tube packing for coils

Posts in this forum should be a complete method, educational, with pics where applicable,posts made in this area that don't fit this criteria will be moved at mods discretion.

tube packing for coils

Postby stubbydrainer » Sat Feb 25, 2012 11:27 pm

after witnessing a variety of ways to stop tube collapsing down while rolling a coil, with mixed results, I thought I would share a tip with you scruffy lot :lol: :lol:
I anneal enough tube to make the coil then pack it tightly with sand blasting abrasive grit, so long as it is kept dry it flows back out easily with a rolling back and forth motion , takes about 5 min. to get it out,and its ready for re-use, I reckon it will last forever,
Packing it in the is best done with vibration, a cordless drill with a bent bolt in it does the trick, I have the advantage of living on a high steep block , so after I crimp over one end I lay the tube over the batter and fill it with a funnel taped onto it to seal it and pour in the grit, touch the tube with the back of the vibrating drill to pack it and repeat this until the tube is full and crimp it over to seal up the end , then roll it up , easy, cut the end off and pour the grit out , flush out with yhe hose and your done
stubbydrainer
 
Posts: 728
Joined: Sun Aug 28, 2011 9:42 pm
Location: Northern Rivers, NSW
equipment: 4" perf. plate bubbler,2 1/2" pot with a triple wall liebig,
Small 8L pot for experiments & Gin, 6Kw 80ltr electric boiler , P.I.D/PWM controller
1/2 share with SBB in a 3" boka,

Re: tube packing for coils

Postby MacStill » Sat Feb 25, 2012 11:41 pm

The best tip I can give about rolling a coil is wind it off the coil, dont straighten it, dont fill it with anything..... just wind it over your mandrel.

Honestly I dont understand why people have so much trouble doing it :laughing-rolling:

Here's a coil for a 2" bok I made a while back on a bodgy home made jig, used a 16mm curtain rod for the inner and a 32mm section of the mrs vacume cleaner for the outer..... took 10 minutes :teasing-neener:

P3211384.jpg
You do not have the required permissions to view the files attached to this post.
MacStill
Lifetime Member
 
Posts: 16835
Joined: Fri Mar 18, 2011 1:40 pm
Location: Wide Bay QLD
equipment: Anything I choose :P

Re: tube packing for coils

Postby MozzMann » Mon Aug 27, 2012 9:24 pm

If you have trouble with the tubing the here is what you can do ,

Loosely wrap the required amount for your coil and then some, in a rough 12 to 14 inch coil and hold over a gas burner for a few minutes until there is a nice green tinge in the flame and then drop it straight into a very cold bucket of water, this quenches the copper tube and makes it very pliable, once you have your coil wound heat it again but let it air cool and the coils will be harder and more resilient. polish with Stainless Pot scrubber's to remove any flaking on the outside. or better still have it glass bead blasted to clean and burnish the exterior surface.

Mozz
MozzMann
 
Posts: 13
Joined: Mon Aug 27, 2012 5:55 pm
equipment: Small reflux and am building a larger unit with 8 columns 200 Lit Pot Capacity

Re: tube packing for coils

Postby dc13931 » Thu Nov 01, 2012 6:49 pm

fill her up with water and put it in the freezer. easy as pie. :handgestures-thumbupleft:
dc13931
 
Posts: 26
Joined: Thu Sep 27, 2012 12:58 pm
equipment: 3 inch column, vm head

Re: tube packing for coils

Postby MozzMann » Sat Nov 03, 2012 12:21 pm

I have wound a coil for a Chiller with 3/4 but it was quenched twice cleaned with Phosphoric and Vinegar then filled with course river sand ie Coffee Crystal size, and bent round an 11 " former but I don't know how tight you could go, years ago I saw a chiller made for a Dairy that was 1" tube that was filled with sand and then flattened so it was an oval flat sides and round ends and it was about 8 " dia curve.

I you quench it a couple of times it softens it dramatically which makes forming easy but also means you really pack to prevent collapse and kinking.


Mozz
MozzMann
 
Posts: 13
Joined: Mon Aug 27, 2012 5:55 pm
equipment: Small reflux and am building a larger unit with 8 columns 200 Lit Pot Capacity

Re: tube packing for coils

Postby VARocketry » Mon Oct 13, 2014 7:40 am

gents -- help please:

I've failed twice trying to bend a coil using 3/8" OD tubing using tube coil benders and frozen water, so I thought I'd try the salt/sand fill suggestion one more time ...

Ok, fill with salt/sand .... but how.?

Seriously, if you have a 20 ft length of coil, how do you get it solidly packed with salt/sand/whatever.? I don't recall this being discussed anywhere.

I got a bag of pulverized lime from TractorSupply, dipped out 3-4 cups of the fine lime and it sifted right through a sieve. I've taped a funnel to one end of the 3/8 OD tubing , filled it with the sifted lime, and taped the tubing to the side of kitchen cabinets, to hold the tubing vertical, so its about 9 feet up.

At the other end of the tubing, I duct taped a vacuum cleaner nozzle attachment to the tubing. Then apply suction using the handle's bypass hole to modulate the SUCK and observe when any lime has been pulled through. Only took a couple seconds for the lime to appear and I stopped.

But I don't assume its packed tightly in there .... yet? Will rapping the tube along its length to vibrate more down and compact the lime really work? Does this sound reasonable or is there a better suggestion?

Please advise me.
VARocketry
 
Posts: 24
Joined: Sat May 04, 2013 4:11 am
equipment: newbie, 2" POT Still, liebig condenser

Re: tube packing for coils

Postby P3T3rPan » Mon Oct 13, 2014 10:31 am

Okay, here is an old tradesman's (me) way of doing this.
This may elaborate on Stubbydrainers earlier good post
I was taught this as an apprentice plumber a life time ago.
If you have not done what Mac said, (the easiest way), and gone and straightened it out, you can fill it with fine DRY sand, tap it lightly with a piece of wood to settle it down and re-anneal it.
Crimp over or weld one end, (the bottom),so your sand stays in.
Leave enough room at the top to flush fit a cork or wooden plug.(I was taught to use molten lead for this)
Lightly crimp the plug in
Now, as long as your sand was dry or it will explode with superheated steam, you can re-anneal the tube as many times as you like without removing the sand. Annealed copper tube bends as easily as copper wire but becomes hard again with each bend or part thereof (work hardening).
Removing the sand is easy, cut off one end and shake.
I have used this technique many times on a range of copper tube sizes up to 50mm
For safety I will say again the sand must be completely dry. In my workshop we have a container of dry sand that gets reused over and again.
When re-annealing it is the colour of the copper that indicates success, not the colour of the flame as suggested in an earlier post. We are looking to make the copper cherry red in the area we want to bend.
Dropping it in water (quenching) does not make the copper soft it merely makes it cold enough to handle without affecting the softness of the copper but be careful to keep you sand dry.
Air cooling will not make any difference to the resilience of the copper (wtf). The only thing that makes copper hard is to work it ,ie, bend or tap or squash it
P3T3rPan
 
Posts: 435
Images: 0
Joined: Tue Jun 25, 2013 7:34 am
Location: Wellington NZ
equipment: Self made 100mm copper,6 perforated plates plus packed section on 50L ss keg
60L fermenters. Offset Carter Head
3v beer rig

Re: tube packing for coils

Postby VARocketry » Mon Oct 13, 2014 1:57 pm

P3T3rPan :

Thanks, mate. I re-read stubby's post, too. I think the annealing makes a lot of sense in bending the tubing. And you can't do that with the water-filled or frozen water technique.
I'll give it a go and report back.
VARocketry
 
Posts: 24
Joined: Sat May 04, 2013 4:11 am
equipment: newbie, 2" POT Still, liebig condenser

Re: tube packing for coils

Postby BikinArak » Mon May 18, 2015 2:45 pm

I had ago making a pipe roller on the mandrel, then I tried filling it with water and freezing it which helped a lot. But I am wondering if I am having trouble because this pipe is for aircons and has a very thing wall, maybe 0.3mm
BikinArak
 
Posts: 12
Joined: Sun Apr 26, 2015 6:23 pm
Location: Where Arak comes from up north.
equipment: Building CM reflux.


Return to Tips From The Workbench



Who is online

Users browsing this forum: No registered users and 10 guests

x