Stern tube sealing became a more difficult problem in recent years, due to the larger sizes and the higher speeds of ships. KHI, therefore, have made a committee for establishing criteria of stern tube sealing systems. They investigated the working conditions of seals and its surroundings with an oil tanker and found that a large pressure fluctuation in the chamber between seal rings is caused by axial vibration as well as lateral vibration of the propeller shaft. Next they carried out various experiments in a laboratory with test equipment which is capable of testing a seal of 1,400 mm diameter, under condition similar to actual pressure, vibration, etc. Three causes of the pressure fluctuation are: the inertia force of oil flow in the chamber between the seal rings excited by the lateral vibration of the shaft, oil flow in the recess of the stern tube bearing excited by the axial vibration of the shaft, and the viscosity force of oil flow in the close clearance between the shaft and the seal elements. The pressure fluctuation causes the backward leakage due to instantaneous contrary pressure difference between the seal lips. The results of the studies contributed to establishment of the criteria for stern tube sealing systems.

  • Corporate Authors:

    Kawasaki Heavy Industries Limited, Technical Inst

    1-1, Kawasakicho
    Akaski-shi,   Japan 
  • Publication Date: 1973-7

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00084505
  • Record Type: Publication
  • Source Agency: Japan Shipbuilding Industry Foundation Library
  • Report/Paper Numbers: No. 50
  • Files: TRIS
  • Created Date: May 19 1975 12:00AM