The Coefficient of Winding Trouble
In winding, the important coefficient of friction (COF) is always about the two surfaces that will come in contact as the entering layer hits the winding...
The Great Span Length Debate | Part 2
Last month, we debated roller spacing (a.k.a. web span length) relative to cost, safety, out-of-plane deviations from gravity, bagginess, and misalignment. Let's continue the debate. ...
The Great Span Length Debate | Part 1
There are at least half a dozen things that come to mind in the great span length debate. Let's review the checklist to figure out what span length is right for you. ...
How Much Misalignment Is Trouble?
Shear wrinkles are the most common wrinkle mechanism, forming a diagonal crease and appearing to walk across rollers like an inch worm. The way to create...
How Much Misalignment Is Trouble?
Most converting equipment suppliers and manufacturers take care to ensure the rollers of their machines are aligned. Designing for good alignment, machining...
Who's Driving This Nip?
What is the best way to drive a set of nipped rollers? Two rollers and two drive options (driven or not) lead to four options. To make this discussion...
Shifty Answers to Nip-Induced Tracking
Nipping rollers are used in many value-adding processes in web converting roll coating, laminating, embossing, calendering, high-speed winding, and more....
Do You Have a Need for Speed?
Faster, faster, faster. As you reach the designed capacity of your existing process, before buying new equipment, most converters will ask if they simply...
A Wealth of Accumulators
A good accumulator should be like money in the bank easy to deposit and readily available to withdraw when you need it. A web accumulator is like a bank,...
Winding: What We Know & What We Don't Know
Winding is an amazingly complex process. Our understanding of winding can be broken into three areas: the winding process, winder design, and wound roll...
Idler Roller Bearings: Living the Good Long Life?
Most bearings are designed for a hard life, expecting to end up on a drive shaft of a high-speed motor with a heavy load. Some bearings, however, end...
The Spin on Idler Roller Testing
It's an election year, so I'd like to join the political pundits and offer some spin of my own, but my spin will be free of political opinions. Instead,...
Web Lines: Thinking About New Equipment?
A new year often brings new budgets and thoughts about new equipment. If you are lucky enough to be handed a project to buy new converting equipment,...
Differential Winding Limits: Part I
The purpose of differential winding is to apply a desired torque to two or more rolls winding on a single shaft. Differential winding allows multiple rolls to turn at differing speeds, with each roll free to slip at the speed required to compensate for roll-to-roll diameter variations and strand-to-strand length variations. ...
In Search of Tension Isolation
In web handling, one of the myths told most frequently is that of the independent tension zone, protected from other tension zones by the protective powers of the tension isolation. Like most myths, we want to believe, but alas, scientific reason is the myth buster....
Support Your Rollers: How should a roller be supported or attached to your equipment? | PFFC | September 2007
How should a roller be supported or attached to your equipment? To answer this question, let’s review your roller support needs and your options to meet these needs. ...
Baggy Webs: Part III—Causes
We know baggy webs are a problem and we know we can measure them. What do we do next? First, we need to find a way to fix it in the short term. Second, we can work on a long-term plan to prevent baggy webs from happening....
Folding Carton Shows Off
Adding a special effect to a package is one of the best ways to get a new brand noticed among dozens of similar products and thousands of other items on the retail shelf. One sure fire way to obtain a “look-at-me” look is via holographic technologies offering geometric, shimmering, and reflective metallic effects that provide the consumer with an almost interactive experience....
Don't Get Bent out of Shape
Bending a web is like bending a pencil or a wire. A little bending is no problem, but if you go too far, something will get bent out of shape or break....
Twist & Shout
A wrinkle is the web’s equivalent of a shout—stop it, you’re hurting me! To avoid your web shouting at you, think about how to apply uniform tension across it....
How to Drive a Winding Roll
What is the best way to drive a winding roll? You have three choices: from the surface, from the center, or both....
Dancer Rollers: Trust but verify
In last month’s tension quiz, I gave out five points if your process had a calibrated tension transducer roller. Those of you with dancer rollers might have wondered why you didn’t get any points. Why am I “dissing” dancers?...
Web Tension: A Pop Quiz
Today's column is a pop quiz on web tensioning. Feel free to work as a team on the answers. If you score poorly, don't worry, but it's worth your while...
Difficult Winding: Part II
Last month I introduced you to roll modulus ratio, the first of the terrible trifecta of difficult winding. This month let's move on to the next two of...
Whatever Floats Your Web
Why float a web? Because air floating can do things a roller can’t....
