How to use Industrial Pipe Flange Dimensions& Bolt Hole Chart
- Enter International flange standard & pressure rating and adjust the options as needed.
- Run the tool and inspect its results, evidence and limitations.
- Copy or download the result, then verify it against the actual website, source data or business records.
Try a concrete example
Selected DIN EN 1092-1 PN16 DN50 (2") flange: OD 165 mm, bolt circle PCD 125 mm, 4 holes Φ18 mm, paired with M16×65 mm Grade 8.8 stud bolts torqued to 170 N·m. Incompatibility alert: bolt circle differs by 4.3mm from ASME Class 150 (PCD 120.7mm), preventing direct bolting interchangeability!
How to interpret results
Instant multi-standard flange dimensional lookups generate interactive vector face projections with bolt circle patterns and torque recommendations, preventing costly site mismatches and joint leakage.
Frequently asked questions
Why can't ASME Class 150 and EN 1092-1 PN16 flanges be interchanged?
ASME B16.5 and EN 1092-1 follow different standards. For DN50 (2"), ASME Class 150 has OD 152.4mm and PCD 120.7mm, while EN 1092-1 PN16 has OD 165mm and PCD 125mm. The 4.3mm PCD mismatch causes total bolt hole misalignment.
What is Pitch Circle Diameter (PCD)?
PCD is the diameter of the concentric circle passing through the centers of all bolt holes. PCD and hole count must match exactly between mating flanges for bolt insertion.
Why does a DN80 European flange require 8 holes while ASME and JIS require 4?
At DN80 (3"), ASME Class 150 and JIS 10K specify 4 larger bolts, whereas EN 1092-1 PN16 mandates 8 bolts. Sourcing mismatched flanges leaves 4 bolt holes unfastened, causing catastrophic joint leaks.
What are the differences between RF, FF and RTJ flange face types?
Raised Face (RF) concentrates sealing pressure over a raised gasket area; Flat Face (FF) covers the entire flange surface to avoid cracking brittle cast iron or bronze; Ring Type Joint (RTJ) cuts precision metallic ring grooves for extreme pressure/temperature petrochemical service above 10 MPa.