This European Standard specifies the end to end and centre to end dimensions for steel butt welding end valves with connecting dimensions of welding ends in compliance with EN 12627, used in PN and Class designated piping systems. The range of PN is: - PN 10; PN 16; PN 25; PN 40; PN 63; PN 100; PN 160; PN 250; PN 320; PN 400. The range of Class is: - Class 150, Class 300, Class 600, Class 900, Class 1 500, Class 2 500. The range of nominal size is: - DN 8; DN 10; DN 15; 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 1 200. NOTE 1 DN 750 is not applicable to PN designated valves. NOTE 2 See Annex B for the relationship between nominal size (DN) and nominal pipe size (NPS). NOTE 3 Valves having welding end profiles different from those specified in EN 12627, may use the same dimensions than those specified in Table 1.