The Final Frontier
Paraphrased and dramatized by Cynthia Waters
http://groups.yahoo.com/group/allplanets-hollow/message/1246
(from group archive)
In
August of 1980 in the southeast United States, problems were being
experienced at a polypropylene plant. Strange things were happening
around a film slitting machine.
David
Swenson of 3M Electrical Specialties Division in Austin, Texas was
called in to investigate. Little did he know that he was about to enter
the final frontier. When
Dave asked what type of problem they wanted him to look at, he was told
that he would have to come to the plant. They could not explain it over
the telephone. They did tell him that they were experiencing problems
with contamination of wide web film as it was being run at high speed,
converted (split) into "film jumbos" with a width of 3' x 5' for coating
with adhesive to make tape. Dave didn't see what was so unusual about
film being contaminated by dust, flies, other insects and... birds. "Birds"?
Now
they had Dave's attention and he didn't hesitate to go to the plant to
see for himself how birds could be caught up in film.
The
Polypropylene web was 21 feet across - almost the width of three lanes
of traffic on the interstate. The film ran from one roller up 20 feet
to another roller; across 15 feet to a third roller; down 20 feet to a
splitter; and was then wound onto two rolls. It formed a huge dynamic
"tent". On
the morning that Dave intended to measure the static electricity inside
the web tent , the temperature was 80°F with a relative humidity of 75
to 80%.
As
he walked toward the web with his field meter in hand, the machine
operator said "I wouldn't do that if I were you. Strange things happen
inside the web tent this time of day."
Dave
paused and thought about what the man had said but he was there to do a
job and that was what he intended to do. You see, Dave is a very brave
guy. Besides, it was just film running on a splitting machine. He had
seen that many times and nothing seemed particularly unusual that
morning. That is, until he looked down at his static field meter.
With
a 200kV @ 12" measurement device, the voltage measurements were off the
scale and he was still 20 feet away from the web! For the meter to be
pegged at that distance, the amount of static electricity had to be in
the Megavolt range. He thought to himself "Van de Graaff would be
proud!"
Since
he had come this far, Dave decided to enter the web anyway. As he did
so, the hair on his head, arms and entire body began to stand on end.
Even worse, he began to feel like sparklers were hitting him all over
his body. It felt like burning sensations at hundreds of points all over
his being. (brave? - hummm?) At
exactly one-half way into the web, David slammed into a wall that was
both invisible and impenetrable. It felt like he had hit a force field
like he had seen on Star Trek.
Although
he knew this was Coulomb's Forces - the law of static attraction and
repulsion - he was held in place for what seemed like ages as he tried
to grasp what was actually happening to him. It's one thing to know
about Coulomb forces, but it is quite another to feel them with such
gusto. When he finally came to his senses, he had to literally "peel"
himself off of the invisible wall.
As
he backed out of the web, he saw a fly drawn right up into the film and
wondered if conditions ever existed inside that web that could actually
draw a person up there as well. Dave
hurried to talk with the Plant Manager and excitedly explained what had
just happened to him. The Plant Manager agreed to go to the web to see
for himself what was going on. By the time he was able to go, however,
it was later in the day and the temperature and relative humidity had
risen. He was able to walk into the web and from one side to the other
without experiencing anything at all unusual. He told Dave that he
thought he was simply hallucinating. When the machine operator
corroborated Dave's story, the Plant Manager agreed to meet early the
next morning to see if the same conditions would exist as they had
experienced earlier in the day. They
met bright and early the next day. As the Plant Manager entered the
web, his curly gray hair immediately straightened. As he strutted toward
the center of the web, his confident gait suddenly came to a complete
stop as he hit the wall of invisibility.
Once he peeled himself off of the force field wall, a shaken Plant Manager came out of the web and exclaimed...
that he "didn't know whether they should fix it or sell tickets".
They decided to fix it.
Conclusion Static
Electricity can cause some very strange and often difficult to explain
phenomena. It is easily controlled if a commitment is made. This
nuisance can be reduced to a non-nuisance level by proper analysis and
installation of suitable equipment, at a very low cost.
Corrective Action An
induction static eliminator was installed across the web at the unwind.
The static electricity was immediately reduced throughout the process
to less than 50kV (from MV's). It was then possible to make measurements
in the rest of the area. Additional induction units were also installed
at the jumbo wind-up areas which resulted in less than 5kV at
conclusion.
Editor's Note We
would like to hear your explanations for Dave's adventure. Please give
us any similar experiences you may have had. We will publish these in
the next issue. Maybe this will become a series - "Weird Phenomena."
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