This standard BS EN 593:2017 Industrial valves. Metallic butterfly valves for general purposes is classified in these ICS categories:
23.060.30 Gate valves
This European Standard specifies minimum general requirements for butterfly valves having metallic bodies for use with all type of pipe end connections (e.g. wafer, lug, flange, butt welding) and used for isolating, regulating or control applications. The PN and Class ranges are: - PN 2,5; PN 6; PN 10; PN 16; PN 25; PN 40; PN 63; PN 100; PN 160; - Class 150; Class 300; Class 600; Class 900. The size range is: - DN 20; DN 25; DN 32; DN 40; DN 50; DN 65; DN 80; DN 100; DN 125; DN 150; DN 200; DN 250; DN 300; DN 350; DN 400; DN 450; DN 500; DN 600; DN 700; DN 750; DN 800; DN 900; DN 1 000; DN 1 050; DN 1 100; DN 1 200; DN 1 400; DN 1 500; DN 1 600; DN 1 800; DN 2 000; DN 2 200; DN 2 400; DN 2 600; DN 2 800; DN 3 000; DN 3 200; DN 3 400; DN 3 600; DN 3 800; DN 4 000. DN 750 and DN 1 050 are used only for Class 150 and Class 300. Intermediate DNs are allowed upon agreement between manufacturer and customer. For valves subject to European legislation on pressure equipment, EN 16668 applies together with this European Standard. For industrial process control valves, EN 1349 and EN 60534 2 1 apply together with this European Standard. For water supply application, EN 1074 1 and EN 1074 2 apply together with this European Standard. NOTE 1 Butterfly valves for water supply application do not comply with Annex ZA and are not CE marked because they are excluded from the pressure equipment European legislation. NOTE 2 The range of DN, applicable to each PN, for wafer and wafer lug valve types is as given in the appropriate part of EN 1092 for Type 11 flanges for the applicable material. The range of DN, applicable to each PN, for flanged valve types is as given in the appropriate part of EN 1092 for Type 21 flanges for the applicable material. The correspondence between DN and NPS is given for information in Annex D.