Today I started changing my original air filtering system to a Tuxing 30MPA water/oil separator and desiccant set up. My compressor is a Yong Heng but the issue I found can affect fittings on any tank, compressor or air hoses.
On the Yong Heng, there is a black filter housing on the output line coming from the compressor. This housing, like many out there, is made of thick aluminum. Inside there is a filter that will catch oil vapor from the pump. When I removed the fitting from the output side of the filter, I found that it was pretty corroded.
A little background on my setup will let you know this was not from lack of maintenance. I have had my compressor set up for maybe 4 or 5 years. When I first got it, I upgraded the water cooling system, added a desiccant packed intake tube and added a desiccant/ molecular sieve filter after the oil filter. I use the compressor to charge a 4500 psi tank so it doesn't get used until the tank gets to 3000 PSI.
Before each use, I inspect the desiccant media and replace it as necessary. Same goes with the oil filter and molecular sieve. After the compressor cylinder cools (which is pretty fast as a fan helps it out), I shut both high and low bleed valves. The output line is connected to the tank and the intake water separator is plugged so I have a closed system with no chance of moisture getting in. Due to this, I believe the corrosion is dissimilar metal corrosion. As I said before, all the filter housings I have handled are aluminum and the fittings are all steel.
I believe that the Chinese plating on the fitting is sub standard and that the filter housing was anodized before the holes were drilled. This leaves bare aluminum contacting a poorly plated steel fitting which is going to corrode if any moisture is evident.
I have just checked all my fittings and have added yellow teflon tape to them until I can find stainless steel replacements. 4500 pounds of air is nothing to treat lightly. Stay safe out there.
On the Yong Heng, there is a black filter housing on the output line coming from the compressor. This housing, like many out there, is made of thick aluminum. Inside there is a filter that will catch oil vapor from the pump. When I removed the fitting from the output side of the filter, I found that it was pretty corroded.
A little background on my setup will let you know this was not from lack of maintenance. I have had my compressor set up for maybe 4 or 5 years. When I first got it, I upgraded the water cooling system, added a desiccant packed intake tube and added a desiccant/ molecular sieve filter after the oil filter. I use the compressor to charge a 4500 psi tank so it doesn't get used until the tank gets to 3000 PSI.
Before each use, I inspect the desiccant media and replace it as necessary. Same goes with the oil filter and molecular sieve. After the compressor cylinder cools (which is pretty fast as a fan helps it out), I shut both high and low bleed valves. The output line is connected to the tank and the intake water separator is plugged so I have a closed system with no chance of moisture getting in. Due to this, I believe the corrosion is dissimilar metal corrosion. As I said before, all the filter housings I have handled are aluminum and the fittings are all steel.
I believe that the Chinese plating on the fitting is sub standard and that the filter housing was anodized before the holes were drilled. This leaves bare aluminum contacting a poorly plated steel fitting which is going to corrode if any moisture is evident.
I have just checked all my fittings and have added yellow teflon tape to them until I can find stainless steel replacements. 4500 pounds of air is nothing to treat lightly. Stay safe out there.
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