Water cooling Power Tubes

[thedoci]

i am planing on building something with a water cooled power tube, and i was wundering how exactly should i buid the jaket to cool the tube, shuld i just emerse the anode in a water bath like a vapor cooled tube, or should i build a pipe coil on the anode (with some brass or bronze or copper inbetween) that runs the water threw it.

i am asking because i didnt finde a lot of infos on the subject of watercooling a power tube.

the disapation of the tube is a few KW´s

[GloBug]

You could fill an aluminum, brass or copper tube with salt and wrap it around a die of the same diameter, might not be enough cooling though for your application.

What about just suspending the tube upside down in a coolant?

[M Gregg]

I have seen it done on thyratrons..

The problem with the system was the water became contaminated by metal from the tubes and bypassed the rubber insulators..leakage detecting circuits were used..I have very limited experience with this...I guess some on here have much more..

I guess you have seen this:
Vacuum Tube Liquid Cooling

The leakage I refer to is electrical conduction across the insulating boundary into the cooling equipment..


Regards
M. Gregg

[v4lve lover]

wont work tubes will crack if water is cold and tubes start heating up

you might just use oil instead . but still WHYYY get some radiation cooled transmitter tubes .

[GloBug]

Well one would assume the tube and the water was at the same ambient temperature to start off with. Think of a fish tank heater.

You could google and see what guys are doing with brushless motors, the odd one makes their own jacket from brass. Not to many do though as standard size water jackets are available for under $10.

Go old school DIY and get a thin sheet of brass, some spigots and solder.

These look a little ghetto but you get the idea.

Homemade Water Jacket PiX - Blast - Traxxas
Custom Water Cooling Jacket - Rum Runner Racing

[thedoci]

to answer th "v4lve lover", the tube is designd to be water cooled, its got a copper anode so water cooling, its not a litle amp tube. and i dont think that i will finde a water jacket for a tube like the GU-5A or the GU-10A or simuler power tubes. and making a jacket isnt the problem, its the "how it works" that im interested it. (how i need to cool the anodes)

[thaumaturge]

Vapor phase is a genuine PITA. I'd stick with direct cooling of a tight fitting jacket with thermal compound between it and the tube. One way to construct such a jacket is to cast a mold with plaster paris and then use mold to either electroplate or manually form aluminum or copper sheet. To start electroplate vapor vacuum deposit aluminum on inside of mold. You may wish to do some clearancing in mold to deal with jacket thickness.

But... suspension in Dow Corning silicon oil would probably be simpler.
Doc

[tomchr]

Would you post a picture of your tube? Perhaps, we could help you a bit better if we had a better idea of what you're looking at.

Yeah... Some sort of non-conductive oil sounds like the stuff to use in this application. How about transformer oil?

~Tom

[thedoci]

http://frank.pocnet.net/sheets/018/g/GU5A.pdf
thats the datasheet of the tube, the tube itsself is still in shiping, so no picturs, sry about that, but if you look at picturs on google, you will get the idea.

[M Gregg]

The link in my previous post 3# shows a working tube cooler


Just for interest
M. Gregg