FINAL REPORT ON THE EVALUATION OF CUSHIONED UNDERFRAMES

This report covers a study and evaluation of special cushioning devices under impact conditions. The types of devices tested included sliding center sill, end of car hydraulic draft gears and column connected draft gears. Each device was evaluated with both canned goods and steel lading which respectively represented a resilient type of lading and a heavy rigid type of lading. This study indicates that the commodity protection needs under impact are not entirely a function of the special cushioning device but are also related to loading methods and types of packaging. In these tests the indications of cushioning protection provided by different shock absorption systems as summarized from the conclusions made in this report are: 1. Sliding sill type cars with 18 to 30 in. travel gave the highest degree of protection of lading through reduction of body force and resultant acceleration, followed in descending order by end of car hydraulic draft gears, column connected draft gears and standard draft gears. 2. The non-continuous or "split" design of sliding center sill provided the maximum protection to the car structure under dynamic squeeze, followed in descending order by end of car hydraulic draft gears, conventional continuous or through designs of sliding center sills and column connected draft gears. 3. Length of travel of sliding center sill is not an absolute indication of overall performance, particularly under dynamic squeeze conditions. 4. Small differences in sliding sill travel do not significantly change the performance characteristics. 5. Floating loads shift excessively, even with sliding center sill cars. 6. Energy absorption means are needed at the couplers in sliding center sill cars. 7. Sliding sills require high column strength to prevent bending.

• Corporate Authors:

  Association of American Railroads Research Center

  3140 South Federal Street
  Chicago, IL  United States  60616
• Publication Date: 1965-8

Media Info

• Features: Figures; Tables;
• Pagination: 89 p.

Subject/Index Terms

• TRT Terms: Crash tests; Cushioning materials; Equipment tests; Freight cars; Gears; Train track dynamics
• Uncontrolled Terms: Draft gears
• Old TRIS Terms: Cushion underframe devices; Cushioning; Draft gear tests; Freight car component performance; Lading protection
• Subject Areas: Railroads; Research;

Filing Info

• Accession Number: 00083061
• Record Type: Publication
• Source Agency: Association of American Railroads Research Center
• Report/Paper Numbers: MR-443
• Files: TRIS
• Created Date: Apr 22 1976 12:00AM