在工程风险评价的失效可能性计算中，故障树重要度分析是一项重要技术。它经常遇到许多不确定，不完整的因素。采用粗糙集理论对这些不确定、不完整的数据进行处理与分析，并通过埋地燃气管道的外腐蚀故障树重要度分析的实例，阐述了粗糙集理论的概念、原理、方法和应用。结果表明，粗糙集理论是一种完全基于客观的综合重要度分析方法，在工程上具有实用意义。

Welded joint between different Cr-Mo steels are used in furnace tubes in petrochemical plants. A carbon migration from low Cr side to high Cr side in joint is often observed, which leads to the formation of decarburized zone and affects the performance and aervice time of the welded joint. Inthis paper the carbon migration between 9Cr1Mo and 15CrMo steels was studied. Accelerating experiments were performed. The relation between decarburized zone width and temperature and time of service was proposed to describe the influence of carbon migration on structural performance.

Four different topics for high-temperature components, namely the development of the assessment codes for the structural integrity of high-temperature components, the application of continuous damage mechanics and probabilistic damage mode on the life assessment of high-temperature components, the life extension for high-temperature components and a proposed strategy for remanufacturing of high-temperature components were discussed in this paper. These topics should provide some important insights for the design and re-design of high-temperature components.

In this paper the limit loads of a piping with local thinning areas (LTAs) are studied by orthogonal experiment design and elastic-plastic finite element analysis method, and the effect factors of the LTA on limit loads of piping are analyzed. A safety assessment procedure is proposed for piping with LTA under combined of internal pressure and bending moment.