Spraying method for pack rolled sheet parting agent

The invention discloses a spraying method for a pack rolled sheet parting agent. The spraying method includes the steps that after a blank to be subjected to pack rolling is subjected to cogging to reach the size of 60 mm to 80 mm, the thickness of a lower blank which is milled after sizing is larger than that of an upper blank by 1 mm to 2 mm; then ring groove forming, plane milling and fillet expanding are conducted on the lower blank, and therefore a parting agent spraying groove is machined; after machining is completed, the mixed parting agent is sprayed into the parting agent spraying groove, and the whole spraying groove is filled with the thickness of the parting agent; then the lower blank obtained after the parting agent is sprayed is conveyed into a baking oven to be dried, thebaking temperature is 450 DEG C to 650 DEG C, and the baking time is 50 min to 75 min; and finally, after the parting agent is dried, the lower blank is taken out of the baking oven, the lower blank is cooled to be below 100