Home / Standards / GB/T 18691.4-2011 GB/T 18691.4-2011 Abolished Agricultural irrigation equipment - Irrigation valves - Part 4: Air valves 农业灌溉设备 灌溉阀 第4部分：进排气阀 Standard Type GBT ICS 65.060.35 CCS B91 Status 废止 Issue Date 2011-05-12 Implementation 2011-10-01 Responsible Dept 中国机械工业联合会 Drafting Unit N/A