Non-vented rings (oi & oe) are designed for lower pressure ranges. The perfectly closed o ring design avoids ingress of the media into the seal. Moderate load, moderate pressure capability.
Metal o ring for internal & external pressure:
non-vented rings (oi & oe) are designed for lower pressure ranges. The perfectly closed o ring design avoids ingress of the media into the seal. Moderate load, moderate pressure capability.
Spring-energised metal o ring for internal pressure (osi) and (ose) for external pressure are designed for extreme low leakage at moderate pressures.
Internally (ovi) or externally (ove) vented o rings are designed for higher pressure. Besides the own seating load the seal is also energised by the system pressure.