Introduction
Flanges are a critical component in any piping system, providing leak-proof joints that allow for easy assembly and disassembly. For medium and low pressure applications (typically Class 150, Class 300, or PN6 to PN40), selecting the right flange involves more than just matching piping dimensions. This article outlines the key technical and procurement considerations to ensure you get reliable, code-compliant flanges for your project.
Standards to Confirm
Before sourcing, verify which design and dimensional standards apply. The most common for medium/low pressure flanges are:
- ASME B16.5: For flanges and flanged fittings (NPS 1/2″ to 24″) – covers dimensions, pressure-temperature ratings, materials, and tolerances.
- ASME B16.47: For larger diameters (NPS 26″ to 60″) – Series A and Series B.
- EN 1092-1: European standard for PN-rated flanges (e.g., PN6, PN10, PN16, PN25, PN40).
- JIS B2220: Japanese standard for flanges.
Always specify the standard and class (e.g.,
