RUBRINGS / SELECTION & SUPPLY
Specialist O-ring materials
Compare PTFE, FFKM, polyurethane, fluorosilicone, SBR and natural rubber O-rings. Learn what to specify before selecting a compound.
PTFE O-rings
PTFE is a thermoplastic, not a rubber elastomer. Its limited elasticity makes installation and gland suitability especially important. Do not assume that a PTFE ring can replace a rubber ring in the same groove.
What to put in the brief
Specify whether the design calls for solid PTFE or an encapsulated elastomer, and provide the assembly drawing.
FFKM O-rings
Perfluoroelastomer compounds are considered for demanding chemical or thermal service. Compatibility and performance depend on the specific formulation; FFKM is not a universal upgrade for every application.
What to put in the brief
Give the chemicals, concentrations, continuous and peak temperatures, cleaning steps and required grade.
Polyurethane O-rings
Polyurethane families include different chemistries. A material chosen for mechanical duty still needs review for the fluid, moisture and temperature involved.
What to put in the brief
Name the grade where known and specify movement, loading, temperature and water exposure.
Fluorosilicone O-rings
Fluorosilicone (FVMQ) is distinct from standard silicone (VMQ). Check the specific fuel or fluid as well as the movement and temperature conditions.
What to put in the brief
Record the operating medium, cold-start requirement, seal movement and compound identification.
SBR O-rings
SBR is styrene-butadiene rubber. Treat it as a separate material family rather than an interchangeable substitute for nitrile.
What to put in the brief
Ask for compatibility evidence for the actual medium and include weathering and ageing conditions.
Natural rubber O-rings
Natural rubber (NR) is a distinct rubber family. Its useful mechanical properties do not establish suitability for oil, weather or chemical exposure.
What to put in the brief
Provide the medium, outdoor exposure, mechanical duty and replacement-part specification.
Rubrings is a trading and supply business. Specialist compound availability and documentation need confirmation against each enquiry.
Background: Parker O-Ring Handbook and Trelleborg technical catalogues. These are independent engineering references.
Build your enquiry brief