Raw materials of the insulated rail joints
Insulated rail joints, commonly referred to as fishplates, serve as specialized fasteners for linking rail ends together. These components are meticulously crafted in factories through thermal processes, ensuring that insulation materials envelop all metallic elements to guarantee electrical isolation. In China, their production adheres to the national standard GB11265-89. Typically, they are forged from materials like ordinary carbon steel hot-rolled Q235-A, Q255-A, or QT400-18, while some are crafted directly from composite materials.
The classification based on materials reveals:
Q235: Steel composition (according to smelting analysis) falls below or equals 15kg/m and exceeds 15kg/m.
In terms of models, they must comply with the regulations of Q235-A (or Class 3B steel) and Q255-A in GB700, or type 4B steel, respectively.
Among various insulated fishplates, a notable type stands out, constructed from high-strength, alkali-free glass fiber-impregnated epoxy resins, fabricated using high-temperature forming dies. The alkali-free glass fiber's design and mechanical calculations ensure its resilience, featuring direct yarn and continuous felt in assorted configurations. These insulated fishplates undergo rigorous mechanical and electrical performance assessments in the factory, with only qualified products leaving the premises. Presently, railway component manufacturers in China have adeptly mastered this technology.
