摘要
火力发电机组在灵活运行时,锅炉会频繁启停和升降负荷,此过程中伴随着温度和载荷的交替变化,由此带来集箱管座频繁开裂问题。本文以过热器集箱为模板,建立含有集箱、管座角焊缝和管接头的有限元模型,并对机组在升负荷和降负荷过程中管座的温度场和应力场进行分析。结果表明:升降负荷过程中,集箱的温度平衡速度相对缓慢,管接头则快速平衡;升降负荷过程中,管座区域最大热应力发生在焊缝熔合线处,而机械应力主要受管内压力波动的影响。
Under flexible operation,the boilers of thermal power plants frequently start and stop,and load up and down,accompanied by alternating changes in temperature and load,resulting in frequent cracking of the header tube seat.This article uses the superheater header as a template to establish a finite element model containing the header,tube seat fillet welds,and tube joints.The temperature and stress fields of the tube seat during the process of load increase and decrease of the unit are analyzed.The results show that the temperature balance speed of the header is relatively slower during the load lifting process,while the tube joints balance more quickly.During the process of lifting and lowering the load,the maximum thermal stress in the tube seat area occurs at the weld bond line.The mechanical stress is mainly affected by the pressure fluctuations inside the tube.
作者
梁慧超
王硕
张鹏宇
郝维勋
LIANG Hui-chao;WANG Shuo;ZHANG Peng-yu;HAO Wei-xun(Heilongjiang Province River Basin Protection Center,Harbin 150046,China;Harbin Boiler Co.,Ltd.,Harbin 150046,China)
出处
《失效分析与预防》
2024年第3期166-171,共6页
Failure Analysis and Prevention
基金
黑龙江省自然科学基金(LH2022E079)。
关键词
集箱
管座开裂
有限元
热应力
机械应力
header
cracking of the tube seat
finite element
thermal stress
mechanical stress
