GB/T 12226-2005

This standard specifies the technical requirements, test methods, inspection rules, and marking for flake graphite iron castings used in general purpose industrial valves. It is applied in the manufacturing and quality control of valve bodies, bonnets, and other pressure-containing components for fluid systems such as water, steam, and non-corrosive media in industries like municipal water supply, HVAC, and low-pressure pipeline systems. The standard ensures casting integrity, mechanical properties, and pressure-tightness for valves operating at temperatures typically up to 200°C and pressures up to 1.6 MPa.