低温液体罐车外壳加强圈削边后的稳定性计算

Stability Calculation of Outer Jacket of Road Tankers for Cryogenic Liquid with Reinforcement Rings Partly Cut-off

低温液体罐车的外壳(也即外筒体)为真空容器,外设多个加强圈以增强其抗失稳能力,但为了提高装载量并且不突破罐车的宽度限制,往往对加强圈两侧进行削边处理。由于削边后结构不规则,无法再按照GB 150—2011《压力容器》进行失稳临界压力或许用外压计算。为此,提出了加强圈刚度削弱系数的概念,并在有限元分析的基础上,拟合出了加强圈刚度削弱系数表达式。有了该系数,就可以在按照GB 150—2011进行常规设计的基础上,解决低温液体罐车外壳加强圈削边后的失稳临界压力计算问题。

The outer jacket of road tankers for cryogenic liquid is a vacuum pressure vessel.Multiple rein-forcement rings are required to enhance its capability of anti -instability.However,in order to increase the geometrical volume of the inner vessel without exceeding the width limitation on the vehicle,the rein-forcement rings are usually cut -off on both sides of the jacket.Thus,the reinforcement rings are no lon-ger regular in structure and the code of GB 150—2011 can not be directly applied to calculate the critical pressure or the allowable outside pressure.A so -called stiffness weakening coefficient of the reinforce-ment ring is defined and expressed based on the numerical calculations of the critical pressure of the outer jacket with the reinforcement rings partly cut -off.With the stiffness weakening coefficient,the stability of the outer jacket with partly cut -off reinforcement rings may be calculated according to GB 150—2011, and thus,the design of the road tankers for cryogenic liquid can be greatly simplified.