DIN 14330:2012-05

Type C delivery couplings according to this standard serve for the connection of semi-rigid delivery hoses according to DIN EN 1947 with an internal diameter DN - 25 mm (fire-fighting hose DIN EN 1947 - I - A - 1 - 25 - 20 - 30) and - 33 mm (fire-fighting hose DIN EN 1957 - I - A -1 -33 - 20 - 30). This standard also gives the former internal diameters (DN) 28 mm and 32 mm for the former semi-rigid delivery hoses S 28 and S 32 according the withdrawn DIN 14817-1 which are, however, no longer intended for new design. The gasket consists of mineral-oil resistant materials. In order to ensure that in practice couplings from different manufacturers can be interconnected easily, it would have been preferable from the users' point of view to also include the specified torque values for the coupling in the scope of testing. It is not possible to put this test into practice for the time being as for this purpose a normal coupling shape is necessary which has, in contrast to a coupling with gasket, a metallic sealing surface and consequently specifies other coupling torques than those when two gaskets are interacting. Nevertheless, the values for the torques during coupling are contained in the draft standard and specified for the manufacturing of couplings. They are not part of the test, however. Destructive tests are not generally common in valve engineering. Therefore, reference is made in clause 7 of the standard to the technical delivery conditions for valves according to the DIN EN 12266 standard series. The highest compression stress reasonable for a coupling is determined by the gasket anyway. A burst pressure test, for example, for delivery hoses is therefore not necessary for couplings. The following modifications have been made with respect to DIN 14330-1:1985-04 and DIN 14330-2:1985-04: a) standard parts have been combined; b) internal diameters DN have been changed from 32 mm to 33 mm and from 28 mm to 25 mm; c) existing internal diameters S 28 and S 32 are no longer intended for new designs; d) material specifications including surface treatment have been revised; e) type and control tests have been replaced by conformity tests (verification); f) marking has been revised; g) content has been revised, editorially and with regard to standards, including the normative references. The standard has been prepared by Working Committee NA 031-04-04 AA "Schläuche und Armaturen - SpA zu CEN/TC 192/WG 1 und WG 8" ("Hoses and hose fittings (Mirror Committee of CEN/TC 192/WG 1 and WG 8)") at DIN.