Introduction
Aerospace applications demand extreme reliability. Flanges used in fuel systems, hydraulic lines, and propulsion test stands must withstand high pressures, temperature swings, and vibration without failure. For procurement engineers, specifying the correct aerospace-grade flange is not just about dimensions—it’s about ensuring traceability, material integrity, and compliance with industry standards.
This guide provides a practical checklist for sourcing flanges for aerospace use, from standards and materials to inspection requirements and RFQ best practices.
Key Standards to Confirm
Before issuing an RFQ, verify that the flange design follows an accepted standard. The most common for aerospace are:
- ASME B16.5 – Covers pipe flanges and flanged fittings for nominal pipe sizes NPS ½ through NPS 24, with pressure classes 150 to 2500.
- ASME B16.47 – Larger flanges (NPS 26 through 60) used in ground support equipment.
- SAE AS series – For specialty aerospace flanges, such as AS4395 (O-ring face seal flanges) or AS5202 (port connections).
