Stress intensity factor solutions for cracks in threaded fasteners Page: 4 of 35
This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided to UNT Digital Library by the UNT Libraries Government Documents Department.
Extracted Text
The following text was automatically extracted from the image on this page using optical character recognition software:
2
ABSTRACT: Nondimensional stress intensity factor (K) solutions for continuous
circumferential cracks in threaded fasteners were calculated using finite element methods that
determined the energy release rate during virtual crack extension. Assumed loading
conditions included both remote tension and nut loading, whereby the effects of applying the
load to the thread flank were considered. In addition, K solutions were developed for
axisymmetric surface cracks in notched and smooth round bars. Results showed that the stress
concentration of a thread causes a considerable increase in K for shallow cracks, but has
much less effect for longer cracks. In the latter case, values of K can be accurately estimated
from K solutions for axisymmetric cracks in smooth round bars. Nut loading increased K by
about 50% for shallow cracks, but this effect became negligible at crack depth-to-minor
diameter ratios (a/d) greater than 0.2. An evaluation of thread root acuity effects showed that
root radius has no effect on K when the crack depth exceeds 2% of the minor diameter.
Closed-form K solutions were developed for both remote-loading and nut-loading conditions
and for a wide range of thread root radii. The K solutions obtained in this study were
compared with available literature solutions for threaded fasteners as well as notched and
smooth round bars.
KEYWORDS: threaded fasteners, stress intensity factor solutions, axisymmetric cracks,
axisymmetric finite element analysis
Upcoming Pages
Here’s what’s next.
Search Inside
This article can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Article.
Oster, D. M. & Mills, W. J. Stress intensity factor solutions for cracks in threaded fasteners, article, February 1, 1999; West Mifflin, Pennsylvania. (https://digital.library.unt.edu/ark:/67531/metadc706328/m1/4/: accessed March 28, 2024), University of North Texas Libraries, UNT Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.