Home / Standards / GB/T 12221-2025 GB/T 12221-2025 Active Metal valves—Face to face, end to end, centre to face and centre to end dimensions 金属阀门 结构长度 Standard Type GBT ICS 23.060.01 CCS J16 Status 现行 Issue Date 2025-10-31 Implementation 2026-05-01 Responsible Dept 中国机械工业联合会 Drafting Unit N/A