Method for reducing same plate difference of ultra-wide and thin specification high alloy steel plate

The invention discloses a method for reducing the same plate difference of ultra-wide and thin specification high alloy steel plates, and belongs to the technical field of ferrous metallurgy. A low-temperature long-time heating process is adopted when a blank is heated, and the blank passes through a descaling box for 3-5 times after being taken out of a heating furnace; a high-pressure water and high-pressure air combined descaling process is adopted in the rolling process, namely high-pressure water descaling is adopted for 1-3 passes after rolling and 1-3 passes before finish rolling, and high-pressure air descaling is adopted for other rolling passes; and a low-speed small-rolling-reduction rolling process is adopted for 3-6 passes before final rolling. Through innovative heating and rolling processes, the plate shape of the steel plate is effectively improved, the same plate difference of the steel plate is controlled within 0.4 mm, the surface quality of the steel plate is good, and the yield is as high