Raised Face (RF Flange Facing)
Engineering definition, metallurgical mechanisms, standard testing specifications, and manufacturing guidelines for closed-die forgings up to 50 kg.
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A raised annular gasket sealing surface elevated 1/16" (1.6mm) or 1/4" (6.4mm) above the flange bolt hole circle.
Technical Explanation & Metallurgical Principles
The raised face (RF) concentrates the entire bolt clamping load onto a confined annular gasket area, generating immense contact pressure that ensures a leak-free seal. In ASME B16.5, Class 150# and 300# flanges have a standard 1/16" (1.6mm) raised face, while Class 400# through 2500# flanges feature a heavy 1/4" (6.4mm) raised face.
Key Engineering Specifications & Parameters
| Technical Parameter / Metric | Engineering Benchmark / Value |
|---|---|
| Class 150# / 300# RF Height | 1/16 inch (1.6 mm) |
| Class 400# to 2500# RF Height | 1/4 inch (6.4 mm) |
| Gasket Contact Roughness | 125 – 250 µin Ra (serrated finish) |
Application at Jayesh Forge (Rajkot Plant)
The primary flange facing manufactured across all our 56 standard ASME and DIN flange lines up to 50 kg max piece weight.
Related Materials, Standards & Products
Engineered Product Lines
Related Metallurgical & Testing Terms
ASME B16.5 Pipe Flanges Standard
The definitive American standard covering pressure-temperature ratings, materials, dimensions, tolerances, marking, and testing for pipe flanges NPS 1/2 through NPS 24.
Flange Facing Serrated Finish (Serrated Spiral / Concentric)
The standardized micro-groove surface finish machined onto the raised face of a flange to bite into sheet or spiral-wound gaskets under bolt compression.
Ring Type Joint (RTJ Flange Facing)
A specialized flange facing featuring a precision-machined trapezoidal ring groove engineered to seat an octagonal or oval solid metallic ring gasket.
Questions Regarding Raised Face (RF Flange Facing)
In ASME B16.5, the 1/16" raised face of Class 150# and 300# is included in the minimum thickness (C), but for Class 400# and higher, the 1/4" raised face is additional to the catalog thickness.
Request a Forging Quote with Raised Face (RF Flange Facing) Compliance
Our Rajkot metallurgy desk is ready to review your technical drawings, testing protocols, and delivery schedules for custom closed-die forgings strictly up to 50 kg.