Tension Control for Narrow Web Applications

Dover Flexo Electronics is an OEM supplier of Tension Roll® Transducers, Narrow Web Transducers and Model C Series Transducers for Mark Andy, Nilpeter, HP and other leading flexographic and digital web printing press manufacturers.  Our products, backed by an industry-leading 5 Year Warranty, have earned the trust of press builders and system integrators all over the world.  In addition to supplying new press manufacturers, we have many decades of experience upgrading older presses with turn-key tension control systems or component packages designed to integrate with a PLC.

High-Performance Load Cells
Narrow Web Transducers feature precision-balanced load cells fixed internally at each end of the idler roll that provide highly accurate tension measurement. The dead shaft core and distributed load cell deflection of the design delivers exceptional web tracking performance.

By summing the dual load cell outputs together, tension can be measured accurately regardless of the web position on the roll face. Alternatively, in combination with a TriView LRT tension indicator, the NW transducer can report web edge tension characteristics, if needed.

The Narrow Web transducer is available in three roll diameters: 2.25″ (57 mm), 3″ (76 mm) and 3.5″ (89 mm) and in standard lengths up to 20″. An optional LED display indicator mounted in the end of the roll is available on 3.5″ diameter Narrow Web transducers 8″ or longer in length.
VNW Tension Transducers are cantilever-mounted on process machinery for unwind (payoff), rewind (take-up) or intermediate zone applications. Tension is measured by high-output semiconductor strain gauges housed internally on a dual cantilevered transducer beam and connected in a wheatstone bridge configuration. As the ribbon or filament passes over the rotating transport wheel, the force of the substrate on the wheel shaft causes a minute deflection of the transducer beam. The resulting change in strain gauge resistance yields a voltage output from the transducer that is proportional to tension. The transducer output is then amplified by a DFE indicator or automatic tension controller for tension measurement or complete closed-loop tension control.
Powerful, Easy-To-Use Closed-Loop Tension Controllers
The SteadyWeb™ 6 Digital Tension Controller maintains a pre-selected tension set point on a web machine or press by measuring web tension from a tension transducer (or transducer pair), and then sending a compensating signal to a tensioning device such as a pneumatic brake, clutch or a DC drive. The digital closed-loop PID control algorithm allows manufacturers to improve process consistency and productivity.

The large, bright and colorful touchscreen user interface is so easy-to-use that your operators will be up to speed with minimal instruction and training time. Initial setup and configuration is fast with illustrated prompts and color graphics.

The controller may be used in unwind, rewind or intermediate tension zones. A variety of controller output modes are available for operating pneumatic or electric brakes and clutches, eddy current clutches, and DC and AC drives.
Right-Sized, Precision Manufactured Brakes
As an integral part of a high-performance unwind package, the 60 Series Brake delivers the appropriate torque level needed for a particular application by allocating actuation of the appropriate number of cylinders, from one up to six. The term ’60 Series’ is derived from ‘6’ – the brake diameter in inches, and our use of a second digit to signify the number of cylinders that are installed on the brake.

The 60 Series brake is the ideal low-cost pneumatic brake for low torque applications and for unwind stations on smaller presses and converting machinery.

To see if a brake in the 60 Series is the right size for your application please note its torque range listed below and review the 60 Series Brake section of DFE’s full Brake Catalog for detailed sizing information, options and accessories.
The Benefits of Upgrading Your Narrow Web Tension Control
When tension is properly controlled, waste and down-time are kept in check by solving registration problems that affect printing, laminating, die cutting and inspection processes. Proper tension control can also prevent web breaks, stretching, coating inconsistency and other process defects. Closed-loop tension control systems can also enable increased print speeds and broaden the range of applications that can be run on a single press.

Turn-key web printing press tension control systems typically incorporate:
• A closed-loop tension controller such as the SteadyWeb™ 6
• A load cell such as the Tension Roll® Transducer, Narrow Web Transducer or Model C Series Tension Transducers
• A Pneumatic Brake, Electric Brake, Clutch or an electric output to a Motor Drive System

Web printing press component upgrades (used with a PLC) often incorporate:
• A load cell signal amplifier such as the TA1 TrueTension™ amplifier
• A load cell such as the Tension Roll® Transducer, Narrow Web Transducer or a pair of Model C Series Transducers

Trusted Installer Network
DFE’s turn-key tension control systems are designed to be easy to install by an end user. However, some customers may prefer to work with a systems integrator that can provide on-site support and manage the upgrade process from start to finish. For this reason, we maintain a network of trusted installers throughout the country that can assess customers’ individual needs and provide the personal attention necessary to guarantee a successful outcome.