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Nip Impressions® is Paperitalo Publications' flagship publication.  Published every Thursday afternoon (US Eastern Time), Nip Impressions® is eagerly read by pulp and paper professionals around the world.


19 Nov 14: Does Mass equal Security?
LGMI R
 

As I have been saying for the last couple of weeks, there were many things that came out of the recent LGMI conference that left me in a contemplative state.

 

One of our speakers expressed frustration toward acceptance of the concept behind the Light Green Machine Institute, which he managed to express more succinctly than I ever could.  This concept is a profound and foundational one.  The speaker came away from the conference with the belief that the attendees largely take comfort in the idea that the heavier something is, that is the more mass it has, the more reliable it will be. 

 

If this is true, this is a major barrier we must overcome.

 

We'll start exploring this concept right here and now.

 

I want to start by saying that not all mass is equal.

 

Let me explain.  Mass has relative value based on the cost of the mass.  Copper, we have previously identified, is often the costliest mass we see in paper mills. On the other end, concrete, or even in some cases, soil, are the least costly masses we encounter.  Steel and its alloys lie somewhere in the middle, while aluminum is toward the high end.

 

One way to think about this is the common tower crane one sees on building sites, especially high rise construction sites. Notice that the counter-balance end of the crane is much shorter than the lifting end.  Why is that?  If this were a child's "Teeter Totter" or a simple lever, both ends would be of similar length. 

 

However, we are in a world where cost matters when we consider the tower crane.  Hence, the counter balance end is expressed in a much shorter expanse of steel structure (as compared to the "working" end) accompanied by a large weight made of (relatively cheap) concrete.

 

However, the crane is not just a two dimensional structure.  If you consider only the "x" and "y" axes, it indeed does look two dimensional and the counterbalance must react against the vertical load being lifted.  However, the crane also has a "z" dimensional component, as represented by its rotation.  Although the WK2 factor of this component, when taken in its entirety, should be the same with a relatively small weight at a relatively long distance vs. a relatively large weight at a short distance (if one considers the structure from looking down from above) the cantilever beam of steel for the short distance, large concrete counterweight, is still more economical than the long steel structure with a relatively small concrete counterweight.

 

I probably have you confused thoroughly by now, but the basic condition I was trying to demonstrate with the out-of-our field crane was that mass must be considered so very carefully, especially when cost comes into the picture.

 

Right now, I would like your opinion and answer to a simple question:  In your mind, in a pulp or paper mill, does mass equal security?  You may answer this one simple question here. We'll share the results in an upcoming issue.

 

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

 

Brian Brogdon, Ph.D.
Executive Director

 

or

 

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

 

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