BACK-UP RINGS

Back-up rings are used with static, as well dynamic applications. However, they have no sealing function.
Extrusion of O-rings or X-Rings under the influence of pressure should be avoided with the back-up ring.
Manufacture of back-up rings in various materials is possible.

Special Features:

• Simple groove geometry
• Easy assembly
• Multitude of materials of construction
• Individual sizes possible
• Bridging of large sealing gaps
• High areas of temperature
• Neutral to fluctuations in temperature

We recommend the use of back-up rings for one or more of the following conditions in service: pressure over 5 MPa (50 bar)

• Larger sealing splits
• Higher stroke frequency
• High temperature fluctuations
• Pulsating pressures
• STR (recommended assembly / mounting sizes for O-rings)
• Back-up rings of the STR series are produced from special polyurethane elastomer through a
  special process. The material - hardness 95 shore A - has excellent extrusion resistance.
  It is, however, possible to use endlessly manufactured back-up rings for external
  sealing applications due to their
  memory effect. These back-up rings are meant for automatic assembly. Special
  anti-ageing additives in the material are also effective in dry air and oil.
  
  

AF-100, 110, 120, 140 and AF-150

Rings of this series are produced by turning, and we recommend specific explanations according to specific applications ( see below) 

Material overview for back up rings:

• AF-1012 - Virgin PTFE 
• AF-1022 - PTFE with additive
• AF-2426 - PTFE with carbon
• AF-4125 - PTFE with glassfiber
• AF-5640 - PTFE with bronze/additive