Yes you can, for the same reasons you might use a single spreader and with the same application limitations. For example, you could put two bowed rollers together. As we discussed in great detail in my Web101 class, geometries for this are super fussy. Also, as we discussed, the devices can be configured to run in either the dual bow or tandem bowed roller modes. Another device we talked about is the dual bowed pipe spreader that Beloit trademarked with the Pos-Z name. However, you are not limited to two of the same spreaders. You might put a bowed roller followed by edge pull spreaders as they are complimentary. The bowed roller tends to do better in the middle and the edge pull spreaders tend to do better on the edges, obviously. You are also not limited to two spreaders. On some very unusual applications, such as super extensible nonwovens, you could put as many as a dozen spreaders together with progressive bows to permanently widen webs. As such they are acting as a forming process, something like a tenter frame does on biax film. Still, let’s not get crazy here. Each element must be sized and applied appropriately as we discussed in our award winning and trademarked Web101 class. Also, no matter how many spreaders you use, you can’t push the web too far. Most are friction limited. All have trouble with narrow webs, possibly to the point of bi-stable path problems that could, in the extreme, run the web off the rollers. So the point of all of this is to know what you are doing because trial-and-error in the field can be expensive and can be discouraging if initial efforts are judged poorly by the web.
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