压力容器2026，Vol.43Issue(3)：70-77,8.DOI:10.3969/j.issn.1001-4837.2026.03.007
1000MW超超临界机组高压旁路阀减温水喷嘴焊缝开裂失效机理与设计优化
Cracking failure mechanism and design optimization of the desuperheating water spray nozzle weld of a high-pressure bypass valve in a 1 000 MW ultra-supercritical unit
摘要
Abstract
To address the issue of frequent cracking in the weld of the desuperheating water spray nozzle of a high-pressure bypass valve in a 1 000 MW ultra-supercritical unit,the failure mechanism of the weld was revealed and a structural optimization scheme was proposed by means of metallographic structure analysis,microhardness testing,and other physical and chemical inspection methods combined with finite element numerical simulation technology.The results show that the high hardness of the weld between the desuperheating water inlet pipe and the nozzle,together with the low-cycle strain fatigue induced by structural constraints,mutually superimposed to promote the rapid initiation and propagation of cracks in the fillet weld,thereby leading to leakage of the desuperheating water pipe.For the optimization scheme of lengthening the vertical desuperheating water pipe to enhance pipeline flexibility,finite element analysis shows that when the vertical pipe length is increased to 380 mm,the stress at the fillet weld significantly decreases to 65 MPa,effectively avoiding stress concentration.The research results can provide reference for the structural design and safe operation of similar high-pressure bypass valves.关键词
超超临界机组/高压旁路阀门/失效分析/有限元分析/应力计算Key words
ultra-supercritical unit/high-pressure bypass valves/failure anasysis/finite element analysis/stress calculation分类
机械制造引用本文复制引用
殷兆广,闾川阳,董勤,徐以伟,赵炜炜,王云庆,顾渊,陈秉怡,崔益民,赵宁宁..1000MW超超临界机组高压旁路阀减温水喷嘴焊缝开裂失效机理与设计优化[J].压力容器,2026,43(3):70-77,8.基金项目
国家自然科学基金青年科学基金项目(52105162) （52105162）
浙能集团科技项目(ZNKJ-2024-027) （ZNKJ-2024-027）
