Air fitting on a tank / Plumbing Compressed Air

by John

I am trying to mount an air fitting to a tank.

I would like to know how to seal it properly so that air does not leak up the threads of the fitting.

I need also to mount a pressure gauge which will have the same problem: How to prevent leaking around the threads of the gauge.

I have tried many different methods, but all of them still permit air leaks.

Any help or advice will be appreciated. If this is unclear or not specific enough, please ask for further clarification.

Thanks,

J. B.

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Bill answers....

Hello John:

You don't indicate what methods you've already, and unsuccessfully, tried to stop your fitting threads from leaking...so I'm probably going to tell you about some you've already tried.

First off, products used for thread sealing do two things. They lubricate the threads so that the fitting can thread farther into the female boss, and then, depending on the type of sealant, they “set up” creating a strong, leak proof seal.

Many brand of modern air fittings come with a thread-sealant already installed on the fitting threads, so the user doesn't have to do anything to get a good thread-to-thread fit and seal.

That thread-sealant is Teflon based, and is available at hardware stores for home and industrial users.

Why does your fitting leak?

Is it possible that you're trying to thread a metric fitting into an imperial-threaded boss? For example, a 1/4” metric fitting will start to thread into an imperial 1/4” boss, but there won't be enough thread contact when it tightens to prevent leaks.

Are you using a sealant of some type? If not, do. That will make all the difference.

Last, are you able to screw the fitting in tightly? They have to be more than hand tight usually.

I hope this helps, John.

Cheers,

Bill