Roll Forming Vs. Press Brake Forming

Q: I am considering using a press brake for component parts.  Is there a way to determine if another method, such as roll forming, could deliver better results?

A.  Making parts on a press brake in small quantities is a cost-effective process. However, roll forming costs less when making  large quantities over a long period of time.  The good and bad parts of these processes are listed below:

• Press brake forming generally requires more test blanks – scrap – and if the part is complex and precisely cut, it may be too intricate to bend or manufacture on a press brake.
• Press brake forming is regarded as an “art,” resulting in varying levels of quality, 0ut-of-tolerance parts are salvaged or scrapped. Metal roll forming produces more consistent level of accuracy.
• The bend angles attempted with press brake forming are dependent on the material variation, its springback properties, and the friction between the die and the blank during forming. In metal forming, the material is progressively bent and it’s in contact with the forming rolls for a longer time. The shape is reinforced by this lengthened contact, eliminating springback and making metal forming less affected by material variation.
• Set-up for a press brake is usually less,  but the roll formed piece-per-hour production rate is greater, since the manufactured parts come from a continuous coil, eliminating the need for part loading.
• With press brake forming, the part length can’t be any longer than the width of the brake press die. Metal roll forming can be any length required.
• Depending on the shape of the part, metal roll forming can be performed  in one operation, where using a press brake can require more than one hit.
• Holes and cut-outs can be manufactured with an inline pre-notch and/or cut-off operation, reducing the number of operations required and reducing cost and overall production time.
• A single bend is accomplished easily with roll forming or press brake. The advantage of metal roll forming is that it can produce multiple precision bends over thousands of feet of material, quickly and efficiently.

Please view metal stamping and extruded aluminum for additional samples.