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Pesky water in my compressed air lines!!

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svtmikey

svtmikey

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Does anyone know how to get rid of water in your compressed air lines?
It is not normally a problem but when I use my blast cabinet for extended periods of time, I keep getting that "yucky" white mixture of water and oil that clogs everything up. I already have a water separator and automatic oiler on the output from my compressor, as well as an additional water separator at the input to the blast cabinent...but that doesn't seem to be enough.
Anyone have any further suggestions?

Thanks
 
Have you drained your compressor tank lately?

Is it possible that the tank has a build up of water in it?

Just a thought....
 
Mikey,

I have used a number of different systems through the years in an attempt to eliminate water from my blast air lines and paint air lines

Knowing that cool air retains less water than warm air, I started with two 50 ft. lengths of hose running down and back up the slope of my driveway. I used a water separator at the 50’ mark (at the bottom of the hill). The dump valve on the separator was cracked open to constantly bleed the water from the lines.

I also used a bleeding water separator immediately before the blast or paint gun. That worked pretty well.

Next I soldered up a serpentine tube (3 ft. X 5 ft.) made of ½ inch copper pipe and elbows. This was mounted to the side of a shelving rack and ambient air was blown over it with a pedestal fan. Warm air went in the top and almost ambient temperature air came out the bottom. I also used a bleeding separator at the bottom of the serpentine. That worked a little better than the air hose in the driveway.

I now use about 100 feet of ½ inch copper tubing spiral wrapped around a 5 gallon plastic bucket and placed inside the bottom of my garage refrigerator. Filtered, warm air goes in the top and 40-50 degree air comes out the bottom and into a bleeding separator. From there, I run the air through 100 feet of hose so that it is warmed some by the time it gets to the guns. It works fine.

By the way – For painting or blasting, DITCH the oiler and any hose that you have run oil through. If you have run oil through a hose, oil will ALWAYS bleed from it. It may not make too much difference in blasting but it WILL in painting. NEVER run oil through any hose that you paint with. For painting ALWAYS use an in-line gauze filter before the paint gun.

I no longer use an in-line oiler, but manually oil the tools before and during use.

Tim

PS: I painted this car in my driveway
 
Keeping gunk out of air lines is a constant struggle. Like Stinky said, be sure your tank is completely drained. I assume you’ve drained the separators as well? Are they large enough for the kind of flow you get with media blasting?

You mentioned you have an oiler in the system. Is it on a line dedicated exclusively to motor driven tools? You should never introduce oil into lines/hoses used for blasting, inflating or especially painting. If oil does get into them they should be replaced or solvent purged.

If you have any fixed lines in your system you need to be sure they have no places where water can pool. They should always have a slope to them and the lowest point needs a way to collect and drain the condensate (called “drip legs”).

Air systems for critical work like painting will have top quality filter/regulators and extreme protective measures such as refrigerated driers, membrane driers and desiccant driers. They’re effective but expensive.

When I use air line of questionable history I usually put a disposable filter in line just before the tool.


PC.
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Mikey,
I have been using a metal pipe water trap based on the diagram from TP Tools (pdf document) metal trap . Mine is based on the green diagram. The fittings and pipes and valves can be sourced from most hardware stores. This along with water traps will get rid of the moisture problems in your system. BTW, Harbor Freight sells a cheap automatic air tank water drain, it drains the tank every time the tanks pressure drops to zero. Hope this helps.
 
Hey Mikey

Check this link out.

https://www.hobartwelders.com/mboard/show...essor+air+drier

This descibes a simple water separater that works great. I had the same problem with my blasting cabnet and built one of these "Franz Separaters" and could not believe the results. It completely eliminated my moisture problems. But as Franz explains the dryer must be between the compressor and the tank. Cost is less than $20 bucks.

Dennis
 
A refrigerated dryer is the only way to go for moisture free air but they are rather spendy. The next best bet is a heat exchanger, water flowing thru it cools the air and the moisture thus codenses and is then removed via a bucket type trap that is activated via a float that rises as moisture accumulates in it.
 
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