压力容器原始制造缺陷危害性分析

Perniciousness Analysis of Original Manufacturing Defects in Pressure Vessel

针对压力容器制造过程中存在的气孔、夹渣等原始制造缺陷,基于损伤力学理论建立了含缺陷的压力容器环向应力和经向应力数学模型,利用ABAQUS有限元分析软件对原始制造缺陷的应力集中进行了计算,验证了理论推导结果。结果表明,压力容器制造过程中的气孔、夹渣等原始制造缺陷,使得缺陷区域材料承载面积减少,内部应力增加,在工作载荷的长期作用下会进一步发展,甚至引发材料失效行为。最后提出在压力容器设计、制造、定期检验环节应当考虑原始制造缺陷的危害性,并采取有效措施,防止压力容器事故发生。

For the original manufacture defects such as pores, slag inclusions and other defects in pressure vessel manufacturing process, hoop stress and axial stress mathematical model of pressure vessels with defects were established based on damage mechanics. The stress concentration was calculated by ABAQUS and its perniciousness near original manufacturing defect was analyzed. The results show that the pores, slag inclusions and other defects in pressure vessel manufacturing process make the bearing area of material with defects decrease and internal stress increase under work load in the long-term effects, which will make defects deteriorated and even cause material failure behavior. Furthermore, it concludes that the perniciousness of original manufacturing defects should be considered in the process of pressure vessel design, manufacture and periodic inspection, and effective measures should be taken to prevent pressure vessel accidents.