Preventing Stuck Swageloks?

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ian_krase
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Joined: Mon Nov 28, 2016 2:48 am
Real name: Ian Krase

Preventing Stuck Swageloks?

Post by ian_krase »

I have a problem with swagelok fittings, especially 1/8 inch brass swageloks on copper tubing, getting seized together -- I can unscrew the nut, but the cones on the tube don't come out of the socket.

How can I fix or prevent this? Is a thin sheen of vacuum grease on the larger cone ferrule an OK idea? Should I heat up the socket?
Dan Knapp
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Real name: Dan Knapp

Re: Preventing Stuck Swageloks?

Post by Dan Knapp »

Sounds like you may be tightening them too much. A new 1/8 inch fitting should only be tightened 3/4 turn past finger tight (1–1/4 turns for larger fittings).
ChristofferBraestrup
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Real name: Christoffer Braestrup

Re: Preventing Stuck Swageloks?

Post by ChristofferBraestrup »

It is pretty much unavoidable on brass reused fittings. Dont grease them.

A reused fitting with a crimped ferrule really only needs finger tightening + a small yank with a wrench - less than 1/8 turn.

I've had success with unscrewing the nut, then pulling the tube away and jiggling it wildly.
richnormand
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Re: Preventing Stuck Swageloks?

Post by richnormand »

Not much of an issue if torqued properly and a clean assembly.
However on a few eBay purchases with unknown history I had issues

Once the nut is loose I use a heat gun and pull gently.
In one case a few years ago that was not sufficient so I pulled the nut completely, a good amount of heat and while the assembly was hot a good blast of "Freeze Mist" for rapid cooling did the job.
ian_krase
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Joined: Mon Nov 28, 2016 2:48 am
Real name: Ian Krase

Re: Preventing Stuck Swageloks?

Post by ian_krase »

I really need to get a length of thin bellows hose with some Ultra Torr fittings.
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