Production method for rolling flaw-detection-guaranteed steel ingot into ultra-wide chromium-molybdenum steel plate

The invention discloses a production method for rolling flaw-detection-guaranteed steel ingots into ultra-wide chromium-molybdenum steel plates. The production method comprises the procedures of steel ingot high-temperature annealing, cogging, heating, rolling and slow cooling. Wherein the rolling process adopts a rough rolling and finish rolling composite rolling process; in the rough rolling stage, the blank is sent to a rough rolling machine after being discharged out of a continuous furnace, and the initial rolling temperature is higher than 1100 DEG C; in the finish rolling stage, the rolling rough width is 3700-3800 mm, the pass rolling reduction is guaranteed to be larger than or equal to 25 mm during rolling, and the rolling reduction of the first pass to the third pass is guaranteed to be larger than or equal to 30 mm; the rolling rough width is 3800-4050 mm, the pass rolling reduction is guaranteed to be larger than or equal to 20 mm during rolling, and the rolling reduction of the first pass to the