Remove oil from compressed air - question?

graham-xrf

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With great help from folk here, I now have a nice SGS regulator with air filter and water trap (the blue one in the first picture), and some 1/4" taper seal threaded couplers.

SGS Regulator.jpg_ _ _ _Air filter lubricator.jpg

I looked hard in descriptions, and the user notes that it came with, and there is simply zero mention of oil, nor whether oil is removed or not!

I searched among loads of compressed air products, and all those I see with the two part construction, the second is always a "lubricator", like in the second picture. I do understand that some folk who use a lot of air tools that need oil, choose to add in the oil at some point in the air line. I will not be doing that. The kit I bought has a built-in regulator, and would be the primary regulator and water trap, right at the compressor. Some folk might choose to have a special separate outlet at the bench, with a second trap and drain fitted right there.

I want to keep the air lines clean. Some of my new air tools have a oil lubrication point, but I also have these small inline lubricators to fit right at the tool, should I need it.
Like these -->
Inline Oiler.jpg

I want any oil at the compressor outlet to be removed somehow, and not contaminate the pipes. My compressor is the type that does have oil, and some will end up in the air if I don't clean it up.

Does the oil just end up in the water trap?
I would much appreciate if someone could explain exactly what it takes to remove oil.
 
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I only have 2 filter regulators on my oil air compressor, no lubricator, & no dessicant. I've never noticed any hint of oil coming out of my air lines. But that doesn't mean there isn't any, I don't do any painting or bead blasting with it so I can't tell.

Over the years one set of my filters have turned pink, not yellow as I would expect from oil, & the water that accumulates doesn't look milky. I do notice a bit of white when I purge the moisture from the bottom of the tank but that's what I prefer to see rather than any hint of brown.

Some shops I've been in & guys on the tool forums I've seen run these. I have no idea how effective they are for filtering out oil but that's one of the features listed for them. I'm sure there are other brands that do the same but this brand seems to be quite popular.


71vrvmwiKML._AC_SL1500_.jpg
 
I use a secondary coalescing filter which are specifically designed to remove submicron oil, water, and other liquid droplets. I use it after a standard air filter, and also have a mechanical auto drain on the compressor tank. If in a high humidity area, then one might add a centrifugal (spinner) filter first to take out the majority of water. If you have a 2 stage compressor then you would want to make sure the filter is pressure rated high enough. I like the Norgren filters, I run 1/2" NPT fittings with 1/2" with 3/4" lines for a 5Hp 2 stage compressor. I have drain valves on all my drops, but never have gotten any water out of them.


20200211_174919.jpg
 
I'm a fan of Norgren. I'm running 2 basic FRs & a couple of their mini regulators on my piggy back air tank & at the mill.

They have been trouble free for over 10 yrs now except for the occasional bowl oring replacement.

I've switched to battery power for all my automotive tools so I don't use air much anymore these days.

20161212_211851.jpg
 
I used this filter system, I do cerakote and bead blasting and couldn't be happier with this system.

Edit to add: I also use my plasma cutter with this filter system, And it eliminated the issues I had before with moisture.


1670255584575.png
 
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Thanks for the reply - and the picture. It is, of course, 2 sizes bigger than mine. :)
For my kit, I have purchased a water trap with built-in regulator, that can replace the regulator only cheapo thingy that the compressor came with. Then the next is a quality Norgren micro filter with oil remover, apparently all in one. I have not yet explored it fully, but I see the transparent bulb comes off with a bit of a twist, from a bayonet type fixing, and at least one cylindrical cartridge can come out. At least to get started, this might do.

One thing I had not paid much attention to at the beginning was, despite that the 100 Litre size (about 26 gallons I think) was one of the "bigger" compressors in the Hyundai range I could see, it has only 1/4" size fittings at the output pipe. I know the pressure loss depends much on the length of the pipes and hoses, as well as their cross section area, so this one "pinch point" may not matter much. Anyways, rather than get up to a pipe modification on the (new) compressor, I simply bought kit to fit.

If I end up needing critical use hyper clean air, I may add a third stage, like yours.
 

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FWIW, we've had excellent results from Tsunami brand oil coalescing filters / water separators at our body shops. New water-based paint systems require absolutely oil-free air in the system headed to the paint booth for decent results. Not cheap, but nothing that is of any quality ever is...
 
FWIW, we've had excellent results from Tsunami brand oil coalescing filters / water separators at our body shops. New water-based paint systems require absolutely oil-free air in the system headed to the paint booth for decent results. Not cheap, but nothing that is of any quality ever is.
Thanks for the recommendation. :)
I have used compressed air before in my career, but only as a user who expected it to already be clean enough for what was under way. These jobs sometimes came with hazards that had to be anticipated and managed. It was about things like hot isostatic press (900 bar and 1200C) Having air clean enough for critical quality spray painting, like you do, may be at lower pressure, but it's a whole new game, as is, I think, also media or vapor blasting.

Air driven power tools, like brad nailers, die grinders, and the like may need some oil, whether given directly a bit at a time, or using inline oilers right near the tool, is the way I intend to go. I will not be having my air pipes getting oiled up. I did deliberately choose a compressor type that uses oil. The slow running kind with step-down pulley system and large volume cylinder, known for longevity, reliability, and dramatically lower noise. I always knew I would have to process the air to remove oil.
 
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