BALANCING THE FIRST-ORDER EXTERNAL MOMENTS OF MAN-B & W FOUR-CYLINDER LOW-SPEED ENGINES

The inertia forces from unbalanced rotating and reciprocating masses, and the unbalanced external moments created by these forces, are discussed with particular reference to MAN-B & W four-cylinder low-speed engines. It is mentioned that a number of ships are already in service with 4L90, 4L80, 4L67 and 4L45 engines of the GFCA series, and none has had problems with hull vibration excited by first-order external moments. The Author <of B & W Diesel> discusses in some detail these first-order extemal moments, and explains methods of controlling them so that excessive hull vibration from this source is avoided. An additional adjustable balancing system, developed by B & W for four-cylinder two-stroke engines and consisting of a pair of adjustable counterweights attached to the main counterweight and a similar pair attached to the turning-wheel, is described; its principle is the transfer of moments from the horizontal plane to the vertical, or vice versa. A first-order moment compensator for exceptional conditions, which eliminates the possibility of excitation of first-order vibrations in both the horizontal and vertical planes, is also described.

  • Supplemental Notes:
    • Motor Ship, 64 <1983>, p.47 <June> (6 pp., 2 graphs, 8 diag., 2 phot)
  • Authors:
    • Lindquist, H
  • Publication Date: 1983

Language

  • English

Subject/Index Terms

  • Subject Areas: Marine Transportation;

Filing Info

  • Accession Number: 00685073
  • Record Type: Publication
  • Source Agency: British Maritime Technology
  • Files: TRIS
  • Created Date: Aug 14 1995 12:00AM