METHOD FOR SCREW ROLLING OF FINNED TUBES AND ROLLS FOR PERFORMING THE SAME Russian patent published in 2005 - IPC

FIELD: plastic working of metals, namely processes for making finned tubes by cross screw rolling, possibly in three-roll mills.

SUBSTANCE: method comprises steps of continuous deforming of blank metal in gages of three rolls arranged uniformly and turned relative to rolling axis; drawing fins of tube due to axial reduction of metal in gages; shaping fins and finally sizing them in gages of cylindrical portion. Fins are shaped due to axial reduction by means of pairs of working gages having similar profile and gradually increased thickness along outer diameter (said gages are placed on one roll) also by means of pairs of intermediate gages arranged opposite relative to working gages on two other rolls and having profile corresponding to that of working gages but less outer diameter. Fins are sized at preventing possibility for damaging shaped fin. Rolls are in the form of set of variable-profile discs; discs are mounted on the same axis and form gages. On cylindrical portion of rolls pairs of working gages and pairs of intermediate gages are mounted at minimum shift along rolling axis. Pairs of intermediate gages are mounted on two rolls opposite relative to pair of working rolls. Shift pitch and diameters of gages are normalized.

EFFECT: enlarged manufacturing possibilities of equipment and tool; enhanced quality of surface of ready shapes, uniform working of metal structure and metal deformation at shaping fins, lowered minimum diameter of reducing shapes, increased surface area of outer surface of fining.

2 cl, 3 dwg, 1 tbl, 1 ex