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Re: NEON- Another cold cathode question
Lisa Scanlan wrote:
> He is interested in upgrading the pumping equipment he currently owns
> for higher production of cold cathode tubes. His question is: Has
> anyone been able to repeatably pump 2 8-foot 20 mm tubes, at once, with
> either the Eurocom 'Turbo' system, or the Voltarc Neovax?
Good question Lisa,
I don't know anything about the Voltarc Neovax, bit I am quite familiar
with the Eurocom Turbo system, so my reply is related only to that
station, and I can tell you that that station easy can do 16 feet 20 mm
tubes. I don't hink that even 18 feet will be hard to do for that
pumpingstation as it is very high tech and equiped with supurb parts.
Tough I want to make some remarks, namely:
ETS is equiped with a turbomolecular pump that has 60.000 rpm and that's
alot namely 1.000 rpm a second, can you imagine that? For that reason I
prefer the Alcatel hybride molecular drag pump as it can be switched to
36.000 rpm. Another "BIG"advantage of the more modern equiped with the
latest technolgy hybride MDP pump lies in the fact that the priming
pressure of the MDP is between 30 and 60 mbar while the priming pressure
of the TMP is lower then 1.10 E-2. Just for that reason I always prefer
the Alcatel pump instead of the Leybold pump as the MDP is fully in its
operating area when I need pumping speed the most and that is from 5
mbar. The TMP pump is coming into its operating area two decades later
(lower) and I always found that STRANGE. Even the ordinary DRAG pump
have a better performance compared to the TMP "FOR OUR BRANCHE". We must
have full pumping speed at from 1 mbar to below 1.10 E-4 so I prefer the
Alcatel pumps as the character of these pumps are just in the operating
area we need to have full pumping speed the most.
The backfilling system of ETS id perfect, but what's the deal. There is
a cannister who everybody can buy and a set of valves and a pressure
regulator which you can buy standard from Messer Griesheim the rare gass
supllier.
The bombarder of ETS is very good, but what's the deal, several European
transformer manufacturers are producing electronic controled remote
controled bombarding equipment like that and it should be wise to
compare prises to each other.
The turbomolecular-dragpump I refer to is the Alcatel pump with a wight
of 1.2 kg (for you 2.7 lb) and is a big as a package of cigarettes. The
backing pump can be every rotory vane pump no matter the capacity, but I
prefer the 2 qm an hour pump. (qm is quebique. meter, don't know how to
transfer that into your system)
The ETS has a backfilling manometer from Leybold called the DIAVAC. Good
meter, nice meter, you just can outread half a milibar, but what should
I do with a so expensive meter that is seperated from atmosphere in his
own vacuum clock as the lifetime of the meter is given by Leybold for
only two years. After two years the meter must be recalibrated and the
cost of that is only 10% lower then bying another meter.
For that reason I prefer the BOURDON manometer ( I always buy for the
pumping stations we build the one from EDWARDS, cost half the price)
with the scale 0-25 mbar. The bourbon is more solid and why should I buy
a meter sepearted from atmosphere? Only when you must backfill pressures
like 800 or 900 milibar then it is importand that the meter is seperated
from atmosphere, as then the outreading can depend on the atmospherical
pressure. As you know the pressure can vary (roughly) from 980 mbar to
1030 mbar (in extremes) So when you must backfill to a pressure of 900
mbar it is important that the refernce point from the meter is not the
atmospherical pressure otherise 900 mbar backfill pressure can be 925
mbar in real. But for our trade with average backfilling pressures of 15
to 20 mbar we can ignore that fact. Let's say we backfill 10 mbar (easy
number) and the atmospherical pressure is not 1000 mbar but 990 mbar,
what's the deal. The backfilling pressure is 100 times lower so the
misreading of the meter is simular to that. So the misreading is only
0.01 mbar and we can ignore that completely.
So don't get impressed by big number but know what you must do with it.
Looking to the above and to your statement that probably nobody would
react I will ask you" hey dear Lisa there is this list for. To prevent
costly mistakes and to exchange knowledge and ideas. For what reason did
you put it that way? Show your boss this reply and come back to me, in
private or on the list whatever you or your boss prefer, but I prefer on
this list) if you have more questions.
Oh the bombarder must be well regulated with the correct charcteristic
of course with an open volateg of 15 kV and must can do 1000 ma, so the
15 kVA one. A two phase bombarder is of course more elegant to use
because of the lower primary current and thinner wires.
Hope this helped, and ask as only asking questions can produce answers
to the people who need that.
Meanwhile is signing from a dark and wet Rotterdam after a long evening
at school for the nite course, together with his best regards
from dirk a. boonstra.
OHH. The phone number of Alcatel in your country is 617 331 4200 and
tell your boss that I want to receive the comprehensive documentation of
the ATH 20/40. That's my baby. And for the other members of this list
who are interested, ask for the documentation as well as it is very
interesting. Faxnumber is 617 331 4230. To make it clear for you all:
there is no relation between dirk boonstra, or his company, and Alcatel.
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