力学分析在压力容器失效中的作用

The Role of Stress Calculation in the Failure Analysis of Pressure Vessel

以聚合釜为例,对压力容器的边缘应力的概念及其在失效分析中的作用进行了分析。聚合釜下温度计套管处经常开裂,失效分析表明为腐蚀疲劳开裂。有限元计算表明,下温度计套管离下封头过近导致该处因边缘应力过大而出现应力集中,在交变载荷作用下发生疲劳。

Taking polymerization kettle as an example, the concept of edge stress was introduced into failure analysis of pressure vessels., The cracks would occur near welding zone of low thermometer socket pipe in the kettle, and were induced by the corrosion fatigue. The finite element method was used to analyze the stress near the crack. The results showed that a too short distance from the low thermometer socket pipe to low closure in the kettle would cause stress concentration due to the excessive edge stress at this zone, and, as a result, the fatigue cracks would occur by the action of alternating load.