Teflon® and PTFE Back-Up Rings

Advanced Industrial is a leading manufacturer of high-performance, custom-machined PTFE and Teflon® back-up rings. We specialize in producing rings for demanding applications where standard seals fail. Our expertise in working with a wide range of PTFE materials ensures that you receive a durable, reliable product that meets your exact specifications.

What Are Back-Up Rings?

Back-up rings, also known as anti-extrusion rings, are essential components in high-pressure sealing applications. They are designed to be used with O-rings (or other elastomeric seals) to prevent the O-ring from extruding into the clearance gap between mating parts. When a system’s pressure exceeds the O-ring’s ability to resist the extrusion force, the O-ring can be damaged, leading to seal failure.

A back-up ring is installed on the low-pressure side of the seal. For applications with pressure from both directions, two back-up rings are used (one on each side of the O-ring). By providing a rigid, low-friction support structure, back-up rings significantly increase the pressure rating and lifespan of the entire sealing system.

Why Use PTFE for Back-Up Rings?

While back-up rings can be made from various materials, PTFE (and its brand name equivalent, Teflon®) is an ideal choice for many applications due to its unique properties:

• Extremely Low Friction: PTFE has one of the lowest coefficients of friction of any solid material, making it perfect for dynamic applications where it reduces wear and tear on moving parts.
• Chemical Inertness: PTFE is resistant to almost all industrial chemicals and solvents, ensuring seal integrity in harsh environments.
• High-Temperature Resistance: PTFE can operate in high-temperature environments without degrading.
• Flexibility: It is flexible enough to be installed easily without damage.

Everyday Applications of PTFE Back-Up Rings

Our custom PTFE back-up rings are used in a wide range of industries and applications.  Here are some of the more common use cases for Teflon back up rings:

Hydraulic Cylinders

In both static and dynamic hydraulic systems, PTFE back-up rings are essential for supporting O-rings under high pressure. They prevent the primary seal from being forced into the clearance gap during rod or piston movement, drastically extending the life of the cylinder and preventing fluid leaks. The exceptional dimensional stability of Teflon ensures that back-up rings maintain their shape and sealing effectiveness even under extreme pressure cycling, where hydraulic systems can experience pressures exceeding 5,000 PSI. These back-up rings are particularly critical in mobile hydraulic equipment like excavators, cranes, and agricultural machinery, where cylinder failure can result in costly downtime and safety hazards.

Valves

PTFE back-up rings are commonly used to seal valve stems and bodies in ball, gate, and butterfly valves. They provide reliable sealing in applications involving aggressive chemicals or high temperatures where elastomeric seals alone would degrade and fail. The chemical inertness of Teflon makes these back-up rings ideal for process valves handling corrosive media, while their low friction properties reduce the torque required to operate valve stems, extending actuator life and improving system efficiency. These sealing systems are essential in applications ranging from water treatment plants to chemical processing facilities, where valve reliability directly impacts operational safety and environmental compliance.  We also make Telfon valve seats.

Pumps

For both reciprocating and rotary pumps, back-up rings provide critical support for seals that are exposed to high discharge pressures. The low-friction nature of PTFE is especially beneficial in dynamic pump applications, reducing wear on moving parts and improving overall efficiency. Teflon back-up rings are particularly valuable in high-pressure injection pumps, chemical metering pumps, and industrial process pumps where seal failure can contaminate products or create hazardous conditions. The material’s resistance to abrasive particles and its ability to maintain sealing performance across temperature variations make these back-up rings essential for maintaining pump reliability in continuous operation environments.

Actuators

Pneumatic and hydraulic actuators rely on consistent pressure to generate precise force and movement. PTFE back-up rings ensure the integrity of piston and rod seals, preventing pressure loss and ensuring the actuator performs reliably and accurately over its service life. These back-up rings are critical in automated manufacturing equipment, where precise positioning and consistent force application are essential for product quality and production efficiency. Teflon’s low creep characteristics ensure that back-up rings maintain their dimensional integrity over millions of operating cycles, making them ideal for high-frequency actuator applications in packaging machinery, robotics, and assembly line equipment.

High-Pressure Pneumatic Systems

While pneumatic systems typically operate at lower pressures than hydraulics, high-pressure air applications can still cause standard O-rings to extrude. PTFE back-up rings provide the necessary rigidity to support seals in these systems, ensuring safe and efficient operation. These applications include compressed air storage systems, pneumatic tools, and industrial air compressors where operating pressures can reach several hundred PSI. The superior gas barrier properties of Teflon help minimize air leakage, improving system efficiency and reducing energy costs associated with compressed air generation and distribution.

Aerospace and Automotive Systems

In critical applications like aircraft landing gear, braking systems, and automotive transmissions, seal failure is not an option. PTFE back-up rings are specified for their reliability across a wide range of temperatures and their resistance to aggressive hydraulic fluids, fuels, and lubricants. These systems must function reliably in extreme environments, from the sub-zero temperatures of high altitude flight to the intense heat generated by braking systems and engine compartments. Teflon back-up rings provide the mechanical strength and chemical compatibility needed to ensure these safety-critical systems perform flawlessly throughout their service life, meeting the stringent reliability requirements of aerospace and automotive manufacturers.

PTFE Materials for Back-Up Rings

We machine back-up rings from a variety of PTFE materials. The best material for your application will depend on factors like operating pressure, temperature, and the media being sealed.

Custom Machined PTFE Back-Up Rings to Your Specifications

At Advanced Industrial, we don’t just sell standard parts. We work with you to understand your application’s unique challenges and machine custom PTFE back-up rings to your exact specifications. We can also help you with PTFE thrust washers, Teflon gaskets and seals, Teflon O-rings and PTFE valve seats.

We can produce rings in a variety of profiles, including:

• Solid (uncut)
• Split (scarf-cut)
• Spiral

Our state-of-the-art precision CNC machining centers allow us to hold tight tolerances and deliver your parts on time. Contact us today to discuss your project and get a quote for custom PTFE back-up rings.

We also make the following products in Teflon / PTFE:

• Back Up Rings
• Teflon Gaskets and Seals
• PTFE Valve Seats
• Teflon / PTFE O-Rings
• Teflon / PTFE Thrust Washers