Abstract:
Almost every web handling or converting process starts or ends with a roll of web, yet the quality of the web at unwinding is rarely as good as it was going in to the roll at winding. Winding-related waste comes in many categories, including bad core starts and wrinkling, misaligned layers and telescoping, slipping and scratching, hard bands and bagginess from crossweb thickness variations, or buckling in either machine or crossweb directions. Understanding the root causes of these defects and their common remedies can quickly improve your profitability.
The goal of this workshop is to show how to improve your roll and web quality through a better understanding of the winding process, winder design, and roll measurements.
Unlike any other option in web handling education, the AIMCAL series of web handling ?workshops? are one-of-a-kind training that combines classroom seminars with on-machine demonstrations.

Who will benefit from this workshop?
This workshop is directed towards technical employees of any level with a need to understand the fundamentals of winding, winders, and roll defects. Though the seminar will include some engineering theory and equations, the workshop?s goal is to show how theory and experiment lead to practical solutions to common problems.

Seminar Outline
The three-day workshop will aim for a 50-50 split between seminar and lab demonstration time. Seminar topics will include all the background needed to understand the lab demonstrations and more, including:

• Why wind rolls and how should rolls be wound?


• Web and roll defects from winding


• Wound roll hardness: experimental and analytical assessment


• Winding methods: center winding, surface winding, center winding with nip


• Wound roll storage effects


• Wound roll unwinding

Lab Demonstrations

Lab #1 - Measuring Internal Roll Pressure
See the most common methods to determine the pressure within a wound roll, including pressure-sensitive paper, pressure-resistive sensors, frictional slip sheets, and stepped punch-out friction measurements.

Lab #2 - Cinching and Telescoping
See how winding and unwinding conditions can lead to cinching (machine direction slippage between roll layers) and telescoping. Learn simple techniques to measure roll sidewall alignment.

Lab #3 - Measuring Roller Hardness
Measure crossweb roll hardness variations and compare them to crossweb thickness variations and web bagginess. 

Lab #4 - Stack Modulus Testing
See the lab equipment required to measure stack modulus (or radial modulus), one of the most important properties to understand how your product reacts to the winding process. Learn how to estimate your stack modulus from internal pressure measurements.

Lab #5 - Air Lubrication at Winding and Nips

See how air lubrication and shifted layers are prevented with a winding nip. Measure the hardness or tightness difference in a roll wound with and without a winding nip load.

For more information, click here.