Flanges to EN 1092-1: types, sealing faces and pressure ratings
The flange is the most common detachable connection in piping construction. EN 1092-1 governs dimensions, designs and pressure ratings – here are the key points for the right selection.
The common designs
- Weld-neck flange – butt-welded to the pipe, the most robust solution for high pressures and temperatures.
- Blind flange – seals off a line or a branch tightly.
- Loose flange with collar – the flange rotates freely on a collar, practical when aligning the bolt holes.
- Threaded flange – screwed onto a threaded pipe, without welding.
Sealing strips and sealing faces
The form of the sealing face must match between the connected flanges. Form B1 (flat sealing strip) is common; in addition there are raised faces, tongue and groove or male-and-female faces for higher requirements. The matching gasket (flat, spiral wound, with inner and outer ring) is selected to suit pressure rating, temperature and medium.
PN pressure ratings
EN 1092-1 covers pressure ratings from PN 2.5 to PN 400. For water and general lines PN 10 and PN 16 are usual, for process and steam lines PN 25 to PN 40, and considerably more in the high-pressure range. Hole pattern, flange diameter and thickness are standardised for each pressure rating – only then do flanges from different suppliers fit together.
Materials and certification
Flanges are available in carbon steel (e.g. P250GH/C22.8), creep-resistant grades (16Mo3, 13CrMo4-5) and stainless steel. For safety-relevant applications we supply the inspection certificate 3.1 to EN 10204 on request.
Frequently Asked Questions
Which flange types are covered by EN 1092-1?
Among others weld-neck flanges, blind flanges, loose flanges with collar and threaded flanges – depending on pressure, temperature and assembly situation.
Which pressure ratings does EN 1092-1 cover?
EN 1092-1 covers pressure ratings from PN 2.5 to PN 400. In piping construction, PN 10, PN 16, PN 25 and PN 40 are the most common.
Do you need exactly these parts?
Grade, size, pressure rating and quantity are enough – you usually receive your quote the same day, with an inspection certificate 3.1 on request.
Request a quote