No matter what industry you’re in, chances are you’ve used (or needed to use) an o-ring. And if you’ve used an o-ring, chances are it was from Parker. That’s because for years Parker has been the industry standard in developing, manufacturing, and supplying high quality o-rings, both standard and customized.
But even if you have extensive experience with this product, there are new developments and breakthroughs happening all the time. Among these developments are the wide array of materials from which Parker o-rings are manufactured. These materials each offer unique specifications to cater to the needs of projects. Here’s an overview of those materials to help you get up to speed:
- Nitrile rubber (NBR) is the general term for acrylonitrile-butadiene terpolymer. The acrylonitrile content of nitrile sealing compounds varies considerably (18 to 50%.) Polymers with higher ACN content exhibit less swell in gasoline and aromatic solvents, while lower ACN polymers exhibit better compression set and low temperature flexibility. This polymer is also called Buna-N.
- Butyl (IIR)
- Butyl rubber (isobutylene-isoprene rubber or IIR) has a very low permeability rate and good electrical properties, but poor short-term rebound.
- Polychloroprene Rubber (CR)
- Also known by the trade name Neoprene®, polychloroprene was the first synthetic rubber and exhibits generally good ozone, aging, and chemical resistance. It has good mechanical properties over a wide temperature range.
- Ethylene Acrylic (AEM)
- Ethylene acrylate is a mixed polymer of ethylene, methyl acrylate and a small amount of carboxylated cure-site monomer. Developed as a lower-temperature version of Polyacrylate; but swells slightly more.
- Ethylene Propylene (EPM, EPR, EPDM)
- EPM (EPR) is a copolymer of ethylene and propylene. EPDM is a terpolymer of ethylene, propylene, and a diene third monomer used for cross-linking.
- Fluorocarbon (FKM)
- Fluorocarbon (FKM) has excellent resistance to high temperature and a broad range of chemicals. Permeability and compression set are excellent.
- Fluorosilicone (FVMQ)
- Fluorosilicone is a silicone polymer chain with fluorinated side-chains for improved oil and fuel resistance. The mechanical and physical properties are very similar to those of silicone.
- Hydrogenated Nitrile (HNBR)
- Hydrogenated nitrile was developed as an air-resistant variant of nitrile rubber. In HNBR, the carbon-carbon double bonds in the main polymer chain are saturated with hydrogen atoms in a process called “hydrogenation” that improves the material’s thermal stability and oxidation resistance.
- Polyacrylate (ACM)
- ACM (acrylic rubber) has good resistance to mineral oil, oxygen and ozone. The water compatibility and cold flexibility of ACM are considerably worse than with Acrylonitrile-Butadiene.
- Silicone (VMQ)
- Silicones possess good insulating properties and tends to be physiologically neutral. However, silicone elastomers have relatively low tensile strength, poor tear and wear resistance.
CUSTOM PARKER O-RINGSWhatever your o-ring needs, Wyatt is here to assist. Browse our extensive inventory of o-rings, and feel free to reach out to our support unit for developing o-ring prototypes or questions regarding fulfillment and support for your manufacturing needs