Back-up rings are supportive components
that are manufactured with materials that are resistant to
extrusion under pressure. When installed in a recess along with
elastomeric sealing components like o-rings and seals, they
function as protective elements preventing the elastomeric
material of the sealing component from extruding into the
sealing gap under pressure. The cross section of a back-up ring
is generally rectangular, and they are not designed for sealing
Back-up rings are used in external and internal sealing
applications, as in piston seals and rod seals. Material
selection can be of Viton, NBR, HNBR, FKM, and PTFE. Dynamic and
static use, with reciprocating as well as rotating movements are
Typical applications of back-up rings are as supportive
components for lip seals, o-rings and shaft seals that are
commonly found in hydraulic and pneumatic cylinders.
Gmors manufactures o-rings and seals in materials that include
HNBR, Viton, EPDM, Nitrile, NBR and more.
Download back-up ring standard sizes.