valve for throttling

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Richard Hull
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Real name: Richard Hull

Re: valve for throttling

Post by Richard Hull » Mon Nov 27, 2017 5:48 pm

In the end, a good total isolation valve between the chamber and the secondary pump is the best idea, overall. This is especially true with a diff punp.

A stock 2.75 conflat, manual right angle bellows valve is one of the very best choices here as it can completely isolate as well as throttle the secondary pump from the fusor chamber. Some gate valves do isolate others do not. The non-isolation gates are often purposely made to allow a specific "pass-by" conductance for a specific system design. I have one 4" gate valve with a 1/2" hole bored in it off to one side! I have another of the same size where a butterfly plate will not close fully.

Before you use a gate valve, know exactly what you are using or you may find it a deuterium gas "waster" once in a finished fusor system. This would force more gas flow through and then out of the system due to a gate valve that is incapable of a closure to allow for "fusor specific" differential pumping. I have a full closure 2.75 conflat bellows valve and I have to fully close the valve and barely crack it against my diff pump to conserve my deuterium. If you have never operated a fusor, take this advise to heart.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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