• CN：11-2187/TH
• ISSN：0577-6686

›› 2006, Vol. 42 ›› Issue (9): 214-218.

• 论文 •

### 压力容器焊缝咬边疲劳裂纹的启裂寿命

1. 江苏工业学院油气储运技术省重点实验室
• 发布日期:2006-09-15

### INITIATION LIFE OF WELD UNDERCUTS FATIGUE CRACK IN PRESSURE VESSEL

WEI An’an;YOU Yikuang;LU Yi;GAO Guangfan;WANG Lei

1. Jiangsu key Laberatory of Oil and Gas Storage and Transportation, Jiangsu Polytechnic University
• Published:2006-09-15

Abstract: Aiming at the pressure condition of the weld undercuts of the air spherical tank under the fluctuant pressure in an enterprise, the mechanics model of the structure with undercuts is built, the graphology and finite element method are respectively used to calculate the elasticity stress concentration factor, then the nominal stress about the undercut tip is calculated. Then the initiation life of fatigue crack is estimated according to the experimental estimate expression. Using the samples with equal thickness to the tank and with the same size as the real undercuts, a simulation fatigue testes are performed under the stress range of an actual structure. As a result, the estimating life according to the experimental estimate expression approaches to the experimental life. Sequentially, theoretical basis and the experimental data for study on fatigue crack initiation life of the undercut is provided. Considering some safety factor, the remain life of the tank is 9 years, the remain initiation life of fatigue crack is 6 years.

Key words: Fatigue crack, Initiation life, Undercut