METHOD FOR ROLLING ROUND CROSS SECTION SHAPES Russian patent published in 2001 - IPC

FIELD: rolled stock production, namely manufacture of round blanks. SUBSTANCE: method is realized by means of calibration system "rectangular-square- circle" while using round universal final roll grooved pass. At first rolling is performed in double-roll box-type pass and in universal four-roll square pass. Rolling in universal roll passes provides next advantages: uniform deformation of metal along width of shape, good descaling of lateral surface of rolled piece; stable position of rolled piece on roller table at transferring it from pass to pass and so on. At initial stage rectangular blank is rolled in open box-type and in universal square four-roll passes in order to receive square rolled piece. Final rolling is realized in round universal four-roll grooved pass. Relation of square blank side to diameter of round pass is a/D=0,9-0,92. Method provides manufacture of shape with stable surface curvature in its cross section. EFFECT: enhanced quality of structure of round blank surface, stability of technological process, increased efficiency of rolling process. 1 dwg, 1 tbl, 1 ex