| Author |
Message |
Chris333
Samba Member
Joined: July 30, 2017
Posts: 656
Location: Ohio
|
 Posted: Wed Sep 06, 2017 8:12 pm Post subject: Compressor heat questions |
 |
|
Sorry to just ask here, but figured you guys would have more info than me. I just got a Campbell Hausfeld 60 gallon 2 cylinder air compressor 220V 3.2 hp. Not sure of the year because it is yellow and when I search all their stuff is blue. But the PO said it only had about 2 hours run time on it and the price was right... free. The thing looks brand new.
I used it all day with a siphon sandblaster. It worked great and never lost air, but as you can guess it ran a lot of the time. I'd guess the blasting is the most I would ever ask of it.
Should I worry that the pump and tank gets hot after running a while? I don't want to ruin the thing. It didn't shut down at all. The only reset I see is on the motor. Maybe I'm just being worried.
|
|
| Back to top |
|
 |
CiderGuy
Samba Member
Joined: December 23, 2013
Posts: 1351
Location: Bucks County, Pa
|
| Posted: Wed Sep 06, 2017 10:49 pm Post subject: Re: Compressor heat questions |
|
|
I have the blue one....... I don't think these compressors were meant to run non stop. I have a 60 gallon slave tank, 120 gallons of air. It helps.
_________________
----------------------
Cars Currently Owned:
1970 Karmann Ghia Coupe
1973 Karmann Ghia Coupe - Project car for sale
1970 Karmann Ghia Convertible (Body off restoration)
Timing is everything |
|
| Back to top |
|
|
Chris333
Samba Member
Joined: July 30, 2017
Posts: 656
Location: Ohio
|
| Posted: Wed Sep 06, 2017 11:20 pm Post subject: Re: Compressor heat questions |
|
|
| I'll keep my eye on Craigslist for another tank. |
|
| Back to top |
|
|
Wayne S. Johnson
Samba Member
Joined: April 12, 2006
Posts: 1265
Location: GILROY, CA
|
|
| Back to top |
|
|
Evil_Fiz
Samba Member
Joined: May 06, 2011
Posts: 1045
Location: Jacksonville, FL
|
| Posted: Thu Sep 07, 2017 5:39 am Post subject: Re: Compressor heat questions |
|
|
| Chris333 wrote: |
| ...I used it all day with a siphon sandblaster. It worked great and never lost air, but as you can guess it ran a lot of the time. I'd guess the blasting is the most I would ever ask of it. |
I will second CiderGuy's comments about run-time and add that your compressor looks a lot like, and has identical specs to, mine which is a re-branded PUMA sold by Northern Tools under their house brand "North Star." Mine has a 70% duty cycle so I imagine yours in in the same ballpark.
As has been stated already, the cooler you keep the pump and motor the longer you compressor will serve you well. Don't forget to drain the tank regularly, change the oil at the scheduled interval, and make sure you use the oil recommended by the manufacturer.
Another thing to consider is moisture removal. The longer the compressor runs, the hotter the air charge will get which will lead to ever increasing amounts of water condensing in the tank and eventually working its way to the tools attached at the end of the line. One thing you can do to minimize air temperature is build or buy an aftercooler to go between the pump and the tank. This will reduce air temperature considerably (from ~290 down to room temperature + ~10*) and will help the compressor run cooler as well. The other cooling option is to run a 50' zig-zag length of pipe after the tank to cool the air before it reaches your tools. Both of these solutions will require a water separator post-cooling to remove the condensed water.
Here is the aftercooler I built using a transmission oil cooler and a 220V/1150CFM fan. I also plan on building a shroud and fan setup for the pump and motor.
You may also want to take a look at this thread "Sandblasting - Harbor Freight Compressor" for more compressor discussion.
...we're all in this together.
Emil
_________________
It's not just about what's interesting. It's also about what's helpful, and it's helpful even if it helps just one other guy working on a Ghia.
kiwighia68
See my build on TheSamba at:
The K_R_A_K_E_N_N : a 70 Ghia Convertible reinterpreted |
|
| Back to top |
|
|
Chris333
Samba Member
Joined: July 30, 2017
Posts: 656
Location: Ohio
|
| Posted: Thu Sep 07, 2017 9:30 am Post subject: Re: Compressor heat questions |
|
|
How do you know when the compressor is hot enough to cause harm?
I mean if I could just hook up something to tell me I'd just stop working when it gets hot.
I like the oil cooler idea. |
|
| Back to top |
|
|
Evil_Fiz
Samba Member
Joined: May 06, 2011
Posts: 1045
Location: Jacksonville, FL
|
| Posted: Thu Sep 07, 2017 10:48 am Post subject: Re: Compressor heat questions |
|
|
| Chris333 wrote: |
| How do you know when the compressor is hot enough to cause harm? |
The compressor outlet temperature can and will climb to around 300*F; the heads will be slightly cooler. Dissipating as much of that heat as possible will protect the valves, which are the most likely point of failure. The problem is not reaching excessive operating temperature but rather reaching maximum operating temperature for extended periods beyond those the system was designed for. A 70% duty cycle means the system should run for 7min. and rest for 3 min. The problem we face is that most tools will consume enough air to make the compressor fire before the full rest period has been reached. Your compressor should take about 7.5 minutes to fill from empty and about 3:20 to fill from 110 PSI to 135 PSI. Writing this response just gave me the idea that using an Arduino to control run time would solve the duty cycle problems. It could be programmed to cut power after 7 min. and keep it off for 3.5 min. That would force adherence to the duty cycle rating. Look up Hannah's Bug on YouTube. She built an Arduino based system to control several compressors she chained together. Here is the link to the episode: https://www.youtube.com/watch?v=YGYgQO5TFto
In one of the responses to the thread I mentioned above I added links to one project where the owner uses muffin fans to cool the heads. The benefit of having a fan continue to cool the heads and motor after the compressor has stopped working is that the unit will take longer to climb to max temperature when it fires up again.
I don't want to hijack your thread but if you want details on the aftercooler I will provide them. I can supply part numbers and a Sketchup drawing of the bracket I built to hold it.
Cheers.
_________________
It's not just about what's interesting. It's also about what's helpful, and it's helpful even if it helps just one other guy working on a Ghia.
kiwighia68
See my build on TheSamba at:
The K_R_A_K_E_N_N : a 70 Ghia Convertible reinterpreted |
|
| Back to top |
|
|
theKbStockpiler
Samba Member
Joined: July 07, 2012
Posts: 2316
Location: Rust Belt
|
| Posted: Thu Sep 07, 2017 2:03 pm Post subject: Re: Compressor heat questions |
|
|
I run my own moderately good quality compressor all out for approximately 45 minutes at a time or unlit I need a break. I change the oil before and after a big blasting project (4 hours tops). If the ambient temp is over 78 I put a small fan on it and keep the sun light off of it.
_________________
My beetle is not competing with your beetle. I have the yellow beetle in my town. There is a red one, a green one ......
Use all safety devices including a mask. |
|
| Back to top |
|
|
Chris333
Samba Member
Joined: July 30, 2017
Posts: 656
Location: Ohio
|
| Posted: Thu Sep 07, 2017 2:58 pm Post subject: Re: Compressor heat questions |
|
|
I think I'll be OK knowing the 7 min on and 3 min off rule. I had no idea what that should be before this. Also I was running with out a gauge fully open. Today I got a gauge and blasted at 50psi, that helped a lot.
I have to blast under the package tray and in the engine bay. After that just small parts one at a time. |
|
| Back to top |
|
|
theKbStockpiler
Samba Member
Joined: July 07, 2012
Posts: 2316
Location: Rust Belt
|
| Posted: Thu Sep 07, 2017 3:33 pm Post subject: Re: Compressor heat questions |
|
|
Are you serious with the Duty Cycle for a compressor?
_________________
My beetle is not competing with your beetle. I have the yellow beetle in my town. There is a red one, a green one ......
Use all safety devices including a mask. |
|
| Back to top |
|
|
Evil_Fiz
Samba Member
Joined: May 06, 2011
Posts: 1045
Location: Jacksonville, FL
|
| Posted: Fri Sep 08, 2017 9:01 am Post subject: Re: Compressor heat questions |
|
|
| theKbStockpiler wrote: |
| Are you serious with the Duty Cycle for a compressor? |
I am, an stop calling me serious
Your query prompted me to confirm my compressors specs. At one point my compressor was rated for a 70% duty cycle but it it currently rated for a 60% duty cycle on the Northern Tool web site. Could you kindly elaborate on what you are referencing with your comment above. Are you questioning the duty cycle itself or my interpretation of how the duty cycle is calculated?
_________________
It's not just about what's interesting. It's also about what's helpful, and it's helpful even if it helps just one other guy working on a Ghia.
kiwighia68
See my build on TheSamba at:
The K_R_A_K_E_N_N : a 70 Ghia Convertible reinterpreted |
|
| Back to top |
|
|
theKbStockpiler
Samba Member
Joined: July 07, 2012
Posts: 2316
Location: Rust Belt
|
| Posted: Fri Sep 08, 2017 1:56 pm Post subject: Re: Compressor heat questions |
|
|
My best guess is it's a 2.7hp motor with a oversized capacitor and drive pulley. I have my 5hp wired for 110v and it still can be run continuously.
_________________
My beetle is not competing with your beetle. I have the yellow beetle in my town. There is a red one, a green one ......
Use all safety devices including a mask. |
|
| Back to top |
|
|
theKbStockpiler
Samba Member
Joined: July 07, 2012
Posts: 2316
Location: Rust Belt
|
| Posted: Tue Sep 12, 2017 7:41 am Post subject: Re: Compressor heat questions |
|
|
The Husky brand 3.7hp 60 gallon compressor manual reads that the compressor has a duty cycle of 100 percent but to prolong it's life it is suggested that if it is run for 30 minutes continuously , to let it rest for 30 minutes. 
_________________
My beetle is not competing with your beetle. I have the yellow beetle in my town. There is a red one, a green one ......
Use all safety devices including a mask. |
|
| Back to top |
|
|
Chris333
Samba Member
Joined: July 30, 2017
Posts: 656
Location: Ohio
|
| Posted: Fri Sep 29, 2017 3:47 pm Post subject: Re: Compressor heat questions |
|
|
To bring this back up.
Every time I went to drain the bottom of the tank there was no air in it, but nothing came out. I figured it was nice and clean. It was a pain to get under there to drain it so I added a 90 bend and a 12" nipple with a ball valve.
Today saw there was a small puddle under it. Opened the valve and nothing at 130 psi  I saw my 90 had split and the water was leaking there very slowly.
So I drained all the air. Took the nipple and 90 off. Stuck an allen wrench up into the hole and about a gallon of water flooded out. At the end it was a nice thick yellow oil sludge, great. Made a mess. 
Got a new 90 and now the valve works, blows out the oily sludge mostly now.
Must of been this thing was never drained. I did change the oil in it. That made a mess as well so I added a long nipple to the oil drain. The way it was you could drain the oil without making a mess. 
Now I plan to add a condenser between the pump and tank. Gonna try to find a big automotive one cheap at the local scrap yard. |
|
| Back to top |
|
|
Busstom
Samba Member
Joined: November 23, 2014
Posts: 3841
Location: San Jose, CA
|
| Posted: Thu Oct 12, 2017 7:05 pm Post subject: Re: Compressor heat questions |
|
|
I guess I'm a compressor abuser...I've been beating the hell out of my 120 volt Campbell for at least 20 years. It's my 2nd Campbell....the first one is a 240 volt model, got it in '85...still runs in the back of my parents' garage. I beat the hell out of that one too when I was younger, sandblasting and you name it. I use a die grinder for many things, and that will consume like a sandblaster.
The way I look at it, rebuilding them is ridiculously easy, and parts are readily available. I've never paid mind to duty cycles on them, but on long runs I can damn near smell the paint burning on the heads, but oh well...I need air! 
Oh by the way, if you haven't noticed yet, if you open the drain cock with a lot of pressure, the outlet will freeze over with water if there's enough in it. So it'll keep melting, sputter, refreeze, etc. So sometimes, I'll drain the tank one night, then go out in the morning, and fire it up with the drain cock open, and it tends to blow a lot of the excess water out without freezing, because it doesn't develop the pressure that it would when it's full, and so it doesn't tend to freeze as much, or at all. Depends on time of year, where you live, etc. But with your upright, hopefully the outlet is right at the bottom, and you won't have drainage issues at all. |
|
| Back to top |
|
|
modok
Samba Member
Joined: October 30, 2009
Posts: 26785
Location: Colorado Springs
|
| Posted: Thu Oct 12, 2017 10:57 pm Post subject: Re: Compressor heat questions |
|
|
The working limits of a cast iron compressor pump are very similar to an engine. Yes you can run it all day, and the oil needs to be fresh, clean, and in a safe range of temp. It's functionally.... the same as a vw 
The electric motor??? not sure, but, I'd run er flat out, if it dies I guess it wasn't very good. |
|
| Back to top |
|
|
Bobnotch
Samba Member
Joined: July 06, 2003
Posts: 22410
Location: Kimball, Mi
|
| Posted: Fri Oct 13, 2017 8:09 am Post subject: Re: Compressor heat questions |
|
|
| Busstom wrote: |
I guess I'm a compressor abuser...I've been beating the hell out of my 120 volt Campbell for at least 20 years. It's my 2nd Campbell....the first one is a 240 volt model, got it in '85...still runs in the back of my parents' garage. I beat the hell out of that one too when I was younger, sandblasting and you name it. I use a die grinder for many things, and that will consume like a sandblaster.
The way I look at it, rebuilding them is ridiculously easy, and parts are readily available. I've never paid mind to duty cycles on them, but on long runs I can damn near smell the paint burning on the heads, but oh well...I need air!
Oh by the way, if you haven't noticed yet, if you open the drain cock with a lot of pressure, the outlet will freeze over with water if there's enough in it. So it'll keep melting, sputter, refreeze, etc. So sometimes, I'll drain the tank one night, then go out in the morning, and fire it up with the drain cock open, and it tends to blow a lot of the excess water out without freezing, because it doesn't develop the pressure that it would when it's full, and so it doesn't tend to freeze as much, or at all. Depends on time of year, where you live, etc. But with your upright, hopefully the outlet is right at the bottom, and you won't have drainage issues at all. |
I'm in the same boat, in that I'm a compressor abuser. I've got a Campbell Hausfeld 7.5 hp V4 80 gallon Cast Iron series stand up compressor, that I've been using off and on since I bought it new in 1998. When I use it for sandblasting, it's running constantly for 30 to 45 minutes before getting a short break (while I'm refilling the blaster, 50 lbs at a time), then it's back to it again for 30 to 45 minutes. I'll run 7 to 10 bags and not think twice about it. To me, sandblasting is just a semi controlled air leak.
A die grinder, long board sander, DA sander, sandblaster, they're all air tools that are controlled air leaks that use large volumes of air. Impacts and air ratchets are basically short blasts, and a spray gun also falls into that category too. I say that, as the compressor might cycle once or twice while being used.
In almost 20 years that I've had it, I've had the electric motor serviced twice (bearings), changed the oil a few times, and even moved it out of the garage into it's own dedicated room (mainly to control dust, but also so I can hear my garage stereo while it's running). I've definitely gotten my money's worth out of it, and it doesn't owe me a dime. If it needs anything, I'll replace it, or have it fixed. I bought as the last compressor that I need to buy, and I use the hell out of it.
_________________
Bob 65 Notch S with Sunroof
71 Notch ...aka Krunchy; build pics here;
http://www.thesamba.com/vw/forum/viewtopic.php?t=249390 -been busy working
64 T-34 Ghia...aka Wolfie, under construction... http://www.thesamba.com/vw/forum/viewtopic.php?t=412120
| Tram wrote: |
| "Friends are God's way of apologizing for relatives." |
| Tram wrote: |
| People keep confusing "restored" and "restroyed". |
|
|
| Back to top |
|
|
bobinphx
Samba Member
Joined: August 14, 2016
Posts: 165
|
| Posted: Thu Nov 02, 2017 9:50 pm Post subject: Re: Compressor heat questions |
|
|
| a buddy of mine has a 10 year or so old husky compressor. Since we live in PHX, heat is an issue. He put a couple of 8 or 10 inch High volume 110v computer server cabinet fans on the dual cylinders. The fans run with the compressor running or he can turn them on and leave them on. He had an accident where the compressor was turned on and overnight a hose sprung a leak that kept the pressure in the tank at 90 psi. That compressor ran 100 percent for 16 hours as near as we can tell. Bottom line, we changed the oil and that compressor still runs fine. I believe that the fans saved the compressor. |
|
| Back to top |
|
|
Chris333
Samba Member
Joined: July 30, 2017
Posts: 656
Location: Ohio
|
| Posted: Mon Jun 18, 2018 12:58 am Post subject: Re: Compressor heat questions |
|
|
To bring this back up.
At work we have 4 old air dryers that are not in use. The surface are of the cooling "radiator" is about 24x24" so it is pretty beefy. And I would like to put it between my pump and tank.
The compressor line is about 1/2" copper.
The dryer inlet and outlets are about 1.75" dia copper.
I'm sure I can find whatever pipe reducers I need to plumb it up, but will I have problems going from 1/2 line to a larger line, into the grid, out a larger line and then back to a 1/2" line?
It is scrap so they gave it to me and it has a large fan built into it. I'd like to make it work and save a few bucks. |
|
| Back to top |
|
|
theKbStockpiler
Samba Member
Joined: July 07, 2012
Posts: 2316
Location: Rust Belt
|
| Posted: Mon Jun 18, 2018 1:22 pm Post subject: Re: Compressor heat questions |
|
|
I don't know if you came across this info but you have to source hardened tube because the soft stuff has a low temperature rating of about 150 degrees.
_________________
My beetle is not competing with your beetle. I have the yellow beetle in my town. There is a red one, a green one ......
Use all safety devices including a mask. |
|
| Back to top |
|
|
|
