炼化汽包的热应力及强度分析

目的针对余热锅炉技术标准两条技术路径的选择问题,分析热应力对汽包强度的影响。方法在比较了炼油化工余热锅炉特点的基础上,以某汽包参数为例,分别按压力容器和锅炉两种技术标准计算其各项应力和总应力。结果汽包按锅炉标准计算的轴向总应力最大达84.458 MPa,比按压力容器标准计算的轴向总应力37.521 MPa高出125%,汽包接管内角处按压力容器标准计算的环(周)向总应力为257.3 MPa,略高于按锅炉标准计算的244.16 MPa,只高出5.4%,而按压力容器标准计算的径向总应力与按锅炉标准计算的径向总应力相等,总的来说,汽包各项总应力未达到各自结构材料的应力许可限度。结论汽包可以不按锅炉标准设计,监察规程关于余热锅炉汽包设计标准路径选择的条款规定合理可靠。

Thermal Stress and Strength of Steam Drum in Petroleum Refining

Objective To analyze how thermal stress affects the strength of steam drum in allusion to selection of two kinds of technology standards on waste heat boiler. Individual stress and total stress of steam drum were calculated according to pressure vessel standard or boiler standard respectively, based on comparing structural features of waste heat boiler in petroleum refining. Results The total axial stress of steam drum calculated according to boiler standard was 84.458 MPa, the total axial stress calculated according to pressure vessel standard was 37.521 MPa, the former was 125% greater than the latter. Total hoop stress at inside angle of tube calculated according to pressure vessel standard was 257.3 MPa, 5.4% more than 244.16 MPa, which was calculated according to boiler standard. In general, the total stress of each kind was less than the allowance stress of structure material. Conclusion The drum of case may not be designed according to boiler standard. The terms of supervision regulation on how to select design standard of steam drum of waste heat boiler are reasonable and reliable.