Journal of Failure Analysis and Prevention

, Volume 5, Issue 4, pp 54–61 | Cite as

Failure of ethylene furnace outlet transfer line due to overheating

  • A. Ul-Hamid
  • H. M. Tawancy
  • A. I. Mohammed
  • N. M. Abbas
  • S. S. Al-Jaroudi
Peer Reviewed Articles

Abstract

An outlet transfer line tube of an ethylene-cracking furnace failed after five years of service. The tube, made from Incoloy alloy 800H, developed cracks that penetrated the entire thickness. Optical and scanning electron microscopy, X-ray diffraction, and microhardness tests were used to evaluate the failed tube. It was found that the tube was considerably embrittled by high-temperature carburization, leading to intergranular fracture at the inner surface. Carburization appeared to have been caused by high-temperature exposure to the carbonrich atmosphere associated with the coke adhered to the inner surface. Additionally, the decrease in heat transfer due to the coke deposits caused the wall temperature to increase during service. However, at the outer surface, the tube fractured by a fatigue process that could result from the use of a counterweight to prevent sagging of the tube as a result of the coke deposition. Based on the results obtained, a short-term solution was to modify various process parameters to reduce the extent of coke deposition and/or increase the frequency of decoking and to discontinue the use of a counterweight. However, the long-term solution is to replace alloy 800H.

Keywords

carburization fatigue SEM transfer line 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    J. Blackburn: in “Carburization in High Temperature Process Plant Materials,” Repon EUR 7773, Colloquium Proceedings, coordinated by J. Nonon, Commission of the European Communities, Luxembourg, 1981, p. 7.Google Scholar
  2. 2.
    G.Y. Lai: in High Temperature Corrosion in Energy Systems, M.F. Rothman, ed., TMS-AIME, Warrendale, PA, 1985, p. 551.Google Scholar
  3. 3.
    G.M. Smith, D.J. Young, and D.L. Trimm: Oxid. Met., 1982, 18(5/6), p. 229.CrossRefGoogle Scholar
  4. 4.
    H.M. Tawancy and N.M. Abbas: J. Mater. Sci., 1992, 26, p. 1061.CrossRefGoogle Scholar
  5. 5.
    A. Schnaas and H.J. Grabk: Oxid. Met., 1978, 12(5), p. 387.CrossRefGoogle Scholar
  6. 6.
    M.F. Rothman, G.Y. Lai, M.M. Antony, and A.E. Miller: Technical File 11622, Haynes International Company, Kokomo, IN, January 31, 1984.Google Scholar
  7. 7.
    “Incoloy Alloys 800H and 800T Data Brochure,” Inco Alloys International, Newton, NC, 1986.Google Scholar
  8. 8.
    J. Norton: in “Carburization in High Temperature Process Plant Materials,” Repon EUR 7773, Colloquium Proceedings, coordinated by J. Nonon, Commission of the European Communities, Luxembourg, 1981, p. 43.Google Scholar

Copyright information

© ASM International 2005

Authors and Affiliations

  • A. Ul-Hamid
    • 1
  • H. M. Tawancy
    • 1
  • A. I. Mohammed
    • 1
  • N. M. Abbas
    • 1
  • S. S. Al-Jaroudi
    • 2
  1. 1.Center for Engineering Research, Research InstituteKing Fahd University of Petroleum & MineralsDhahranSaudi Arabia
  2. 2.Saudi AramcoTanajibSaudi Arabia

Personalised recommendations