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icecube51
27-07-2009, 05:48 PM
Hey Guys (and girls),

just wondered how you good folks set up the nitrogen equipment before and during the actual welding.

i connect the nitrogen hose on one end of the line,and connect a second hose on the other end of the line that needs welding.
than i keep the end of the second hose in a bottle of water and open the nitrogentank just enough to when there are bubles in the waterbottle.
thats tells me there is a constant flow,and also if the nitrogen tank is empty.
its cheap,but works fine for me.

Ice

Clk320_Greg
27-07-2009, 06:21 PM
Hey Guys (and girls),

just wondered how you good folks set up the nitrogen equipment before and during the actual welding.

i connect the nitrogen hose on one end of the line,and connect a second hose on the other end of the line that needs welding.
than i keep the end of the second hose in a bottle of water and open the nitrogentank just enough to when there are bubles in the waterbottle.
thats tells me there is a constant flow,and also if the nitrogen tank is empty.
its cheap,but works fine for me.

Ice


Not sure i would be dipping hoses in water, i normally connect it to one end, wind the reg upto about 50PSi, then used a hose with a tap on it, open it enought to allow a little flow (you can hear the flow at the other end and or lick you finger and hold it at the end and you will feel it) and weld. leave the OFN flowing while i cool the joint then off with the OFN and seal both ends!

morgan c
27-07-2009, 09:25 PM
would'nt use water bottle either jst attach hose to pressure regulater,turn handle,i either hold hose to my ear or feel with my hand for desired pressure. all done safely of course.

monkey spanners
27-07-2009, 10:16 PM
Ive got one of those gas flow thingies with a bead in a glass tube, the more flow (adjustable with a knob) the higher the bead goes, same as used on a mig/tig welder. was only about £20

Peter_1
28-07-2009, 08:03 AM
..., i normally connect it to one end, wind the reg upto about 50PSi, ...

You have pressure regulators and flow regulators, you're using a pressure regulator which spills a lot of N2.
After doing +/- 70 sessions for the F-gas exams, we've found out you spill more than 300% with a pressure regulator.

lowcool
28-07-2009, 01:26 PM
regulator and flow meter otherwise you can forget about the adaptor sitting with bottle pressure(suicide fitting)been there done that

icecube51
28-07-2009, 05:20 PM
when i connect the hose to the nitrogen tank,i have a pressure regulator in between. and if i let the other end in the plastic bottle,the hose is about 5mtr long. so capillarity of H²O is out of the question. i did check t out the consumption Peter_1, and at the moment my system is cheaper on nitrogen. and i am also sure that there is always a constant flow, i notice directly when the NGO tank is empty.

Ice

Clk320_Greg
28-07-2009, 07:06 PM
You have pressure regulators and flow regulators, you're using a pressure regulator which spills a lot of N2.
After doing +/- 70 sessions for the F-gas exams, we've found out you spill more than 300% with a pressure regulator.

What do you mean by spill? Yeah the reg on top of the OFN bottle is a pressure one, but surely the tap i use acts as a flow reg, and pressure reg just drops the pressure to the tap?

Or like i confused dog do i have the wrong end of the stick?

Peter_1
28-07-2009, 10:01 PM
Both have a pressure reducer but a pressure regulator regulates the outlet to a certain pressure (psi of bar which you don't need for soldering) and a flow regulates for a certain flow (l/min)
Both look similar (analog dials) but the working principle isn't.http://www.germes-online.com/direct/dbimage/50208489/Regulator_and_Flow_Meter.jpg

As soon you blank of, a flow regulator will stop where a pressure will build up. A flow of 5 to 10 l/min is enough.

What I mean with a spill: we needed the first exams 1 bottle OFN for every 3 brazing tests with pressure type. Now we can +/- 7 exams with 1 one bottle with a flow type. The flow type is even obligated for the exam centers now in Belgium when you do the brazing tests.

TIG welders always use a flow type.

monkey spanners
28-07-2009, 10:34 PM
Mines like AR-101-2, you can set the flow by how high the bead goes in the tube.

Jon

WaterholeWally
29-07-2009, 02:49 PM
I keep an assortment of mostly clear plastic tubes (hoses) in a milkcrate with all my nitro goodies. I slide a tube on the one end and clamp it with a springclamp. It holds on by itself for light flow, and blows off with too much flow. Since, I've been doing this, I've noticed much less nitrogen use. Works for me!!!
Wally

carlfoster
29-07-2009, 11:13 PM
Can I ask what welding we're talking about here? Is this ordinary pipe brazing?

oportobonito
10-09-2009, 09:33 PM
Hi,
I am a new member and I would ask that how the liquified nitrogen gas preserved without being empty

Thanks

I need

Brian_UK
10-09-2009, 10:29 PM
Can I ask what welding we're talking about here? Is this ordinary pipe brazing?
Yes it is brazing.

Brian_UK
10-09-2009, 10:29 PM
Hi,
I am a new member and I would ask that how the liquified nitrogen gas preserved without being empty

Thanks

I need
At extreme low temperature or in a pressurised cylinder.

steele3923
04-10-2010, 02:43 AM
we installed a new walk in freezer w/404a. line set is about 8 feet long from cond to evap w/ about 12 joints brazed . after about 3 hrs the txv shut down i told the tech it might b from not using nitro while brazing all the pipe. dpoes anyone agree with me????