The 8.61-meter diameter shield machine main bearing made of steel produced by Daye Special Steel Co., Ltd. successfully rolled off the production line in Changsha, which created the world's three largest diameters of integral shield machine main bearing, single weight and load-bearing weight.
The main bearing off the line can be used to drive 18 meters large diameter shield machine, the product weighs 62 tons, stands up to 3 stories high, and can withstand more than 10,000 tons of load. Its successful development marks the development and industrialization capacity of domestic large diameter main bearings among the world's leading level, which means that the main bearings of the shield machine have been fully localized, and the full coverage of the main bearings of the domestic shield machine from small and medium diameters to large diameters has been achieved.
The main bearing is the "heart" of the shield machine, and in the advance of cutting the road and crossing the river and sea, the shield machine relies on it to drive the cutter head to keep rotating and advancing. It needs to face the shield machine ultra-heavy load, large biased load, frequency variable load and other extremely harsh conditions test, and because it can not be replaced in the tunnel, its material, design, manufacturing and testing requirements are extremely high, in the top of the large-scale high-end precision bearing industry chain, the development difficulty is doubled with the size increase.
In order to open up the "last link" of the whole industrial chain of shield machine, Daye Special Steel has devoted itself to the study of harmful element control, trace element control, non-metallic inclusion control, and microstructure uniformity control in main bearing steel. With international advanced production equipment and technology, Daye Special Steel has produced high-performance and long-life bearing steel, which has passed the user's complex and rigorous working condition simulation test. It is applied to multi-specification main bearings and provides guarantee for the domestic shield machine to have a full series of Chinese "heart".
