PRACTICAL EXPERIENCE OF TECHNICAL SURVEY RELIABILITY OF OVERHEAD TRANSMISSION LINE STRUCTURES

Ensuring the reliability of the supporting structures of existing transmission lines is a key aspect of maintaining the stability and efficiency of the energy infrastructure. Various methods and technologies are used for this purpose. This study presents a methodology for comprehensively inspecting the load-bearing structures of overhead transmission lines located in the Aksu city of Pavlodar region of Kazakhstan. The survey included 2 main stages: visual and instrumental inspection up to the moment of line de-energization and inspection of all components of transmission line supports. During the design and construction, special reliability requirements were considered, such as the consideration of engineering-geological conditions when selecting a site for the construction of each support, considering the estimated climatic conditions of the region, wind speed, and the size of ice deposits. The results obtained from the inspection of all main and fastening elements of the supports' structures allowed us to assess the current state of the infrastructure and define a strategy for its maintenance and renewal. The results showed that deviations in metal profile thickness were minimal, averaging +/- 0.5 mm from design specifications, indicating minor structural failure. Grounding device resistance measurements varied within a narrow range of 5 to 7.45 Ohms, which met safety and operational standards, further confirming the reliability of the infrastructure. The strength of the concrete in the foundations, evaluated without failure, averaged 25 MPa, which meets Class B30 standards and indicates environmental resistance, which allowed us to conclude that further operation of transmission lines is possible.