Dry air from a compressor... is it a Myth?

[Strouty]

I am having some trouble with my plasma cutter, and have finally figured that it is moisture in my lines. I probably should have been able to figure this out long ago, but I guess I just didn't think about how important dry air is. I know you can buy air dryers (I am currently looking at used ones), but I was thinking about using an air conditioning condenser from a truck. They seem to be rated for more pressure than my compressor puts out. I have seen a few people using them from cars, but I don't know if the CFM will be reduced. Has anyone done this before or do I need to get a specialized after cooler type radiator? I am also in process of getting an automatic drain, electrical disconnect, and an hour meter.

I have an Ingersoll Rand 2475 80 gallon 7.5 HP that makes 175 PSI and 23 CFM. I do not use it everyday, sometimes it gets used once a week. I was wondering if I should go with a float style drain or one that comes on with each cycle of the compressor (air actuated?). I know there are some other threads dealing with this, but they seem to die before getting all my questions answered. I am going to try and keep this one alive long enough to get some good ideas and good pictures.

I saw this drain from Northern Tool and wondered if anyone had any experience with it?

http://www2.northerntool.com/item-19.htm

 

[volvo92906]

In a truck shop I used to work in, when we were using the compressor a lot to the point where moisture was building up in the system, we made a 5 gallon bucket with a coiled up air line in it. It was filled with water. The air would actually cool off going through the bucket and there would be no moisture. Same principle as your condenser, but I do not have experience on that.

Air dryers ALWAYS help though.

 

[Strouty]

In a truck shop I used to work in, when we were using the compressor a lot to the point where moisture was building up in the system, we made a 5 gallon bucket with a coiled up air line in it. It was filled with water. The air would actually cool off going through the bucket and there would be no moisture. Same principle as your condenser, but I do not have experience on that.

Air dryers ALWAYS help though.

Sounds like what they make too cool fuel down for drag cars. I never thought of anything like that.

 

[CNGsaves]

So you have a 23 CFM air compressor . . . . but skimpy air line system that doesn't help pull out moisture? Show some pics of your compressor setup and air line system.

Your driest air is going to be FARTHEST from the compressor. Easiest/cheapest route to dry air is black pipe Franzinator, then black pipe air line system, then coalescing filter/dryer at the farthest drop.

Money can get you whatever dry air you want with dessicant dryer, powered cooler, etc. All comes down to how big check you want to write!!

 

[Buckgnarly]

I have a zig zag of about 8' of copper 1/2" pipe right at the tank, water trap at the regulator (about 30' of 1/2" copper later) and finally another moisture trap on the plasma itself. I also have two lengths of copper with drains along the way to catch moisture.

Never had moisture problems, in fact never even got any moisture in the one on the plasma.

 

[bsaint]

Three words. Refrigerated air dryer.

 

[rslaback]

Three words. Refrigerated air dryer.

I don't mean to steal the thread...


How world you test a RAD? I have one I salvaged From a HVAC control system but no idea how to bench test it.

 

[evintho]

As far as dry air, I have an IR 80gal 5hp and I run a water trap 5' off the compressor then I run this portable contraption near the end of the line. I sandblast with a 90lb pressure pot all day long and not a drop of moisture leaves the line. It's just an old water trap connected to one of those toilet paper filters I got off of Ebay. I just hang it on the fence near where I'm blasting. Dirt cheap and works like a charm!

Also, instead of a $120 automatic filter, $5 in plumbing parts will do the same job. You do have to bend over and open the valve, though!

 

[BrokewrenchLS1]

Three words. Refrigerated air dryer.

This. We had to install one for dry air to a $250,000 piece of equipment and you can't get dryer air than on the other side of that refrigerated dryer.

 

[cide1]

I have a moisture trap on the outlet of the compressor, and then go straight up to the ceiling to about a 12 foot run across garage, then another moisture trap, then a 50 ft hose reel into back of plasma cutter. With this setup, I have no issues with moisture, which I attribute to the long run between two traps cooling the air, drawing the moisture out.

 

[454ragtop]

Some compressors are worse than others, especially as regards to comp. speed. I have a large old industrial compressor that turns very slow, generates very little condensation.
Jim

 

[skulldrinker]

I thought of this when i was into doing body work and spray painting and it kept my air dry. I took a 50' roll of copper and hooked it up to the outlet in the head ran it down through a hole in the wall and ran it outside. I buried the coil under ground and then ran enough back into the garage into an inline filter and then into the top of the tank. The inline filter removes all the water and nothing "ZERO" of water goes into the tank. I have had this setup for about 25 years and there is no degrade of performance of the compressor output. I have the drain in the filter cracked open a hair so it never collects.

 

[larryq]

Someone I know took an old dorm room refrigerator, drilled two holes in either side and coiled 25' of copper tube in there, and stuffed the slack in the holes with insulation material to keep the cold in. It works for him!

 

[kc-steve]

Ambient air in terms of relative humidity makes a difference too. I don't know what Maine's air is like, but here in KC I can get by with using steel pipe for cooling (approx 30'), a moisture filter at the pipe's end, and a desiccant filter at the paint gun for painting. Works fine for me.

Steve

 

[243]

I used this diagram from Sharpe as a guide. I used a 3/4" flexible hydraulic hose from my 60gl upright to the wall, ran up to the ceiling with 3/4" copper, 25' to the back of the garage and 25' back, dropped down to a HF dryer, down 2' with a dead leg and drain.

Works great in hot-humid Central Texas in the heat of summer sand blasting, priming and painting.

 

[Strouty]

I thought of this when i was into doing body work and spray painting and it kept my air dry. I took a 50' roll of copper and hooked it up to the outlet in the head ran it down through a hole in the wall and ran it outside. I buried the coil under ground and then ran enough back into the garage into an inline filter and then into the top of the tank. The inline filter removes all the water and nothing "ZERO" of water goes into the tank. I have had this setup for about 25 years and there is no degrade of performance of the compressor output. I have the drain in the filter cracked open a hair so it never collects.

I really think this is one of the most inventive ideas, seems too simple, but I may just try it. I would like to have a refrigerated dryer, but they are pretty expensive. I do not use the compressor enough to warrant the cost. If I get into painting or something like that I may end up investing in one, but this idea will probably get me by for now!