核电主管道制造工艺发展

Development of nuclear power main-pipe manufacturing technology

核电主管道是核岛中关键部件之一。美国西屋公司推出的第3代核电技术AP1000要求核电主管道的使用寿命达到60年,且要求管身不能出现焊缝,因此对传统的核电主管道制造方法提出了挑战。目前国内制造AP1000核电主管道的方法是采用实心铸坯,用自由锻方法成形带有互成角度的接管嘴凸台实心轴坯,再通过机加工成形主管道的内孔。该机加工方法存在材料利用率低、生产工期长以及质量不稳定等特点。本文针对核电主管道成形工艺的发展进行分析,提出了一种基于镦挤工艺的第3代核电主管道成形方法。数值模拟分析结果表明,与目前采用的主管道成形方法相比,该方法具有节省材料、生产效率高及管道质量好等优点。

Nuclear power main-pipe is one of the key parts in nuclear island. The third generation nuclear power technique AP1000 devel- oped by Westinghouse requires that the design lifetime of nuclear power main-pipe is 60 years, and no welding seam is allowed on the pipe body. Thus those conventional manufacturing techniques of nuclear power main-pipe face serious challenges. Currently, the method to manufacture AP1000 nuclear power main-pipe in Chinese industry is that the solid ingot casting is used to be initial billet, and then a solid spindle blank with both angled nozzle-like bosses is formed through free forging process, followed by machining performed to obtain the in- ner cavity of main-pipe, which is characterized by lower material utilization, longer production cycle and unstable quality of product. The history of nuclear power main-pipe manufacturing technology was reviewed. A new nuclear power main-pipe for AP1000 manufacturing technique based on upset-extruding technique was introduced. Numerical simulation analysis indicates that the new technique has advantages such as material saving, high-efficiency and better inner quality of product over conventional techniques for forming main-pipe.