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Frequently Asked Questions

Q I have a chemical pump manifold cover that our field techs need to disassemble periodically. Do you have an option to a TFE O-Ring that would not have to be replaced each time?

A Actually, we have two possible solutions. One is to use a TFE encapsulated O-Ring, or to use a high fluorine content fluoroelastomer O-Ring.

An encapsulated O-Ring consists of an elastomer (silicone, Viton® or EPDM) core around which is a molded PTFE jacket. The core gives the O-Ring more memory than a standard TFE O-Ring, while the jacket gives you the equivalent chemical resistance. This product enables multiple cycles of disassembly.

A high fluorine content fluoroelastomer O-Ring displays chemical resistance superior to commercial grade Viton®, at a fraction of the price of a perfluoroelastomer.

Consult with one of our Sales Representatives for help in product selection and pricing.

Q I've heard about Genuine Viton®. What does that mean?

A Viton® is a registered trademark of DuPont Elastomers. To put it simply, all Vitons® are fluoroelastomers, but not all fluoroelastomers are Viton®. Genuine Viton® is a licensing program initiated by Dupont Dow to both educate the market about the design benefits of using Genuine Viton® materials and to ensure integrity of the Viton® supply chain from Dupont to parts manufacturers to distributors to the ultimate end-user.

Q I need to seal a rotating shaft, but my internal pressure is greater than 5 psi, which is the maximum recommended pressure for my current oil seal. What can you offer?

A There are several issues that play into your situation, including shaft size and speed, temperature and life cycle expectancies. We do have standard designs that will seal up to 125 psi as well as custom designs that can seal over 1000 psi. Please give us your design parameters and let us do an analysis.

Q I am installing a piston T-seal and I am having trouble keeping the back-up rings in place as the piston is pushed into the cylinder. Do you have an installation tool that will facilitate this?

A Yes, we have designs for a variety of assembly tools, but we have an even better solution for you. One of our manufacturers has a new design of T-seal (and Capped T-seal too!) where the back-up rings are designed to interlock (via mating lobes) with the elastomer element of the seal. Once the seal is assembled in its groove, the back up rings will not pop out, keeping your fingers clear of danger.

Q I'm dealing with potable water. Do you have any seals for this?

A Yes, we have several materials suitable for FDA/NSF applications. As the variety of options is too numerous to discuss here, please call one of our Sales Representatives.

Q I have an application where low hysteresis (The lag between making a change, such as increasing or decreasing power, and the response or effect of that change) is critical. What do you recommend?

A We have had several customer applications where low break away friction in the seal was a critical element. The best example is in a pressure transducer application where not only low hysteresis was needed, but more importantly CONSISTENT hysteresis over time (and over a 0 to 3,000 psi pressure range!) was required. We designed a spring energized PTFE lip seal with a highly customized lip design to solve this problem.