Journal of Failure Analysis and Prevention

, Volume 7, Issue 6, pp 393–399 | Cite as

Corrosion Failure of a 30-Ton Tripod Jack

  • N. Ejaz
  • I. N. Qureshi
  • I. Salam
Case History


A failure investigation of the four most suspected members in the assembly of a 30 ton tripod jack was carried out. It was found that under the combined effect of corrosion and high stresses, crack(s) were generated in the weld region of the leg extension. The crack(s) propagated under the corrosion and repeated loading until it reached a threshold size and the tripod jack collapsed. The problem initiated due to corrosion. Failure of the other members of the tripod jack, that is, spacer, brace, and bolts were the result of subsequent damage after (during) failure of the leg extension.


AISI 4130 Weld failure Corrosion 


  1. 1.
    Properties and Selection; Iron and Steels, vol. 1, 9th edn. Metals Handbook, p. 125, 163, 129. American Society for Metals, Metals Park, OH (1978)Google Scholar
  2. 2.
    Stahlschlusel (Key to Steels), Alloys data base on CD ROM (1995)Google Scholar
  3. 3.
    Frick, J.P.: Woldman’s Engineering Alloys, 7th ed., p. 1425. ASM International, Materials Park, OH (1990)Google Scholar
  4. 4.
    Ross, R.D.: Metallic Materials; Specification Handbook, 204 (1992)Google Scholar
  5. 5.
    Metallography and Microstructure, vol. 9, 9th edn., Metals Handbook, pp. 231–236. American Society for Metals, Metals Park, OH (1985)Google Scholar
  6. 6.
    Fractography, vol. 12, 9th edn., Metal Handbook. p. 12. ASM International (1987)Google Scholar
  7. 7.
    Source Book In Failure Analysis, Metal Progress Engineering Bookshelf, pp. 346–348. American Society for Metals, Metals Park, OH (1974)Google Scholar
  8. 8.
    Systematic Analysis of Technical Failures, G.A Lange, Ed., pp. 242–254. FRG, Germany (1986)Google Scholar
  9. 9.
    Significance of the Weld Defects In Relation to the Fatigue Fracture, Newman, R.P, 128 (1989)Google Scholar

Copyright information

© ASM International 2007

Authors and Affiliations

  1. 1.Metallurgy DivisionKRLRawalpindiPakistan

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