Why do SEAL laminators have crowned rollers?
To overcome the “bending” effect of the top roller. When a roller is pulled or pushed down by its ends it will take on a ‘banana’ shape. This effect increases equal to the amount of pressure you put on the roller. This effect can be overcome by either using some very expensive, big diameter rollers, which would make the laminator twice as expensive, or using rollers which are slightly bigger in diameter in the middle (crowned). This way the pressure (and thus the speed) is the same in the entire nip, which is crucial for wave-free laminating.
