We are manufacturing our vacuum systems in our mechanical shop:
http://www.itim-cj.ro/echipamente
unfortunately nothing in English here.

However, a good valve for vacuum is also a good valve for 200bar.
It does not use balls, but a needle tip.
You can see the picture here:
http://www.itim-cj.ro/images/atelier/mediu/robreglarefinadn2.jpg

such valve must use a motor for spinning control.
I'm sure you may find something suitable. Will not be cheap.

good luck,
Vasile


On Sun, Nov 1, 2015 at 8:07 PM, David VanHorn <microbrix@gmail.com> wrote:

> I have a vacuum project in the works, and I've just isolated one source o=
f
> leaks.
> The system needs three shutoff valves.  I used ball valves, and I'm findi=
ng
> that they are leaking. Probably designed for positive pressure I'm
> guessing.
>
> Is there someone on the list with vac experience down around 20 microns w=
ho
> could suggest relatively inexpensive valves that I could use?   The syste=
m
> is now built with 1/8 NPT but I could switch if I need to.
>
> These valves just need to be on or off, and they are used for controlling
> the flow of air and other gases. No liquids, nothing harsh.
>
> Thanks.
> --
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> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
>
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