The invention provides a rolling technology and a heat treatment method of pre-hardening type plastic die steel.LGP20 series, LG718 series and LG2311 series
steel plates with stock thicknesses of 220 mm are subjected to the rolling technology and heat treatment.A technological process comprises the following steps: plate blank heating, rough scale removal, rough rolling, finish rolling, straightening, cooling after rolling, nibbling shear, stack cooling, flaw detection, steel plate examination, marking, shot blasting, normalizing, stack cooling, shot blasting,
tempering, surface checking and performance judging.The rolling technology and the heat treatment method of the pre-hardening type plastic die steel have the advantages that an optimal heating technology is determined, and influence of
casting blank segregation to steel segregation is reduced; by normalizing and
tempering technologies, a structure form similar to thermal refining is obtained, and the problem that a plastic die steel plate is easy to crack in a
quenching process is avoided; through large-rolling-reduction rough rolling, compactness of the structure of a steel plate is improved, and internal shrinkage of the steel plate is reduced; cooling is controlled reasonably after rolling and normalizing, the ideal structure is obtained, and
cracking of the steel plate is avoided; and
weather factors are overcome, and goods can be produced and supplied all the year round.