/stjniet.v9i4.624. Disponível em: http://niet.uz/index.php/nj/article/view/624. Acesso em: 14 apr. 2025.