What is EN 1092-1?
EN 1092-1 is the European dimensional standard for circular steel flanges, covering PN-designated pressure ratings from PN2.5 to PN400 in nominal sizes DN 10 to DN 4000.
Key Takeaways
- EN 1092-1 scope: Eleven flange types identified by number, from Type 01 plate flange and Type 11 weld neck through Type 05 blind, with facing forms A, B1, B2, C, D, E and F, and material groups covering carbon, stainless and alloy steels.
- Size range: DN 10 to DN 4000, with DN 15 to DN 600 covering most process work.
- Ratings: PN6, PN10, PN16, PN25, PN40, PN63, PN100, PN160, PN250, PN320 and PN400.
- Material grades: P250GH, P265GH and P280GH carbon steel, 1.4301 / 1.4307 / 1.4401 / 1.4404 stainless, and 1.4462 duplex.
- Kalp Alloys manufactures to EN 1092-1 in Ahmedabad, India, with EN 10204 3.1 and 3.2 certification issued in its own name.
- Third-party inspection by SGS, BV, TUV or Lloyds can be witnessed at our plant before dispatch.
What EN 1092-1 governs
EN 1092-1 is the European dimensional standard for circular steel flanges, covering PN-designated pressure ratings from PN2.5 to PN400 in nominal sizes DN 10 to DN 4000.
Eleven flange types identified by number, from Type 01 plate flange and Type 11 weld neck through Type 05 blind, with facing forms A, B1, B2, C, D, E and F, and material groups covering carbon, stainless and alloy steels.
Scope, sizes and ratings at a glance
The envelope below is the practical reference: what to state on a purchase order so the item that arrives is the item the line needs.
| Parameter | Detail |
|---|---|
| Size range | DN 10 to DN 4000, with DN 15 to DN 600 covering most process work |
| Ratings | PN6, PN10, PN16, PN25, PN40, PN63, PN100, PN160, PN250, PN320 and PN400 |
| Material grades | P250GH, P265GH and P280GH carbon steel, 1.4301 / 1.4307 / 1.4401 / 1.4404 stainless, and 1.4462 duplex |
| Designation system | PN — nominal pressure in bar |
| Size designation | DN — nominal diameter in millimetres |
| Common process ratings | PN6, PN10, PN16, PN25, PN40 |
| Typical facing | Form B1 raised face on process work |
| Weld neck type number | Type 11 |
| Blind type number | Type 05 |
| Interchangeable with ASME B16.5 | No — different bolt circles and bolt counts |
The point buyers most often get wrong
PN and Class are different systems and do not convert cleanly. PN16 is not Class 150 and PN40 is not Class 300 — the bolt circles, bolt counts and outside diameters differ, so a PN-rated flange and a Class-rated flange of nominally similar rating will not bolt together. On plants built to mixed practice this is the most common cause of a flange arriving on site and not fitting.
What Kalp Alloys manufactures to EN 1092-1
Kalp Alloys is a manufacturer, not a stockist. Production runs at our own facility at 5, Jay Vijay Industrial Estate, B/h. Akash Vikas Estate, Keval Kanta Road, Rakhial, Ahmedabad, which means the heat number stamped on the part traces to our own melt record and the mill test certificate is issued in the name of Kalp Alloys.
That matters on standard-led purchasing more than anywhere else, because an approved-vendor submission or a code-governed line has to show who made the part. A certificate passed down a trading chain names a mill the buyer has no relationship with and cannot query.
Grades supplied against EN 1092-1 cover P250GH, P265GH and P280GH carbon steel, 1.4301 / 1.4307 / 1.4401 / 1.4404 stainless, and 1.4462 duplex. Non-standard bores, thicknesses, drilling patterns and facing finishes are produced to customer drawing.
Ordering against EN 1092-1
State the dimensional standard, the size or NPS range, the rating or schedule, the facing where applicable, the material specification and grade, the quantity, and the certification level required. A quotation is typically returned within 24 hours.
Drawings for non-standard items can be sent by email or on WhatsApp at +91 81608 73937 and are reviewed by the technical team. Stock sizes dispatch in three to seven days; made-to-drawing items carry a firm lead time quoted at order confirmation. There is no minimum order on stock sizes and trial quantities are accepted.
Frequently Asked Questions
EN 1092-1 is the European dimensional standard for circular steel flanges, covering PN-designated pressure ratings from PN2.5 to PN400 in nominal sizes DN 10 to DN 4000.
DN 10 to DN 4000, with DN 15 to DN 600 covering most process work. Ratings covered are PN6, PN10, PN16, PN25, PN40, PN63, PN100, PN160, PN250, PN320 and PN400.
P250GH, P265GH and P280GH carbon steel, 1.4301 / 1.4307 / 1.4401 / 1.4404 stainless, and 1.4462 duplex.
No. They are close in pressure terms at ambient temperature but dimensionally different. The bolt circle diameter, number of bolts and outside diameter do not match, so a PN16 flange will not bolt to a Class 150 flange.
Type 11 is the weld neck flange in the EN numbering system. Type 01 is a plate flange, Type 02 a loose plate flange, Type 05 a blind and Type 12 a hubbed slip on.
Yes. Kalp Alloys manufactures to EN 1092-1 at its own facility at 5, Jay Vijay Industrial Estate, B/h. Akash Vikas Estate, Keval Kanta Road, Rakhial, Ahmedabad, and issues the EN 10204 3.1 or 3.2 mill test certificate in its own name rather than passing through a third-party mill certificate.
An EN 10204 3.1 mill test certificate as standard, stating the ordered standard, grade and heat number, with chemical and mechanical results and a dimensional inspection report. EN 10204 3.2 with third-party inspection by SGS, BV, TUV or Lloyds is arranged where the project requires it.