基于有限元分析的大型核电汽轮机轴系中心偏差的影响分析  

The Influence Analysis of Shaft Misalignment of Large Nuclear Power Turbine Based on Finite Element Method

作　　者：姜海涛 JIANG Hai-tao(Liaoning Hongyanhe Nuclear Power Co.,Ltd.,Dalian 116319,China)

机构地区：[1]辽宁红沿河核电有限公司,辽宁大连116319

出　　处：《电力学报》2022年第1期58-65,共8页Journal of Electric Power

摘　　要：核电站汽轮机通常采用体积较大的半速汽轮机,由于体积和重量较大,轴系找中心工作难度较大。核电汽轮机轴系中心偏差作为影响汽轮机运行状态的关键参数,在检修中需要予以严格的控制,如中心偏差过大会导致轴瓦载荷过大、振动增加、应力增大等严重后果。为了定量的分析汽轮机轴系中心偏差对汽轮发电机组短期运行参数和长期寿命的具体影响,通过对汽轮机单个转子和多转子轴系进行建模,用有限元分析软件计算单个转子在重力作用下的挠度曲线及联轴器位移,据此计算多转子的挠度曲线,从而说明对中的原理。使用有限元计算软件对不同外圆和张口中心偏差下的轴系状态进行计算,得出各种中心偏差下的轴承载荷和转子应力,定量地分析了轴系中心偏差对机组运行状态的影响。对历史检修过程的轴系中心数据和检修前后的机组状态进行了分析,结合计算数据,确定了轴系中心偏差对轴瓦载荷、轴系振动、部件应力和疲劳老化等的影响。通过分析发现外圆偏差对相邻轴瓦的载荷影响较大,对间隔的轴瓦载荷影响较小;随着外圆偏差的增大,等效应力值不断增大,联轴器应力最大值在轴瓦与转子接触的承载面附近;张口偏差对各个轴瓦载荷的影响基本一致,对相邻轴瓦的载荷影响与间隔的轴瓦影响大小一致,方向相反。相对于同样大小的外圆偏差,张口偏差对轴瓦载荷的影响明显偏小。随着外圆偏差的增大,等效应力值不断增大,联轴器应力最大值在轴颈和对轮连接处。Nuclear power plant steam turbine usually adopts half speed steam turbine with large volume.Due to large volume and weight,it is difficult to find the center of shafting.As a key parameter affecting the operation state of steam turbine,the center deviation of steam turbine shafting needs to be strictly controlled in maintenance.For example,excessive center deviation will lead to excessive bearing load,increased vibration,increased stress and other serious consequences.In order to quantitatively analyze the specific impact of steam turbine shafting center deviation on short-term operation parameters and long-term life of steam turbine generator unit,the single rotor and multi rotor shafting of steam turbine were modeled,the deflection curve and coupling displacement of a single rotor under gravity were calculated by finite element calculation software,based on this,the multi rotor shafting deflection curve were calculated,which explain the principle of alignment.The shafting state under different outer circle and opening center deviation was calculated by finite element analysis software.The bearing load and rotor stress under various center deviations were calculated.Thus,the influence of shafting center deviation on the operation state of the unit was quantitatively analyzed.By analyzing the shafting center data in the historical maintenance process and the operating state before and after maintenance,combined with the calculated data,the effects of shafting center deviation on bearing load,shafting vibration,component stress and fatigue aging were determined.Through the analysis,it was found that the outer circle deviation has a great influence on the load of adjacent bearing shells and a small influence on the spaced bearing shells.With the increase of the outer circle deviation,the equivalent stress increases continuously,and the maximum stress of the coupling was near the bearing surface between the bearing bush and the rotor.The influence of opening deviation on the load of each bearing bush was basically t

关 键 词：轴系中心 有限元计算 轴瓦载荷 轴系振动 部件应力 

分 类 号：TK268[动力工程及工程热物理—动力机械及工程]