... hole and man hole of flange, etc. 2. Petrochemical, chemical, mechanical manufacturer, power station, metallurgy, shipbuilding, medical and pharmaceutical unclear power station and navigation, etc. Spiral wound gaskets ... flange designations: ASME B 16.20, ASME B 16.5, BS1560, ASME B 16.47 A (B), BS EN 1092, DIN, JIS, and NF, etc ...