O-Rings & Hydraulic Seals

FDA O-Rings

FDA products are used in industries where food or consumables are present, including food and beverage, dairy and pharmaceutical applications.

Chemours Kalrez®

Chemours™ Kalrez® perfluoroelastomer parts (FFKM) resist over 1,800 different chemicals, while offering the high temperature stability of PTFE (327°C).

They’re used in highly aggressive chemical processing, semiconductor wafer fabrication, pharmaceutical, oil and gas recovery, and aerospace applications. The long-term, proven performance of Kalrez® parts can mean less frequent seal changes, repairs and inspections, increasing process and equipment uptime for greater productivity and yield.

Greene Tweed Chemraz®

Chemraz® gives excellent sealing performance when exposed to mixes of aggressive chemicals found downhole and is often specified by operators. Special compounds have been formulated for improved resistance to rapid gas decompression and abrasion, giving significant reductions in downtime and maintenance.


The Perlast® range of perfluoroelastomer materials are at the leading edge of polymer technology. They have been developed to offer superior sealing solutions with enhanced performance and improved functionality, which is proven in the field.


This material is unique due to its resistance to petroleum products, steam, and phosphate-esters.


Noted for their very high resistance to heat and a wide variety of chemicals. Other key benefits include excellent resistance to aging and ozone, very low gas permeability and the fact that the materials are self-extinguishing. Standard FKM materials have excellent resistance to mineral oils and greases, aliphatic, aromatic and chlorinated hydrocarbons, fuels, non-flammable hydraulic fluids (HFD) and many organic solvents and chemicals.


Good resistance to hot water and steam, detergents, caustic potash solutions, sodium hydroxide solutions, silicone oils and greases, many polar solvents and many diluted acids and chemicals. Special formulations are excellent for use with glycol-based brake fluids. Unsuitable for use with mineral oil products: lubricants, oils, or fuels. Peroxide-cured compounds are suitable for higher temperatures.


Good resistance to petroleum, hydrocarbons, fuels. Widely used with most oils, hydraulic fluids, alcohol. Poor resistance to sunlight, weathering and ozone.

Basic temperature range, -40F to +250 F

Teflon Encapsulated O Rings

A Teflon® jacket gives the seal chemical inertness, whilst the Viton® or silicone core gives the seal resilience and energises the seal.

Teflon® and Viton® are both registered trademarks of Chemours Company

Quad rings

When squeezed upon installation, Quad Rings seal with 4 contact surfaces—2 small contact surfaces on the top and bottom. This contrasts with the standard O-ring’s comparatively larger single contact surfaces top and bottom. Quad Rings are most commonly used in reciprocating applications, where they provide reduced running and breakout friction and reduced risk of twisting or rolling when compared to O-rings.


The physical sealing performance of square rings in static applications is superior to that of O-rings, however in dynamic applications it is inferior to that of O-rings. Square rings are usually only used in dynamic applications as energizers in cap seal assemblies.

AVT SSI Offer a wide variety of O-Ring styles and materials, including:

  • American (standard) O-Rings
  • Metric
  • Square Cross-Section
  • Quad rings
  • Spool stock
  • Teflon® Encapsulated silicone core
  • Teflon® Encapsulated Viton core
  • Metallic
  • Gas energized
  • Spring energized
  • Buna-N
  • Viton®/FKM
  • Aflas® Asahi Glass
  • Perlast® Precision Polymer Engineering
  • Greene Tweed Chemraz
  • DuPont Kalrez
  • White FDA Buna
  • White FDA EPR
  • White FDA Viton
  • White FDA Perfluoroelastomer

Viton® and Teflon® are both registered trademarks of Chemours Company