High Pressure

PTFE Backup Rings: Anti-Extrusion Retainers for Aerospace Hydraulic and Pneumatic Systems
Engineering reference for PTFE backup rings (packing retainers): extrusion mechanics, single versus double configurations, cut geometry, and the MS28774, MS28782, MS27595, AS5781 and AS8791 specifications.
O-Ring Back-Up Rings: Anti-Extrusion Design
When to use O-Ring back-up rings, how they stop extrusion, and single versus double back-up arrangements for high-pressure glands.