Production method of ultra-thick steel plate with ensured transverse impact toughness

A production method of an ultra-thick steel plate with ensured transverse impact toughness belongs to the technical field of low-carbon structural steel controlled rolling. The process comprises the following steps of: a smelting process, a continuous casting process, a heating process, a rolling process, a normalizing process, and the like. The advantages are that: different from traditional controlled rolling controlled cooling processes, the technology, which is used to design a casting blank type, can increase the transverse mechanical properties of steel plates; meanwhile, the temperature-waiting thickness is larger than that of a finished product by only 20 mm; the steel plate is not cooled by water after rolling by a finishing mill; the production process is simple, and the cost is low.