Method for improving double bulges at edge part of broadened intermediate slab in thick plate rolling process

The invention discloses a method for improving double bulges at an edge part of a broadened intermediate slab in a thick plate rolling process. The method comprises the following steps: (1) steel rotates to enable the width direction of a plate blank to be accordant with the direction of a rolling center line; (2) the rolling broadening is performed in the width direction of the plate blank; and (3) the steel rotates to enable the length direction of the plate blank to be consistent with the rolling center line, and vertical rollers arranged at the two sides of the width direction of the plate blank are adopted to apply lateral pressure on the side edge of the plate blank to eliminate double bulges at the edge part; the steps (1-3) are repeated until the plate blank is broadened to a target width; and the steel rotation is performed again for the plate blank, so that the length direction of the plate blank is consistent with the direction of the rolling center line, and the fixed-width rolling is performed for the plate blank to reach the thickness of a finished product. The method for improving double bulges at the edge part of the broadened intermediate slab in the thick plate rolling process can eliminate the double-bulge deformation at the edge part of the steel plate, so that the plane shape of the steel plate is improved, the yield of the finished steel plate is improved, and the production quality of the finished steel plate is improved.