Is 1/2" enough? - Pirate4x4.Com : 4x4 and Off-Road Forum
 
Pirate4x4.Com : 4x4 and Off-Road Forum  

Go Back   Pirate4x4.Com : 4x4 and Off-Road Forum > General Tech > Shop and Tools
Notices

Reply
 
Share Thread Tools Display Modes
Old 01-23-2011, 01:46 PM   #1 (permalink)
Registered User
 
Join Date: Feb 2000
Member # 10
Location: Magna, UT
Posts: 1,721
Is 1/2" enough?

For shop air plumbing--I have some 1/2" copper pipe and fittings already, I'm wondering if it's large enough that I won't see a pressure drop at the other end. It seems like most people are using larger diameter stuff.

It'd be going in a 26x32 building, so the furthest distance from the compressor would be maybe 75'-ish.
__________________
Carl Whitmore
I Lean is offline   Reply With Quote
Old 01-23-2011, 01:59 PM   #2 (permalink)
Rock God
 
Wyoming9's Avatar
 
Join Date: May 2008
Member # 113418
Location: New Tripoli Pa
Posts: 1,704
Red face

Depends more on your CFM requirements Also how much your compressor puts out.

If you are sand blasting in a big way you might want larger pipe.

Then again you are most likely using 1/4 or at most 3/8 quick connect fittings

Bigger never hurt but it does take just that much longer for the compressor to recover.
Wyoming9 is offline   Reply With Quote
Sponsored Links
Old 01-23-2011, 02:02 PM   #3 (permalink)
Registered User
 
Shefron's Avatar
 
Join Date: Oct 2006
Member # 80692
Location: Charlotte, NC
Posts: 1,252
Quote:
Originally Posted by I Lean View Post
For shop air plumbing--I have some 1/2" copper pipe and fittings already, I'm wondering if it's large enough that I won't see a pressure drop at the other end. It seems like most people are using larger diameter stuff.

It'd be going in a 26x32 building, so the furthest distance from the compressor would be maybe 75'-ish.
I would use 3/4 or 1in to avoid pressure drop. I get some pressure drop when running air tools off a 25' hose reel.
Shefron is offline   Reply With Quote
Old 01-23-2011, 02:04 PM   #4 (permalink)
Wheeler
 
solarpower's Avatar
 
Join Date: May 2005
Member # 47722
Location: Toledo O-H-I-O
Posts: 258
copper seems like pretty fancy stuff for air lines.

1/2 should be fine...but remember that using larger pipe adds to the volume of air over all. Your pressure will be the same no matter what size line you use. If it's 120 PSI at the tank..it will be 120 PSI in the lines unless you use a pressure regulator. but like they said it's all about the compressor recovering.

I would save the copper for a water line.
__________________
Professional Driver. Closed course.

Last edited by solarpower; 01-23-2011 at 02:05 PM.
solarpower is offline   Reply With Quote
Old 01-23-2011, 02:06 PM   #5 (permalink)
Registered User
 
Join Date: Feb 2000
Member # 10
Location: Magna, UT
Posts: 1,721
Quote:
Originally Posted by Wyoming9 View Post
Depends more on your CFM requirements Also how much your compressor puts out.

If you are sand blasting in a big way you might want larger pipe.

Then again you are most likely using 1/4 or at most 3/8 quick connect fittings

Bigger never hurt but it does take just that much longer for the compressor to recover.
No blaster, just normal air tools and a plasma cutter. Probably my greatest CFM user would be stupid little die grinders, my compressor gets it's ass handed to it by those.

It's a 60gallon Husky single-stage, claimed output 10.3CFM @ 90psi.

Quote:
Originally Posted by Shefron View Post
I would use 3/4 or 1in to avoid pressure drop. I get some pressure drop when running air tools off a 25' hose reel.

Me too, which is why I ask. I think my hose reel has 3/8" hose, plus the swivel fitting and whatever--so I know the 1/2" pipe won't drop as much as that does, but over a longer distance.

Any engineeer types know how to figure exactly what pressure drop I'd see over a given distance?
__________________
Carl Whitmore
I Lean is offline   Reply With Quote
Old 01-23-2011, 02:08 PM   #6 (permalink)
Registered User
 
trkklr77's Avatar
 
Join Date: Apr 2004
Member # 29016
Location: galt ca, because i wanted my own backyard
Posts: 6,032
1/2" is enough for me to crush 14bff pinion sleaves over 100' away from the compressor.
trkklr77 is offline   Reply With Quote
Old 01-23-2011, 02:08 PM   #7 (permalink)
Registered User
 
Join Date: Feb 2000
Member # 10
Location: Magna, UT
Posts: 1,721
Quote:
Originally Posted by solarpower View Post
copper seems like pretty fancy stuff for air lines.

1/2 should be fine...but remember that using larger pipe adds to the volume of air over all. Your pressure will be the same no matter what size line you use. If it's 120 PSI at the tank..it will be 120 PSI in the lines unless you use a pressure regulator. but like they said it's all about the compressor recovering.

I would save the copper for a water line.
I've been looking at this little stack of copper for about 9 years, so I feel fine with using it.
__________________
Carl Whitmore
I Lean is offline   Reply With Quote
Old 01-23-2011, 02:12 PM   #8 (permalink)
Registered User
 
Shefron's Avatar
 
Join Date: Oct 2006
Member # 80692
Location: Charlotte, NC
Posts: 1,252
Quote:
Originally Posted by I Lean View Post
No blaster, just normal air tools and a plasma cutter. Probably my greatest CFM user would be stupid little die grinders, my compressor gets it's ass handed to it by those.

It's a 60gallon Husky single-stage, claimed output 10.3CFM @ 90psi.




Me too, which is why I ask. I think my hose reel has 3/8" hose, plus the swivel fitting and whatever--so I know the 1/2" pipe won't drop as much as that does, but over a longer distance.

Any engineeer types know how to figure exactly what pressure drop I'd see over a given distance?
I would scrap the copper line for air like the other guys are saying and get some gav pipe. Not to bad for pricing overall and can be cut to length. Dont forget to put a slope in the pipe and maybe a drain at the end.

edit: One or two water seperators would be nice also

Last edited by Shefron; 01-23-2011 at 02:13 PM.
Shefron is offline   Reply With Quote
Old 01-23-2011, 06:39 PM   #9 (permalink)
Rock God
 
Join Date: Nov 2002
Member # 15076
Location: Indianapolis
Posts: 1,809
I just ran 1" copper for mine as I never really had decent pressure with the 1/2" black iron pipe I had installed previously. I did this when I changed the compressor out to an 80 gal. 2 stage. It runs up to 175psi at the tank but with the one inch and my regulator wide open I'm only getting about 130 psi static pressure at one of the 3/4 branch lines. So with that I'm thinking that you do lose some pressure in the system depending on your air line size. I can't explain it right now and don't really care enough to look it up either.

As far as galv. pipe goes. This is from the TP tools website.

"We do not recommend galvanized metal pipe, as galvanization can come off the inside of the pipe, clogging separators and regulators."
MQYJ is offline   Reply With Quote
Old 01-23-2011, 09:02 PM   #10 (permalink)
Zeus of the Sluice
 
Join Date: Feb 2002
Member # 9835
Location: Chicago
Posts: 4,231
http://www.gates.com/industrial/pres...043#calculator

The 1/2" copper will outflow any of your quick connect fittings.
ChiScouter is offline   Reply With Quote
Old 01-23-2011, 09:18 PM   #11 (permalink)
Rock God
 
Join Date: Feb 2009
Member # 130003
Location: Polk City, Iowa
Posts: 1,596
Some friends with a truck repair shop use 1/2" copper and have since 1962.
I'm guessing the copper will work just fine.
I think I would run it in a loop. All the way around and back to the compressor, I read that was the "best" way to do it, but don't remember the reason.
Weird thing about galv pipe, with air, it plugs up faster than black pipe with the condensation making rust. I REALLY have no idea why.
The new 1/2" aluminum tubing for air, claims to flow more than 1 1/2" black pipe. Also has really cool drop attachments, but it isn't cheap.
All that being said, I am starting to run 2" black around my shop, and will TRY to do it in a loop. To start it will just be like branches, but I will run it so it can be in a loop. The "drops" will start with a cross, drain only on the down port, and the "drop" will be off the top port of the cross, bushed down to 3/4" or 1" black pipe for the drop. Depends on what is available when I start buying drop stuff.
The air drop will also have a drain on it.
Drops every 10 feet will be plenty.
Harold Phipps is offline   Reply With Quote
Old 01-24-2011, 05:39 AM   #12 (permalink)
Registered User
 
Join Date: May 2001
Member # 4554
Location: Atlanta, Ga. USA Earth Sol etc.
Posts: 1,346
Send a message via AIM to bluesman2a
I run 3/4" main lines with 1/2" drops. All copper. The best of both worlds. Everything in red is 3/4". It runs off an 80 gallon 2-stage at 175 PSI, and I use it for standard air-tools, blasting, etc.

In a perfect world it would be looped as mentioned above, but this works quite well.



As mentioned above, make sure you plumb your drops so they can be drained and don't accumulate water. I did mine like this:
__________________
<blank>

Last edited by bluesman2a; 01-24-2011 at 05:42 AM.
bluesman2a is offline   Reply With Quote
Old 01-24-2011, 08:56 AM   #13 (permalink)
Registered User
 
Join Date: Feb 2000
Member # 10
Location: Magna, UT
Posts: 1,721
Thanks for the replies! ChiScouter, that calculator is exactly what I was looking for--but everything I found online wanted WAY more parameters that I didn't know/don't care about. It looks like I'll see less than a pound of pressure loss, which it completely acceptable.

If I don't have enough 1/2" to do the job, I like the idea of 3/4" runs with 1/2" drops. (if I have to buy anything....)
__________________
Carl Whitmore
I Lean is offline   Reply With Quote
Old 01-24-2011, 09:08 AM   #14 (permalink)
Registered User
 
Join Date: Oct 2001
Member # 7753
Location: Canada
Posts: 1,007
Either your gauge or your regulator is fucked. There is no friction loss at static. Even flowing, you can move a lot of air in 1" pipe or tube without any serious pressure drop.

Quote:
Originally Posted by MQYJ View Post
I just ran 1" copper for mine as I never really had decent pressure with the 1/2" black iron pipe I had installed previously. I did this when I changed the compressor out to an 80 gal. 2 stage. It runs up to 175psi at the tank but with the one inch and my regulator wide open I'm only getting about 130 psi static pressure at one of the 3/4 branch lines. So with that I'm thinking that you do lose some pressure in the system depending on your air line size. I can't explain it right now and don't really care enough to look it up either.

As far as galv. pipe goes. This is from the TP tools website.

"We do not recommend galvanized metal pipe, as galvanization can come off the inside of the pipe, clogging separators and regulators."
Slowzuki is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -7. The time now is 12:52 PM.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0 ©2011, Crawlability, Inc.