高水头电站压力钢管力学性能的试验研究

Experimental study for penstock's mechanical properties

钢板冷卷时产生的塑性变形和应变时效作用会损害钢材的缺口韧性,从而降低压力钢管的抗脆性断裂能力,因而在有关标准中对钢板允许冷卷的最小径厚比加以严格限制。然而随着现代冶金技术的进步、断裂力学理论的发展以及无损检测技术及控制技术的进步,如采用现有的一些规定将难以发挥优质材料的潜力。在此对某高水头电站径厚比超标的支管进行力学性能研究,通过对支管瓦片的应变时效敏感性、瓦片以及瓦片焊接接头的力学性能进行较全面的试验研究,来评定支管的安全性。结果表明,支管的各项力学性能指标均满足技术规范要求,可以安全使用。

Plastic deformation and strain aging effects generated when the steel plates are cold-rolled will undermine the notch toughness of steel and reduce the capacity of the resistance to brittle fracture of penstock.So,in interrelated standards,the most smallest diameter-thickness ratio of cold-rolled plates is restricted.However,with the development of modern metallurgy,fracture mechanics,nondestructive testing technology and control technology,the potential of high-quality materials is not made full use of and the project cost could not be reduced if the existing standards are still used.This paper studys the mechanical properties of the branch of the high head hydropower station in case that the diameter-thickness ratio of the branch doesn＇t meet specifications.By studying the strain aging sensitivity of the tiles of the branch of the high head hydropower station and the mechanical properties of tiles and its weld joints,the safety of the branch is tested.The study indicates that the mechanical Properties of the branch meet specifications and the branch could be safely used.