汽轮机高压旁路取压管振动交变应力分析  

Study on vibration alternating stress of pressure tapping pipe of high-pressure by-pass pipeline of the steam turbine

作　　者：张伟勇 周帅 陈海鑫[1] 贺轼 刘昊远 徐德城[2] 刘寅立 ZHANG Weiyong;ZHOU Shuai;CHEN Haixin;HE Shi;LIU Haoyuan;XU Decheng;LIU Yinli(Zhejiang Zheneng Zhenhai Power Generation Co.,Ltd.,Ningbo,Zhejiang 315100,China;Suzhou Nuclear Power Research Institute Co.,Ltd.,Suzhou,Jiangsu 215004,China)

机构地区：[1]浙江浙能镇海发电有限责任公司,浙江宁波315100 [2]苏州热工研究院有限公司,江苏苏州215004

出　　处：《浙江电力》2023年第1期97-102,共6页Zhejiang Electric Power

基　　金：国家自然科学基金委员会-中国核工业集团有限公司核技术创新联合基金(U1867202)。

摘　　要：某火电机组高压旁路(以下简称“高旁”)系统投入使用时,因振动过大导致附属取压管断裂。进行减振改造后,需分析取压管的振动交变应力水平,评估其安全性。为此,通过应变测试法测量了高旁阀前后压差和开度变化情况下取压管曾开裂位置的振动交变应力水平,分析了取压管振动交变应力幅与高旁阀前后压差及其开度之间的关系,并给出取压管线可能发生疲劳断裂的临界操作参数,即当高旁阀开度为35%,高旁阀前后压差超过3.70 MPa时,取压管可能发生疲劳断裂。最后,通过分析得出结论:高旁管路振动以高频振动为主,其原因为高频声能激发并放大管道的高频壳壁振动。During the operation of a thermal power unit’s high-pressure bypass(HPB)system,excessive vibration caused the breakage of the attached pressure-tapping tube.After the vibration reduction modification,it is required to analyze the vibration alternating stress level of the pressure-tapping tube and assess its safety.To this end,the vibration alternating stress level at the cracked location of the pressure-tapping tube is measured by the strain test method under the change of differential pressure and opening degree before and after the high-pressure bypass valve.The relationship between the vibration alternating stress magnitude of the pressure-tapping tube and the differential pressure before and after the high-pressure bypass valve and its opening degree is analyzed.The critical operating parameters for the potential fatigue fracture of the pressure-tapping pipelines are given:when the opening degree of the high-pressure bypass valve is 35%,and its differential pressure exceeds 3.70 MPa,the fatigue fracture of the pressure-tapping tube may occur.Finally,it is concluded through analysis that the high-pressure bypass vibration mainly comprises high-frequency vibration due to the high-frequency acoustic energy,which excites and amplifies the high-frequency vibration on the pipeline wall.

关 键 词：高旁管路 取压管 振动 交变应力 

分 类 号：TM621[电气工程—电力系统及自动化]