摘要
根据力平衡原理分别按弯管的内外拱方向和中性线方向推导出内压下弯管的两条环向应力公式,针对两条公式相似而又有明显区别的问题,通过内拱区与外拱区的环向应力大小定性比较分析,发现前者较后者所反映的环向应力分布呈内拱大外拱小的不平衡状态程度更大,通过环壳内压爆破实验结果远低于理论值的定量比较对此证实。结论认为,内压作用下的弯管结构属于有力矩旋转壳,整体环壳第二弯曲半径由外拱区的正半径变化为内拱区的负半径,引起应力性质的变化,只考虑薄膜应力的弯管内压爆破理论存在不安全的因素。
Two formulas of circular stress of bend are inferred according to the force balance theory both on the intrados- extrados direction and the flank - flank direction respectively. But two similar formulas are much different. It is found that the former provide more uneven circular stress state than the latter after comparing the circular stresses both of intrados and extrados, which extrados stress is large and intrados stress is small. That is confirmed by the results of experiment that the practical burst pressure is far smaller than the theory burst pressure. The bend structure belongs to rotate shell with moment under internal pressure. The second bend radius of ring would change from positive shell to negative shell between extrados and intrados, and the stress character should change too. There is danger factor in the burst pressure theory if membrane stress is considered only.
出处
《压力容器》
北大核心
2006年第2期38-41,共4页
Pressure Vessel Technology
关键词
弯管
环壳
负壳
环向应力
bend
ring
negative shell
circle stress
作者简介
陈孙艺（1965-），男，教授级高级工程师，现任茂名石化机械厂副厂长兼总工程师，从事压力容器设计审定、制造工艺、失效分析及技术管理，通讯地址：广东茂名市环市西路91号，中国石化茂名石化机械厂。
