A test project undertaken jointly last year by Seaboard Coast Line and Pullman-Standard to determine the causes of premature wear in the truck areas of 150 five-year-old SCL 70-ton box cars has flushed out "truck hunting" as a major source of wearing action within the truck. Hunting, described as the natural tendency of the truck wheels to oscillate laterally between the rails at specific operating speeds, appears to be more prevalent with empty, roller bearing-equipped cars. Condition of the wheel treads, the tests revealed, will determine, more than anything else, the speed at which the mysterious hunting action will begin. There are other factors, however, that will determine the critical speed at which hunting is intiated, the researchers discovered. Among them are (1) the type of journal bearing, roller or friction; (2) load on the truck; (3) type of side bearing; (4) truck rigidity or squareness; and (5) wetness of the rail. The joint SCL/P-S project was conducted in mid-1972 on a 20-mile stretch of SCL welded rail mainline between Waycross and Offerman, Ga. Aside from one of the 70-ton box cars that had been experiencing the premature wear problem, equipment used in the test included a locomotive, an office car and a special caboose that doubled as the instrument car. To better observe and photograph the box car's hunting action, flooring at the B end in the bolster area was removed and replaced with clear Lexan "windows."

  • Corporate Authors:

    Simmons-Boardman Publishing Corporation

    P.O. Box 350
    Bristol, CT  United States  06010
  • Publication Date: 1973-5

Media Info

  • Features: Photos; Tables;
  • Pagination: 4 p.
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00046064
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jul 16 1974 12:00AM