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  1. #1
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    What's the highest oxygen and acetylene pressure used to braze copper pipes up to 3?

    The IFGC says you need a test pressure of 1 1/2 times the maximum working pressure. Need to get a value. I assume 30 lbs. for oxygen and 15 lbs. for acetylene. I figure to be safe at least 80 psig to test but would like to know what you "aces" think would be the maximum working pressure would ever be used? Thank you very much.
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  2. #2
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    I have not had an oxy rig on my truck since the truck with that rig was stolen, but for me, it always depended on the tip being used. You can put a lot more pressure into a large rosebud, for example.

    On my turbo torch, I turn up the pressure for my A32 "tailpipe" tip.

    The Harris or Victor sites should be a good resource for this info.
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  3. #3
    Join Date
    Mar 2008
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    Every acetylene gauges I’ve seen red lines at 15psi so I guess 15 and 30. I use a cutting tip and don’t hit the air when space allows.
    Honeywell you can buy better but you cant pay more

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  4. #4
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    Every acetylene gauges I’ve seen red lines at 15psi so I guess 15 and 30. I use a cutting tip and don’t hit the air when space allows.
    Honeywell you can buy better but you cant pay more

    I told my wife when i die to sell my fishing stuff for what its worth not what i told her i paid for it

  5. #5
    Join Date
    Aug 2002
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    Southold, NY
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    20 & 10 come to mind with the FDNY test but that was 40 years ago!

    Now I’m confused with the Test Pressure. The 3” copper is a Oxygen line?

  6. #6
    Join Date
    Sep 2005
    Location
    Atlanta GA area
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    Not 100% sure I understand the issue...

    For brazing copper lines... we use an Oxy/Acety torch... mini bottles... usually I run a #2 tip, with 2.5-3# Acy and 9-10# O2 pressure... sometimes I will adjust the Acy up to 4# and the )2 up to 11-12#... if I am brazing 1-1/8" pipe (rarely do).

    Brazing is as much an art form as a science... one needs to practice until the variable (gas pressure, pressure ratio, tip size, flame type and size, etc) are all in balance... AND, one understands the relevance of why each one would be changed to obtain a specific purpose!

    Oh, and then there are different tip sizes and types...

    Definitely more going on here... than an A or B thing...
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  7. #7
    Join Date
    Nov 2011
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    Strictly small oxy/acet. Torch sets:

    7 and 7. The only reason to crank up your regulators past 7 psi is for using the oxy cutting tip.

    You can braze 3” copper with a small oxy/acet. Rig, but you have to push the heat around...takes some practice. At that point, you’re prolly better off with a B tank.

  8. #8
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    Jan 2007
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    Mn the state where absolutey nothing is allowed
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    acetylene becomes unstable over a certain pressure, 15# or 30#, i forget, either way thats why max limits are set at 15psi. this way if you leave the acetylene hose full over the max pressure it wont act like nitrogycern(?) and explode if the hoses are smacked hard
    or so ive heard. thats the point of the disolved acetone in the tank, so it can be stable at higher pressures, but once out of the tank you have to keep the pressure low
    my boss thinks its possible to repeal the laws of physics

  9. #9
    Join Date
    May 2018
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    VA/DC
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    if youre asking on what to run your regulators at. It depends on the tip you are using. The size of the tip determines the pressure needed. its not a one and done setting.
    Guys have hit on the maximum pressures already.
    Check out the manufactures info of the tips you're using and see what they say the settings are.

  10. #10
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    Dec 2002
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    SouthEast NC ICW & Piedmont Foothills
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    acetylene above 15# psi will try to come out as a liquid, EXPLOSIVE.
    my normal set up: oxy 10-15# unless cutting tip in use, acty: no more than 7#.

    If you are ever really bored, inflate a balloon with acetylene and ignite, the further you are from it the better at ignition. Ear plugs are mandatory.
    It`s better to be silent and thought the fool; than speak and remove all doubt.

  11. #11
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    Mar 2015
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    Medford, N.Y.
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    Would a double tip be better on that size pipe? Is a nitrogen purge needed to keep the inside of the pipe clean for oxy use?

  12. #12
    Join Date
    Mar 2008
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    kansas
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    Quote Originally Posted by TechmanTerry View Post
    Would a double tip be better on that size pipe? Is a nitrogen purge needed to keep the inside of the pipe clean for oxy use?
    I could be wrong but I don’t think the op is doing med gas
    Honeywell you can buy better but you cant pay more

    I told my wife when i die to sell my fishing stuff for what its worth not what i told her i paid for it

  13. #13
    Join Date
    Nov 2014
    Location
    Northern Idaho
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    If you find the catalog online for the brand of torch set up you have, they’ll typically list recommended pressure settings.


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