奥氏体不锈钢应变强化型移动式深冷容器的强度分析与结构优化

发布时间：2018-09-08 10:14

【摘要】：采用应变强化技术可使奥氏体不锈钢深冷容器壁厚减薄,实现结构轻量化。目前我国已将该技术用于固定式深冷容器中,但是尚未用于移动式深冷容器,这主要是缺乏相关基础研究,对该技术用于移动式深冷容器存在耽心。本文以奥氏体不锈钢应变强化型移动式深冷容器为研究对象,分析强化工艺参数的确定方法,基于韧性断裂和疲劳断裂的失效模式,利用非线性有限元数值模拟的方法对其进行设计校核,并对内容器支撑区域的补强结构开展参数化分析,主要完成的研究工作及结论如下:(1)针对移动式压力容器的结构特点,内容器应变强化条件下的塑形变形不宜过大。根据材料真实的力学性能,提出了该类容器应变限制条件ε=min {ε410,5%},进而选取合适的强化应力值Rk=min{410MPa,σ5%},由修正公式计算得到强化压力值Pk。(2)针对一典型移动式压力容器开展数值模拟研究,通过分析不同工况下容器的受力情况,发现最大Mises等效应力值都出现在固定端支撑区域的加强圈上,超过奥氏体不锈钢材料在室温下的许用应力值,存在一定的安全隐患。(3)基于韧性断裂和疲劳断裂失效模式,对该容器进行强度校核。有限元分析结果表明容器在正常的服役过程中不会发生塑性垮塌、局部失效和疲劳破坏。(4)研究了加强圈的结构形式、布置方式以及筒体局部加厚结构参数对容器应力的影响规律。对比加强圈与筒体局部加厚这两种补强结构形式对容器应力分布的影响,结果表明后者更利于改善容器的受力情况。
[Abstract]:The wall thickness of austenitic stainless steel cryogenic vessel can be thinned by strain strengthening technique and the structure is lightweight. At present, the technology has been used in the stationary cryogenic container, but it has not been used in the mobile cryogenic container. This is mainly due to the lack of related basic research, so there is concern about the application of this technology in the mobile cryogenic container. In this paper, an austenitic stainless steel strain-strengthened mobile cryogenic vessel is studied. The determination of strengthening process parameters is analyzed based on the failure modes of ductile fracture and fatigue fracture. The nonlinear finite element numerical simulation method is used to design and check it, and parameterized analysis is carried out for the reinforced structure of the inner support area. The main research work and conclusions are as follows: (1) according to the structural characteristics of mobile pressure vessels, The plastic deformation should not be too large under the strain strengthening condition. According to the real mechanical properties of the material, the strain limiting condition of this kind of vessel, 蔚 / min {蔚 410mg / 5%}, is put forward, and then the appropriate strengthening stress value Rk=min {410MPa, 蟽 5%} is selected, and the strengthening pressure value Pk. (2) is calculated by the modified formula and the numerical simulation is carried out for a typical mobile pressure vessel. By analyzing the stress of the vessel under different working conditions, it is found that the maximum effect force of Mises appears on the reinforcing ring of the fixed end bracing area, which exceeds the allowable stress value of austenitic stainless steel material at room temperature. (3) based on the failure mode of ductile fracture and fatigue fracture, the strength of the vessel is checked. The results of finite element analysis show that plastic collapse, local failure and fatigue failure will not occur during the normal service of the vessel. (4) the structural form of the strengthened ring is studied. The influence of layout and local thickening structure parameters on vessel stress. By comparing the influence of the two kinds of reinforcing structure forms on the stress distribution of the vessel, the results show that the latter is more favorable to improve the stress situation of the vessel.
【学位授予单位】：华东理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TH49

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