The first batch of 690 MPa high-performance bridge steel Q690qENH has been sent to users for the construction of Wuhan Jianghan Seventh Bridge. At present, the construction of the Wuhan Jianghan Seven Bridge with a main span of 408 meters has experienced the test of the epidemic situation, and has entered the stage of the main span beam. This is also the first time that the world's leading domestic 690 MPa high-performance bridge steel has been applied to the construction of large-span bridges in China.
The seventh-generation high-performance bridge steel Q690qENH is hailed as "the crown jewel" of Chinese bridge steel. Compared with the sixth-generation bridge steel, the seventh-generation high-performance bridge steel produced by Baosteel Co., Ltd. has significantly increased its yield strength level from 500 MPa to 690 MPa. Its key technical indicators such as yield ratio, weldability, and low-temperature toughness are higher than International standards.
In recent years, with the continuous improvement of navigation requirements and the influence of various complex factors such as hydrological conditions, flood control and water conservancy projects, and the use of shoreline terminals, newly built bridges on major rivers such as the Yangtze River are moving towards the middle of the river and there are no more pier The direction of the pier. With the iterative development of domestic bridge steel technology, the record of the bridge's largest main span will be continuously refreshed, and the era of "one span across the river" is accelerating. Jianghan Seven Bridge is the seventh large-span urban heavy-load bridge across the river planned and constructed in Wuhan. According to the design, the Jianghan Seventh Bridge will not erect piers in the middle of the river. The successful development of 690 MPa high-performance bridge steel will greatly increase the length of the main span of the bridge, which is the basic material guarantee for the Jianghan Seventh Bridge to achieve "one span across the river".
Q690qENH bridge steel has many special requirements in terms of mechanical properties, production processes, welding performance, etc., which poses great challenges to the company's R & D, production, quality and other capabilities, and is difficult to research and produce. In more than two years of continuous research, Baosteel's heavy plate production, sales and research team has worked closely with collaboration units to coordinate research on user needs. Not only has it successfully developed 690 MPa high-performance bridge steel, but also related welding materials and Welding process has also achieved independent innovation, and has declared 7 national invention patents.
In the next stage, Baosteel will closely track the manufacturing and installation of steel beams by users, timely resolve new situations that arise during use, and constantly improve relevant manufacturing processes and quality control. At the same time, it will introduce 690 MPa grade bridge steel to key customers at home and abroad, and strive to obtain application in more major bridge projects at home and abroad.
Source:China Baowu Group
