Flaring and you! (An illistrated guide by the pony!)

In any industry one of the most useful and robust ways of joining two pipes has been the Flare, it is serviceable and reliable, but doing it right has all ways been sort of an art requiring a thorough and well-developed technique!

This Guide is to help you form a rudimentary technique that you can build upon to form your own effective method of flaring.


What IS a Flare?

A Flare is when you widen the end of the pipe to form a 45-degree cup, this fits over a mirrored fitting (It is basically an inverted 45degree cup) made of brass that a Nut is then tightened over it, sealing the two pieces together. The better the fit, the better the seal (Well duh :) ).

So what does one need to make a good flare? Well obviously you need a flaring tool! In refrigeration all flares are commonly of the 45-degree SAE type.

Needed Tools:
- Oil (I personally use POE oil, as it both cleans and lubricates at the same time)
- De-Burring tool (I use a centre punch and a metal file to help achieve a perfectly clean pipe head)
- Flaring Tool (Take a guess at that one!)
- An assortment of SAE Wrenches for the sizes of Nuts you'll be using

Refer to the photo.

Steps to a perfect flare

1- Cut your pipe to the desired length and make any needed bends.
2- slide on the flare Nut and push it back out of the way.
3- Use the metal file to file down the pipe head till it is clean and level.
4- Use the centre punch or other de-burring tool to make sure you have a clean flat inside diameter, and make sure the out side diameter is also free of nicks or irregularities.

5- Set the pipe into the locking part of the flaring tool leaving about 5mm or so above (I don't have a ruler to measure exactly). By this point it should be smooth on all parts of the head, and parallel to the tool block.

6- Apply a small even amount of oil on the pipe head and the flaring tools head, Lock the flaring unit to the locking base and centre the tool and tighten it (BUT don't start the flaring process) Make sure you are properly aligned with the pipe! Tighten more, check again to make sure you are centred!

7- Once you are sure you are completely aligned down the pipe and tools axis start the flaring by slowly tightening the tool to form the flare, once you can't turn any further torque it once then loosen off.

8- remove the locking unit from the pipe and check to see if it fits inside the Nut snugly, there should be less then a 1mm gap between the new flare and the bolt walls, if there is not, repeat steps 6 to 8 till it fits perfectly.

9- Now that you have the female part of your flare made set it aside and grab the oil! Care fully oil the male flare on the head and threads (Do this with the nut on the pipe as well) Now you can start bolting them together, first do it by hand and make sure every thing is well aligned and tightened, after hand tightening it and every thing is nicely aligned torque it hard as you can with two small crescent wrenches.

10- You're ready to test it now! Give it a good wiggle, the bolt flare assembly should move as one solid unit with no slip going on at the nut to pipe interface

don't use a file:)

you don't want any vile residu in the pipes would you ;)

Make sure you get the right form of the tool as well. Mine doesnt seem to be rated for refrigeration tubing and my tube just gets pushed thru the grip.

Quote:

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Originally Posted by n00b 0f l337

Make sure you get the right form of the tool as well. Mine doesnt seem to be rated for refrigeration tubing and my tube just gets pushed thru the grip.

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You mean copper pipe? That is what flaring tools are designed for...

Are you sure your using the right size on the clamp part of the flaring tool? Do you have it tightened down as hard as you can?

I dont know what else they would make a flaring tool for other than for copper tubing.

Plumbing. Its 2 different sizes of tubing.

I had an crappy flaring tool that just dudnt hold on metric or refrigerant tubing. It was cheap and in the end it joust caused more troubles than it did good.

Car brake lines and fuel tubing use flaring tools, there not copper at all :)

Well you can use a file if you know how not to get the debrie in there or know how to get it out, since the pipe is open at both ends a quick burst of any gass of your choice will clean it nicely. Secondly yes there are two diferant types and you definatly want to make shure you have the correct one for the material you'll be working with.

As they say, you get what you pay for, Never buy cheap tools, it is never worth what litle you'll save!

Bumping as there been mention of flares and this is a good guide example IMO

hmm, I've never used oil to flare, persnally I haven't run into problems, but would you mind elaborating as to why you use oil before flaring?

I find it helps them turn out smoother and more even, then with out the oil.

1 vote for sticky, great guide :toast:

Flares are evil but I am willing to entertain the idea. Xeon, post some more pictures, (An illistrated guide by the pony!) is not very illustrated right now. take good pictures of every step, then it would make a good sticky.

Ya, I am having truble with my crappy camera and flash with shiny copper, tried a fiew differant methods but non seem to be geting fare!

maybe a bit of a dumbass question, but will ask anyway:

when purging, the system is on some pressure right? do flare fittings make sure bothe ends wont be seperated bacause of the tight flare? otherwise I should study more on how to pruge...

Wth?

when purging, the system is on some pressure right?
Yes

do flare fittings make sure both ends wont be separated because of the tight flare?

? This makes no sense as you all ready answered your own question or did you mean some thing ells?

If your asking about purging would it not be more sensible to ask in a thread geared for purging? Flares are alternative in brazing, they are generally used on larger commercial systems.

[QUOTE=Xeon th MG Pony]Wth?

when purging, the system is on some pressure right?
Yes


When purging the system is left open to allow the gas to escape, you just want enough flow to displace the oxygen. while you can't say there is no pressure ,a yes without explanion is misleading. It should be very low,only measurable in ounces per square inch. Or the pressure will blow pinholes in your braze joint or not allow in to flow into the joint. You do not block off the loop and put 20 psi into it.Too fast of a flow also cools the tube and that will make it harder to get to temperature.

^ What he said. but being it is totaly irrelivant to flaring and doing the flares I did not see any use in any thing more then a single word answer.

In fact could you please deleat the off topic posts and or split them out of this thread?

thanx for explaining...

sorry for poluting your thread pony ;)

but I was thinking that flares were nescesary for purging, but I was wrong. But that was the reason I asked here...

can be deleted is wanted...

Its alright, we are all here to learn. Well maybe not all lol.

hey xeon, I always had preblems with flares, a little vibration here, some system shaking there, and they start leaking on me. Do they just not do well under harmonic stresses or are mine not tight enough, almost twisting the pipe so I cant imagine it getting any tighter. I know Jin hates flares for this reason, so I am thinking the flare as good and flexible solution as it is is not the best for durability.

they are just fine for durability, it is critical to properly oil both sides before tightening them, and you need to use some force and torque them well, and use good pipe designs that limit vibrations and such I've had flares hold a vacuum in one unit that I hauled around for moths, I never imagined there'd still be a vacuum but once the seal was cracked :D

So it comes down to the basics:
- Did you make sure both surfaces are clean and in good condition?
- Did you make the flare properly? (Should fit snugly to the inside of the nut)
- Did you oil the flare on both sides? (Critical for a good tight seal)
- Did you torque it?

I have about a 70apx pound grip and I grip the two wrenches as hard as I can to torque them being care full not to strip the nut (Back when I was doing LOTs of flaring and bolt tightening lol)

Quote:

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Originally Posted by Xeon th MG Pony

they are just fine for durability, it is critical to properly oil both sides before tightening them, and you need to use some force and torque them well, and use good pipe designs that limit vibrations and such I've had flares hold a vacuum in one unit that I hauled around for moths, I never imagined there'd still be a vacuum but once the seal was cracked :D

So it comes down to the basics:
- Did you make sure both surfaces are clean and in good condition?
- Did you make the flare properly? (Should fit snugly to the inside of the nut)
- Did you oil the flare on both sides? (Critical for a good tight seal)
- Did you torque it?

I have about a 70apx pound grip and I grip the two wrenches as hard as I can to torque them being care full not to strip the nut (Back when I was doing LOTs of flaring and bolt tightening lol)

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Another tip, if you don't feel safe, use flare gasket (copper)... thats what I do on all my flare job (just for filter and drier for more experimental units I know I will have to replace filter and drier down the line). Bit hard to put it at right position on some odd ones, but it works fine and seems to work fine.

I only use double flares .

I can't seem to understand what the nut is...

Do double flares also have a "male flared" side?

Quote:

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Originally Posted by jinu117

Another tip, if you don't feel safe, use flare gasket (copper)... thats what I do on all my flare job (just for filter and drier for more experimental units I know I will have to replace filter and drier down the line). Bit hard to put it at right position on some odd ones, but it works fine and seems to work fine.

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Where do you get the copper flare gaskets?