ALEXANDRIA, Va., Dec. 2 -- United States Patent no. 12,486,550, issued on Dec. 2.
"Differential heat treatment method for forming roller" was invented by Sang Seok Jeong (Dasan-myeon, South Korea).
According to the abstract* released by the U.S. Patent & Trademark Office: "The present disclosure includes a differential heat treatment method for a forming roller including an outer circumferential surface heat treatment step for heating the outer circumferential surfaces of roller units. The method may additionally include a first natural cooling step for naturally cooling until the surface temperature reaches 100-150deg C., an inner circumferential surface heat treatment step for heating the inner circumferential surfaces of the roller uni...