The domestically produced full-position automatic welding system has achieved a new breakthrough in the welding of nuclear power VVP pipelines.

At 15:00 on May 10, 2019, with the strong promotion of China Nuclear Power Engineering Company, and the organization and implementation by 23rd Company of China Nuclear Construction Company, Beijing Leiming Cyber Mechanical and Electrical Technology Co., Ltd. provided complete equipment and welding process support. The domestically developed automatic welding system independently developed by Beijing Leiming Cyber Mechanical and Electrical Technology Co., Ltd. was applied for the first time in the VVP pipeline welding of Unit 5 of Tianwan Nuclear Power Plant.

(SmartArc-400TD Welding System Picture)

Present at the site were Luo Jing (Chief Engineer) from the Lianyungang Project Department of China Nuclear Second and Third Construction Company, Yu Yingjie (Assistant Manager of the Pipeline Team), Gao Jun (Director of the Welding Technology Department), the quality assurance department representative, and the personnel from the supervision company.

(Picture of the personnel from the Lianyungang Project Department of Zhonghe Second and Third Construction Co., Ltd. who visited the site)

(VVP Pipeline Welding Room Number Picture)

All nuclear power workers are aware that during the operation of the secondary circuit VVP main steam system pipelines, if there is a steam leakage in the conventional island, it will affect personal safety and the safety of the surrounding environment. Moreover, these pipelines cannot be isolated during operation, and if a leakage occurs, it may lead to a series of problems such as reduced power output, shutdown, and reactor shutdown. Therefore, strictly controlling the welding quality is the top priority in VVP pipeline welding. Compared with the traditional manual welding of VVP pipelines in the past, the groove processing and weld dimensions are larger, the amount of welding material filled is greater, and it is difficult to control the deformation amount. The work intensity is high, and the training cost for welders is also high. The application of the VVP pipeline automatic welding system has solved these problems. At the same time, it has shortened the training time for enterprise welders and saved costs.

(Manual welding pictures of VVP pipeline)

The automatic welding team for the VVP pipeline of Unit 5 of the No. 5 reactor consists of Chen Zhongzhou (the chief welding technician) from the Welding Technology Department of the Lianyungang Project Department of China Nuclear No. 2 and No. 3 Construction Co., Ltd., Pang Hu (the automatic welding operator) from the EM2 team, Yang Xiaocheng (the director of the welding laboratory) from CBE Company, and Liu Jianyou (the after-sales process engineer).

(Automatic Welding Team Photo)

(Internal observation of weld penetration image)

(External molding image)

(Internal molding image)

On May 11, 2019, the transition layer was completed and there were no defects in the RT inspection between the weld layers, achieving a one-time qualified result.

(Transition layer formation image) (Radiation qualification report image)

Thanks to the concerted efforts of the VVP pipeline welding team, strict requirements, and the strong support of the project management team of China National Nuclear Corporation's Second Third Construction Co., Ltd. in Lianyungang, the first weld joint of the VVP automatic welding for Unit 5 was successfully completed and sealed on May 16, 2019 at 11:32. The total welding time was 4 days. The RT inspection was free of defects and achieved one-time qualification. The weld seam was well formed. This has won unanimous praise from the customers.

The successful application of the domestic fully-featured automatic welding system by Beijing Leiming Cyber Electromechanical Technology Co., Ltd. has significantly reduced the labor intensity of traditional manual welders in nuclear power plants, as well as the harm caused by smoke and arc light.

High-quality welds have provided new ideas for traditional welding methods, embodying the spirit of "Chinese Innovation" and contributing to the development of China's nuclear power industry.