What is the PTFE Spring Energized Seal

It’s a spring-energized U-cup that uses a variety of jacket profiles, spring types and materials in rod and piston, face and rotary seal configurations. They are used when elastomeric seals fail to meet temperature range, chemical resistance or friction requirements.

Jacket profiles are made from PTFE and other high performance polymers. Spring types are available in corrosion-resistant alloys, including stainless steel, Elgiloy and Hastelloy.


Since jackets are machined and not injection molded, the seal configuration can be easily adjusted when needed to enhance seal performance. The seal is machined on CNC lathes to very close tolerances, using only premium grade materials. Each design is available in standard and special diameters and cross sections in inch-fractional, AS4716, and metric sizes. The full size range includes diameters from 1/32 to 150 inches, with radial cross-sections ranging from 1/32 to several inches across.

Spring energized seal lips and spring energizer are compressed when installed into the seal gland. The resilient spring responds with constant force, pushing out the sealing lips and creating a gas tight seal against the sealing surfaces. The seal expands as pressure is introduced – increasing the sealing force beyond that provided by the spring and the jacket material.