This European Standard for a single series of flanges specifies requirements for circular steel flanges in PN designations PN 2,5 to PN 100 and nominal sizes from DN 10 to DN 4 000.
This standard specifies the flange types and their facings, dimensions, tolerances, threading, bolt sizes, flange jointing face surface finish, marking, materials, pressure/temperature ratings and approximate flange masses.
This standard does not apply to flanges made from bar stock by turning, or to flanges of types 11, 12 and 13 made from plate material.
Consequently, whilst the mating dimensions, the flange and facing types and designations are compatible with those given in ISO 7005-1, it is important to take account of the following differences which exist in EN 1092-1:
1) The p/T ratings of this standard have been reduced in many cases by either limiting the lower temperature ratings which can no longer exceed the PN value, or by increasing the rate at which allowable pressures reduce with increase in temperature.
2) In addition to the range of PN 2,5 to PN 40 DIN origin flanges contained in the ISO standard, EN 1092-1 also includes PN 63 and PN 100 flanges.
3) This standard specifies grades of European steels similar to those specified in ISO 7005-1, but in addition permits the use of those grades of ASTM steels which are specified in the ISO standard for use with the ANSI/ASME based flanges.
