EN 1092-1 is the harmonized European standard for steel flanges, published by CEN. It effectively supersedes DIN 2501, DIN 2527–2693, and the British BS 4504. EN 1092-1 is the authoritative flange standard for the EU market and is widely adopted internationally. It covers 12 flange types across pressure ratings from PN 2.5 to PN 400 and sizes from DN 10 to DN 4000.
View Other Standards:
DIN 2545 Weld Neck JIS B2220 BS 4504 DIN 2527 Blind
EN 1092-1 — European Steel Flange Standard PN 2.5 – PN 400
EN 1092-1 is the harmonized European standard for steel flanges, effectively superseding DIN 2501, DIN 2527–2693, and BS 4504. It is the authoritative standard for the EU market and is widely adopted internationally. Covers DN 10 to DN 4000, PN 2.5 to PN 400.
EN 1092-1 — Flange Types Overview
| Type |
Description |
Key Application |
| Type 01 |
Plate Flange (for welding) |
Slip-on / lap joint connections |
| Type 02 |
Loose Flange (with collar) |
Corrosion-resistant collar + loose plate |
| Type 04 |
Loose Flange on collar |
Similar to Type 02, different geometry |
| Type 05 |
Blind Flange |
System closure / isolation |
| Type 11 |
Weld Neck Flange |
High-pressure, high-temperature, cyclic |
| Type 12 |
Weld-on Collar (for loose flanges) |
Welded collar + removable plate |
| Type 13 |
Weld Neck Collar |
High-pressure collar connection |
| Type 21/22/23 |
Socket Weld Flange |
Small bore, high-pressure |
| Type 32/33 |
Threaded Neck Flange |
No-weld assembly (BSPT bore) |
Table 1: EN 1092-1 flange types (selection of most common types). For full type listing, refer to EN 1092-1:2002+A1:2012.
Key Specifications
Standard: EN 1092-1:2002+A1:2012
Pressure: PN 2.5 / 6 / 10 / 16 / 25 / 40 / 63 / 100 / 160 / 250 / 320 / 400
Size: DN 10 – DN 4000
Face Types: Flat Face (FF), Raised Face (RF), RTJ, Tongue & Groove
Supersedes: DIN 2501, DIN 2527–2693, BS 4504
Annexes: Form B1 (RF), Form B2 (T&G), Form D (RTJ), Form E (FF)
EN 1092-1 Type 01 (Plate) — PN 10 Dimension Table
| DN |
Pipe OD (mm) |
Flange OD D (mm) |
Thickness b (mm) |
Bolt Circle k (mm) |
Bolt Holes |
Hole d (mm) |
Approx. Weight (kg) |
| 10 |
17.2 |
90 |
12 |
60 |
4 |
14 |
0.52 |
| 15 |
21.3 |
95 |
12 |
65 |
4 |
14 |
0.61 |
| 25 |
33.7 |
115 |
14 |
85 |
4 |
14 |
1.20 |
| 50 |
60.3 |
165 |
16 |
125 |
4 |
18 |
2.85 |
| 80 |
88.9 |
200 |
18 |
160 |
8 |
18 |
4.95 |
| 100 |
114.3 |
220 |
18 |
180 |
8 |
18 |
5.80 |
| 150 |
168.3 |
285 |
20 |
240 |
8 |
22 |
10.80 |
| 200 |
219.1 |
340 |
22 |
295 |
12 |
22 |
17.60 |
| 300 |
323.9 |
445 |
26 |
445 |
12 |
22 |
34.20 |
| 400 |
406.4 |
565 |
28 |
515 |
16 |
26 |
59.40 |
| 500 |
508 |
670 |
30 |
620 |
20 |
26 |
91.20 |
| 600 |
610 |
780 |
32 |
725 |
20 |
30 |
134.0 |
Table 2: EN 1092-1 Type 01 Plate Flange — PN 10 dimensions. Reference: EN 1092-1:2002+A1:2012. Full table covers DN 10–DN 4000.
EN 1092-1 Pressure-Temperature Ratings
| PN |
20°C |
100°C |
200°C |
250°C |
300°C |
350°C |
400°C |
450°C |
| PN 6 |
6 |
5.5 |
5.0 |
4.8 |
4.5 |
— |
— |
— |
| PN 10 |
10 |
9.2 |
8.2 |
7.5 |
7.0 |
6.2 |
5.5 |
— |
| PN 16 |
16 |
15.0 |
13.5 |
12.5 |
11.5 |
10.0 |
9.0 |
— |
| PN 25 |
25 |
23.2 |
20.5 |
18.8 |
17.5 |
15.5 |
14.0 |
12.0 |
| PN 40 |
40 |
37.0 |
33.0 |
30.0 |
28.0 |
24.5 |
22.0 |
18.0 |
| PN 64 |
64 |
59.0 |
52.5 |
48.0 |
44.5 |
39.0 |
35.0 |
28.5 |
| PN 100 |
100 |
92.0 |
82.0 |
75.0 |
70.0 |
61.0 |
55.0 |
45.0 |
| PN 160 |
160 |
147 |
131 |
120 |
112 |
98 |
88 |
72 |
Table 3: EN 1092-1 allowable pressure (bar) by PN class and temperature (°C). Values based on P245GH / 13CrMo4-5 group 1 materials.
Face Type Forms
| Form |
Face Type |
Description |
| Form B1 |
Raised Face (RF) |
Standard raised face, 2–5 mm height. Most common. |
| Form B2 |
Tongue & Groove (T&G) |
Male/female sealing surfaces for precision alignment. |
| Form D |
Ring Type Joint (RTJ) |
Grooved face for high-pressure / high-temperature service. |
| Form E |
Flat Face (FF) |
Full face contact, used with full-face gaskets. |
| Form F |
Spigot & Recess |
Spigot face / recess for O-ring seal. |
Table 4: EN 1092-1 face type forms (Forms B1, B2, D, E, F per Figures 4 and 11 of the standard).
Materials (EN 1092-1 Material Groups)
| Group |
Material |
Grade |
Max Temp |
| 1E1 |
Carbon steel |
P250GH (1.0460) |
300°C |
| 1E2 |
Carbon steel, fine grain |
P265GH (1.0425) |
350°C |
| 2E1 |
13CrMo4-5 (1.7335) |
13CrMo4-5 |
500°C |
| 2E2 |
10CrMo9-10 (1.7380) |
10CrMo9-10 |
550°C |
| 5E1 |
X2CrNi18-9 (1.4306) |
304L |
400°C |
| 5E2 |
X2CrNiMo17-12-2 (1.4404) |
316L |
400°C |
| 5E3 |
X2CrNiMoN22-5-3 (1.4462) |
Duplex 2205 |
300°C |
Table 5: EN 1092-1 material groups and maximum design temperatures. Material must be selected to match both pressure and temperature requirements.
Applications
EU and international oil & gas pipeline projects (mandatory CE marking territory)
Petrochemical and chemical processing plants
Power generation and nuclear installations
Water and wastewater treatment facilities
Shipbuilding and offshore platforms
Food, pharmaceutical, and hygienic process lines
While PN classes between DIN, EN, and BS standards are dimensionally equivalent, ANSI/ASME pressure classes (150, 300, 600, etc.) are not dimensionally identical to PN classes for all DN sizes. Bolt hole counts, bolt sizes, and flange OD may differ. Always check dimensional compatibility before mixing standards in the same joint assembly.
Flange Material Selection Guide
| Material |
Grade |
Max Temp |
Key Application |
| Carbon Steel |
P250GH / A105 |
425°C |
Steam, water, oil, gas |
| Stainless Steel 316 |
A182 F316 |
400°C |
Chemical, food, pharma |
| Stainless Steel 316L |
A182 F316L |
400°C |
Weld-intensive fabrication |
| Duplex 2205 |
A182 F51 / S31803 |
300°C |
Offshore, seawater |
| Super Duplex 2507 |
A182 F53 / S32750 |
300°C |
Harsh chemical, subsea |
| Alloy Steel F22 |
A182 F22 (2¼CrMo) |
550°C |
Power plant, refineries |
| Inconel 625 |
UNS N06625 |
700°C |
Aerospace, marine |
Table 6: Material selection guide for EN 1092-1 steel flanges. Always verify with applicable pressure equipment code.
HT PIPE manufactures EN 1092-1 flanges in all types (01, 02, 04, 05, 11, 12, 13, 21-23, 32-33) in carbon steel, stainless steel, duplex, and special alloys. All flanges supplied with EN 10204 3.1/3.2 material test reports and dimensional inspection certificates.
