... DN15-DN2000 3.Standard:ANSI,ASTM,MSS,JIS,DIN,EN HY carbon steel Welding Neck Flange We started to product ... Used forpetroleum, chemical, power, gas, water, linepipe, heat exchanger, shipbuilding, construction, etc .6. Production processraw material--cutting--heating--forging--heat treatment--maching ... depends on your quantity11.Supply Capacity700 tons per month HY carbon steel Welding Neck Flange