0

Full Content is available to subscribers

Subscribe/Learn More  >

Stress Indices Evaluation of Piping Ratchet Fatigue From Extreme Dynamic Loading

[+] Author Affiliations
Zakaria N. Ibrahim

Consultant, Chicago-Ridge, IL

Paper No. PVP2006-ICPVT-11-93010, pp. 789-798; 10 pages
doi:10.1115/PVP2006-ICPVT-11-93010
From:
  • ASME 2006 Pressure Vessels and Piping/ICPVT-11 Conference
  • Volume 3: Design and Analysis
  • Vancouver, BC, Canada, July 23–27, 2006
  • Conference Sponsors: Pressure Vessels and Piping Division
  • ISBN: 0-7918-4754-3 | eISBN: 0-7918-3782-3
  • Copyright © 2006 by ASME

abstract

Piping systems are subjected to a wide range of anticipated and/or postulated dynamic loading. With the exception of steam propelled water slug flow transient, thee dynamic loading result in response reversals that have not the characteristics of sustained loading. Dynamic test to failure did not exhibit the classical collapse catastrophic failure mode. The dynamic response reversals exhibited gradual ratcheting and fatigue crack growth that concurrently lead to the failure. The stress intensity classifications provided by the piping stress indices, in conjunction with Edmunds and Beer or Bree Plate ratchet models, are utilized to estimate the accumulated ratchet strains in the pipe component. The allowed maximum accumulating local ratchet strain is set arbitrarily to 10%, which is less than half of the measured ratchet strains found in the dynamic tests. Simple criteria for evaluating the degradation level in the piping components subjected to the concurrent ratchet-fatigue failure mechanisms are presented. The approach utilizes a methodology similar to that used in the creep-fatigue interaction damage provided in the ASME Section III, Subsection NH, Appendix-T. Replacing the creep strain term by that of the ratchet strain, and replacing the bilinear damage function with the square root function, yields the ratchet-fatigue degradation criteria formulations presented in this paper. Considerations for the plastic buckling due to the accumulated compressive ratchet strains as well as the primary component of the piping thermal expansion stress due to elastic follow-up are also presented.

Copyright © 2006 by ASME

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In