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Web Handling & Converting

Blogmaster: Dr. David Roisum

17
Ever got a returned roll from a customer?  Looks nothing like when it left the winder.  Looks truly beat up.  Who dunnit?  Handling by your people, trucking/rail, your customer and what was the offending element?  Simple, put a roll handling tattle-tail in the core.  Th...

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15
Semi-Intelligent and Truly Intelligent (Forklift) Clamps
There are truly stupid clamps that have only two settings:  open and closed.  The closed pressure is set conservatively so that no load ever gets dropped even if that means crushing the small roll or box.  Semi-intelligent clamps use lookup tables to set clamp pressures based on lift ...

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Posted in: Winding
11
There are tens of thousands of Europeans who should be familiar with web-handling because they design, operate or service web equipment.  Some of you may not have heard that in addition to a Web-Handling Technical Conference, June 13-15 in Prague, there are three shortcourses in must-know areas...

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10
A continuation of previous post.  After you have done everything appropriate and possible by either increasing (Type III) or decreasing (Types I and II) all of the winder TNT’s, the problem is no longer a winding problem in the sense that there is no winding solution.  We must consid...

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Posted in: Winding
08
Core Crush – Three Defects for the Price of One
Core crush is not one defect, but three totally different defects that share the same name (and final outcome). Core Crush Type I – Here the loads that cause the core to give way come from winding (tensions converted to) pressures.  Here, the core fails during or shortly after winding.&n...

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Posted in: Winding
03
Q: A colleague of mine recently stated that use of a lay-on or rider roller that is not as wide as the web is 'common practice'. He sees this as a form of 'winding optimization', whereas the word that I would use is more like 'accommodation'.  We are winding a delicate .001" thick film that is ...

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01
I was wondering if you had any suggestions or advice with regard to a ___ condition that gets worse as we increase line speed. A clear increase in 'air-like' troubles with speed is the fingerprint of air entrainment.  Very little else is needed to independently verify that root cause. ...

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26
Load Cell Roller Wrap Angle
The load cell manufacturer can not make general recommendations for wrap angle.  The value for minimum wrap angle depends on all of the things needed for sizing (selecting maximum capacity) a load cell such as tension, width, roller and fixture tare weights and so on, all of which can not be kn...

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24
Wrap Angle Rock Around the Clock
At uber, ultra, very, big, great risk of over-generalizing and over-simplifying, I would like to offer you some ideas on some application range for wrap angles.  The application ranges include idlers, tendency and driven rollers and include systems that are and are not wrinkle-prone.  Here...

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20
Profile and Winding Tightness
The winder TNT settings plus material properties determines the AVERAGE winding tightness across the width.  Profile variation determines how the tightness is distributed.  Seldom in the real world can we vary average winding tightness by much more than 2:1, even if we throw all of the kno...

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Blogmaster

David Roisum photo

Dr. David Roisum

Dr. Roisum is a well-known authority in the area of web handling and converting. He has authored seven books, including Winding, Rollers and Web-Handling and has coauthored or edited several others. He was a technical editor for Converting Magazine with a monthly column entitled "Web Works." An accomplished professional speaker and instructor, Roisum has been praised for his skill at translating highly technical information into a common sense practical reference. Dave has been honored by TAPPI with their Finishing & Converting Division Award, Thomas W. Busch Prize and Finest Faculty awards and is a TAPPI Fellow. Dave received his Ph.D. from the Web Handling Research Center where he later became an Industrial Advisory Board member.

Dave has worked for the Beloit Corporation as a designer of winding machinery and later as a manager of research, and for Kimberly-Clark as a converting expert serving all business units. He is now a principal of Finishing Technologies Inc., providing consulting services to more than 300 clients who convert or manufacture: paper, film, foil, nonwovens, textiles and many other materials. He has accumulated much practical experience working in nearly 1,000 plants over the course of more than three decades.