Process description 

In forming process of direct square molding producing square pipes,rectangular pipe, adopt combined roller, slice structure, with roll mat filling between roller slices, and a set of roll can cover many pipes, roll utility rate *0%. Roller adopts slice structure, in the deformation area, roll contacts with strip locally, not fully, which reduce contact area, less friction between strip and roll, reduce roll consumption and energy consumption of units forming accordingly. 

Production of round pipes adopts ZTF molding process, including rolls of openings molding segment can adapt to forming requirements of various specifications of steel pipes, the openings molding area basically doesn't need to change rolls, roll utility rate over *5%. Level roll is improved by traditional large circular arc contact to three-point contact, also reduce the roll consumption of friction and consumption of force. At the same time, molding vertical roll groups participation deformation, adopted three-point round principles and specific curve adjustable rotating vertical roll, can make the pipe billet molding reach best stress state, which reduced the roll volume, reduce roll weight, also reduced friction between trip and roll, reduce roll consumption and energy consumption of units forming accordingly, compared with the traditional vertical roll structure.