【作者】 李海宽；

【导师】 齐二石； 杨立峰；

【作者基本信息】 天津大学 ， 工业工程， 2008， 硕士

【摘要】 拱顶罐是一种常见的大型储罐,其主要的失效形式是拱顶失稳。本文针对华北石化公司罐405拱顶罐拱顶失稳,应用外压失稳理论分析获得其失稳原因:罐内负压超过一阶临界荷载,致使罐顶失稳变形。综合比较检修法、正压法等几种拱顶修复方法,针对405罐失效的实际情况,选取注水正压法进行修复。修复过程注意防止外界温度造成罐内压力变化,注水不宜过快。为防止焊缝拉裂,修复前应进行局部加强。进行上举力、罐顶环向应力校核,确保储罐安全修复。通过运用网络技术法对渣油罐拱顶维修工程的路线进行优化,提出在正压法修复后局部采用机械吊拉法进行修复的建议,确保维修工期合理规划、降低了成本费用。并对渣油罐拱顶维修成本进行了分析,通过改善网络计划,得到最优方案并付诸实施,对生产实际有重要的指导意义。更多还原

【Abstract】 Dome roof tank is a common large storage tank and its main failure mode is dome roof instability. According to 405tanks’s roof instability in North China Petrochemical Corporation, this paper utilized the external pressure instability theory to analyze and get the reason is that the tank negative pressure exceeded the first order critical load to cause the dome roof’s deformation. A comprehensive comparison has been made between repairing method and positive pressure method to select the water injection positive pressure method to restore 405tank according to the real situation of the tank. ANSYS software has been explicated to establish the dome roof tank’s mechanical model to check the instability and analyze the intensity under inner pressure. The finite element model of the instable tank has been established using node method to analyze the stress during the restoring process, pointing out that positive pressure method is feasible to restore the instable tank in case of less serious deformation. During the repairing process, external temperature change should be paid more attention to prevent the change of tank’s inner pressure. Water injection should not be too fast, and when the inner pressure is greater than 0.5 times of the first order instability critical load, water injection speed should be reduced. To prevent the seam fracturing, partial strengthening should be carried out before the restoration. Uplift force and dome roof hoop stress should be checked to ensure a safe restoration. This paper presents a method to improve the critical load and safety repair measures which is an important guiding significance to actual production.更多还原