About structural elements of polymer insulators of the contact network

Abstract

The high load on electrified lines makes tougher the requirements for the reliability and maintainability of power supply devices. Insulators are a critical element of the overhead contact network, and great attention is paid to improving their characteristics — electrical and mechanical strength. Advantages of polymer insulators in comparison with traditional ones made of porcelain and glass are generally recognized: manufacturability, low weight, compactness, ease of installation and transportation, high mechanical strength and shock resistance.The article presents the results of comprehensive studies of the electrophysical characteristics of fiberglass rods and bars made of AG-4S carried out by the University of Railway Engineers (MIIT), which were used in the developed polymer structures of the contact network. Recommendations are given on the maintenance of fiberglass rods and bars from AG-4S and their engineering support. The issues of the mechanical strength of polymer insulators of the overhead contact network are covered quite fully, therefore, this article offers the basic principles for calculating their electrical strength. The main requirements for modern polymer insulators and design features are briefly presented for each type: suspended, tension, cantilever, fixing and supporting.

Keywords

• railway transport
• contact network
• polymer insulators
• types of structures
• reliability
• maintenance