Sliding ring seal for pressurised water reactor coolant pump - has rings tilting to close gap as temperature rises

摘要

A sliding ring seal consists of a stationary ring and revolving ring with radial sealing gap between them. To compensate the effects from temperature changes, one or both rings have incorporated deformation elements in the face adjacent to the sealing gap and/or in the face remote from it; these deformation elements have a coefficient of thermal expansion which acts in the opposite sense to that of the material of the two sliding rings so that, as the temperature rises, the deformation element or elements cause one or both rings to tilt towards the other. Used in particular as a hydrostatic seal for the main circulating pump of a pressurised water reactor. Also for other hydrostatic sliding ring seals.