DIN 86037-2
DIN 86037-2 Loose flanges and welding necks for pipes of copper-nickel-alloys - Part 2: Welding necks
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 10/01/1995
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 10/01/1995