应变强化型移动式低温压力容器的安全性分析

The safety analysis of strain-strengthening mobile cryogenic pressure vessel

对于移动式低温压力容器,应变强化技术可使内容器壁厚减薄,但也会导致不连续区结构应力增加,筒体中部发生较大的塑性变形,如何有效评估该类容器的安全性,是科学界及工程界都迫切需要解决的问题。以应变强化型移动式低温压力容器为研究对象,采用非线性有限元方法对该容器进行数值模拟,利用弹塑性分析方法对内、外容器进行强度校核。分析结果表明,该结构符合安全要求,筒体中部相比于其他部位塑性变形量大,易发生塑性垮塌和局部失效,应该合理的布置加强圈,增加结构的安全性。

For mobile cryogenic pressure vessel, the wall thickness of inner container can be reduced by using strain - strengthening technology. However, the stress on the discontinuous zone increases due to wall thickness reduction. How to effec- tively evaluate safety of the vessel is an urgent need for the scientific and engineering communities. Taking the strain - strengthe- ning mobile cryogenic pressure vessel as research object, the vessel was simulated by using nonlinear finite element method. The internal and external containers were checked by using elastoplastic analysis method. The analysis results showed that the struc- ture met safety requirements. Plastic deformation occurred in the middle of cylinder body, which was large and prone to plastic collapse and the local failure compared to other parts of the vessel. Stiffening ring should be arranged rationally, which could in- crease the safety of the structure.