Flanges by standard
EN 1092-1 PN flanges for European data centers
European data centers specify flanges by PN rating to EN 1092-1. We make the common types in stainless and carbon steel, under a quality system certified by TÜV Rheinland for the Pressure Equipment Directive.
For a European data center, the usual flange is EN 1092-1 PN16, Type 11 weld neck or Type 01 plate flange, Form B1 raised face, in stainless steel on the CDU and TCS side and carbon steel on the facility side.
Flange types
| Type | Name | Typical data center use |
|---|---|---|
| 01 | Plate flange for welding | Low pressure chilled and condenser water; economical |
| 02 | Loose plate flange | With a weld-on collar or lapped pipe end on stainless lines |
| 05 | Blind flange | Header ends, future connections, test points |
| 11 | Weld neck flange | Pump, chiller and CDU connections; stainless secondary loops |
| 12 | Hubbed slip-on flange | General water piping where fillet welds are accepted |
Facing is defined separately. Type A is a flat face for cast iron, plastic and other flat-faced equipment. Type B1 is the standard raised face for steel-to-steel joints with flat gaskets.
PN ratings
PN is a reference designation, close to the allowable pressure in bar at room temperature for the reference material. The allowable pressure for a given material depends on its material group and the temperature, as tabulated in EN 1092-1. Water loops in data centers run cool, so PN16 covers most chilled water and facility water systems, with PN25 used for high static heads and some pump discharges.
A PN16 flange does not bolt to an ASME Class 150 flange in most sizes. Where a European plant has American-built chillers or CDUs, check the equipment nozzle standard and order flanges to match each side.
Materials
We supply EN 1092-1 dimensions in the stainless and carbon steel grades on our stainless and carbon steel pages. Tell us the EN material grade on your specification and we will confirm it at quotation.
Pressure Equipment Directive
RIC holds a TÜV Rheinland certificate for its quality assurance system as a manufacturer of materials under Directive 2014/68/EU, Annex I point 4.3, tested to EN 764-5 clause 4.2 and AD 2000-Merkblatt W0. The scope covers flanges, fittings, forged bars and seamless pipes. For European fabricators building CDUs, skids or plant to the PED, this provides the material certification that Annex I point 4.3 requires for main pressure parts in categories II to IV. See our certificates.
Frequently asked questions
Which PN rating is usual for European data center chilled water?
PN16 is the common choice for chilled water and facility water in European data centers. PN10 appears on low pressure condenser water, and PN25 where static head or pump pressure is higher.
Do EN 1092-1 and ASME B16.5 flanges bolt together?
Generally not. Bolt circles and bolt sizes differ between PN and Class flanges for most sizes. Where a European project has American equipment, specify transition flanges drilled to each side.
Why does a PED certificate matter for EN 1092-1 flanges?
For main pressure parts of equipment in PED categories II to IV, Annex I point 4.3 of Directive 2014/68/EU requires a certificate of specific product control from a material manufacturer whose quality system is certified by a competent body in the EU. Our quality system is certified by TÜV Rheinland for exactly that.