This is designed for applications that need to wind wires or textiles, which means the right amount of tensile stress needs to be kept constant all the while the reel diameter is increasing. This is designed to pus pressure rollers against the yarn at uniform pressure. Even with plastic films and wires, the same requirements are present.
The HOERBIGER piezo-controlled proportional three-way pressure valves are ideal for these uses because of the accurate pressure and wide range of pressure control they provide. In addition, they use less energy and are highly stable. They have high control dynamics.