Water Droplets in Compressed Air
Water Droplets in Compressed Air
(OP)
I have a production room that uses compressed air for blowoff of parts. Since this is a critical operation, I've installed a membrane dryer, and 1 micron filtration. The air is dried and filtered, then regulated from 100 psig down to about 30 psig, with the resulting pressure dewpoint around -60F (verified by instrument). The air system is kept pressurized at all times.
I'm ocassionally getting reports of water droplets on the parts being blown off with the air, although I can't imagine how this would be possible. I have not been around to witness it when the reports come in. My only thought is that it could be some other contamination, like flux from copper joints. Does anyone have any ideas on what else can be checked?
---KenRad
I'm ocassionally getting reports of water droplets on the parts being blown off with the air, although I can't imagine how this would be possible. I have not been around to witness it when the reports come in. My only thought is that it could be some other contamination, like flux from copper joints. Does anyone have any ideas on what else can be checked?
---KenRad





RE: Water Droplets in Compressed Air
Piping systems for compressed air should be designed with the assumption that there is water in the lines. Air tanks should be placed near users that periodically use high flow in order to level the flow through the drier. If you have users that sometimes use air at a rate greater than the dryer capacity, you will get water in your pipes.
RE: Water Droplets in Compressed Air
RE: Water Droplets in Compressed Air
MintJulep - I hadn't thought of that. I'll have to see how they are using the air nozzles, and whether or not they cool to the room dewpoint.
Thanks!
---KenRad
RE: Water Droplets in Compressed Air
T1/T2 = (P1/P2)(1-k)/k
So, T2 = 293/((7.8/3.04)[sup](0.4/1.4)[sup]=223K or 49C. This is 56.2F. So, air is cooling down below the ADP. With -60f ADP, you will have few problems.
RE: Water Droplets in Compressed Air
RE: Water Droplets in Compressed Air