锅炉过热器管道应力分析及改造方案

The Stress Analysis and Alteration Scheme of Superheater Pipes

用Ansys软件对某600 MW锅炉分隔屏过热器的应力进行了分析计算,并根据实际情况用3种不同的物理模型进行计算比较,得出了相应的结果。同时用Goodman图解法评估分隔屏的安全性,发现屏晃动单侧值在0.3 m内时,3种方案中最大应力幅值在60.3 MPa以内,过热器屏是安全的,若屏晃动单侧值超过0.4 m,应力幅值将超过80 MPa,超过了锅炉所能承受的应力极限78 MPa。进而提出了改造方案,以限制在运行中锅炉屏式过热器之间发生晃动。改造后经初步计算,其最大应力达到安全范围。

The Ansys software is applied to calculate cycle stress of front screen superheaters for 600 MW generating sets which is simulated by three different models, and evaluate its security with Goodman diagrammatize methods. The results show that screen superheaters are secure under the conditions that the shake single peak value is less than 0.3 m then its Von Mises stress is no more than 60.3 MPa. In the view opinion of boiler total life period if screen shake over 0.4 m or stress exceeds 80 MPa, there is a risk of tube explosion or other serious fault. Therefore, an improvement scheme is proposed to limit the screen shaking. Then its stress achieve the margin for safety through calculates.