Sinotrans Sarens has completed a 29.600-tonne converter station topside weighing operation for ZPMC Nantong as part of the Yangjiang Sanshandao 500 kV Offshore Wind Project.
The one-day operation provided weighing data for the subsequent transport and installation of the topside and for structural safety control. The result exceeded Sarens’ earlier weighing of more than 28.000 tonnes for the Three Gorges Yangjiang Qingzhou Converter Station.
Named “Haifeng Heart”, the converter station has an installed capacity of 2 GW and uses a ±500 kV flexible direct-current transmission system for offshore wind applications. The converter station is described as the world’s largest offshore wind converter station.
Once completed and operational, the project is expected to provide 6 billion kWh of clean energy annually. It is intended to support offshore wind development in China and contribute to the country’s dual-carbon goals.
The topside consists of a seven-floor steel structure covering 7.000 m² and reaching 43 m in height. It is designed for installation on a 75 m high offshore jacket weighing 13.600 tonnes.
The weighing operation was carried out under restricted installation conditions. The equipment had to be installed on 1 m high skidding tracks, with only 680 mm of available installation space. Support piers on both sides of the tracks prevented large machinery from entering the work area.
Sinotrans Sarens distributed the weighing equipment across multiple positions along the skidding tracks. The system comprised 230 strand jacks, 230 load cells, 32 displacement sensors and six pump stations. Equipment weighing up to 450 kg had to be installed manually.
A synchronous closed-loop control system was used to manage load distribution, monitor the weighing process in real time and make adjustments during the operation.
Installation of the complete weighing system took 10 days and was carried out between ongoing construction activities at the site. Joint debugging and calibration required a further half day before the weighing operation was completed.