Treasure

[SKIPRAT]

Hi Gang
If you have seen my previous posts you will know i suffer from an incurable affliction
"PAKRAT SYNDROME" anyhow i was told about this lying neglected at the back of a dark damp garage and destined for the scrapman so went to look at it made Friends with it and it followed me home

well i have taken a before picture of my compressor project so i am now going to do a teardown to do a few general checks on its condition and then a rebuild and put it back to work for me. I know this forum is about model engines and as an aircompressor is a tool i thought it was worth a mention. If anyone is interested in the other machinery i have rescued i would love to tell them about it.

Cheers Paul

 

[vlmarshall]

Well, I'm interested. ;D
Your new compressor looks fairly complete too, although i don't see a pressure switch. I always rate the success of a "dive" by how LITTLE I have to spend on the treasure.

 

[SKIPRAT]

Hi Vernon
As for the pressure switch i think that went missing several years ago! the compressors original use was it was part of the refrigeration plant for a butchers coldroom most likely compressing freon or some thing like that did you notice the metering valves on the inlet and outlet going to take cylinder head off tomorrow and check condition of the reed valves and such like looking at it i think it is a twin cylinder model when it is rebuilt it will of course be fitted with pressure switch, unloading valve and the air tank will have safety valve, drain valve,and pressure gauge.the reason why it appeals to me is that it is not direct drive as i find them a bit too noisy for me. the cost of this dive was £00.00 that was a bargain i could not miss !!

Cheers Paul

 

[ozzie46]

If anyone is interested in the other machinery i have rescued i would love to tell them about it.

Cheers Paul
[/quote]

I'm interested too.


Ron

 

[vlmarshall]

Yes! I thought it might be an A/C compressor, it reminds me of a YORK compressor I've seen in automotive use, populr for it's usefulness in air compressor conversions.... just like you have here, I guess. ;D

the reason why it appeals to me is that it is not direct drive as i find them a bit too noisy for me. the cost of this dive was £00.00 that was a bargain i could not miss !!

Ha, I agree, the direct-drive compressors are unbearably loud.

 

[Stan]

Refrigeration compressors are not the best choice for an air compressor, but they do work, sort of. They depend on the final expansion of the refrigerant gas for cooling so you have to be careful and not overheat them. They are not designed for negative pressure on the suction side, and were designed to run with 15 - 30 PSI positive suction pressure. With 30 PSI on the suction you could probably get 160 PSI discharge pressure. With the suction sucking through a filter you will be hard pressed to get 100 PSI discharge.

I have used several all the way from household refrigerator units up to a large compressor driven by a 4 cylinder Perkins diesel and they all exhibited the same characteristics but your mileage may vary.

 

[SKIPRAT]

hi Stan
thanks for the info about positive pressure being needed on the suction side of a refrigeration compressor did not know that. also the info about the compressor relying on the expansion of the refrigerant gas to help with cooling that
explains the lack of cooling fins on the compressor body and probably the reason for expansion chamber on suction side and the metering valves on both suction and pressure sides, i can remember something about an experiment at technical college involving a copper can with some water under it and a small amount of ether in it by blowing on the ether with a drinking straw it evaporated causing the water under the can to freeze as far as i can remember this was due to latent heat. as for my compressor i don't want to squeeze what i can out of it just get compressed air in my workshop to run "Future Engine Builds" with it once again thanks Stan

Cheers Paul

 

[vlmarshall]

A bunch of guys I know use 'em for onboard vehicle air compressors... here's a few examples of similar setups.

http://jeep.off-road.com/jeep/article/articleDetail.jsp?id=261434

http://www.jedi.com/obiwan/jeep/yorkair.html