THERMIT WELDED RAILS, FULL FUSION PROCESS

The purpose of the test was to determine the strength and safety of Thermit welded rails (Full Fusion Process). Eight specimens of 131 lb. RE rail 8 ft. long, including a Thermit weld at the center, were provided for laboratory tests. For comparative purposes, eight similar specimens, including an Oxweld pressure weld, were furnished for test. All specimens were 131 lb. RE rail. Three specimens of each kind of weld were tested head down, and three specimens, head up, under the drop test machine. One specimen of each type of weld was tested head up and one head down, under static load, under the million pound testing machine. Results of the drop tests and static tests and of the hardness survey are shown on attached tabulated statements. Every Thermit welded rail broke with the first drop under the drop test machine, even though in one case with the rail tested head up the drop was reduced from 59" to 6" and the energy from 44,000 ft. pounds to 4500 ft. pounds. The Oxweld specimens each withstood the first and second blows with the full 44,000 ft. pounds energy. On the static test the Thermit rail tested head up broke at 262,000 pounds load on a 48" span, and the Thermit rail tested head down broke at 251,000 pounds load. The Oxweld specimen tested head down broke at 375,000 pounds with a square break directly through the weld. The Oxweld specimen tested head up did not break with a load of 375,000 pounds. The strength of the Thermit full fusion weld as determined by these tests does not approach the strength of a full section rail or that of a bolted joint. The grain structure is coarse, the fractures are brittle, indicating the probability that failures in service might be sudden and without warning.

  • Corporate Authors:

    Penn Central Transportation Company

    Transportation Center, 6 Penn Center Plaza
    Philadelphia, PA  USA  19104
  • Authors:
    • Code, C J
  • Publication Date: 1945-8-13

Media Info

  • Features: Tables;
  • Pagination: 9 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00040871
  • Record Type: Publication
  • Report/Paper Numbers: Test 407
  • Files: TRIS
  • Created Date: Jul 8 1994 12:00AM