Shop air plumbing questions

[67-ls1]

Hi,
I'm new to the forum and was hoping you guys could help me out.
I just bought an 80 gallon, 2 stage, 175 psi upright air compressor and want to plumb my shop. I have decided to use copper pipe.
My questions are:
- Where I rise up and then loop back down from the main run at each drop, can I reduce from 3/4" copper pipe to 1/2" copper pipe? The total length of 1/2" pipe in each drop leg would be approx. 5'. The drop would be straight with only a tee where a tool could connect above the water trap section. I plan on regulating the 175 psi near the compressor outlet to approx 100 psi (adjustable).
- What do you guys use for drain valves at the bottom of each drop leg?
- Where I have connections for tools, should I use cast bronze fittings with mounting ears or just use a copper tee and strap it to the wall?
- What do you recommend for quick couplers for the tools? I have had ones in the past that leaked pretty bad if the hose so much as drooped under its own weight. There has to be a brand/model that won't do this.
Thanks in advance for your help and suggestions. I only want to have to do this once.
Dennis

 

[67-ls1]

So, I browsed the thread that showed all the shop air systems and it answered a couple questions and raised another.
My new compressor is 2 stage and has a finned pipe between the 2 stages and an approx 12" x 18" radiator style heat exchanger between the second stage and the tank, air cooled by the flywheel/fan on the 620 RPM pump.
Do I really need to make up a copper pipe array to cool the air more?
My first tool connection point would be approx 15' away and the blast cabinet on the end of the run would be approx 40' away.
Thanks,
Dennis

 

[383 240z]

I have 3/4" feeding 1/2" drops works fine in my shop.

1/2" ball valves at the bottomed each leg

I would guess the cast fittings with the ears would be stronger but I've had the standard straps for years. Just anchor them securely.

All quick connects will leak at some point. Milton makes my favorite ones. They seem to last longer then the rest.

 

[600SL]

Hi,
I'm new to the forum and was hoping you guys could help me out.
I just bought an 80 gallon, 2 stage, 175 psi upright air compressor and want to plumb my shop. I have decided to use copper pipe.
My questions are:
- Where I rise up and then loop back down from the main run at each drop, can I reduce from 3/4" copper pipe to 1/2" copper pipe? The total length of 1/2" pipe in each drop leg would be approx. 5'. The drop would be straight with only a tee where a tool could connect above the water trap section. I plan on regulating the 175 psi near the compressor outlet to approx 100 psi (adjustable).
- What do you guys use for drain valves at the bottom of each drop leg?
- Where I have connections for tools, should I use cast bronze fittings with mounting ears or just use a copper tee and strap it to the wall?
- What do you recommend for quick couplers for the tools? I have had ones in the past that leaked pretty bad if the hose so much as drooped under its own weight. There has to be a brand/model that won't do this.
Thanks in advance for your help and suggestions. I only want to have to do this once.
Dennis

Sound like your on your way to an excellent system.

3/4" to 1/2" downs would be excellent.

I would probably swet a male adapter to the copper pipe to install a pipe threaded on ball valve. Just easier for replacement. Also do not use any valves from Home Depot or Lowes. Get those from McMaster-Carr.

I'm a fan of the brass fittings with the mounting ears but I get over **** on those things.

Best couplers are Pervost They do not leak at all. But very expensive. I have been using them for over a year now and its the first time I can walk into my shop a week later turn the compressor on and not have it cycle. My Miltons would start hissing in about 6 months of use. http://www.mcmaster.com/#9585k18/=12ffs0q

As far as do you need an inter cooler after your inter cooler. You already have the ultimate system with that intercooler installed on the compressor. Most people don't even have that and just hook a hose from the compressor to the pipe system and don't bother with drops that go up first and then down. I only did that on my sand blaster and Eco Tireflator outlet. If what you have doesn't work you will really need to get a refrigerated moisture remover.

See my black pipe project: http://www.garagejournal.com/forum/showthread.php?t=275190

 

[matt_i]

Personally, I would adjust the pressure switch down to around 110-120psi if you are only intending to use 100psi on the header system. In my mind it improves the compressor life. If you clamp/amp the motor its working very hard, nearly FLA (full load amperage) just before the pressure switch cuts things off. Consequently, the pump is also working mechanically hardest against the back pressure and is generating the max heat per compression stroke.

My thoughts on ball valves are to use Nibco full port, threaded ends. While I realize there are ball valves that one can sweat solder, I think you get a better valve that doesn't have to withstand 900F. Use that on main, and use that right in back of each quick connect. It takes 1 more second of your life to throw the valve-arm. And, the valve is 100x better at sealing than a female QC.

Interestingly, I put my blast cabinet right next to the air compressor. This was to avoid losses in the piping. Not saying that's right or wrong. I do not have issues with moisture or any clumping of the glass beads.

I think with the run of "cold metal" pipe, especially copper, you will be OK. Also, with "teeing up" your drops, that also enforces keeping condensed water in the header. A slight taper toward the drip leg would be great. You could also go up to a larger header to 1" cu pipe (although $+). May not be required but would help lower the velocity in the pipe which gives more time to cool plus less re-entraining the condensed water due to high velocity.

 

[ABADWILLYS]

- What do you guys use for drain valves at the bottom of each drop leg?

I used air blow guns at the bottom of my drops, no bending over flipping a ball valve, just orient the handle outwards and you can just tap it with your foot, i thought i had a pic but cant find it, and actually i think i got the idea off this site!

 

[67-ls1]

Thanks for the replies and ideas. I'll try to post pics when I'm done.

 

[Falcon67]

>What do you guys use for drain valves at the bottom of each drop leg?

I use a gate valve above the hose connection and one below the connection for drainage. None of my hose connections are "hot" unless they are in use. Shut offs closed after each use.

Typical drop

 

[Jeff Ivers]

The general rule of thumb I have followed for years is at least 25 feet of pipe or hose after the tank and before a water separator to allow the air to cool enough to lose the water - particularly important for painting.

 

[csp]

I used air blow guns at the bottom of my drops, no bending over flipping a ball valve, just orient the handle outwards and you can just tap it with your foot

Why do your drops go so far down?

 

[67-ls1]

The general rule of thumb I have followed for years is at least 25 feet of pipe or hose after the tank and before a water separator to allow the air to cool enough to lose the water - particularly important for painting.

Is the 25' pipe rule as important given I have cooling between stages and between pump output/tank input? I will have approx. 15' of 3/4" copper between the tank and where I plan to mount the regulator/filter combo. I could go up/down or back/forth to add more pipe if it's super important.
I do not plan on painting at this time but if I ever did it would be from the far end of the line which is another 35-40' of 3/4" copper.

 

[CNGsaves]

OP . . . why in world would you regulate down to low pressure right after compressor ?? That is waste of 175 psi 2 stage compressor.

Rule of thumb is keep Airline System at same pressure as compressor.

Add regulator at drops to reduce pressure.

 

[brownbagg]

i was going to plumb my shop, but black iron not cheap, so i just hooked a reel to the side of the compressor and drag a hose around the shop. couple hundred dollars cheaper

 

[Brad Beam]

Rule number one. Use sun baked pvc

 

[ZRX61]

Why do your drops go so far down?

So he can tap it with his foot

 

[K'ledgeBldr]

The "best" plumbed system is a loop-
You mentioned blast cabinet at "end of run"

 

[Ironcrow]

Best couplers are Pervost

I think I'm sporting wood.

They make a coupler set that incorporates a wall mount bracket and a drain valve too.

 

[Stuart in MN]

Rule number one. Use sun baked pvc

There's always one in every crowd. PVC jokes stopped being funny a long, long time ago.

 

[4 FN 27]

3/4 main to 1/2 drop should be fine. I would loop the room however.

Instead of doing a drain leg at each drop come out of your main going vertical for an inch or 2 and then come down the wall. You will also need to put a drain leg somewhere. I prefer 2, one in each corner of the looped room.

We have a 110,000 square foot shop with looped 2 Inch Mains dropping either 1 inch, 3/4 or 1/2 depending upon a machines CFM requirements. We also have drain legs throughout the plant. All Copper. We had an energy audit last year and our power company said we have one of the tightest well maintain systems they have evaluated.

Here is a photo of what I am talking about. Drain Leg is on the left and the a supply drop is on the right. Sorry for the blurry picture, I zoomed in on an existing pic.

It is common practice to have a compressor at 175 psi and regulate your system down. This is more important in a factory where having to many fingers on the regulators can be dangerous. 2 weeks ago we had a glass FRL blow on a spotwelded. Fortunately it had a metal shield around it contained the glass. Our compressors run at 125 PSI and the plant is regulated to 105 psi.

At home my 2 stage is at 175 psi and regulated down to 110 psi. If I need more than that I can bypass the regulator and get to the full 175 psi.

Put some pics up of your progress.

Here is my install. Added in a couple of legs so I can add a dryer in the future.

 

[Dragfluid]

Rule number one. Use sun baked pvc

Only took 14 posts to get to this?
Ewe're an evil SOB.

 

[4AudiQ]

Here is what I use:
http://www.amazon.com/gp/product/B00CD8FHQY/?tag=atomicindus08-20
They do not leak.

 

[Moose97]

There's always one in every crowd. PVC jokes stopped being funny a long, long time ago.

Really? the second I saw the title of the post I saw a pvc joke coming?!?!?!?

 

[Jeff Ivers]

Is the 25' pipe rule as important given I have cooling between stages and between pump output/tank input? I will have approx. 15' of 3/4" copper between the tank and where I plan to mount the regulator/filter combo. I could go up/down or back/forth to add more pipe if it's super important.
I do not plan on painting at this time but if I ever did it would be from the far end of the line which is another 35-40' of 3/4" copper.

I am not familiar with the type of cooling you describe between the pump and the tank. However, I have doubts that it will be enough to drop the air temp back to room temperature. Perhaps you could use an infrared temperature gun to test the temp of the pipe where it goes into the tank. If that temp is above room temperature, then I think you want additional pipe to provide cooling before your water separator. My setup is tank - ball shutoff valve - pressure regulator (I regulate lines to about 100 psi) - oil separator - 30 feet of pipe - water separator - quick connect - 25 foot hose - tool.When painting, I use an additional filter and pressure regulator just before my paint gun. Other setups may work, I am mainly trying to alert you to consider if you will be running a paint gun and plan accordingly.

 

[67-ls1]

The "best" plumbed system is a loop-
You mentioned blast cabinet at "end of run"

Yeah, I would like to loop the room but it's 60 x 25 so it's not in the budget right now. All the shutoff valves, quick connects, fittings, etc, add up. For now I am going down one wall from the compressor about 45 feet.
Although as I put the system together I can plan to add the other portion of the loop as I can afford it. Thanks for the tip.

 

[67-ls1]

I do have the risers off the main line in the plans and drains below each connection point and at the end of the main line.

 

[67-ls1]

I am not familiar with the type of cooling you describe between the pump and the tank. However, I have doubts that it will be enough to drop the air temp back to room temperature. Perhaps you could use an infrared temperature gun to test the temp of the pipe where it goes into the tank. If that temp is above room temperature, then I think you want additional pipe to provide cooling before your water separator. My setup is tank - ball shutoff valve - pressure regulator (I regulate lines to about 100 psi) - oil separator - 30 feet of pipe - water separator - quick connect - 25 foot hose - tool.When painting, I use an additional filter and pressure regulator just before my paint gun. Other setups may work, I am mainly trying to alert you to consider if you will be running a paint gun and plan accordingly.

The aftercooler is pretty common. It looks like a radiator but it is air-to-air instead of water-to-air. The pump pulley/fan pulls air across it.
I will check the temp at the inlet to the tank with my inferred gun once I get the system done.
I will probably regulate down some on the main line and then further where needed at specific equipment.