Correct compression fitting?

[HappySalesman]

Firstly, I'd like to say hello! Long time lurker, first time poster. The amount of helpful info I've found here is innumerable.

Now on to my question. I have a 60 gal 2 stage compressor, that I'm adding a cooler to between the pump and the tank in preparation for an automotive paint project. I've got a list of parts ready, and I want to make sure I have the correct fittings. This is what's currently on the compressor:




This at the pump. I am assuming there is a similar fitting at the tank.

I'll be the first to admit that I'm a newbie when it comes to standard plumbing connections like this. Most of my experience is with AN fittings, so if this is a dumb or silly question, I apologize.

That being said, number one, this is a compression fitting, correct?

If it is, assuming I get the correct size (1/2") a standard compression fitting should connect right? As in, this isn't some odd-ball type of fitting?

and lastly, is the crimp in the copper pipe necessary? I've seen some instructions online showing one, and others saying you just slide the nut and sleeve on then tighten it down.

Thanks!

 

[jubilee]

Looks like that connection was severely over tightened

 

[carlaisle]

That was a compression fitting. It's an abomination now. That should be cut off and replaced. The CFM will be a better indicator of the size than the tank. I would guess it's probably 3/8" pipe/1/2" tube. Take it with you to the store and match it up on site to eliminate guesswork. Keep in mind tubing is measured by outside diameter, not inside diameter - the exact opposite of pipe.

That pretty well covers the install process. Make sure the copper remains fully seated while you're tightening the compression sleeve. If there's any latent tension sometimes they'll try to slip out and then you'll end up with a bad seal and redoing your work.

If you're installing an aftercooler, you would be wise to include a condensate separator between the cooler and the tank. If you're planning to paint (and this isn't an oilless compressor), you'll also want a coalescing filter, some fine filtration, and almost certainly a dessicant dryer of some kind - an inexpensive inline often works - depending on how dry your air is and how much flow you need.

 

[PCustoms]

Doesn't look like a standard compression fitting to me, note the angle:

 

[HappySalesman]

That was a compression fitting. It's an abomination now. That should be cut off and replaced. The CFM will be a better indicator of the size than the tank. I would guess it's probably 3/8" pipe/1/2" tube. Take it with you to the store and match it up on site to eliminate guesswork. Keep in mind tubing is measured by outside diameter, not inside diameter - the opposite of pipe.

If you're installing an aftercooler, you would be wise to include a condensate separator between the cooler and the tank. If you're planning to paint (and this isn't an oilless compressor), you'll also want a coalescing filter, some fine filtration, and almost certainly a dessicant dryer of some kind - an inexpensive inline often works - depending on how dry your air is and how much flow you need.

The compressor is listed at 16.1 CFM at 100psi.

Im not sure where the damage came from, this was the first time I've removed the pipe and I bought the compressor new. The nut didnt feel particularly overtight when I removed it, how much torque is usually used on a compression fitting?


And I do have a filter planned in-line between the cooler and the tank. I also have a 3 stage filter/drier for my output to the spray gun. I live in a fairly humid area (central Indiana), but I'm aiming to actually be painting in the fall when things cool off and humidity isn't quite so bad.

 

[BrandonV]

Im not sure where the damage came from, this was the first time I've removed the pipe and I bought the compressor new. The nut didnt feel particularly overtight when I removed it, how much torque is usually used on a compression fitting?

Just enough to seal. General rule of thumb I like to use is to tighten it gently, check for leaks, and repeat in small amounts tightening until there aren't any leaks.

When the tube is crushed like that, the ferrule will be compressed to a point where the nut won't feel particularly tight at all.

 

[MacMcMacmac]

1 1/4 turns from contact on a new fitting. 1/4 turn when retightening an already installed fitting. The picture is a perfect example of why compression fittings are illegal for repairing brake lines.

 

[housewolf]

I’m almost positive that’s some sort of proprietary fitting and not a standard compression ferrule. I don’t think it would be possible to form a ferrule like that be over tightening. Maybe, but I’ve never run across it

 

[MadMechMaster]

I recently bought a compression fitting with some sort of captivated ring as part of the nut. Looks like the photo had the nut removed and slid back. Garbage. I'll be paying better attention next time.

 

[Sumboodie]

The compressor is listed at 16.1 CFM at 100psi.

Im not sure where the damage came from, this was the first time I've removed the pipe and I bought the compressor new. The nut didnt feel particularly overtight when I removed it, how much torque is usually used on a compression fitting?


And I do have a filter planned in-line between the cooler and the tank. I also have a 3 stage filter/drier for my output to the spray gun. I live in a fairly humid area (central Indiana), but I'm aiming to actually be painting in the fall when things cool off and humidity isn't quite so bad.

That pic is the main feed line from pump to tank?

For 16 cfm, should be a decent size line, like 3/4". The pic makes it look small, like 1/4" or maybe 3/8"

 

[housewolf]

I recently bought a compression fitting with some sort of captivated ring as part of the nut. Looks like the photo had the nut removed and slid back. Garbage. I'll be paying better attention next time.

A swagelok fitting has two ferrules. Not garbage by any definition

 

[HappySalesman]

That pic is the main feed line from pump to tank?

For 16 cfm, should be a decent size line, like 3/4". The pic makes it look small, like 1/4" or maybe 3/8"

That is the main feed line. I measured with my calipers and the OD is 5/8", so im assuming the ID is 1/2"

 

[BrandonV]

I cranked down on a piece of utility tubing which has a pretty thin wall with an adjustable wrench until the compression nut bottomed out as a test for those interested.

For the OP. If that's a compression fitting someone really cranked down on it...

 

[mike93lx]

I cranked down on a piece of utility tubing which has a pretty thin wall with an adjustable wrench until the compression nut bottomed out as a test for those interested.

For the OP. If that's a compression fitting someone really cranked down on it...

Now it's ribbed, and for no one's pleasure

 

[MadMechMaster]

A swagelok fitting has two ferrules. Not garbage by any definition

Just googled Swagelok, not that. Looked more like what the OP's fitting has if it were removed from the nut.