Refreshing method of aluminum profile combined porthole extrusion die

The invention provides a refreshing method of an aluminum profile combined porthole extrusion die and relates to a method for repairing and recovering a scrapped (invalid) aluminum profile extrusion die into a new aluminum profile extrusion die. The refreshing method comprises the following steps: processing an invalid lower die inner mold cavity into a round pit hole or a special-shaped pit hole with the depth of 20-30 mm by adopting an electric spark machine tool to form a lower die pit hole, preparing an insert with the same shape as the lower die pit hole, and scribing and drilling through a screw hole; putting a lower die body with the lower die pit hole into a box body electric furnace for heating, taking the lower die body out of the furnace, putting the big end of the insert into a counter bore of the lower die pit hole, pressing to the bottom of the lower die pit hole, processing the part of the insert, which is above a plane, by adopting the machine tool, then cutting a pass by using a linear cutting machine, extruding a lower die and finishing refreshing; and cutting an upper die tongue working belt of an invalid upper die tongue part into an upper die tongue surrounding part with the depth of 2 mm by using the machine tool or other equipment, welding the upper die tongue working belt, processing the upper die tongue working belt and precisely assembling an upper die and the lower die together to finish refreshing the aluminum profile combined porthole extrusion die.