Reusing a brass flare fitting?

firstbase · Jun 3, 2018

Is there any loss of integrity if I reuse a flared brass fitting? Assuming no scaring/scratches on the flared end. Threads are ok if retightened?

gaston · Jun 3, 2018

I hate brass its very brittle at the best of times .
If its on a fuel line and you have doubts replace it or it will haunt you

RT Firefly · Jun 3, 2018

Greetings,
Mr. fb. While Mr. g does have a point, I would not hesitate to re-use a brass flare nut fitting. One has to be careful not to over tighten. I would suggest investing in a cheap set of flare nut wrenches.

https://www.harborfreight.com/5-pc-sae-double-end-flare-nut-wrench-set-68865.html

The bonus is you get to buy more tools!

I would NOT re-use any compression fittings.

DavidM · Jun 3, 2018

Done it dozens of times. No problems.

David

psneeld · Jun 3, 2018

Me too, the trick is not overtightening and making it work hardened.....

https://en.m.wikipedia.org/wiki/Brass

*By varying the proportions of copper and zinc, the properties of the brass can be changed, allowing hard and soft brasses

gaston · Jun 3, 2018

Stolen C&P

Brass is susceptible to stress corrosion cracking,[26] especially from ammonia or substances containing or releasing ammonia. The problem is sometimes known as season cracking after it was first discovered in brass cartridges used for rifle
Stolen C&P

ammunition during the 1920s in the British Indian Army. The problem was caused by high residual stresses from cold forming of the cases during manufacture, together with chemical attack from traces of ammonia in the atmosphere. The cartridges were stored in stables and the ammonia concentration rose during the hot summer months, thus initiating brittle cracks. The problem was resolved by annealing the cases, and storing the cartridges elsewhere.

psneeld · Jun 3, 2018

Funny, my brass fitting are made for fuel or oil lines....not ammunition...maybe the correct alloy for their use

gaston · Jun 3, 2018

psneeld said:
Funny, my brass fitting are made for fuel or oil lines....not ammunition...maybe the correct alloy for their use

How do you know ? and : Are they Chinese ? Australian ? South African ?

sdowney717 · Jun 3, 2018

I reuse everything and also compression fittings. You put some Rectorseal T plus 2 on them. Needs to go on a dry, not a wet fitting.

FF · Jun 3, 2018

The flair nuts come in 2 common forms.

Some are long that help the fitting by supporting the tubing , others for refrigeration are perhaps 2x as thick, but are short.

If the tubing flair seat is in OK shape , not cracked , either flair nut can be reused many times.

psneeld · Jun 3, 2018

Someone must think its normal...... to me the main prupose of using these fittings in fuel and hydraulic systems is ease in taking lines on and off rather than cutting hose off barb fittings.

https://www.grainger.com/product/38...6677!&ef_id=VFTJaQAAADjffh8e:20180603114257:s

sdowney717 · Jun 3, 2018

psneeld said:
Someone must think its normal...... to me the main prupose of using these fittings in fuel and hydraulic systems is ease in taking lines on and off rather than cutting hose off barb fittings.

https://www.grainger.com/product/38...6677!&ef_id=VFTJaQAAADjffh8e:20180603114257:s

For refrigeration work to help seal against gas loss. Overkill for fuel line.
In refrigeration work, you tighten so much as to deform - plastisize the copper to create a perfect seal. You really crank down on those, there is a spec to tighten them. Those tubing fitting nuts are also real thick and tough for refrigeration use.

I reuse a fitting but if it leaks, and tightening, etc... whatever, wont stop the leak, then it needs replacing.

psneeld · Jun 3, 2018

not what a friend expert marine engineer thinks...

its what he suggested for Simi 60's fuel fitting leak that no goop was fixing.

but obviously any suspect fitting or one giving you constant leaks should be replaced (eventually).

The answer to the question though is that flare fittings are really not one time use items.

diver dave · Jun 3, 2018

gaston said:
Stolen C&P

Brass is susceptible to stress corrosion cracking,[26] especially from ammonia or substances containing or releasing ammonia. The problem is sometimes known as season cracking after it was first discovered in brass cartridges used for rifle
Stolen C&P

ammunition during the 1920s in the British Indian Army. The problem was caused by high residual stresses from cold forming of the cases during manufacture, together with chemical attack from traces of ammonia in the atmosphere. The cartridges were stored in stables and the ammonia concentration rose during the hot summer months, thus initiating brittle cracks. The problem was resolved by annealing the cases, and storing the cartridges elsewhere.

My dad did a lot of handloading. He would anneal the used brass by putting them in an oven on a cookie sheet vertically and at some point in time tipping them over into an oil ( I think). But yes, clearly cartridge brass will cold work harden, become "brittle", and crack when restressed.
I don't know if I would take this directly into a "don't reuse flare fittings", due to a likely much lower stress. dunno for sure.

gaston · Jun 3, 2018

Its impossible to know just how many times a fitting has been handled and by whom

For a few dollars on a older boat why take the risk ?

In the time this post has been up I could have driven 40k to plumbing supply place returned fitted the fitting and be back in business :popcorn:

RT Firefly · Jun 3, 2018

Greetings,
IF you replace the fitting, you have to cut the pipe and re-flare. Do you have the appropriate equipment AND is the tubing long enough to do so? IF the fitting is in question, you'll possibly have to replace the tubing as well.

diver dave · Jun 3, 2018

https://www.finehomebuilding.com/2016/09/26/make-flare-connection

I suspect the cost, driving and stocking is not the issue with the lack of reuse; It's the cutting, trimming, and flaring of the copper tube.

gaston · Jun 3, 2018

diver dave said:
https://www.finehomebuilding.com/2016/09/26/make-flare-connection

I suspect the cost, driving and stocking is not the issue with the lack of reuse; It's the cutting, trimming, and flaring of the copper tube.

Its a pleasure boat all boats need to be repaired and updated for time to time so I do what ever need to be done right dont take corners.

20km out to sea and the fitting lets you down ? Ok $5 x 2 for the fittings copper pipe $10 flaring tool $15 1/3 the cot of a cheap bottle of red wine .

AusCan · Jun 3, 2018

I reuse them all the time, even though I keep a bunch of spare pipe, fittings, tubing cutters and benders on the boat for projects.

firstbase · Jun 3, 2018

Thanks guys. The are 1/2" nipple fittings being used on the never ending oil change system install documented excessively elsewhere including RTF's PM inbox. Just asking as I have to take a couple apart that were tightened up yesterday. Which I knew I would have to do. I meant to do it. Honest. I didn't make a mistake or anything. Nope.

DHeckrotte · Jun 3, 2018

I reuse/reassemble these things as necessary. To ease future disassembly issues and to make successful assembly happier, I thumb on a smidge of Teflon pipe dope (both to aid the seal and to lubricate the nut). Of course, you cannot slip the old compression ring off and reuse it elsewhere; it will have been reduced in diameter and pressed into the tubing.

FF · Jun 3, 2018

"flaring tool $15"

Not if you get a good one from the refrigeration guys.

No body wants a leak , but the refrigeration guys REALLY don't as they will have to come back and service the system .

firstbase · Jun 3, 2018

I've been using Rector 5 on everything even though hydraulic supply told me it wasn't necessary on flared. They said it wouldn't hurt so...why not? It's sitting right there so too easy.

diver dave · Jun 3, 2018

DHeckrotte said:
I reuse/reassemble these things as necessary. ... Of course, you cannot slip the old compression ring off and reuse it elsewhere; it will have been reduced in diameter and pressed into the tubing.

Oh Oh, Now you have done it. Compression fittings. :banghead:

sdowney717 · Jun 3, 2018

diver dave said:
Oh Oh, Now you have done it. Compression fittings.

My whole boats fresh water system uses them, and pretty much ok. Problems happen when the copper tubing gets corroded, you try to tighten too much and the fittings can distort, it will drip. I also have used rectorseal T plus 2 teflon thread sealant, and it is really pretty good stuff, although it needs to be used on dry fittings, if wet it doesn't like to stick to the metal. That stuff also works fantastic on rubber hoses, keeps them from sticking to metal, it really works well.

One nice thing, copper pipes kill bacteria and virus, it purifies your water.

Lepke · Jun 3, 2018

In comparison brass is hard and copper is soft. When tightening the flare nut, the flare in the copper is forced to conform to the brass flare fitting. Making a tight seal. I'm 70 and been reusing flare fittings for about 55 years without problems.

gaston · Jun 3, 2018

Compression fittings those 2 words dont belong on any boat

psneeld · Jun 3, 2018

Don't the injector lines on a Ford Lehman at the fuel pump end have some sort of compresion fitting?

gaston · Jun 3, 2018

psneeld said:
Don't the injector lines on a Ford Lehman at the fuel pump end have some sort of compresion fitting?

If they leak and pop off the answer is yes

Reusing a brass flare fitting?

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