Compressor Piston Rod Packing Rings And Wiper Rings
Material Properties of PTFE
Chemical Resistance: PTFE is highly resistant to a wide range of chemicals, making it suitable for use in aggressive environments where other materials might degrade.
Temperature Tolerance: PTFE can withstand a broad range of temperatures, typically from -200°C to +260°C (-328°F to +500°F), making it suitable for both cryogenic and high-temperature applications.
Low Friction: PTFE has one of the lowest coefficients of friction of any solid, reducing wear on the mating surfaces and the seal itself.
Non-Reactivity: PTFE is non-reactive and does not corrode, which is crucial for maintaining the integrity of the seal in various applications.
The primary function of a PTFE backup ring is to prevent the extrusion of the O-ring or primary seal material. Under high pressure, the sealing material can be forced into the gap between the mating surfaces, leading to extrusion and eventual seal failure. PTFE backup rings support the O-ring, keeping it in place and preventing extrusion.
Enhancing Seal Durability:
By providing support to the primary seal, PTFE backup rings enhance the overall durability and longevity of the sealing system. They reduce the wear and tear on the O-ring, leading to fewer replacements and less downtime.
Maintaining Seal Integrity:
PTFE backup rings help maintain the integrity of the seal by providing additional structural support. This ensures that the sealing function remains effective even under varying pressure and temperature conditions.
Types of PTFE Backup Rings
Solid Backup Rings:
These are simple, solid rings placed on one or both sides of the O-ring to provide support and prevent extrusion.
Split Backup Rings:
Split or scarf-cut backup rings have a diagonal cut that allows them to be installed without dismantling the assembly. This design makes installation easier, especially in field repairs.
Spiral Backup Rings:
These rings have a spiral design that can be wound into place. They offer flexibility and ease of installation while providing excellent support to the O-ring.
PTFE backup rings are critical components in sealing systems, particularly in high-pressure and chemically aggressive environments. Their primary function is to prevent the extrusion of O-rings or other seals, enhancing the durability and reliability of the sealing system. Made from PTFE, these backup rings benefit from the material’s excellent chemical resistance, high temperature tolerance, and low friction properties. They find applications across various industries, including hydraulics, pneumatics, chemical processing, oil and gas, aerospace, and automotive sectors, ensuring reliable performance and extended service life of the sealing components.
