How to Control Web Tension in the Unwind Zone
Featured Product from Dover Flexo Electronics, Inc.
For an unwind zone (on a web press or converting machinery) under closed-loop tension control, tension can be controlled by a pneumatic brake, an electric brake or a regenerative drive.
During machine operation the measurement signal from the tension transducers is input to an automatic tension controller. The controller compares the actual tension to a desired tension set point input by the operator. The controller works by sending a compensated electric or pneumatic signal output to the control device.
The output signal decreases as the material roll decreases in diameter to maintain constant tension going into the next tension zone.
Trying to Simplify Web Tension Control?
Can we reliably control a process variable like web tension without measuring it? Even with a forgiving web process, it's not likely we could consistently maintain accuracy and repeatability. To directly control tension we need to be able to monitor the tension we're actually running at so that our control system-whether human or electronic-can make machine adjustments to get us to where we want to be.
The simplest way to determine the running tension on your web in any isolated zone of your web press or machine is to install an idler roll that also measures tension. The most reliable dead-shaft idler roll with accurate tension-sensing capability is the original: the TR Tension Roll transducer.
Watch>>> Tension Roll Video
DFE is the natural choice of process and maintenance engineers for upgrading existing machinery with modern, efficient tension control. OEMs and machinery builders choose DFE to incorporate the most reliable, cost-effective tension controls into their machine designs. Consistent quality, product reliability and superior technical support translate into low cost of ownership for all our customers.
Are you measuring process tension on web or flexible substrate?
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Our products are used in unwind, rewind, and intermediate applications for any moving continuous material which undergoes an operation such as printing, coating, laminating, treating, metallizing, rewinding, unwinding, slitting, coating or other processes. Tension measurement and control systems for flexible packaging and paper, film and foil converting are our specialty.
We have over 84,000 tension transducers installed in manufacturing facilities everywhere. DFE transducers (sometimes referred to as 'load cells') are the industry standard for direct tension sensing and measurement. We are a recognized leader in tension technology.