Short answer: TB/T 2809-2026 (Electrified railway overhead contact system - Copper alloy contact wire) took effect on 1 September 2026, replacing TB/T 2809-2017. Three key changes: the pure copper contact wire grade is removed; copper-tin and copper-magnesium grades are revised; and a copper-chromium-zirconium (CTCZ) grade is added for high-tension, high-reliability catenaries.
Impact on sourcing
Tender documents should reference the 2026 edition. Existing lines designed around pure copper wire do not require immediate replacement; new builds and renewals should select among copper-silver (CTA/CTAH), copper-magnesium (CTM/CTMH), copper-tin (CTS) and copper-chromium-zirconium (CTCZ). Stranded wire standards are now split into TB/T 3111.1-2026 and TB/T 3111.2-2026.
Related products
Copper-silver contact wire | Copper-magnesium contact wire | CuCrZr contact wire