Roll Forming Vs. Stamping: Differences and Advantages
We have found that oftentimes, current and potential clients in need of metal fabrication want to know the difference between roll forming and other processes and which is best for them. Many wonder if processes such as stamping, brake forming, or extrusion are the right choice, and how they differ from roll forming.
Roll forming versus stamping, for instance, presents a number of differences, as well as certain distinct advantages. We will identify the differences between roll forming versus stamping by going over some common fabrication factors considered in both: length, labor, material, and fabrication processes.
The length of a part is one of the most important factors when trying to decide between roll forming and stamping. In most cases, stamping parts longer than 10 inches will have more expensive tooling. A 36” to 48” stamped part may be double or more what roll forming dies would cost. Roll forming tooling, on the other hand, has no restriction on length other than the size of the facility producing the part and the weight-handling capabilities there.
Stamping will get even more expensive if there are multiple lengths of the same profile. To produce parts at multiple lengths, completely separate multiple stamping dies would be required. The more lengths you add, the greater the stamping die cost. With roll forming, no additional tooling is usually required. A simple adjustment can be made on all roll forming machines to produce parts of different lengths, typically using a digitally-controlled computer.
Another operation cost is labor. One way stampers attempt to create longer parts is through secondary assembly. Secondary assembly does reduce the tooling costs, but it increases the labor costs to join the two parts together. As we already learned, roll forming can adjust part lengths on the machine on the fly, which is much less labor intensive. Stamping short parts is also more labor intensive when including holes, trimming, or complex notching and multiple stamping press stations that may be required then. Most stamping dies don’t include advanced fabrication options, so a secondary operation is required, which can be conveyorized and automated, also at extra expense and setup cost. With roll forming, many advanced fabrications, such as holes, trimming, or notching, can all be done inline, reducing secondary fabrication costs, though additional fabrication conveyorizing can also be done in roll forming. There are also many ways to post fabricate roll formed parts automatically in conveyorized stations as we do at Johnson Bros. For example, as a reduction of allowed end flare, roll forming can produce that; stamping and brake forming do not.
The metal options between stamping and roll forming are very different. Both can handle light-strength steel, such as carbon steel, but when it comes to working with high-strength steels, roll forming has the upper hand. High-strength steels are very difficult to stamp because of springback, galling, and scratching. The harder the steel, the more likely the steel will bounce back to its original shape after stamping. Even if stamping is successful in forming high-strength steel, there will be evidence of galling and scratching on the finished shape. In roll forming, there is a gradual bend as steel moves through each bending pass. This gradual bend reduces springback, galling, and scratching when high-strength steel is used.
For the right applications, roll forming has many advantages over stamping. Roll forming can offer the lowest tooling and maintenance costs with the assurance of quality metal fabrication.
Now that we are in the new facility, which doubles our size, stampings will also be offered at Johnson Bros. (with some already produced!).