Drum Regulation

A stiff speed regulator in the drums can provide a multitude of benefits.

Diagnostic: A stiff drum regulator can isolate control problems to pre-drum regulation or post-drum regulation. Pre-drum regulation refers to the unwind, guide or lead-in roll, any paper rolls or bowed rolls. Post-drum regulation refers to the rear drum, front drum and rider roll.

The optimal way to stiffen the drum control is to implement a type III control system for the drums. For the typical 1 or 2 drum winder, this means that a regulator with two integrations should be used for the rear drum. This approach has several advantages both with regulation and auxiliary functions. With regard to regulation, the type III system tends to counter some of the prevalent resonance’s in the drums, and secondly allows a greater accuracy on predictive automatic stop-to diameter and length.

In addition, the stiff rewind regulator helps identify unwind and paper-transport problems. Since the rewind is less reactive to the transients from the unwind and guiding sections, problems in tracking and tension can more readily be isolated to the unwind or guide/lead-in rolls. This helps the control engineers troubleshoot any problems and make corrective actions. These are normally done during the equipment startup.