Flanged connection valve

Flange-connected valves are manufactured in accordance with the national standards of the People’s Republic of China, GB/T 9112~9124-2010. These standards cover 13 types of flanges, including integral, necked threaded, and butt-welded types, suitable for various welding processes and structural requirements. The technical specifications utilize a dual pressure rating system based on PN and Class; PN encompasses 12 grades ranging from 2.5 to 400, while Class includes 6 grades from 150 to 2500. National standard flanges have strict requirements regarding dimensional tolerances and material specifications; only qualified steel materials must be used to ensure mechanical properties and welding reliability, distinguishing them from non-standard products that may use smaller dimensions or inferior materials. The related standard GB/T 12221—2005 specifies the structural dimensions of flange-connected valves, covering a diameter range of DN3 to 4000mm and pressure levels below 42.0MPa. It also outlines the measurement methods for various connection types, such as straight-through and angle-type connections. Flanges are available in different connection formats, including FF (flat face), RF (raised face), and RTJ (ring joint type). The technical specifications are compatible with international standards such as EN and ASME, and these valves can be used for various types of valves, including gate valves, globe valves, and ball valves.

Tags: valve