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Same pipe, i schock cooled it under water. Looks pretty good. You can also clean it with one of the fleeces instead of using water but you need to wait until its cold. Thats why i prefer this method.
I just take the brazed piece with a plier and hold it under a water stream. Also you can tilt water on it...
I found a pretty good pic of while brazing, on my PC, you can see the liquid brazing metal here.
Edit: If there are any questions, feel free to ask in this thread. If you want to i could braze other parts also (evap, a complete phase change, drier...)
This is a very nice guide, deserves a sticky...
Yes that is true, but how long do you have it on ? Maybe 1 second ? Later the oxygene rich gas flow will oxidize the soot as you called itQuote:
Thats a big nono ... while you have a flame like on a gasligther, soot gets into the connection and the setup gets damaged.
Tell me something about it :D This is dangerous in a hands of a noob...Quote:
There is no risk of a explosion btw, concentration it too low.
I start my torch this way:
-tip pointing away from me ;)
-start mapp/acetylene
-fire it up with a 2nd torch or special tool
-turn oxygene on
this is a safer way of doing it.
when brazing a evap watch out not to push the tip of the torch too close to the evap, i had a accident when the evaporator filled up with oxy/mapp and exploded (the shockwave comming out of the sucktion line would burn my face if i havent had my welding mask on, gloves etc., yes i do such stuff in a welding mask, much safer)
When describing how to braze we should start with the dangers of using a torch. I think we should point out some stuff as well as give some tips.
Thanks :)
1 second is a long long time...Quote:
Yes that is true, but how long do you have it on ? Maybe 1 second ? Later the oxygene rich gas flow will oxidize the soot as you called it
I attached a pic as you see Oxigen and Acetylene get mixed up at the end of the connection. If the Acetylene burns into the connection (whats possible) soot will deposit here. The Oxigen has its own canal.
You are receiving a high risk with that...Quote:
I start my torch this way:
-tip pointing away from me
-start mapp/acetylene
-fire it up with a 2nd torch or special tool
-turn oxygene on
this is a safer way of doing it.
If the flame gets into the connection and throught it, it will burn in the hose... If youre not fast enought the flame will get into the Gas Tank. I dont want to mention what could happen now...
Well, when having no flame and the gases turned on. The time between gas flows out and the point of launching is most of the time >15sec.Quote:
Tell me something about it This is dangerous in a hands of a noob...
It takes much longer to fill a room with that much acetylene that the concentration is high enought to explode.
It can not. Theres no oxygene there! It can burn only after the tip's endQuote:
If the Acetylene burns into the connection (whats possible) soot will deposit here. The Oxigen has its own canal.
Like earlyer - no possibility, no oxygene= no flame, no explosionQuote:
You are receiving a high risk with that...
If the flame gets into the connection and throught it, it will burn in the hose... If youre not fast enought the flame will get into the Gas Tank. I dont want to mention what could happen now...
Thats not the problem. Your making a small "cloud" of oxygene with acetylene and your risking igniting that thing. I saw a really small "cloud" like that igniting - nothing nice to watch (unless on Reality TV)Quote:
Well, when having no flame and the gases turned on. The time between gas flows out and the point of launching is most of the time >15sec.
It takes much longer to fill a room with that much acetylene that the concentration is high enought to explode.
Well... Acetylene burns by it self, it doesnt need Oxigen. Propane and Butane cant burn without Oxigen
I know what you mean, but the concentration is not high enought in a normal room. The cloud will rise up under the roof and/or distributes in the room. The quanty wich comes out of the torch is not enought to make a cloud like this.Quote:
Thats not the problem. Your making a small "cloud" of oxygene with acetylene and your risking igniting that thing. I saw a really small "cloud" like that igniting - nothing nice to watch (unless on Reality TV)
Well Berkut is correct you always start acet first then oxy and when shutting off oxy first then acet . Every time you hear a pop you are sending a shock wave and flame back into the tip and down the hose (like when you shut off acet first) and that will damage your torch and regs there most likely is a flame aresstor before the reg so that helps but if that doesn't work bye bye regulator .
Also acetylene will not burn without oxygen and the soot you get is on the outside of the tip which can be cleaned so don't worry about the tip getting soot on it if you want to reduce the amout of soot turn the acet up, dont let it trickle out or you get the little solid pieces floating around .
Shock cooling a piece that has been brazed is a no no you can crack the connection you just made, let it cool on its own and you connection will be a lot stronger. And when brazing where ever the copper is red hot, the flux will go just be sure to heat the tube and the cup equally and if you see green flame pull the torch back imediately that is the sigh that you are burning the copper, which is not good at all...
when we say acetylene will not burn without oxygen we mean if there is no air/oxygen present if the space of pure acetylene it will not burn. Acetylene will burn from the tip alone but the tip is allowing it to mix with the air in the room...
Acetylene may decompose but not burn.
Everyone I know that uses A/O torches opens the acetylene first and ignite an when its all fired up then they open the oxygen wery carefully...If you turn it up too fast it will make a loud pop, and the flame will die. That is the way I have bee tought to ignite a torch and that is the way I have seen people who do these things for a living ignite the torch...
Thats wrong...Quote:
Originally posted by NitroRat
when we say acetylene will not burn without oxygen we mean if there is no air/oxygen present if the space of pure acetylene it will not burn. Acetylene will burn from the tip alone but the tip is allowing it to mix with the air in the room...
See:
http://gasekatalog.airliquide.de/sdb/acetylen.pdf
I have only the german version, see "15. Vorschriften" (Page 2), R5 and R6:
In English:Quote:
R 5 - Beim Erwärmen explosionsfähig.
R 6 - Mit Luft und ohne Luft explosionsfähig.
R 5 - when warming up combustibly.
R 6 - with air and without air combustibly.
I found English Version:
http://www.airliquide.com/safety/msds/en/001_AL_EN.pdf
See: 15 REGULATORY INFORMATION, - Risk phrases, R5 and R6:
Quote:
R5 - Heating may cause an explosion.
R6 - Explosive with or without contact with air.
If you'll read that document (or some other on airliquide) you will find also that acetylene is incompatabile with copper - decomposes. Funny your torch has some copper.. ? (no pune intended)
Any high pressure gas (and acetylene IS one of them) can explode beacause of the pressures involved.
Where did you read that?
I only saw this:
Quote:
Forms explosive acetylides with copper, silver and mercury. Do not use alloys containing more than 70% copper.
What means pune?
8psig Acetylene and 36psig Oxy? Oxy setting is way to high for that little tip your using IMO.
Does that joint crack when you bend the pipe? Looks like you over heated it.
36psi = 2.5 Bar, or?
2.5 Bar is indicated on the tip. I reduced it to 20psi, no big difference but also ok for brazing.
None of my connections ever cracked when bending. But its not easy to take pics and braze... i only have 2 hands :/
18bar full, does that mean all acetylene bottles? I think that the one i have at home has 40bar in it when full.
Those flamebarriers, can you fit them on old equipment aswell?
Quote:
Originally posted by berkut
This is a very nice guide, deserves a sticky...
Yes that is true, but how long do you have it on ? Maybe 1 second ? Later the oxygene rich gas flow will oxidize the soot as you called it
Tell me something about it :D This is dangerous in a hands of a noob...
I start my torch this way:
-tip pointing away from me ;)
-start mapp/acetylene
-fire it up with a 2nd torch or special tool
-turn oxygene on
this is a safer way of doing it.
when brazing a evap watch out not to push the tip of the torch too close to the evap, i had a accident when the evaporator filled up with oxy/mapp and exploded (the shockwave comming out of the sucktion line would burn my face if i havent had my welding mask on, gloves etc., yes i do such stuff in a welding mask, much safer)
When describing how to braze we should start with the dangers of using a torch. I think we should point out some stuff as well as give some tips.
i learn this in year ten and we did it this way too.
i use to love making it pop scaring everyone
and heat up the flint and bang it on the brick and watch it explode
18 Bar for the "new" Bottles. Acetylene therein is solved in acetone.Quote:
Originally posted by Pandrone
18bar full, does that mean all acetylene bottles? I think that the one i have at home has 40bar in it when full.
Those flamebarriers, can you fit them on old equipment aswell?
If you want to use a flamming barrier for your setup consider your local reseller. The one i use are for 3/8" (Acetylene) and 1/4" (Oxigen).
Quote:
Originally posted by Sidewinder
18 Bar for the "new" Bottles. Acetylene therein is solved in acetone.
If you want to use a flamming barrier for your setup consider your local reseller. The one i use are for 3/8" (Acetylene) and 1/4" (Oxigen).
What did those flamebarriers cost? (i know it's not the same price here in sweden) but just so i have a hint of the price :).
Flamming Barriers are a one-time-use product. When they reacted they are Rubbish, so they are pretty Cheap. I payed 18€ for one.
Thanks pc ice :)
You can call me Side dude :P
and also thanks to fugger :)
berkut, to use acetylene-oxygene torch in Poland, any certifications are needed?
Aye, acetylene run through copper develops (over time) a deposit that is impact explosive, ie, if you drop it, it goes BANG! :p
I did a six month welding course, and we were tought to light the torch with just acetylene running, then feed in the oxygen to get the required flame.
If you are having trouble finding info on flame barriers, try searching for 'flash back protectors' :)
Hmm... in germany you have to open oxigen and acetylene first and then light it... Launching Acetylene first is nearly forbidden Oo
damn that were its name :/Quote:
If you are having trouble finding info on flame barriers, try searching for 'flash back protectors'