The nuclear island of Unit 1 of Haoyang Nuclear Power Plant will undergo a cold test on June 20th. This is a significant milestone in the progress of the first batch of AP1000 units. A few days ago, Westinghouse of the United States proposed a design change: modifying the geometric dimensions of the sealing surface of the manhole door of the residual heat removal heat exchanger. The residual heat removal heat exchangers of Units 1 and 2 of Shandong Haoyang Nuclear Power Plant have been installed, and the modification of the manhole sealing surface dimensions must be measured on-site and machined on-site. However, Dongfang Zhongji, the manufacturer of the residual heat removal heat exchangers of Haoyang Nuclear Power Plant, does not have the capability for on-site machining. Once again, a situation of tight schedule and heavy tasks has emerged. 

On June 1st, the State Nuclear Engineering Co., Ltd. organized a four-party teleconference involving the owner of Haoyang Nuclear Power Plant, the pressure vessel manufacturer Dongfang Electric (Guangzhou) Heavy Machinery Co., Ltd., and Beijing Leiming Cyber Mechanical Technology Co., Ltd. The meeting proposed to ensure the smooth progress of the cold test of Unit 1 on June 20th. It was required that the sealing groove processing task for the upper head of Unit 1 must be completed by June 14th. At the meeting, the relevant leaders of State Nuclear Engineering made a decisive decision based on the preliminary plan of Leiming Cyber. Dongfang Heavy Machinery and Leiming Cyber cooperated closely to formulate a project action plan: 

On June 2nd, Raymond Cyber submitted the "Supplier Qualification Documents", "Construction Plan" and "Quality Plan", and completed the on-site measurement and the preparation of processing equipment. 

On June 3rd, Dongfang Heavy Machinery completed the document review, handled the relevant procedures, and dispatched the fabricated mock-ups to Leiming Cyber. 

From June 4th to 5th, Raymon Cyber completed the process test. Personnel from China Nuclear Engineering and Dongfang Heavy Machinery were present to witness the process and determine the process parameters of the "Construction Plan". 

On June 6th, Raymond Cyber dispatched personnel to inspect the construction site in Haoyang and completed the preparation of the on-site support system within one day. 

On June 8th, the Raymond Cyber construction team entered the construction site in Haoyang. 

By June 14th, Raymond Cyber will complete the processing of the sealing surface of the manhole on the 1# machine. 

After the meeting, the relevant personnel from all four parties immediately took action, following the plan set by the meeting and working in parallel while cooperating with each other. 

On June 3rd, the National Nuclear Engineering organization held another four-party teleconference. The meeting reviewed the implementation of the plan and, together with Dongfang Zhongji, provided review opinions on the construction plan and quality plan of Leiming Sibao. On that day, Leiming Sibao completed the upgrading of the "Construction Plan" and "Quality Plan" and received approval. At the same time, the construction equipment of Leiming Sibao that was urgently airlifted from Shanghai arrived at the Beijing base as well. 

On June 3rd, the mock body of Dongfang Heavy Machinery was completed. That night, it was delivered to Beijing by air as scheduled. The witnessing experts from both the National Nuclear Power Corporation and Dongfang Heavy Machinery also arrived in Beijing on time. 

On June 4th, under the supervision of the personnel from China Nuclear Engineering and Dongfang Heavy Machinery, Leiming Sibo successfully completed the 1:1 mock-up processing test. The final assessment of the processing plan in the "Construction Plan" was also completed. 

On June 5th, the project manager dispatched by Raymond Cyber arrived at the Haoyang site and conducted an on-site inspection. 

On June 6th, with the cooperation of the Shandong Nuclear Power and the National Nuclear Engineering On-site Coordination Office, the Fifth Construction Company of China National Nuclear Construction completed the preparation of the on-site support system as requested by Remon Cyber. 

On June 7th, members of the Raymond Cyber Engineering Team set off from Beijing and took a special vehicle to visit the Haiyang Nuclear Power Plant in Shandong Province. 

After the factory training on June 8th, we entered the site and implemented the anti-particle intrusion measures as required by the nuclear power industry. We followed the "Construction Plan" to adjust and position the flange processing machine. 

On June 9th, under the witness of the owner, CGN Engineering and Dongfang Heavy Machinery, the personnel of the Raymond Cyber Engineering Team conducted the measurement and turning of the sealing surface of the manhole flange of the residual exhaust heat exchanger on a temporary workbench that was 1.8 meters high, 1.2 meters long and 0.8 meters wide. The construction process strictly followed the requirements of the "Construction Plan" and the "Quality Plan", including measurement, processing, measurement, inspection and witnessing. The 1# reactor head sealing groove turning work was completed ahead of schedule by 12:00 noon. In the afternoon, the supervisory personnel from the owner of Haier, CGN Engineering and Dongfang Heavy Machinery conducted a strict inspection of the processing results and reached a conclusion of full compliance with the design requirements. Thus, a "time-pressed and task-heavy" battle to ensure the timely cold test of Haier Nuclear Power was successfully completed two days ahead of schedule. 

The engineering professionals from China Nuclear Engineering, Dongfang Heavy Machinery and Beijing Leimansai Mechanical and Electrical Technology Co., Ltd. demonstrated excellent service spirit, efficient coordination ability, superb engineering technology and perfect task results in this project. These achievements presented a rich gift to the traditional Chinese festival, the Dragon Boat Festival. 

During the Dragon Boat Festival, the on-site engineering team members of Raymond Cyber moved to the 2# nuclear island in Haoyang and began the work of modifying the manhole flanges of the residual heat removal heat exchanger in the 2# nuclear island. Wish them a safe and smooth Dragon Boat Festival!