Grotnes rotary roll forming is a cold rolling process capable of forming profiled configurations to close tolerances in cylinders, conical shapes, hoops and rings. When producing parts of different diameters having the same profile, tooling costs and setup-times are minimized.
Blanks from tubing, pipe, or coiled and welded flat blanks are placed on the lower roll. Both the upper and lower roll starts rotating as the lower roll moves upwards. As soon as contact is made between the rolls and the blank, the required profile will be formed through several revolutions of the piece.
Near Net Shape rotary roll forming of circular parts is a precision process in which thick-walled rings are formed between dies that displace material both axially and redially to attain the desired shape. This process greatly reduces, and in many cases, completely eliminates machining.