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8 Apr 15: Applications 14: The Magnetic Press

Bryan Creagan of KSH Consulting in Montreal, PQ is going to be occasionally contributing columns here.  This is his first one.  Welcome aboard, Bryan!

The concept is simple in that a magnetic field is introduced in one press roll to attract the opposing roll thereby forming a press nip.  In previous attempts, the field was huge to pull two large masses (cast press shells) together and the consequential power consumption figures were substantial.


In this day and age, electrical components have improved (downsized) and the masses can be greatly reduced.   Just think of two shoe presses opposite each other with a magnetic field pulling the shoes together.   Each shoe press would retain the internal lube system but neither shoe press needs a loading system.  Loading is varied by field strength and is absolutely flat across the machine width (no crowning).  Alternatively, the magnetic cores could be built in cross machine sections to provide infinite variability in a nip profile.


Depending on the shoe size, nip widths could be as long as you want which increases dwell time and decreases the total loading required.


A complete press section, with multiple, inline, "MagNips" could be designed without heavy framework to counteract and support conventional loading systems.  The cross machine mass of press components (press rolls) don't have to be designed for critical speeds or ring stresses.  The heaviest press component would be the magnetic cores. 


The benefits of this system would be smaller press sections, better felt life (lower peak loads), no press roll covers to buy and crown (just shoe blankets), much lighter press frame work, no huge hydraulic power units, lighter foundations. 


The downside would be power consumption but I'll leave that up to the experts to sort out.


We would like to hear from you. Please send an email to [email protected] 

with "LGMI Frontiers" in the subject line. 


Comment from last week:




My memory is that we always split the rope at points between separate drive speeds.


George Mead

Wisconsin Rapids, Wisconsin




LGMI Design Practices
As always, your comments will be appreciated.
Think light!


Brian Brogdon, Ph.D.
Executive Director




Jim Thompson

Send us your comments by emailing Brian Brogdon
or Jim Thompson!




LGMI Weekly Ideas are presented for your consideration and inspiration only.  It is solely your responsibility to check for engineering correctness, applicability, standards, insurance policy and local, national or any other legal compliance required before implementing.  Neither The Light Green Machine (TM) Institute, Paperitalo Publications, Talo Analytic International, Inc., nor any individual associated with these entities accepts any responsibility for your application or compliance issues.


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