Argon regulator/flowmeter will work fine for Argon / Helium / Nitrogen gases.. They all use the same threaded connection to the cylinder....cga-580
There are nitrogen regulators that have a flowmeter but they are expensive.
Like you mentioned, just have to take into account the flowmeter conversion for Nitrogen.
I think when using Nitrogen in an Argon flowmeter, the conversion is 1.19...so not much difference.
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Most of the flowmeters in the USA are show in units of SCFH standard cubic feet per hour
15-20 liters per minute = 32-42 scfh
So using an Argon flowmeter with Nitrogen gas, the conversion is 1.19.
Argon is heavier than Nitrogen. I thought more than what these conversion tables state, oh well.
So for 20 lpm or 42 scfh of Nitrogen......the Argon flowmeter would read: 42 scfh/1.19 = 35 scfh
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Sometimes the same flowmeter with have units on it for CO2
Same conversion for using Nitrogen......except conversion is 1.26 in this case.
42/1.26 = 33 scfh
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