All seals will leak to some extent, even if it is minimal and referred to as "emission" rather than a leak. Such (elastomeric radial lip) dynamic oil seals cannot achieve absolute tightness. Only technical tightness can be achieved. Technical tightness is a loose term. A perfect sealing system does not exist. Leakage control must be defined by the user/application for each oil seal. Achieving higher leakage control might mean compromising on the degree of wear. The requirements for elastomeric radial lip oil seals, their mating surfaces (shafts) and lubricant are very specifically defined and are critical in achieving a successful seal.
This is a presentation from the International Aircraft Cabin Air Conference 2021 (Online, 15-18 March 2021)
