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How good is brass compression fitting in vacuum?

How good is brass compression fitting in vacuum?

How good is brass compression fitting in vacuum?

(OP)
BACKGROUND

I need to maintain a metal plate at 25 plus minus 0.5 deg C. The plate is 6 x 150 x 600 mm (1/4 x 6 x 24 in). I plan to braze a copper tubing to the place and flow water through the tubing. The setup sits inside a vacuum chamber, 10e-5 torr, not a high vacuum.

QUESTION:

The soft copper tube will be soldered to a brass socket fitting. How tight is brass socket fitting? Good enough to be used in vacuum?

Thanks.

RE: How good is brass compression fitting in vacuum?

OFHC Copper is used all over the place. We have He Mass Spectrophotometer's that use Cu gaskets and some brass parts.  
I can't see where a brass fitting wouldn't be  equivalent to the Cu tubing being used.
I have pulled some pretty high vacuum on Cu tubing for He leak testing and haven't had any problem with either brass or Cu fittings  

RE: How good is brass compression fitting in vacuum?

Compression fitting quality varies among manufacturers.  Some of my clients permit knockoffs for their standard transmitter installations and only the brand name for their analyzers.  Don't even consider hardware store fittings.

RE: How good is brass compression fitting in vacuum?

(OP)
Thank you for the replies. I now feel better now putting the cooling water line in the vacuum chamber.

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