内压圆筒厚度计算公式分析讨论

Discussion on Thickness Formula of Cylindrical Shell Under Internal Pressure

GB 150—2011中采用的是弹性失效准则,规定对设计压力p≤0.4[σ]t的内压圆筒厚度按中径公式进行设计。JB 4732—1995中规定对设计压力p≤0.4[σ]t的内压圆筒厚度按中径公式进行设计,设计压力p>0.4[σ]t时按Tresca全屈服压力进行设计。比较研究表明:基于弹性失效准则时,中径公式算出的厚度最薄;基于塑性失效准则时,中径公式算出的厚度最厚;当径比较小时,按Tresca全屈服压力和中径公式算出的内压圆筒厚度相差很小,在工程设计中,可以统一采用Tresca全屈服压力计算内压圆筒壁厚。

Elastic failure criterion is adopted in GB formula based on middle radius equation is useful for pressure is no more than 0. 4 [σ]＇Ф. JB 4732--1995 150--2011, which stipulates that the wall thickness cylindrical shell under internal pressure if the design also adopts the wall thickness formula based on mid- dle radius equation if the design pressure is no more than 0. 4 [σ]＇Ф, otherwise, the wall thickness ac- cording to Tresca limit pressure should be used. The authors find that the thickness based on middle radi- us equation is the thinnest one when elastic failure criterion is used. However, the result is opposite when plastic failure criterion is used. The difference between the calculated thicknesses in accordance with mid- dle radius equation and Tresca limit pressure is small when its diameter ratio is small. This means that the wall thickness formula based on Tresca limit pressure can be used for both thin and thick cylindrical shells in engineering design.