Denver AMCON Show

See how Eclipse solved a low-torque, deep-sea sealing challenge for AUVs with a custom spring-energized seal and EH042 thermoplastic elastomer.

Aside from ball valve seats or non-contact labyrinth seals, PTFE is rarely used without a secondary energizer. This is due to PTFE’s inelastic nature. Unlike urethanes or elastomers which possess an inherent springiness, PTFE is often considered an “unalive” material. Much like a lump of clay, it will not bounce back once deformed. Especially in dynamic applications, this is not a desirable quality. Fortunately, with the addition of a spring or elastomer energizer, all of PTFE’s excellent attributes can be fully exploited in terms of sealing. Much like the rest of the seal industry, Eclipse utilizes three metallic spring energizer types for the seals we manufacture. Canted Coil, Cantilever V-Spring, and Helical. While each spring type ultimately accomplishes the same task, energizing a PTFE or polymer seal jacket, we’ll see that each type has unique properties better suited to certain applications.  Figure 1 below shows generalized load versus deflection curves for the three spring types. As you can see, each one is quite a bit different, favoring distinct circumstances and applications. Though, we’ll also find out load curves are not only deciding factor when choosing a spring.

Explore the innovation behind Eclipse’s polymer superfinishing technique that enabled high-performance PTFE seals to meet extreme hydrogen leakage and durability requirements in cryogenic aerospace applications.