Hi, just to clarify, I did not write what was attributed to me here.... my post
is further down!
>
> David Lisney wrote:
>> Deionized water can contain dissolved minerals that the demonizing
>> process cannot remove, namely dissolved silicates which are plentiful
>> in Florida water. (elsewhere I have no knowledge) These minerals do
>> get deposited in the cooling circuit and an acid rinse does not
>> dissolve them. (they are white glass like coating) I will add that
>> operating these high power tubes with water on their collectors
>> (through the Ammeter and overload relay coil) is made much easier by
>> grounding the collectors and supplying the high Voltage to the cathode
>> with the power supply terminal with the surplus of electrons. (the
>> negative terminal) * after 50 years and 5 months.
>
> I started replying, before I realised this was a troll! Very well done,
> and you had me for a second until I re-read your last sentence a few
> times! Point taken as well, that the water thing has been done to death.
>
> To be perfectly clear though, deionised water will be near "absolutely
> pure" - far purer that steam distilled water. I spent a year in the lab
> of a thermal (gas powered steam) power station, and they used the
> deionising process specifically to remove silicates and others.
>
> In any case, it is no matter as deionised "battery water" is available
> widely at auto-parts stores.
>
> KA4INM <ka4inm@gmail.com> wrote:
>
>> Water requires more energy per gram of liquid to change its
>> temperature. Water can hold more heat energy than oil.
>
> The heat-removal issue has already been resolved, and that level of
> cooling is not required. There is only about 5KW continuous, not 20KW.
>
> And as far as hoses blowing off after being double clamped and resultant
> oil-sprays, I think that is a nonsense. The hydraulic hose industry
> uses only single clamps, and they are rated to many thousands of PSI. I
> will be using solid steel pipework with Swagelok compression fittings,
> and there will be no more "blowing off" in my shack other that what is
> usual.
>
> I think I see the problem: People cannot get past their fears - having
> a highish temperature flammableish liquid in the shack.
>
> And at first glance, 4KV at 2amps right next to your cup of coffee is
> just as risky a proposition, BUT we build the amp properly don't we, so
> that isn't a risk. If I make "HT" mistakes building an amp of those
> proportions, then I shouldn't be building amps at all.
>
> Oil will be fine. Proper pump, proper steel pipework, proper steel
> fittings, and so on, done properly, just like your perfectly safe HT supply.
>
> Steve
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
> ------------------------------
>
> Message: 3
> Date: Fri, 17 Apr 2015 14:44:05 -0600
> From: John Lyles <jtml@losalamos.com>
> To: amps@contesting.com
> Subject: [Amps] Oil v water cooling
> Message-ID: <55317095.2020302@losalamos.com>
> Content-Type: text/plain; charset=windows-1252; format=flowed
>
> On 4/17/15 10:00 AM, amps-request@contesting.com wrote:
>>> Hi, I believe that not all "distilled water" is suitable for this, you may
> need to specify "deionised water". The water conductivity needs regular
> checking,
> it will rise as it gets contaminated by traces of solder flux etc...I
> seem to
> remember where in a published design for a watercooled amplifier that
> about 6"
> from the tube anode that the plastic cooling pipe went through a brass
> coupler
> that had a meter connected between it and chassis ground to monitor
> leakage current.
> Regards David G0FVT
>
> Yes, exactly. The brass coupler and meter just insert a volt meter into
> the water pipe, to measure the actual leakage current, like measuring
> the voltage drop across a shunt. Getting it calibrated is the trick. If
> you have 6 inches of pipe from the brass sleeve to ground and now the
> diameter, can calculate the resistance for a given value of resistivity
> of water.
>
>> As a retired* broadcast engineer with plenty of experience
>> maintaining vapor and water cooled transmitting tubes I highly
>> recommend ONLY "steam distilled" water over any deionized water.
>> Deionized water can contain dissolved minerals that the demonizing
>> process cannot remove, namely dissolved silicates which are plentiful
>> in Florida water. (elsewhere I have no knowledge)
>> These minerals do get deposited in the cooling circuit and an acid
>> rinse does not dissolve them. (they are white glass like coating)
>
> The literature from Varian + Eimac (CPI) and the other tube companies
> recommends deionized water. CPI website has this info in several app
> notes. By using proper resin bed followed by an oxygen removal stage,
> mineralization is not a problem. A continuous process through these
> bottles (available from Culligan and Cuneflow) will keep the water pure.
> This is industry practice, from companies like Continental Electronics
> to users such as our particle factory. In a closed loop system, the
> water must be continuously 'polished' this way, and the equipment is
> called, appropriately, the polishing loop. The bottles are replaced
> about once per year in the installations that I maintain/design.
>
> Steam distilled water might be a good starting point, but I cannot
> imagine that the closed-loop process includes a distillery and the
> incipient energy consumption required to continuously boil and re-
> condense a large flow of water in real time.
>
>> I will add that operating these high power tubes with water on their
>> collectors (through the Ammeter and overload relay coil) is made much
>> easier by grounding the collectors and supplying the high Voltage to
>> the cathode with the power supply terminal with the surplus of
>> electrons. (the negative terminal)
>> * after 50 years and 5 months.
>> -- Ron KA4INM - Youvan's corollary: Every action results in unwanted
>> side effects.
>
> Indeed, Klystrons and IOTS are typically run that way, with the
> collector grounded or just off ground (to measure body current from the
> voltage between the body and the collector to see how much beam is being
> spilled). Then the negative HV is applied to a floating cathode/filament
> with isolated heater transformer.
>
> For those of us using PGT (power grid tubes) though, we typically have
> B+ on the anode and have to insulate those pipes.
>
> Oil vs water:
> I like water only in that we always find leaks and water on the floor
> and equipment is a lot easier to clean up. The federal gov't doesn't
> like having oil spills, even indoors. Also, for the Specific Heat
> Capacity as Ron suggested.
>
> 73
> John
> K5PRO
>
>
>
>
>
>
> ------------------------------
>
> Message: 4
> Date: Fri, 17 Apr 2015 16:14:09 -0500
> From: donroden@hiwaay.net
> To: amps@contesting.com
> Subject: Re: [Amps] Oil v water cooling
> Message-ID: <20150417161409.35516ljqio500joh@webmail.hiwaay.net>
> Content-Type: text/plain; charset=ISO-8859-1; DelSp="Yes";
> format="flowed"
>
> Quoting John Lyles <jtml@losalamos.com>:
>
>
>> Then the negative HV is applied to a floating cathode/filament with
>> isolated heater transformer.
>
>
> Yah..... REALLY isolated !!!!
>
>
> Don ( remembering the old GE "Austin Ring" filament transformers ) W4DNR
>
>
>
> ------------------------------
>
> Message: 5
> Date: Fri, 17 Apr 2015 23:36:56 +0000
> From: "Fuqua, Bill L" <wlfuqu00@uky.edu>
> To: Manfred Mornhinweg <manfred@ludens.cl>, "amps@contesting.com"
> <amps@contesting.com>
> Subject: Re: [Amps] Oil v water cooling
> Message-ID:
> <B7E8B5B4A202074084E2515A7B10A7F34AEFD8C4@ex10mb02.ad.uky.edu>
> Content-Type: text/plain; charset="us-ascii"
>
> Oil cooling/bath was mostly been used either for tube power amplifiers used
> in high altitude aircraft where the break down
> voltage drops with altitude as well as cooling capacity of air or in high
> voltage DC power supplies for X-ray equipment or
> hv power supplies for research. We had one that was over 300kV and when we
> decommissioned it had to dispose of
> hundreds of gallons of oil.
> 73
> Bill wa4lav
>
> ________________________________________
> From: Amps [amps-bounces@contesting.com] on behalf of Manfred Mornhinweg
> [manfred@ludens.cl]
> Sent: Friday, April 17, 2015 3:27 PM
> To: amps@contesting.com
> Subject: Re: [Amps] Oil v water cooling
>
> I worked for 18 years at a scientific organization where we used a variety of
> liquid-cooled systems. For systems requiring the coolant to be near room
> temperature, or somewhat cooler, often close to freezing temperature, we used
> a
> water/glycol mixture. For very cold systems we used liquid nitrogen vapor
> phase
> cooling, and for even colder ones liquid helium. I can't remember any system
> using oil as a coolant, but maybe there was. I didn't know absolutely
> everything
> we had there.
>
> What I do know: Despite professional construction and maintenance, spills did
> happen. Small spills while connecting and disconnecting equipments, or from
> leaks in pumps, filters, fittings, etc, and large spills when something broke.
> It was very good to have just water/glycol spraying, flying and flowing
> around,
> rather than oil. Pure water would have been even nicer, but wasn't usable for
> us
> because we sometimes needed temperatures around freezing.
>
> I had to fix a few such problems. Among them was corrosion, both from the
> inside
> and from the outside; cavitation; material fatigue due to microvibration from
> the coolant's turbulence; and many others, difficult to list. Sometimes
> something heavy would fall on a cooling hose, sometimes someone would make a
> mistake, some hoses develop pinholes without warning, a barb might have a
> scratch making it leak, and so on.
>
> The simple fact is: Leaks happen. Liquid cooling is excellent in many
> situation,
> but one needs to consider the possibility of a leak. In my shack, if I have a
> water leak, it's less bad than spilling a cup of coffee. But an oil leak is
> very
> much worse!
>
> Technically, the lower thermal conductivity, heat capacity, and higher
> viscosity
> of oil requires a very much higher pump power, to extract a given amount of
> heat. That means a bigger, heavier, more expensive and noisier pump, that
> wastes
> more energy.
>
> On the other side, of course, oil has the advantage of being an excellent
> insulator, not causing corrosion, inhibiting it, also has a much lower
> dielectric constant and loss.
>
> With hoses, be careful. While water can support corrosion of metal, it's safe
> with hoses. Oil is safe with metals, but degrades many hoses!
>
> Both coolants have their places. But water has more of them.
>
> Manfred
>
> ========================
> Visit my hobby homepage!
> http://ludens.cl
> ========================
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>
> ------------------------------
>
> Message: 6
> Date: Sat, 18 Apr 2015 05:28:33 -0400
> From: "Roger (K8RI)" <k8ri@rogerhalstead.com>
> To: amps@contesting.com
> Subject: Re: [Amps] Oil v water cooling
> Message-ID: <553223C1.1060307@rogerhalstead.com>
> Content-Type: text/plain; charset=utf-8; format=flowed
>
>
>
> It's been a long time, but as John said, these solutions are ion hungry
> and particularly DI water. We measured resistivity at ohms per cubic
> centimeter,. It's not just solder, they will reduce a brass hose
> fitting to a dull copper color that you can crumble with your fingers.
> It also likes copper, to the resistivity monitoring mentioned several
> times is a necessity. We went through thousands of gallons of DI water.
> Oil can most likely be used on almost any water cooled tube, but water
> is likely, by far, the best for carrying heat away. I can't imagine
> using oil
>
> 73
>
> Roger (K8RI)
>
>
>
>> On 4/16/2015 12:13 PM, David Lisney wrote:
>> Hi, I believe that not all "distilled water" is suitable for this, you may
>> need to specify "deionised water". The water conductivity needs regular
>> checking, it will rise as it gets contaminated by traces of solder flux
>> etc...I seem to remember where in a published design for a watercooled
>> amplifier that about 6" from the tube anode that the plastic cooling pipe
>> went through a brass coupler that had a meter connected between it and
>> chassis ground to monitor leakage current.
>> Regards David G0FVT
>>
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