ISO 7005 and EN 1092 cover PN-classified, round flanges for pipes, valves, plain fittings and accessories, plus their dimensions and tolerances, categorized according to different types of materials.
Both standards also contain the assignment of pressures and medium temperatures.
The connecting dimensions, flange and face types plus descriptions conform to the relevant ISO 7005 standards.
ISO 7005, part 1: Steel flanges
ISO 7005, part 2: Cast iron flanges
ISO 7005, part 3: Flanges made of copper alloys
Since the valves covered by this document are used throughout the world, the international standard ISO 7005 was selected as a basis. The information given below explains the differences between ISO 7005 and EN 1092.
EN 1092: Part 1,
steel flanges
The international standard ISO 7005-1 on steel flanges was used as a basis for the development of EN 1092. EN 1092 deviates from ISO 7005 in the following ways:
It solely covers flanges with PN designation
A number of technical requirements of flanges originating from DIN standards have been changed
The differences between EN 1092-1 and ISO 7005-1 are as follows:
In many cases, the pressure-temperature assignments of this standard have been reduced, either by limiting the assignments at lower temperatures – which may no longer exceed the value of the PN class – or by increasing the rate at which the admissible pressure drops on temperature rise
In addition to the PN 2.5 – PN 40 range of flanges originating from DIN standards, which is defined in ISO 7005, EN 1092 also contains flanges up to PN 400
EN 1092: Part 2,
cast iron flanges
In terms of flanges of the same PN class, this standard refers to ISO 7005-2 and ISO 2531. Flange types and connecting dimensions are compatible with the same DN and PN class of ISO 7005 and ISO 2531.
Pressure-temperature assignments: There are no differences between EN 1092-2 and ISO 7005-2
EN 1092: Part 3, flanges made of copper alloys
In terms of flanges of the same PN class, this standard refers to ISO 7005-3. Flange types and connecting dimensions are compatible with the same DN and PN class of ISO 7005.
Pressure-temperature assignments: There are no differences between EN 1092-3 and ISO 7005-3
To be able to make use of the permissible operating pressures and operating temperatures according to EN 1092-1 as listed in the following tables/graphs, high-quality steel is required when using steel flanges.
Otherwise, the permissible plant operating pressures must be reduced as specified in EN 1092-1.