LABYRINTH SEAL

• Main Authors: KANBE TAKEO, TAKESHITA TOYOO
• Format: Patent
• Language: English
• Published: 17.03.1983
• Subjects: BLASTING; CYLINDERS; ENGINE PLANTS IN GENERAL; ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; LIGHTING; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAMTURBINES; PISTONS; SEALINGS; STEAM ENGINES; THERMAL INSULATION IN GENERAL; WEAPONS

PURPOSE:To improve the sealing performance of a labyrinth seal, by designing restriction pieces for constituting a labyrinth seal to have different thicknesses corresponding to the fluid pressure acted thereto, and thereby eliminating damages of the restriction pieces and enabling to increase the number of the restriction pieces. CONSTITUTION:In a diaphragm packing 18, a plurality of ring-shaped restriction pieces 18b made of 15Cr-Mo steel are formed on the inner surface of a fixed support member 18a made of Mo steel through which a rotor shaft 14a is extended, in the manner that they project toward the outer surface of the rotor shaft 14a and are located side by side along the axis of the rotor shaft. These restriction pieces 18b are fitted into the support member 18a such that a small clearance delta is formed between the tops of the restriction pieces and the outer surface of the rotor shaft 14a. Here, arrangement is such that the thicknesses of the restriction pieces 18b are reduced gradually from the inlet side to the outlet side of steam according to the pressure acted to the restriction pieces. Therefore, it is enabled to increase the number of the restriction pieces as compared with that of the conventional arrangements and to prevent damages of the same since their thicknesses are selected to stand the pressure acted thereto.