脉动载荷下换热器管板接头塑性失效研究  

Research on plastic failure at tube-tubesheet joint of heat exchangers under pulsating loads

作　　者：张建华[1] 朱国栋[2] 王娟[1] ZHANG Jianhua;ZHU Guodong;WANG Juan(China University of Petroleum-Beijing,Beijing 102249,China;China Special Equipment Inspection and Research Institute,Beijing 100029,China)

机构地区：[1]中国石油大学(北京),北京102249 [2]中国特种设备检测研究院,北京100029

出　　处：《压力容器》2023年第1期46-54,共9页Pressure Vessel Technology

基　　金：国家重点研究计划项目(2018YFC0808805);国家质检公益项目(201410248)。

摘　　要：管板接头是换热器常见失效部位,其中交替塑性失效模式缺乏研究。基于材料的多线性等向强化(MISO)本构模型,对U型管式换热器角焊缝管板接头和新型内孔焊管板接头进行了弹塑性数值模拟。通过提取管板管桥中心及管板管孔附近区域的节点的应力及应变数据,得到了在脉动递增载荷下的双向应力和应变规律。结果表明,在脉动载荷的递增加载与卸载过程中,两管板接头的残余应力与残余应变存在差异;随着脉动幅值的递增,塑性应变不断累积,为防止结构最终发生塑性失效,需对应变进行合理控制。通过分析发现管接头内缘处是较容易发生交替塑性失效的部位,在对换热器管板接头失效分析时,应重视载荷历程和焊接接头形式对管板的影响。The joints connecting the tubesheet and the tubes are the frequent failure positions.There is a lack of research on alternating plastic failure modes.Elastoplastic numerical analysis was carried out for tubesheet joint of U-type tube heat exchanger,and the new type inside hole welded tubesheet joint,based on Multilinear Isotropic Hardening(MISO)constitutive model.By extracting the stress and strain data of the nodes at the center of tube bridge of the tubesheet and near the tube hole of the tubesheet,the biaxial stress and strain laws under the pulsating pressure load were obtained.The result show that during the incremental loading and unloading process of pulsating pressure load,the residual stress and strain of the two tubesheet joints are different.With the increase of pressure,the plastic strain of the tubesheet accumulates continuously.The strain should be controlled reasonably in order to prevent the plastic failure of the structure.Through the analysis,it is found that the area near the inner edge of the tubesheet joint is the place where alternating plastic failure is more likely to occur.For the plastic failure analysis of heat exchanger tubesheet joints,more attention should be paid to the influence of load history and welded joint form on tubesheets.

关 键 词：换热器 管板 失效分析 残余应变 塑性累积 

分 类 号：TH49[机械工程—机械制造及自动化] TQ051.5[化学工程] O344.1[理学—固体力学]