Welded flange production standards: Because Vessel nominal diameter and nominal pipe diameter depending on the specific dimensions represent, therefore, the same nominal diameter of the vessel flange and pipe flange, which is not the same size, both can not substitute each other. In addition to the type of pipe flange welding, butt welding flange, there are steel flanges, cast iron flanges, Looper flange, threaded flange. Except GB9119.7-88 standard pipe flanges, the common standards are: Ministry of Chemical Industry Standard HG20592 ~ HG20602-97; Sinopec standard SH3406-96 like. Ministry of Chemical Industry standards which are divided into the European system, the Inter-American system, and our common European system. Since the operating pressure is not high, small diameter, can be welded flange influenza, flat sealing surface, asbestos rubber sheet gasket material selection. Coupling bolts selection of materials for the Q235-A, the choice of 2 ", 4" flange. Flange material: carbon steel, mainly 20 # steel, Q235 material. Packing: fumigation wooden pallets can be according to customer requirements for special packaging. Product Quality: ISO9001: 2008 quality management system certification, ISO14001 environmental management system certification, OHSAS18001 occupational health and safety management system, pressure pipe special equipment manufacturing license, the State Power Corporation, China National Petroleum Corporation a supply network members supply range flange : petroleum, power plants, chemical, gas, fire, water, sewage pipes, steel mills, shipyards.