DIN EN 1267:2012-04

This European Standard specifies a method for determining valve pressure loss coefficient and fluid flow coefficient using water as test fluid. This method is suitable for: valves with low ζ values but higher than 0,1 by determining pressure loss, with respect to fluid flow rate and specific gravity; and for valves with equal inlet and outlet nominal size. Industrial process control valves are excluded from this European Standard. For ζ values above 6, the pressure loss coefficient inaccuracy is higher than the pressure loss caused by the test tubes. It becomes the same configuration of tests as in EN 60534-2-3. If using air as test fluid, other standards, for example, EN 60534-2-3 and ISO 6358 should be referred to. This document (EN 1267:2012) has been prepared by Technical Committee CEN/TC 69 "Industrial valves", the secretariat of which is held by AFNOR (France). This document supersedes EN 1267:1999. The main changes compared to the previous edition are the following: a) the scope was specified and editorially revised; b) the normative references were updated; c) clause 3 on terms and definitions was revised; d) clause 4 on test facility was changed; e) clause 5 on test procedure was changed; f) Annex A on lower limit considerations for ζ was revised; g) Annex D on evaluation of uncertainty of flow rate coefficient (K_ny) and pressure losses coefficient (ζ) was added; h) a bibliography was added.