PIPELINE SEAL (VERSIONS)

FIELD: heat power engineering. SUBSTANCE: invention relates to seals of pipelines of different systems and plants operating at temperature fluctuations, mainly, for pipelines passing steam or hot water over long distances. Proposed seal for pipeline includes inner and outer pipes and sealing rings. Said sealing rings are fitted on one pipe with radial clearance relative to opposite pipe with fixing of extreme ring from side of inner space of one of pipes. Extreme rings are installed in ring slots of rings-holders and are pressed, for instance, by springs, to side of opposite extreme rings. Viscous antifriction liquid or metal melt is placed in axial clearances between rings and in radial clearances between rings and pipes. Other method of sealing is laid in description of invention. Invention makes it possible to decrease friction forces, prevent jamming of sealing members at thermal shifts of sections of pipeline, "biting" of sealing rings if harmful admixtures get into clearance, improved tightness of sealing at elevated pressures inside pipes, protect seals and pipeline from destruction at impulse hydraulic or seismic disturbances. EFFECT: improved quality of sealing. 3 cl, 3 dwg