Approximate stress-intensity factor solutions for nozzle corner cracks

In this paper first the iso-stress lines at a nozzle corner are simplified into slanted straight lines at an angle of 45° with the walls of cylinder and nozzle and the natural nozzle corner cracks as quarter-circular ones. On the basis of this, a stress-intensity factor solution for an arbitrary poi...

Full description

Saved in:
Bibliographic Details
Published in:The International journal of pressure vessels and piping 1990, Vol.42 (1), p.75-96
Main Authors: Chai Guozhong, Hong Qichao
Format: Article
Language:English
Subjects:
Applied sciences
Exact sciences and technology
Mechanical engineering. Machine design
Steel design
Steel tanks and pressure vessels
boiler manufacturing
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In this paper first the iso-stress lines at a nozzle corner are simplified into slanted straight lines at an angle of 45° with the walls of cylinder and nozzle and the natural nozzle corner cracks as quarter-circular ones. On the basis of this, a stress-intensity factor solution for an arbitrary point on the crack front is derived by means of approximate analysis. Following from this, approximate expressions of the maximum and average stress-intensity factors K i max and K im are proposed, which are very important to the analysis of fatigue and fracture of practical pressure vessel nozzle corner cracks. These expressions show good consistency with the results of FEM, Kobayashi's approximate analysis and Besuner's IFM for about 40 cracks from nine nozzle sections. The expressions of K i max and K im are not only very simple but also have excellent accuracy; for most cracks the error is less than 10%.
ISSN:0308-0161
1879-3541
DOI:10.1016/0308-0161(90)90056-N