Tianjin Metro Line 9 introduces first dual-to-single upgraded train, China September 17, 2025 | Asia Pacific News, News The Government of Tianjin has launched the first dual-to-single modified train on Metro Line 9. The upgrade shifts trains from operating on a dual-system setup to a fully single-system platform, bring... This content is available to only subscribers. Username or E-mail Password Remember Me Forgot Password