R & B Constant Tension Unit
The Constant Tension Unit will control output tension to a value adjustable by the operator. A pneumatic cylinder connected to a moveable roll is used to induce tension in the web. The pressure in the cylinder is proportional to the web tension.
A nip point is created between a driven roll and a rubber coated nip roll. This nip point isolates the input tension from the output tension. A displacement sensor on the moveable roll creates a speed error signal.
Any movement on this roll indicates a tension upset. If a tension upset is sensed the motor speed is adjusted to keep the moveable roll centered. This produces a constant tension on the output regardless of tension changes on the input side.
Custom widths and tension ranges are available.