As the weak link of the strength of glass - lined equipment, glass - lined coating is not given more attention to during the design of glass - lined equipment. Combined with the failure phenomenon of glass -lined equipment appearing in the manufacturing and operating process,with the help of finite element method and destructive test, the allowable stress of glass - lined equipment was discussed preliminary. The result indicates that the strength check based on the single primary membrane stress can not guarantee the safety of glass - lined equipment and the maximum principle stress of glass - lined coating should also be taken into consideration. Usually the maximum principle stress of glass - lined coating appears at the same position as the global membrane stress of metal base and is slightly higher than the global membrane stress of metal base. Therefore, the strength of both metal base and glass - lined coating should be considered and 1.2-1.5 times of global membrane stress can be chosen as the maximum principle stress of glass - lined coating to check its strength. Meanwhile, the structure of the zone with high stress can also be optimized to decrease the stress level of metal base and glass - lined coating.%搪玻璃层是搪玻璃设备的强度薄弱环节,但现有设计大都仅考虑了金属基体的强度,对搪玻璃层的强度没有关注.结合搪玻璃设备制造和运行中常常出现的裂纹或爆瓷等现象,借助有限元分析法和破坏性试验测试,初步探讨了搪玻璃设备的许用应力.结果表明,单纯依靠金属基体的总体薄膜应力进行搪玻璃设备的强度校核并不能确保搪玻璃层的安全,还必须考虑搪玻璃层的最大主应力.一般搪玻璃层的最大主应力出现在与金属基体最大主应力相同的位置,且搪玻璃层的最大主应力略高于金属基体的总体薄膜应力.故实际设计中必须同时兼顾金属基体和搪玻璃层的强度,并取1.2～1.5倍的金属基体总体薄膜应力作为搪玻璃层的最大主应力进行校核为宜,同时对设备高应力区还有必要通过结构优化来降低金属基体与搪玻璃层的应力水平.
展开▼
