This part of ISO 7005 for a single system of flanges specifies requirements for circular copper alloy and composite flanges in the following nominal pressure ratings:Series 1* Series 2*lSO PN10 lSO PN6 ISO PN16 ISO PN25ISO PN20 ISO PN40ISO PN50Attention is drawn to the need to refer to the pressure/temperature (p/T) ratings in tables 10, 10a), 10b) and 10c) for the maximum permissible working pressures and temperatures, particularly for ISO PN20 and ISO PN50 flanges and for ISO PN6, ISO PN10, ISO PN16 and ISO PN25 flanges attached by soft solder or silver brazing.This part of ISO 7005 specifies the types of flanges and their facings, dimensions, tolerances, bolt sizes (including copper alloy), flange face surface finish, marking, testing, inspection and materials.NOTES1 Dimensions of gaskets will be the subject of a future International Standard.2 For guidance, information on the application and installation of flanges is given in the annex, which does not form an integral part of this part of ISO 7005.