compressor hard line

[pondy]

im going to run a hard air line my garage, going to use 15mm copper but have a few questions before i start buying parts

are soldered joints preferred over compression joints, read compression have a working pressure of 7 bar, not what soldered joints have. there will be a few places i will have to use compression joints, a straight compression joints joining the pipe to water trap etc.

i plan on fitting a couple of water traps, one with a regulator as i sometimes use a schutz gun and need to turn the pressure down. a quick look on ebay came up with these

http://www.ebay.co.uk/itm/162439253782

http://www.ebay.co.uk/itm/252751745509

i need a flexible pipe to connect the compressor to the pipe work. would something like this be ok?

http://www.toolstation.com/shop/p24989?gclid=CjwKEAjwlKLHBRDztKr6wMnRthMSJAAL

i want an auto reel hose, lots on ebay, any one eitb experience of the on bellow, want one with a decent 3/8 id hose

http://www.ebay.co.uk/itm/272544590847

thanks

 

[rtbcomp]

I've used both compression & solder without problems at 100 psi.

You should be OK with the PCL regulator, it's a known good brand. I use a Parker reg which has been fine, shop around for those though, prices can vary a lot.

 

[Mee]

I prefer soldered as some cheapie compression joints have hit the market recently.

 

[smpw]

Just about to do the same here although i am pondering if i should go for 22mm or 15 mm, as this has been discussed in a few previous threads.This company http://www.pipefittingsdirect.co.uk/contents/en-uk/d29.html
does a flexi joint half way down the page although I am not sure what the bore size is and delivery is expensive. I will only likely be using for air tools although I will be disappointed if i fit 15 mm only to find a need more air volume
and regret not fitting the 22mm.

 

[DrDeAtH]

Go for the 22mm. Better to build in extra capacity at the start, rather than having to upgrade later.

 

[brightspark]

22 mm definitely . more volume more cooling

 

[123hotchef]

what he said 22mm more surface area of copper results in cooler air at the tool

 

[smpw]

Ok Chaps looks like it 22mm then. I know Pondy mentioned a braided flexible hose connector from the tank to the pipework. This would be an easy solution as these are readily available, however would the bore be sufficient for 22mm copper pipework as appreciate Pondy was
talking 15 mm pipework. I also have the Wolf Dakota with the 3/4 Plug.

 

[123hotchef]

what is the bore of the flexi?

 

[123hotchef]

as said before i used a washing machine fill hose for my 2 compressors

 

[DrDeAtH]

If you're coming out the end of the receiver to your hard pipework, then 3/4 inch bore hose would be the best way.

 

[smpw]

I believe they are 10 mm bore - hadn't though about washing machine fill hoses

 

[123hotchef]

u have now!

 

[Parm]

I prefer soldered as some cheapie compression joints have hit the market recently.

Would you care to share which make/brand they are. Might be quite usefull to some of the less experienced members, myself included

 

[rtbcomp]

1m of 22mm has a surface area of 1000 * 22 * pi = 69115 Sq.mm, volume = 1000 * (11^2) * pi = 380132 Cu.mm, vol/area ratio = 380132/69115 = 5.5:1

for 15mm pipe SA = 47123 Sq.mm, Vol = 176714 Cu.mm, vol/area ratio = 176714/47123 = 3.75:1

Which means (I reckon) for 22mm pipe you have more volume/area than for 15mm, (ie less area/volume); as cooling depends on the the surface area, you get less cooling per litre of air with the larger diameter pipe, so assuming the 15mm pipe is adequate in terms of airflow, it would better at cooling than the 22mm. Look at it another way, with the smaller tube a greater proportion of the air is closer to the pipe wall than with the wider pipe. Or another way; radiators, intercoolers, boilers &c have multiple smaller tubes than a few larger ones. Or another way, with the larger pipe the air is moving more slowly so it has more time to cool down.

I use over 30 feet of 15mm from my 14cfm compressor to my blast cabinet without any problems, so you may well be better off with 15mm in terms of cost and cooling efficiency.

 

[123hotchef]

dam that is a good way to put it !!!!

 

[Burdekin]

Some old threads with more info.

http://www.mig-welding.co.uk/forum/...tions-copper-pipe-plumbing.62026/#post-781035

http://www.mig-welding.co.uk/forum/threads/new-compressed-hard-airline-design.60065/

http://www.mig-welding.co.uk/forum/threads/deleting-compressor-regulator.61804/#post-780585

 

[Mee]

Would you care to share which make/brand they are. Might be quite usefull to some of the less experienced members, myself included

No idea, mate warned me some had hit the market and he had some and he is a plumber who had to return to several jobs because of them.

 

[pondy]

I've had a look at some flexi connectors and the hose bore is tiny, around 5mm, ive opted for a couple of tail ends and some 3/8 air hose with some jubilee clamps. I'm going for 15mm hose, i run a few die grinders, plasma cutter and occasional impact gun for car work, use a small 50l compressor which has been fine for years so don't see an upgrade on the cards

 

[pondy]

finally got this done