February, 2025- Q: What are some considerations when purchasing a plate roll machine?
A: Whether you’re new to plate rolling or an experienced manufacturer needing to upgrade it’s wise to begin the process with discussions involving type of material, thickness range, maximum width and the profile/diameters to produce. It is also important to review what will happen to a part after the forming process, which helps make more well-informed decisions on plate roll purchases.
Q: What are the key differences between a three- and four-roll plate roll?
A: A four-roll plate roll provides the quickest and most accurate bends, but it lacks the operating range that typically comes with a three-roll machine. The most common type of three-roll machine would be the double pinch variant, which is typically cost effective and easy to operate. Double pinch machines allow for pre-bending of both plate edges in a single pass without the need for removing and repositioning the material multiple times. They also work with a wider range of plate thicknesses and shapes due to the large gap between the top and bottom rolls.
In comparison, three-roll initial pinch machines use the rolls in a different orientation and are usually used for lighter-duty applications because the operator must physically remove and turn the material around to pre-bend both ends of the plate. For heavier jobs, three-roll variable geometry machines shine because they are able to form the widest range of material types and thicknesses in relation to the size of the top roll, which moves vertically while the lateral rolls move horizontally. This configuration effectively allows the machine to operate like a V die on a brake, meaning less force is required to form material when the lateral rolls are moved further apart.
A four-roll plate roll uses the fourth roller (or the pinch roll) underneath the top stationary roll to hold the plate firmly in place during the forming process, which also eliminates the need to remove the material and reorientate to achieve the pre-bend on both sides of the plate. Their unique material clamping capabilities oer two key advantages: better accuracy and minimized at spots in the material. Four-rolls shine in large-scale production environments and during complex bending tasks.
Q: What factors should be considered when looking at CNC versus NC controlled plate rolls?
A: NC plate rolls give operators reference points that they can use to gauge how the material is reacting at certain points during the forming process. Skilled operators can track these and build a database of roll position knowledge to achieve various radii and proles with many different material types and thicknesses.
With CNC plate rolls, it’s important to understand that while most CNC machines can store rolling jobs and recipes that can be recalled for quick repeatability, there still needs to be a skilled operator with the understanding of the forming process present to build the CNC program. Only in the last few years have manufacturers begun unveiling new CNC technologies that consider dimensions, properties and desired results.
With labor dependency becoming a greater obstacle day after day, it’s now becoming imperative for some companies to consider these new CNC-controlled rolls to minimize downtime caused by the absence of a skilled operator. While traditional NC three- and four-roll machines still exist for companies that have the knowledge on how to operate them effectively, the adoption of CNC machines that do most of the heavy lifting on the calculations side help pull back the veil on the art of traditional plate rolling.
Q: How will plate roll technology continue to develop?
A: The ever-increasing need for skilled labor is causing companies and manufacturers alike to invest more and more in CNC controlled machines and automation—and CNC plate rolls that rely less on operator ability are becoming a requirement. Fabrication Solutions & Technologies is already working with plate rolls that have closed-loop bending systems that automatically measure the radius of the rolled material during each pass of the forming process and self-adjust for discrepancies in material properties. As this technology continues to advance, outside of forming conical parts, the labor dependency of having a skilled plate roll operator will continue to decrease.
RYAN MCKELVEY works in technical sales for Fabrication Solutions & Technologies, Longview, Texas, fststeelfab.com.
