Safely Linking 2 x Compressors To Increase Air Supply For Spraying

[JonnyAlpha]

Do not use domestic water copper pipe & fittings for compressed air, they are not sufficiently pressure rated, remember the stored energy in compressed air systems can cause injury and damage.
You need to use copper pipe and fittings rated for 10 bar+ for compressed air, seriously, please don't risk hurting yourself!
Flexible "rubber" air hose would be safer than domestic cold water copper pipe.

You mean this stuff mmmm having looked around this forum for a while e.g. here loads of people are using domestic water copper pipe and fittings???

 

[Sidewinder]

You mean this stuff mmmm having looked around this forum for a while e.g. here loads of people are using domestic water copper pipe and fittings???

The ipe you have linked to in your first post is suitable for compressed air, it is designed for such.
There is also a difference in conveying gasses & liquids.
You can do what you like, I don't care, it won't affect me, but, I would never say it was acceptable to use domestic copper water pipe for compressed air use, no matter what fittings you use.
I bet I can also find something "official" that says you can't whether that be in the "BS" or in the manufacturers instructions.

It is not something that I would consider after 30 years in engineering, from craft to design, and I've seen a lot.

 

[JonnyAlpha]

The ipe you have linked to in your first post is suitable for compressed air, it is designed for such.
There is also a difference in conveying gasses & liquids.
You can do what you like, I don't care, it won't affect me, but, I would never say it was acceptable to use domestic copper water pipe for compressed air use, no matter what fittings you use.
I bet I can also find something "official" that says you can't whether that be in the "BS" or in the manufacturers instructions.

It is not something that I would consider after 30 years in engineering, from craft to design, and I've seen a lot.

That'll get some discussions going on here :-)

 

[brightspark]

nothing to discuss its well within its safety limits. ive used it for 40 years on the same compressor between the pump and tank with softsoldered fittings and it gets bloody hot http://www.copper.org/applications/plumbing/cth/technical-data/tables/cth_table3a.html

 

[JonnyAlpha]

nothing to discuss its well within its safety limits. ive used it for 40 years on the same compressor between the pump and tank with softsoldered fittings and it gets bloody hot http://www.copper.org/applications/plumbing/cth/technical-data/tables/cth_table3a.html

That works for me :-)

 

[Sidewinder]

nothing to discuss its well within its safety limits. ive used it for 40 years on the same compressor between the pump and tank with softsoldered fittings and it gets bloody hot http://www.copper.org/applications/plumbing/cth/technical-data/tables/cth_table3a.html

That table is for liquid not gaseous fluids.
As I said, you can do as you like, I would not.
There is NO way would I consider putting a gaseous load at up to 10 bar through a copper pipe designed to take a liquid load and specifically water!
It's your choice, it would not be mine, and as I say, IF I had time, I can bet that I could put a case together that proved that it was unsuitable.
Temperature is not all that needs to be considered.

 

[brightspark]

That table is for liquid not gaseous fluids.
As I said, you can do as you like, I would not.
There is NO way would I consider putting a gaseous load at up to 10 bar through a copper pipe designed to take a liquid load and specifically water!
It's your choice, it would not be mine, and as I say, IF I had time, I can bet that I could put a case together that proved that it was unsuitable.
Temperature is not all that needs to be considered.

not that it has much bearing but a standard pressed steel 1 gallon oil can can take 50 psi before the joints burst ive done it so im hardly wurried about the copper pipe . as u say its everyone to there own

 

[Sidewinder]

As you say each to his own, but just don't do it if you are in business, because IF something goes wrong, your business insurer would hang you out to dry.
DIY, then you would only have your home insurer to convince, or yourself to blame.
I just don't see the need to use unsuitable materials when the suitable ones are just as cheap if not cheaper!

 

[brightspark]

http://www.healthyheating.com/CIPH-Moncton/CIPH-Moncton-2011/Handbooks/copper_tube_handbook.pdfmakes some good reading

 

[Sidewinder]

Park that thought, I have made an enquiry, I'll let you know what comes back.
That document does not convince me.
Can you find a reference to compressed air distribution in it?
I failed in, what I admit was a very quick skim read.

 

[brightspark]

Park that thought, I have made an enquiry, I'll let you know what comes back.
That document does not convince me.
Can you find a reference to compressed air distribution in it?
I failed in, what I admit was a very quick skim read.[/quote selecting the right tube for the job ]table 3 compressed air

 

[Sidewinder]

Sorry, missed that completely!
Still not convinced, yet, as I said not what I would do it is an expensive option TBH.
Remember though even though the CDA say it's OK, if the manufacturer says no, then no it is really.
I have checked table 3 and no reference to 15mm copper tube there, so whilst I missed it, I still can't find a reference to say it is OK, I can't find one, yet that says it's not OK either.
However, I am guessing that you are talking about tube to EN 1057?
I'll check the standard and see what that says.

 

[the snooper]

here is another document from a copper pipe manufacturer showing max pressure of pipes page 26

 

[Sidewinder]

I have just checked EN1057, which is the standard for 15mm copper water pipes and it does not cover compressed air use.
Regardless of the pressure withstands, the En standard for copper 15mm water pipe does not deem it suitable for compressed air use.
As I have said, it's up to you.
There is nothing in the CDA document posted earlier referring to 15mm copper pipe either.

Please remember that there are as many different types of copper pipe as there are welding rods.

Looking at the second document linked for Yorkshire, then you could go for, perhaps EN 13348 tubes, I've not yet checked that standard, but, as it is a medical standard, if it is anything like the medical stuff I work with then it will be 10x the price of commercial materials.
Thus even if it were suitable, it would be stupidly expensive in comparison to other commercial materials.

You merely need to read the title of BS EN 1057, to realise that it is NOT considered for use as a compressed air pipe the title is:
BS EN 1057:2006+A1:2010 Copper and Copper Alloys - Seamless, Round Copper Tubes For Water and Gas In Sanitary and Heating Applications

 

[brightspark]

95 bar before the fittings leak no sign of 15mm pipe letting go

 

[JonnyAlpha]

Just knocked this up any thoughts on the plan?

I'll probably add an airline either between the Y connector and the copper and then a shorter airline to the gun to keep the regulator closer to the working end. In the guides in this forum the simple DIY solution only has one rise and ball drain valve so I may go for that but having a drop line will help wont it?

Back to the original question - (apart from the debate visa v domestic water copper and brass connections) any comment on my plan above, I may just go for the quick and simple DIY solution and omit the drop line and second ball valve?