摘要
由腐蚀、冲蚀、机械损伤或清除表面缺陷引起的局部减薄是管道中常见的一种缺陷。局部减薄将导致管道的承载能力降低,并可能引起严重的事故。塑性极限载荷决定了结构的极限承载能力,是对含局部减薄管道进行安全评估的一个重要参数。然而,确定含局部减薄管道的极限载荷是一项非常复杂的工作,而且需要先进行管线应力分析。这篇论文应用数值分析方法,在大量算例的基础上,分析了在内压、弯矩联合载荷下含小面积、环向、轴向和大面积局部减薄管道的塑性极限载荷。最后,通过对管道设计准則和计算数据的对比分析,提出了一种含局部减薄压力管道的免于评定条件,在大多数情况下,这种方法不需要对管线进行应力分析,应用非常简便。
Localized wall - thinning caused by corrosion, erosion, mechanical damage or by grinding to eliminate surface defects is a common surficial defect in piping, it can reduce the load - carrying capability and even lead to severe accidents of the piping. The plastic limit load, which determines the load - carrying capacity of structures, is an important parameter in performing safety assessment of the localized wall - thinning piping. However, the determination of limit loads is by no means an easy task due to the complexity of loading conditions and the shape of localized wall - thinning. In this paper, numerical analysis method for plastic limit loads was adopted. Based on a large number of calculation examples, the effects of small area, axial, circumferential, and large area localized wall - thinning with different size on plastic limit loads and failure mode of pressure piping under the combined load of internal pressure and bending were studied. Finally, by comparing the piping design criteria and calculation data, a free - of- assessment method for plastic limit loads of pressure piping with localized wall - thinning is presented. In most cases, this method needs not the strength calculation for piping systems and can be used easily.
出处
《中国锅炉压力容器安全》
2003年第2期4-8,共5页
China Boiler and Pressure Vessel Safety
