The hydraulic systems Changjiang Hydraulic has developed are mainly to serve some national key projects, like railway construction and ship building. For example, the 400t/500t hydraulic grab system designed by our company was applied in the Three Gorges Dam Project; our DYY300 hydraulic platform lifting system was used in the Shanghai Maglev Train; the aspire tower and the hydraulic stage lifting system was applied in the opening and closing ceremony of Beijing 2008 Olympic and 2008 Summer Paralympics. These programs have won the Sichuan Science and Technology Progress Award, the Industry outstanding new product award, and the National Defense Science and Technology Commission awards for several times.
This hydraulic system is designed in the Three Gorges Dam to realize a connection and disengagement of the door. Since it is required to work 120~175m underwater, the hydraulic system puts forward high requirements in water sealing, corrosion prevention, and reliability, the performance of these is powerfully supported by displacement sensing and deep water anti-seepage techniques. Its upper system works to monitor the underwater shift system in real time.
This system is consisted of 4 hydraulic cylinders, with each cylinder incorporating independently controlled oil channel. It works basing on the synchronization technology, which allows the 4 cylinders to move synchronously. When their movement differs too much, the system will stop the cylinders and then adjust them to the same position. With staff gauge on the hydraulic cylinder, operators will have access to monitor the movement of cylinders at any time.
DYY300 hydraulic platform lifting system is especially used for track beam in rail transport. The unique synchronization technique allows the error to be less than 5mm when the platform rises to 11m away from the ground. The error of 2 platforms which are 25m away from each other is limited to 25mm, ensuring that the track beam is always kept horizontal in the process of lifting. In this way, the hydraulic system lifts 30m-long 180t concrete beam to the bridge pier when it is 8m-10m away from the ground.
This lifting system is designed with closed-loop proportional servo control to achieve a high-precision position control for hydraulic cylinder and a stepless speed control, ensuring the stability and reliability of the platform. The cleanliness grade reaches NAS7. The adoption of integrated proportional cartridge valve helps to meet the flow and speed requirements.
The hydraulic system used in the Aspire Tower in Beijing 2008 Olympic is designed to make the torch erected under the support of 2 main hydraulic cylinders and 2 auxiliary ones, and to fasten the torque with 8 plugs, guaranteeing that the torch stands at the edge of the Bird’s Nest stably and firmly.
This hydraulic system is consisted of 40 independent mechatronic units to switch the scene between 4 seasons. The plate is made to be like a book of 1440 pages, with 360 pages for each season. Each of the single pages is controlled independently. In the performance, the hydraulic system executes 12960 operations in total.