浮头式换热器换热管轴向压应力校核不合格的解决方法

Solution to Unsatisfactory Axial Compressive Stress Checking of Heat Transfer Tube of Floating Head Heat Exchanger

在浮头式换热器的计算过程中,若壳程设计压力较高,可能出现管板最小厚度下换热管轴向压应力校核不合格,此时可采用适当的方法,提高换热管在设计工况下的稳定许用压应力[σ]tcr或降低换热管的轴向压应力σt来进行调整。文章主要介绍了两种具体方法,即减小换热管受压失稳当量长度lcr和增加管板厚度。通过分析校核不合格时的实际情况,分别简述了该两种方法的适用情况和具体措施,并说明了各自利弊,为今后类似设计提供借鉴。

In the calculation process of floating head heat exchanger,if the design pressure of shell is high,there may be unsatisfactory axial compressive stress check of heat transfer tube under minimum thickness of the tube sheet. At this time,appropriate method can be used to improve the stable allowable compressive stress[σ]t crof heat transfer tube under the design conditions or reduce the axial compressive stress σtof heat transfer tube to make adjustment. The paper mainly introduces two specific methods,i.e.to reduce the equivalent length lcrof tube against buckling and increase the thickness of tube sheet. By analyzing the actual condition for checking failure,this paper briefly describes the application of the two methods and the specific measures,and explains their respective pros and cons,which can provide reference for future similar design.