Regulated Flow Meter (for CO2)
After buying a 15 lbs CO2 tank from a local fire extinguisher place, I
have been searching for a good regulator and needle valve combination
that's not too expensive. What I found was that any good two-stage dual
gauged regulator used for welding cost anywhere between C$75 and C$160.
I was also unable to find the fixed pressure FROG unit mentioned in the
FAQ. I understand it doesn't have any gauge which is something I like to
have. In terms of needle valves, the one George Booth recommended (Nupro
B-4MG2) looked very solid but its C$59 cost is a bit expensive (why am I not
surprised :-)). I also considered getting just a heavy duty valve, like
the Parker valve suggested by Jamil Zainasheff, without the use of a
regulator, but again I wanted to have something that had a gauge to tell
me when the tank is about to go empty etc.
Finally I found a gaget called a Regulated Flow Meter which is essentially
a regulator with an integrated needle valve control plus a flow rate gauge
in units of CFH (Cubic ft per hour?). Although the flow rate gauge is not
that useful for our purpose, I found that the integrated flow control is
very smooth and precise. I can get exactly one bubble per second without
doing much adjustment. It is rated for 3000 psi. There is also a
round dial gauge that gives you the pressure (PSI) inside the tank. The
whole thing is made of solid brass.
If you are interested, this thing is made by Victor Equipment Company of
Denton Texas, model # HRF1425-580. I paid C$90 for it, cheaper than a good
regulator+separate valve. And you don't have to look for different
connector and hoses to connect the two. That's about US$65 at the current
exchange rate. It may be cheaper in the States, especially if you have
better welding contacts than I do.
John Y. Ching (jyching at watnow_uwaterloo.ca) |
Pattern Analysis and Machine Intelligence Lab |
Department of Systems Design Engineering |
University of Waterloo, Canada |