Seals and Gaskets for Demanding Applications

A Proven Performer Spreads its Wings

DuPont™ Kalrez® perfluoroelastomer parts are engineered to stand up against jet fuel, engine lubrication oils, hydraulic fluids, rocket propellants and oxidizers, all in the presence of extreme temperatures. The exceptional performance of Kalrez® parts are proven in applications, including mechanical seals in the chemical process industry, aviation, marine and gas turbines, auxiliary power units, hydraulic actuators and bleed air valves and fittings. Kalrez® perfluoroelastomer parts are manufactured and are sold by DuPont and its authorized distributors.

Kalrez® AeroSeal™ 7777 and 7797, developed for outstanding thermal stability at 325°C (617°F) and excellent compression set resistance, have been selected for use in jet engines. Both have superior High Thermo-oxidative Stability (HTS).

The latest product Kalrez® 7800 resists corrosion with titanium, and is manufactured in accordance with AMS7257D.

Matching Resistance to Chemical Processes

DuPont™ Viton® fluoroelastomers are the standard for broad chemical resistance for applications up to 230°C, The Viton® family consists of many polymer grades with varying levels of fluorine content and cure chemistries, permitting a balance of chemical resistance and mechanical properties to be selected to match the application.

DuPont™ Viton® is the elastomer of choice in mechanical seals and associated applications in the chemical process industry, due to its great chemical resistance, high temperature capabilities, polymer traceability and associated technical services provided by DuPont.

Driving Seals to New Standards

As fuel emission regulations continue to escalate industry challenges, DuPont™ Viton® fluoroelastomers have been selected for their effectiveness in underhood applications, helping carmakers meet their near-zero fuel permeation targets.

Viton® performs well in gasoline-alcohol blends, which are generally more aggressive than standard gasoline types. Viton® also provides excellent performance in biodiesel fuels. This helps design engineers make informed material choices for fuel system seals, O-rings and gaskets, which are critical parameters needed for meeting stringent emission regulations.

Bonding with Cost-Effective Performance

DuPont™ Vamac® ethylene acrylic elastomer provides resistance to mineral-based oils and synthetic engine oils at operating temperatures ranging from -40ºC (-40ºF) to 150º+ C (302ºF). Vamac® also provides excellent performance in the newest and most aggressive automatic transmission fluids (ATF).

Examples of Vamac® applications include:

  • Transmission lip seals – hot, cold, pressure, good process ability for seal dimensions and fit
  • Cam cover gaskets – low melt viscosity for molding and overmolding long sections; excellent swell resistance to keep thickness of gasket stable, eliminating leakage and oil weep.
  • Bonded Piston Seals — high-temperature durability and resistance to automotive service lubricants.

Versatile, Cost-Effective Solutions

Neoprene polychloroprene has been used sealing applications since the 1930s for its many advantages over natural rubber, including resistance to heat, weather, ozone, flame, oil, hydrocarbon fluids, and a broad range of other chemicals. It’s also exceptionally tough and resists cracking and abrasion, for applications such as belting and jacketing. Neoprene remains a tested, cost-effective choice for many sealing, mechanical and industrial applications, due to:

  • Outstanding physical toughness.
  • Excellent resistance to damage caused by flexing and twisting.
  • Resistance to degradation from sun, ozone, and weather.
  • Great performance in contact with oils and many chemicals.
  • Maintains physical properties over a wide temperature range

Highway and bridge seals have been manufactured with Neoprene for over 50 years. Window seals can be produced for maintenance-free applications in the most challenging designs and environments.