椭圆封头与筒体过渡段应力分布  

Study on stress distribution at transition section between elliptical head and cylinder

作　　者：刘红姣[1] 刘喆 唐柳华 林雪慧[1] LIU Hongjiao;LIU Zhe;TANG Liuhua;LIN Xuehui(Institute of Intelligent Manufacturing,Jianghan University,Wuhan 430056;Wuhan Guokong Technology Co.,Ltd.,Wuhan 430084)

机构地区：[1]江汉大学智能制造学院,湖北武汉430056 [2]武汉过控科技有限公司,湖北武汉430084

出　　处：《机械设计》2023年第8期42-49,共8页Journal of Machine Design

基　　金：武汉市应用基础前沿项目(2020010601012291)。

摘　　要：在中低压容器常规设计中,对椭圆封头与筒体过渡段的边缘应力一般不予计算,只在结构上进行局部处理。为了探究边缘应力对椭圆封头及筒体过渡段的影响,文中针对5种不同直径的椭圆封头,采用ABAQUS有限元分析软件和有矩理论,对比研究了封头过渡段内外壁面应力的变化规律,同时采用有矩理论研究了封头过渡段内外壁面边缘应力的影响范围及最大值出现的位置。结果表明:5种不同直径封头直边段内外壁面存在大小相等、方向相反的边缘应力,内外壁面最大径向边缘应力与筒体薄膜应力相当,最大值至连接处的距离远大于椭圆形封头标准规定的直边高度,直径越大,距离越远。封头标准GB/T 25198—2010中规定直边高度处径向应力超出筒体薄膜应力的44%~61%。直边段与筒体薄膜应力相当的横截面距连接处0~15 mm,与直径关系不大。研究结果可对中低压容器的设计制造和安全运行起到一定的指导作用,为封头标准的修订提供参考依据。Generally,the edge stress at the transition section between the elliptical head and the cylinder is not calculated in the conventional design of medium-and low-pressure vessels.Instead,structural improvement is made on some parts.In this article,as for the five elliptical heads with different diameters,the finite-element software ABAQUS and the moment theory are used to analyze the change of the edge stress on the inner and outer walls at the transition section;the moment theory is adopted to explore the influencing range of the edge stress on the inner and outer walls at the transition section as well as the position of the maximum value.The results show that there are edge stresses of equal size and opposite direction on the inner and outer walls at the straight edge sections of the five heads with different diameters.The maximum meridional edge stress on the inner and outer walls is equivalent to the stress on the cylinder membrane,and the distance from the maximum value to the connection is much greater than the straight edge height specified by the elliptical-head standard.The larger the diameter,the farther the distance.The meridional stress on the straight edge height specified in the elliptical-head standard GB/T 25198—2010 exceeds the stress on the cylinder membrane by 44%~61%.The section where the stress on the straight edge section is equivalent to that on the cylinder membrane is 0~15 mm away from the connection,which is not closely related to the diameter.This study provides guidance for design,manufacturing,and safe operation of medium-and-low pressure vessels,and offers reference for revision of head standards.

关 键 词：椭圆封头 直边高度 有限元分析 有矩理论 边缘应力 

分 类 号：TH123[机械工程—机械设计及理论]