15mm copper cooling coil

[cheb]

This is the current connection between the compressor and the workshop piping. I'd like to have a longer piece of copper connecting the two and a coil would do the job nicely, similar to the 22mm ones in water tanks.

I don't want to make it myself for various reasons, are they available off the shelf or can you point me towards someone who can make me one for money?

 

[hotponyshoes]

You can get rolls of copper pipe off the shelf so, unless regular size coils are essential, just get one of those and pull it out?

 

[cheb]

Does that bend neatly without having to faff about with sand/ice/salt/water/unicorn tears? I'd like the coil to be about 150mm in diameter.

 

[Sparky666]

If it’s 22mm Any local plumber with a hand bending tool will knock up in a few minutes, can see what looks like flat spots on the tube frame a former/roller, as pony mentioned purchase a coil and just form it yourself.
150mm a little tight though. Could look at sweeping bends and solder them? Just seen 15mm

 

[gaz1]

simple way for you with instructions

 

[gaz1]

personally your wasting your time you would be better off using 4 lengths of upward pipe and 4 tees

then fit them inside a chimney so the chimney will cool it down as the pipe warms up and hot air rises from the cool floor

 

[brightspark]

i dont bother with any of that lot and just use a secondary tank near the end of the line with a water seperator on the outlet . it gets used full whack sandblasting with verry little water getting in to the separator even after 25 minutes

 

[hotponyshoes]

personally your wasting your time you would be better off using 4 lengths of upward pipe and 4 tees

then fit them inside a chimney so the chimney will cool it down as the pipe warms up and hot air rises from the cool floor

i dont bother with any of that lot and just use a secondary tank near the end of the line with a water seperator on the outlet . it gets used full whack sandblasting with verry little water getting in to the separator even after 25 minutes

Ah, I presumed he wanted it to absorb vibration rather than as a cooler?

 

[Maker]

Ah, I presumed he wanted it to absorb vibration rather than as a cooler?

Why not just use a bit of flexi hose then? I cut the first twelve inches off my air hose to go between the compressor and the hard tubing.

 

[123hotchef]

Ah, I presumed he wanted it to absorb vibration rather than as a cooler?

Id be using a rubber hose then

 

[cheb]

A bit of both really, the primary thing is the vibration and the longer it is the better the cooling.

 

[gaz1]

Id be using a rubber hose then

same here flexi hoses are more known for being too weak even the stainless steel wraped ones the rubber is more suited to his system and will last longer

A bit of both really, the primary thing is the vibration and the longer it is the better the cooling.

you wouldnt cool that much to be honest and personaly id run a coil through a dust bin full of cold water far faster if you really want to cool it and drain it through a teed off pipe

 

[Screwdriver]

This is the current connection between the compressor and the workshop piping. I'd like to have a longer piece of copper connecting the two and a coil would do the job nicely, similar to the 22mm ones in water tanks.

I don't want to make it myself for various reasons, are they available off the shelf or can you point me towards someone who can make me one for money?

View attachment 353122

Most of the benefit of having a long drop for cooling is already in place, you're chasing a tiny additional benefit. I wouldn't recommend having a trap such as you've shown - where is any condensed water going to flow? Same thing with a coil, the water has to drain somewhere and it's always going downhill...

On my setup I have one long black iron pipe connected to the compressor tank via a rubber hose and it goes up to the ceiling before it gets into the system. T'd off the bottom with a six inch drop to a drain valve. If if need any drier air, I fit a water separator. So frankly I'd lose the U bend trap, fit a rubber hose sloped down from the output and go long on the vertical drop.

It occurs to me there could be some benefit in having a slightly larger diameter drop tube which in theory ought to encourage condensation as air flowing out from the smaller diameter tube expands. No idea if that is true for a pressurised system?? What would happen when pressurised air flows into a larger diameter tube at the same pressure?? When the air is flowing, is the pressure higher in the smaller diameter tube??

 

[brightspark]

Most of the benefit of having a long drop for cooling is already in place, you're chasing a tiny additional benefit. I wouldn't recommend having a trap such as you've shown - where is any condensed water going to flow? Same thing with a coil, the water has to drain somewhere and it's always going downhill...

On my setup I have one long black iron pipe connected to the compressor tank via a rubber hose and it goes up to the ceiling before it gets into the system. T'd off the bottom with a six inch drop to a drain valve. If if need any drier air, I fit a water separator. So frankly I'd lose the U bend trap, fit a rubber hose sloped down from the output and go long on the vertical drop.

It occurs to me there could be some benefit in having a slightly larger diameter drop tube which in theory ought to encourage condensation as air flowing out from the smaller diameter tube expands. No idea if that is true for a pressurised system?? What would happen when pressurised air flows into a larger diameter tube at the same pressure?? When the air is flowing, is the pressure higher in the smaller diameter tube??

the pressure is the same in both but the velocity is higher in the thinner bore pipe but less cfm flow

 

[Screwdriver]

the pressure is the same in both but the velocity is higher in the thinner bore pipe but less cfm flow

Sounds about right regards velocity but I don't understand how cfm can change, surely that needs to stay constant no matter what the pipe diameter?

If the smaller pipe is flowing air twice as fast at let's say half the volume, surely the bigger pipe has twice the volume travelling at half the velocity??

 

[Olderisbetter]

Now i have a use for this

 

[Screwdriver]

Make a cracking induction heater...

 

[Maker]

It occurs to me there could be some benefit in having a slightly larger diameter drop tube which in theory ought to encourage condensation as air flowing out from the smaller diameter tube expands. No idea if that is true for a pressurised system?? What would happen when pressurised air flows into a larger diameter tube at the same pressure?? When the air is flowing, is the pressure higher in the smaller diameter tube??

The pressure is always higher upstream*, there'll always be pressure loss through a pipe, fitting, restriction or expansion, and that's a bad thing, any loss in the pipe is a less power to your air tool. It's just a small frictional loss though, it's not like twice the diameter gives you half the pressure, it'll have basically the same pressure at half the velocity.

*Aside from obvious exceptions, like a pump, or a long vertical pipe.

Sounds about right regards velocity but I don't understand how cfm can change, surely that needs to stay constant no matter what the pipe diameter?

CFM won't change, in terms of air in must equal air out, but a smaller pipe will be a greater restriction, so you'll get less air into the pipe in the first place, when compared to not having the small pipe to transition to the big one.

 

[julianf]

Now i have a use for this
View attachment 353165

The walls on those are (in my findings) thinner than normal copper pipe.

I know that I have to have a reducing valve on my thermal store as the coil is only rated for 3bar.

I suspect throwing 10 bar at a hot water tank coil would not work well.

 

[CompoSimmonite]

Why not use a whole hot water tank ? You could pipe the air through the coil and fill the tank with water - after sealing lower outlets