Those machines are referred to as slitters. I designed and built 2 for 3M Abrasive division back in the 1990’s. Talk about a process that involves less than reliable hardware, (I never met an air bar or pneumatic web sensor I didn’t hate), and enough wishful thinking to achieve the speeds 3M wanted them to run at that would make an Alchemist proud. I was constantly amazed that my designs even worked at all.