水电站压力钢管的安全度设置水平

针对电力行业标准DL/T5141-2001《水电站压力钢管设计规范》修订中为水电站压力钢管设计选择适宜安全度设置水平的需要,广泛收集了国内外水电站压力钢管和压力容器方面的设计规范和相关文献资料,对国内外水电站压力钢管和压力容器设计规范的设计方法和安全度设置水平进行了分析与比较。结果表明,我国规范DL/T5141-2001的安全度设置水平是基本合适的,但明管相应于屈服强度及抗拉强度的安全系数明显偏高;埋管相应于抗拉强度的安全系数则偏低一些。针对明管、地下埋管和坝内埋管的受力特点以及破坏后果,提出了规范修订稿各种管型安全度设置水平的建议方案,供规范修订组选用和参考。

Safety level of hydropower steel penstocks

In order to set the appropriate safety level for hydropower stations penstocks in the revision of DL/T 5141-2001, several representative penstocks codes of hydropower stations and pressure vessel standards in China and foreign countries were selected, and their different design methods and corresponding safety levels were analyzed and compared. The results show that: (1) the safety level of code DL/T 5141-2001 is appropriate, but for exposed penstocks, the safety level are higher and could be reduced; (2) the safety level of underground penstock could be increased a little. Based on the mechanical characteristics of the exposed and underground penstocks and the serious results if they were damaged, four projects as reference were proposed for the revision of code.