Low Nitrogen flow while brazing - How to regulate?

My Linde Nitrogen purging regulator doesn't regulate pressure to well below about 25 PSI. Other then buying a low flow setup how do you all keep a very low Nitrogen purge flowing while brazing linesets.
If you dry fit all the lineset connections and give it a good Nitrogen purge and then shut off the flow will the residual Nitrogen keep the Oxygen from invading. Nitrogen is only one notch lighter then Oxygen so I don't think it's going to get too anxious to escape.
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pv=nrt wrote:

when you fit up the copper, wrap each joint with one wrap of electrical tape, being careful not to get the tape hot enuf to melt if welding nearby. peel the tape before welding the joint
then crank the nitro reg down to its lowest point possible and still get a flow. if i need finer control, i'll run it thru the low side on my guage set and then crank it down to 1 psi or less.
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pv=nrt wrote:

systems. I use it also to slow down the flow of nitro. through pipes. The regulator can be set up to a higher pressure to keep the flow going and the restrictor keeps the flow down. Stormy Weather
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I replaced our Airco regulator for a new Goss, WHAT A MISTAKE! The Goss is a real POS.
I will never buy another Goss for anything since this last regulator.
Rich
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small piece of quarter inch copper onto one end. Next, put a quarter inch flare nut on the end, use a flare union and your refrigeration gauge set, hook your gauge set to your nitrogen regulator and there you go with you .5 to 1 PSI nitrogen flow.
Barry

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wrote:

Hey, that's a great idea!! I was thinking of ways of restriction but I didn't want to have a situation where high excessive pressure would blow out or expand my hoses, this prevents this from happening since the regulator itself has a relief, but we all know that it could release after we expand the hoses. What diameter cap tube in your experience would you say works well? Man, I like this idea......
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