Copper pipe for air system

[Nozzle]

What is the pressure capability of Copper pipe work? I have a compressor, (max pressure is 8bar) and I'm considering 22mm pipework with a mixture of compression and solder ring fittings to distribute it around the garage to some PCL sockets.

My query is what is the pressure rating of standard plumbers copper pipe and fittings? Using mild steel pipe and elbows is an option, but copper, though more expensive, is more friendly with moist air.

Nozzle

 

[45yearsagasman]

Check this outhttp://www.copper.org/publications/pub_list/pdf/copper_tube_handbook.pdf

 

[Nozzle]

Thanks for the link - I did see that one before and having noticed it was American I didn't look much further... not because the pipe work is imperial and the pressures in PSI (easy enough to convert/approximate) but there is a mention of different types of pipes, K, L & M. These do not seem to be options the man on the street has when he goes to a shop in the UK to buy pipe. I have the choice 15, 22 or 28mm in whatever hardness they have on the shelf. I think the fittings are the weak spot, so can compression fittings handle 8bar +a margin for over pressure/sudden pressurisation? I'll go solder ring where possible.

Nozzle

 

[GavThePlumber]

8 bar is nothing for soldered copper joints, i have tested copper to 20 bar, held for over 24 hours with no problem.

I have a 10 bar 100l compressor in my garage, run on 15mm copper, with 10mm air lines, which is good enough to get over 900nm of of my impact gun (according to manufacturer)

22mm is a lot unless you have many lines in use at the same time or big shot blast cabinets, what are you running?

 

[GavThePlumber]

You can always test this sort of stuff yourself for not a lot of money, buy one of these from TS..

http://www.toolstation.com/shop/Plumbing/Testing+Reporting/Testing+Pump+40+Bar/d20/sd2752/p36395

and test to twice the working pressure, that would show up any cocked up joints and avoid a mass depletion of air, which could be dangerous if you haven't cliped the pipe work in.

 

[doitall]

I though you had to have manipulative fittings

 

[Steelmasons]

If a fitting were to fail @ 8 bar (air as the medium) it would act like a bullet , when strength testing commercial gas procedures have to be put in place , be careful.

 

[GavThePlumber]

If it is clipped every meter or less, it won't go any where and soldered joints are fine for home to medium business use, there is no thermal cycling, thus is in a less demanding place that a typical heating system.

Just my opinion though, has worked fine for me last 20 years.

 

[Nozzle]

My compressor only has a 50 litre receiver so the plan is to use 22mm (now purchased) all the way through as not only will there be a smaller pressure drop (my garage is about 30ft long so it wouldn't be too much anyway) but the network itself will add to my overall capacity. Though I've just done some fag packet calcs for the 21metres of 22mm pipe I just purchased and it's only 7 litres. humph. Still that's 15% more capacity, plus I might keep the pressure pot valved in which adds another 20-25 litres.

I'll be having a flexible connection from the compressor to the network so I shouldn't have any trouble with vibration work-hardening the copper. It is a dodgy direct drive compressor, I might splash out on a larger one, or second one if required.

Nozzle

 

[Norcon]

What is the pressure capability of Copper pipe work? I have a compressor, (max pressure is 8bar) and I'm considering 22mm pipework with a mixture of compression and solder ring fittings to distribute it around the garage to some PCL sockets.

My query is what is the pressure rating of standard plumbers copper pipe and fittings? Using mild steel pipe and elbows is an option, but copper, though more expensive, is more friendly with moist air.

Nozzle

I did my home workshop years ago with 30m of Blue MDPE x 25mm. Its rated for 12 bar!
Compression fittings only!
Refrigeration copper can withstand the most pressure! I've put that stuff to 30 bar with nitrogen.
No pishfits on that one.

Also did our larger commercial workshop with 100m x black mdpe for an airline!