ESTIMATING CRITICAL SPEEDS OF STEPPED SHAFTS WITH FLEXIBLE BEARINGS

This paper presents a semi-graphical approach for finding the first critical speed of a stepped shaft with finite bearing stiffness. The method is particularly applicable to high-speed turbine rotors with journal bearings. Using Rayleigh's Method and the exact solution for whirling of a uniform shaft with variable support stiffness, estimates of the lowest critical speed are easily obtained which are useful in the design stage. First critical speeds determined by this method show good agreement with values computed by the Prohl Method for the normal range of bearing stiffness. A criterion is also established for determining if the criticals are bearing critical speeds or bending critical speeds, which is of importance in design.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/1623789
• Authors:
  • Salzman, R H
• Publication Date: 1971-7

Media Info

• Features: Figures; References;
• Pagination: p. 327-333
• Serial:
  • Marine Technology Society Journal
  • Volume: 8
  • Issue Number: 3
  • Publisher: Marine Technology Society
  • ISSN: 0025-3324
  • Serial URL: http://ingentaconnect.com/content/mts/mtsj

Subject/Index Terms

• TRT Terms: Bridge bearings; Critical velocity; Journal bearings; Shafts (Machinery); Vibration
• Old TRIS Terms: Bearing foundation stiffness; Critical shaft speed; Shaft vibration
• Subject Areas: Marine Transportation; Vehicles and Equipment;

Filing Info

• Accession Number: 00019190
• Record Type: Publication
• Source Agency: Society of Naval Architects and Marine Engineers
• Files: TRIS
• Created Date: Nov 8 1973 12:00AM