Backup rings are designed to prevent extrusion in rubber o-ring sealing systems. There are three basic types of PTFE back-up rings in use: single turn (scarf cut), multiturn (spiral cut), and solid (uncut) configurations. Our backup rings are made from either one of two materials, PTFE or rubber. Rubber backup rings are called contoured backup rings. The material of choice for rubber contoured rings is 90 durometer nitrile.
PTFE BACKUP RING STYLES
Online Data Table
TF74C / TF74S
Single Turn / Solid Extended Series
CONTOURED BACKUP RINGS
Contoured backup rings were developed primarily for service in petroleum based hydraulic fluids, at -4°C to 121°C (-40°F to 250°F). The standard 90 durometer nitrile product, provides the maximum benefits in backup ring service. Compounds for use in other fluids and for temperatures up to 204°C (400°F) are available.
Contoured backup rings will stretch up to 50%, and are quickly and easily installed. Advantages of the contour design are obtained regardless of how the contoured rings are installed – they may be installed with the concave face in either direction, toward or away from the o-ring.
Available in all AS-568 sizes. Contact us contoured backup rings.