Blind Flange (ASME B16.5 & DIN)
Engineering definition, metallurgical mechanisms, standard testing specifications, and manufacturing guidelines for closed-die forgings up to 50 kg.
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A solid circular forged disk with bolt holes but no central bore, used to terminate the end of a piping run, valve nozzle, or pressure vessel inspection opening.
Technical Explanation & Metallurgical Principles
Blind flanges (BL) undergo higher bending stress than any other flange type because internal fluid pressure exerts force across the entire face of the solid plate. Manufactured in closed dies strictly up to 50 kg, forged blind flanges possess radial grain flow that eliminates central lamination defects found in plate-cut alternatives.
Key Engineering Specifications & Parameters
| Technical Parameter / Metric | Engineering Benchmark / Value |
|---|---|
| Bore | Solid (Zero bore) |
| Pressure Class | Class 150# to 2500# (PN 10 to PN 400) |
| Stress Profile | Maximum bending stress at the center face |
Application at Jayesh Forge (Rajkot Plant)
Drop-forged in Rajkot from ASTM A105, A350 LF2, SS 316L, and Duplex 2205 strictly up to 50 kg for high-pressure oil, gas, and steam isolation.
Related Materials, Standards & Products
Applicable Material Grades
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.
Raised Face (RF Flange Facing)
A raised annular gasket sealing surface elevated 1/16" (1.6mm) or 1/4" (6.4mm) above the flange bolt hole circle.
Weld Neck Flange (WN Flange)
The premier high-integrity forged flange configuration featuring a long, tapered circular hub that butt-welds seamlessly to process pipe.
Questions Regarding Blind Flange (ASME B16.5 & DIN)
Forged blind flanges have seamless continuous grain flow around bolt circles and zero risk of mid-thickness laminar tearing under cyclic pressure surges.
Request a Forging Quote with Blind Flange (ASME B16.5 & DIN) 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.