基于ASME-Ⅷ-2的弹塑性棘轮分析实例

An Analysis Example of Elastic-plastic Ratchet Analysis Based on ASMEⅧ-2

当压力容器受压元件承受恒定的内压和循环温度载荷时,棘轮失效是一种重要的失效模式。按照ASME-Ⅷ-2规范5.5.7节对一筒体与封头结构进行弹塑性分析,结合有限元展示了弹性核准则的应用,及其与其他两个准则之间的联系。同时通过改变封头的结构型式展示了棘轮失效的现象,并与弹性棘轮分析方法进行了对比。因规范中关于棘轮评定准则描述比较简洁抽象,缺乏详细的实施步骤,旨在为其在工程实践中的实施提供指导。

Ratchet failure is an important failure mode when the components of the pressure vessel is subjected to constant internal pressure and cyclic temperature load. In this paper, elastic-plastic analysis of a cylinder and head structure was carried out in accordance with section 5.5.7 of ASME-Ⅷ-2, and the application of elastic core criterion and its relationship with other two criteria were demonstrated by using finite element method. At the same time, the failure of ratchet was shown by changing the structure of the head, and compared with the elastic ratchet analysis method.Due to the concise and abstract description of ratchet evaluation criteria in the specification,there is no detailed implementation steps, this paper aimed to provide guidance for its implementation in engineering practice.