FATIGUE LIFE COMPARISONS - OUTER COIL TRUCK SPRINGS (D-5 AND D-7 ALLOY STEEL VERSUS D-5 CARBON STEEL

Fatigue tests were conducted on three types of outer coil freight car truck springs. These tests were of constant amplitude cycle type with adjustments for spring set made every 24 hours to maintain an approximately constant stress range. As spring types tested possessed differing spring rates (constants), tests were conducted on an equal energy basis simulating a reasonable service loading. Specimens were cycled to failure or two-million cycles. Resulting data are used to compare fatigue rates of D-5 and D-7 alloy steel outer coils with that of D-5 carbon steel outer coils. Comparisons indicate that outer coil freight car truck springs made of alloy steel possess significantly lower fatigue failure rates than those made of carbon steel. Alloy steel springs also demonstrated a tendency to take less set than did carbon steel springs. As tested, alloy steel outer coils of the D-5 type proved more reliable than the D-7 outer coils.

Media Info

  • Features: Figures; Tables;
  • Pagination: 25 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00139454
  • Record Type: Publication
  • Source Agency: Association of American Railroads
  • Report/Paper Numbers: No. R-229
  • Files: TRIS
  • Created Date: Oct 6 1976 12:00AM