【作者】 王雪骄；

【导师】 童彦刚； 郑建能；

【作者基本信息】 重庆大学 ， 材料工程， 2008， 硕士

【摘要】 在石化行业加氢反应器制造过程中,弯管的内壁堆焊是整个产品制作过程中的难点之一。目前的弯管制作方法,将90°弯管均分为三段,分别进行内壁堆焊后装配焊接为一整体,再进行对接环缝的补堆,其加工、成型、堆焊、装焊工序较多,生产效率低且堆焊质量不易保证。为此,已有专家提出了采用弯管内壁堆焊层先堆焊再一起进行弯制的思路,但该思路能否顺利实现,还取决于在弯管内壁堆焊层先堆焊后依次经高温热成型、调质处理、最终热处理后,其化学成分、力学性能、抗晶间腐蚀等性能是否能满足技术条件要求。本文正是从这种思路出发,采用在试板上模拟弯管先堆焊再进行弯制的方法,研究探讨采用一种新的弯管制造工艺的可行性。2.25Cr-1Mo钢加氢反应器弯管堆焊工艺及性能的初步研究结果表明:①2.25Cr-1Mo钢上E309L+E347双层不锈钢堆焊层依次经高温热成型、调质处理、最大热处理后存在裂纹敏感性,而这种弯曲裂纹敏感性是由焊缝结晶偏析引起的。②本文采用的堆焊方法和堆焊工艺使2.25Cr-1Mo钢上E309L+E347双层不锈钢堆焊层依次经高温热成型、调质处理、模拟最大热处理后仍能满足抗晶间腐蚀的性能,并获得满足技术条件要求的化学成分均匀的堆焊层组织。③性能热处理应采用水淬和高温回火的工艺,以确保能获得最佳冲击韧性的显微组织,并避开不锈层475～650℃敏化温度的最敏感区。截至目前为止,关于2.25Cr-1Mo钢加氢反应器弯管先堆焊内壁层再进行弯曲成型的制造工艺尚未见报道,本研究为这种新型的制造方法的实施和不断完善,打下坚实的理论和实践的基础。更多还原

【Abstract】 For hydroprocessing reactors used in petrochemical industry, it is difficult to provide high quality cladding in the inboard wall of bended pipes. Traditional manufacture method make bended pipe to cut into three parts, before putting these parts into a whole, cladding layer must be cladded in the pipe. This method’s working procedure are more, including processing, molding, cladding, assembly, welding and so on. In addition, its efficiency is low and welding quality is difficult to guarantee. For these reasons, there is a new method that is to cladding in pipe before the pipe is bended. But there is a question in this method, Wether does the cladding layer’s capability can meet technology’s require in chemical composition, mechanical properties, resistance to intergranular corrosion, and so on. So, we adopt the method that is cladding on the board before bending to simulate the making course of the bending pipe, try to find out the rule of this kind of manufacture method, in order to reduce too many returning working procedure.This thesis shows that:①The E309L+E347 caldding layer on 2.25Cr-1Mo steel has cold bending crack sensitivity after heat bending, quaching and tempering, Max PWHT. The crack sensitivity is from segregation of crystal.②Using this cladding method and technology can make the cladding layer have the resistance to intergranular corrosion and even chemical composition.③It should adopt water quenching and tempering with high temperature in the heat treatment of performance, in order to guarantee to obtain the micro-organization with the best impact toughness, and avoiding the section of 475- 650℃sensitization temperature to stainless steel.Up to now, there is no report on this new method of hydroprocessing reactors’s bending pipe. The result of study has offered the scientific data for the method amelioration of hydroprocessing reactors’s bending pipe and established the solid foundation.更多还原