CAM & CNC Gasket Engineering Tool
Flange & Gasket PCD Bolt Circle Calculator
Calculate Pitch Circle Diameter (PCD), chordal hole-to-hole spacing, inner/outer ligament wall widths, sealing surface area, and standard bolt hole clearances for CNC oscillating knife, laser, and waterjet gasket fabrication.
1. Flange & Gasket Dimensions
2. Calculated Concentric PCD & Ligament Specs
Chordal Pitch (Hole-to-Hole)
107.76 mm
4.243 in
Angular Hole Spacing ($ heta$)
90.0°
Equal Division
Outer Margin Ligament ($L_{out}$)
9.55 mm
Wall to OD
Inner Margin Ligament ($L_{in}$)
22.25 mm
Wall to ID
Total Sealing Surface Area
212.4 cm²
32.92 in²
Ligament Integrity Risk
Safe (>6mm)
Blowout Protection
CONCENTRIC GASKET & PCD BOLT PATTERN PREVIEW
Need Precision Gasket Vector DXF / SVG Files from Scans or Photos?
Tracing greasy, worn paper gaskets or scanned flanges with calipers is tedious and prone to misalignment. SpotItLive converts your bitmap photos and scans into mathematically concentric DXF toolpaths with exact PCD concentricity, zero segment distortion, and knife lead-in optimization.
Compatible with Zünd, Atom, Gerber, FlashCut, Flow Waterjet, LightBurn & AutoCAD
Engineering Reference: ASME B16.5 & EN 1092-1 Flange Bolt Standards
Concentricity and minimum ligament width are critical to prevent gasket blowout under hydrostatic fluid pressure.
| Nominal Size | Standard | Flange OD | PCD | Bolt Count ($N$) | Hole Dia ($d_h$) | Min Ligament |
|---|---|---|---|---|---|---|
| 2" Class 150 | ASME B16.5 | 152.4 mm (6.00") | 120.7 mm (4.75") | 4 | 19.0 mm (3/4") | 6.35 mm (0.25") |
| 3" Class 150 | ASME B16.5 | 190.5 mm (7.50") | 152.4 mm (6.00") | 4 | 19.0 mm (3/4") | 9.55 mm (0.38") |
| 4" Class 150 | ASME B16.5 | 228.6 mm (9.00") | 190.5 mm (7.50") | 8 | 19.0 mm (3/4") | 9.55 mm (0.38") |
| DN50 PN16 | EN 1092-1 | 165.0 mm | 125.0 mm | 4 | 18.0 mm | 11.0 mm |
| DN100 PN16 | EN 1092-1 | 220.0 mm | 180.0 mm | 8 | 18.0 mm | 11.0 mm |
| DN150 PN16 | EN 1092-1 | 285.0 mm | 240.0 mm | 8 | 22.0 mm | 11.5 mm |
Core Prepress Rules for Gasket Vector DXF Toolpaths
- Oscillating Knife Overcut Mitigation: CNC oscillating tangential knife tables (Zünd, Atom) experience blade deflection. Vector DXFs must include smooth tangential radiused entries (tangent lead-ins) rather than abrupt 90° corners on bolt holes.
- True Arc Geometry (G02/G03): Do not approximate bolt circles with faceted polylines (which create ragged polygon holes). Ensure all circular features are exported as true DXF
CIRCLEorARCentities. - Bolt Hole Clearance Margins: Always provide standard ASME bolt clearance ($+1.5 ext{ mm}$ to $+3.0 ext{ mm}$ over nominal bolt shank diameter) to accommodate flange thermal expansion and bolt insertion tolerances.