Roll forming
From Wikipedia, the free encyclopedia
Roll-forming or Rollforming is a continuous bending operation in which a long strip of metal (typically coiled steel) is passed through consecutive sets of rolls, or stands, each performing only an incremental part of the bend, until the desired cross-section profile is obtained. Roll-forming is ideal for producing parts with long lengths or in large quantities.
[edit] Variation
A variety of cross-section profiles can be produced, but each profile requires a carefully crafted set of roll-tools. Design of the rolls starts with a flower pattern, which is the sequence of profile cross-sections, one for each stand of rolls. The roll contours are then derived from the profile contours. Because of the high cost of the roll sets, simulation is often used to validate the designed rolls and optimize the forming process to minimize the number of stands and material stresses in the final product. Rollforming machines are now being produed so that for similar products such as stud and track profiles, a new set of profile rolls is not required. This is achieved by the mill being split along its centre line and the web,flange and ear sizes are set using a contol panel which moves the mill rafts centrally to increase or decrease the aforementioned features.
Roll-forming lines can be set up with multiple configurations to punch and cut off parts in a continuous operation. For cutting a part to length, the lines can be set up to use a pre-cut die where a single blank runs through the roll mill, or a post-cut die where the profile is cutoff after the roll forming process. Features may be added in a hole, notch, embossment, or shear form by punching in a roll-forming line. These part features can be done in a pre-punch application (before roll-forming starts), in a mid-line punching application (in the middle of a roll-forming line/process) or a post punching application (after roll-forming is done). Some roll-forming lines incorporate only one of the above punch or cutoff applications others incorporate some or all of the applications in one line.
[edit] External links
- Inline Punching and Cutoff Press Applications in Roll Forming.
- Metal Building Panel-Ensure your rollforming operation is a good fit
- Rotary Punching Revisited for Roll Forming and Stand Alone appications
- High Speed Servo Rotary Punching Applications
- Notching and Piercing Tubes a Review of Tooling and Fabrication methods
- Analysis of roll formed tube.
- Quality Management in Rollform Design.
