EN1092-1 TYPE11 1.4404 Weld Neck RF Flange

EN 1092-1 This is the European standard for steel flanges, defining types, dimensions, materials, and pressure ratings. It is comparable to ASME B16.5 in the U.S.

Under EN 1092-1, Type 11 designates a "Hubbed Welding Neck Flange". This type features a tapered hub for reinforcement, making it suitable for high-pressure applications. It differs from Type 05 (standard welding neck) by having a distinct hubbed design for enhanced strength.

Weld Neck Indicates the flange is welded to the pipe via a long tapered hub, ensuring smooth stress distribution and durability in demanding conditions.

RF (Raised Face): A typical flange face type (EN 1092-1 uses Type B for raised face).

FF (Flat Face): Designated as Type A in EN 1092-1.

1.4404 is a stainless steel grade standardized under EN 10088-3 (European standard for stainless steels). It is the low-carbon (L-grade) version of the popular austenitic stainless steel 1.4401 (equivalent to AISI 316). Here’s a detailed breakdown:

Use in Flanges (EN 1092-1):

1.4404 is not commonly used for standard EN 1092-1 flanges, which typically use carbon steel (e.g., P265GH) or higher-grade stainless steels (e.g., 1.4301/304).

It may be specified for specialized corrosive service conditions (e.g., chemical pipelines, marine applications).

Key Difference from 1.4401 (316):
Lower carbon content (≤0.030% vs. ≤0.07% in 1.4401) minimizes carbide precipitation during welding, making 1.4404 ideal for welded components.

EN 1.4404 / AISI 316L Chemical Composition

Application Of ASME B366 C276 Flange

• Oil and Gas Industries

• Food Processing Industries

• Equipments

• Pipeline

• Power Industries

• Ship Building Industries

• Paper Industries

• Cement Industries

• Chemical Industries