Seals, seats and bearings made from engineering polymers are designed to withstand extreme environments where high pressures and temperature often need to be overcome. Materials used for these critical components need to be of the highest quality.

Materials

PTFE back-up rings

Back-up rings are static seals, commonly installed with O-rings to prevent gap extrusion in static radial sealing in applications above 5 MPA. When high pressures are exerted, the soft material of the O-ring can be forced into the clearance gap, causing the O-ring to extrude. The hard back-up ring material will keep the O-ring from flowing into the gap, which will prevent premature failure. The size of the permissible extrusion gap depends mainly on the seal material, temperature and operating pressure

Back-up rings are available in extrusion resistant material such as PTFE. They are designed to fit between the O-ring and the extrusion gap and prevent the extrusion of the O-ring. The back-up ring is installed at the zero pressure side when the O-ring is exposed to pressure from one side. When the pressure comes from both sides, a back-up ring is installed on both sides. There are several types available: type S, SC, P, PC and SP.

Key properties 

  • Easy to install
  • Resistant to high pressure
  • Wide temperature range

Applications

  • Hydraulic cylinders
  • High-pressure hydraulic systems
  • High-pressure valves

Material selector

PTFE back-up rings

Back-up rings are static seals, commonly installed with O-rings to prevent gap extrusion in static radial sealing in applications above 5 MPA. When high pressures are exerted, the soft material of the O-ring can be forced into the clearance gap, causing the O-ring to extrude. The hard back-up ring material will keep the O-ring from flowing into the gap, which will prevent premature failure. The size of the permissible extrusion gap depends mainly on the seal material, temperature and operating pressure

Back-up rings are available in extrusion resistant material such as PTFE. They are designed to fit between the O-ring and the extrusion gap and prevent the extrusion of the O-ring. The back-up ring is installed at the zero pressure side when the O-ring is exposed to pressure from one side. When the pressure comes from both sides, a back-up ring is installed on both sides. There are several types available: type S, SC, P, PC and SP.

Key properties 

  • Easy to install
  • Resistant to high pressure
  • Wide temperature range

Applications

  • Hydraulic cylinders
  • High-pressure hydraulic systems
  • High-pressure valves