Spring Energized PTFE Seals
A spring energized PTFE seal has three basic elements:
• A pressure-actuated, U-shaped jacket
• A metal spring-loading device
• High performance polymeric seal materials
The seal is energized by a spring made from stainless steel. The spring supplies all of the load required for sealing when the media pressure is too low to fully actuate the lips.
The flexible spring allows for a wide tolerance range that can help overcome hardware misalignment and eccentricity, without causing excess friction or the inability to seal.
Spring energized PTFE seals perform reliably in a wide range of applications where conventional elastomeric seals fail due to chemical attack, extreme cold or heat, extrusion, friction or compression set.
The spring energized PTFE seal is a spring-energized U-cup utilizing a variety of jacket profiles, spring types and materials in Rod & Piston, Face and Rotary seal configurations. Spring energized PTFE seals are used where elastomeric seals fail to meet the 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 metal 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, creating a gas tight seal against the sealing surfaces. As pressure is introduced in the system the seal expands – increasing the sealing force beyond that provided by the spring and the jacket material.
Gallagher offers small run prototype batches to ensure the parts perform to customer expectations.
Download our new Spring Energized PTFE Seal Guide for more information.
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