Anti Extrusion PTFE Rubber Backup Rings For Hydraulic Fluids

PTFE Anti-Extrusion Backup Rings — Fluid Compatibility and Grade Specification

A PTFE backup ring supports an O-ring at the clearance gap in a specified static or dynamic gland. Select ring geometry and construction against the groove drawing and installation method.

For fluid compatibility review, identify the exact hydraulic fluid, additives, cleaning agents and contact temperature. Virgin and filled PTFE grades require their own material data; a general PTFE description does not establish suitability for every fluid or assembly pressure.

PTFE Grade Requirements
Virgin PTFE hardness reference: 55 Shore D; confirm grade, test method and acceptance range.

Solid, scarf-cut and spiral constructions are separate order options. Specify the ordered form and check assembly access, ring thickness and groove fit.

Material range:

Virgin PTFE: specify compression, creep and dimensional stability requirements for the actual operating load and temperature.

Filled PTFE: identify glass, graphite, carbon or bronze filler and its content. Review both chemical exposure and contact with mating surfaces before approval.

Provide the AS568 O-ring dash number and gland drawing with backup ring dimensions, PTFE grade, quantity and required material documentation.

Define operating pressure direction, peak pressure and the maximum extrusion gap under load. Include groove width, O-ring squeeze and temperature for complete assembly review.

When replacing damaged seals, identify the fluid in service and any swelling, wear or extrusion observed. Check mating-surface condition and clearance rather than selecting only by the removed ring dimensions.

Review O-ring compound, hardness and support-ring geometry together. PTFE formulation changes require material and fit approval; rubber support rings are separate alternatives with their own compound requirements.

Locate support on the low-pressure side for a defined pressure direction. For reversing pressure, review support on both sides and the groove space required using the assembly drawing.

NBR or FKM 90-durometer backup rings are separate rubber options; confirm hardness scale and compound. PTFE hardness references use Shore D and should not be replaced by rubber Shore A values.

Contoured support rings require a section drawing and separate material specification.

Related Rubber and Oilfield Components

Rubber O rings:

1) Standard O-Rings

Sizes: AS568 dash sizes or metric dimensions with specified tolerances.

Materials: NBR, silicone, FKM, HNBR or EPDM by specification; food-contact requirements need compound documentation.

Color: Black, Brown, or custom color.

2) Custom rubber o rings, X rings, or kinds of seals and washers&gaskets.

Custom parts are quoted against an approved drawing or sample with mating dimensions.

Specify shape, color and hardness requirements on the part drawing.

Hammer union seals

Rubber union seals with or without brass or stainless-steel backup rings; fit by assembly specification.

Available Material: NBR, FKM, HNBR.

Nominal union sizes: 1, 1.5, 2, 3 and 4 inches; seal dimensions by assembly drawing.

Plug seals

Available Material: NBR, FKM, HNBR ect.

Nominal size references: 1, 2 or 3 inches; plug seal fit by assembly drawing.

Dust Seals or Swivel Dust Seals

Oil saver rubbers

Pipe wipers

Swivel Ball Plugs

Thread Protectors

Related product photographs for reference; identify the ordered ring by drawing:

Additional related product photographs:

Send fluid designation, additives, operating temperature and exposure duration with your PTFE backup ring enquiry. Include the gland drawing, grade and filler requirements, pressure direction and quantity; specify any compatibility test and acceptance criteria before ordering.