Gow-Mac 580 series, Руководство по эксплуатации

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GOW-MAC Instrument Co. 22
11. Once leaks have been located and stopped, return the instrument to operating condition:
bleed all pressurized lines to atmospheric pressure; remove Tygon
®
tubing at OUTLET
PORTS.
K. Gas Flow Adjustments
The GOW-MAC Digital Flowmeter for non-corrosive gases, part no. 180-567, is recommended
to set the carrier gas fl ows. Attach fl exible tubing to Outlet “A” on the GC and adjust the fl ow rate
with the metering valve on the front of the instrument. Proper use of the Digital Flowmeter can be
assured if used within the parameters set in its’ accompanying manual.
1. Turn on gas supply at cylinder.
2. Pressure settings depend upon the particular column(s) being used. Pressure MUST be at
least 15 psig to activate the safety switch. Thirty (30) psig is adequate for most columns. Fifty
(50) to one hundred (100) psig may be required for longer 1/8” packed columns (10’ or
longer).
3. A bubble type fl owmeter can also be used with a stopwatch. Gently squeeze the reservoir of
the fl owmeter until a stream of soap bubbles emerge. Allow several bubbles to rise and wet
the sides of the glass meter. START the stopwatch when a bubble reaches the “0” mark on
the meter. STOP the stopwatch when the bubble reaches the “10” mark on the meter. The
elapsed time, in seconds, for the bubble to rise from “0” to “10” divided INTO 600 equals the
fl ow rate in mL/min. Adjust SIDE “A” FLOW CONTROL VALVE for the desired rate (usually
60 mL/min.).
600 = fl ow rate (mL/min.)
sec.
NOTE
)
BEFORE MEASUREMENT, ALLOW AT LEAST ONE MINUTE
BETWEEN EACH ADJUSTMENT FOR THE RATE TO EQUILIBRATE.
4. Change the fl owmeter to OUTLET PORT “B” and repeat Step 2, above, for the desired rate
(usually 60 mL/min. for 1/4” columns or 30 mL/min. for 1/8” columns).
5. The fl ow rates have now been adjusted. Disconnect the fl owmeter.
OUTLETS
A
B
10 mL
0 mL
Figure 3-3
Gas Flow Adjustments Using a Bubble-type FLowmeter