Home / Standards / GB 12380.4-90 GB 12380.4-90 PN 2.5 MPa raised face integral ductile iron pipe flange PN2.5MPa凸面整体球墨铸铁管法兰 Standard Type GB ICS N/A CCS N/A Status N/A Issue Date N/A Implementation N/A Responsible Dept N/A Drafting Unit N/A