model G gas proportioner meter

model G multi gas flow meter for low flow rate gas blending and measurement

Design Features

blending of two or three gases with gas proportioners obviates the need for:
- ordering fixed gas mixtures
- contamination from reusable gas cylinders
- potentially inaccurate mixtures by gas suppliers
rib-guided or fluted metering tubes facilitate stable/accurate readings
magnifier lens in front shield to enhance reading resolution
interchangeability of flowtubes and floats
OPTIGRAD™ scales minimize parallax and eye fatigue
simple means of panel mounting

Blending two or three gases in homogeneous infinitely variable concentrations directly at the end use point, this model G gas proportioner is unsurpassed in convenience and economy. Gas proportioners pay for themselves since they eliminate the need for expensive custom blended gas mixtures. They lend flexibility and economy to the utilization of component gas cylinders and “piped-in” supply lines.

Another advantage in laboratory investigations is the freedom to reproducibility increase or decrease concentrations during the course of an experiment.

The flowrates are not affected by downstream pressure variations as long as back pressures do not approach or exceed the input pressure. Input pressures of up to 200 psig (13.8 bars) can be used; however, customers very often find 50 psig (3.45 bars) a convenient setting to work with.

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BUILT-IN VALVES

Meters are available with built-in needle valves (CV™), high precision metering valves (MFV™) with “non-rising stems”, or with no valves. The higher cost of MFV™ valves is justified whenever high sensitivity control and resolution are desirable particularly in conjunction with metering tubes of very low flowrates.

SPECIFICATIONS [standard component]

STANDARD ACCURACY ±2% FS (mm scales) except 032/042 flow tubes ±5% FS

CALIBRATED ACCURACY ±1% FS

REPEATABILITY ±0.25% FS Typical calibration curves for air at 50 psig/3.5 bars using glass floats are available. Consult with Aalborg on the availability of calibration data for non-hazardous gases and special individual calibrations.

USEFUL FLOW RANGE 10:1 minimum with one float and better than 20:1 with combination of two floats installed in meters

MAXIMUM OPERATING PRESSURE 200 psig (13.8 bars)

MAXIMUM OPERATING TEMPERATURE 250°F (121°C)

MATERIALS OF CONSTRUCTION

FLOW TUBES heavy walled borosilicate glass

FLOATS glass, sapphire, 316 stainless steel, carboloy and tantalum

CHOICE OF MOUNTING FITTINGS IN CONTACT WITH GASES

aluminum, black anodized
316 stainless steel

SIDE PANELS aluminum, black anodized

FRONT SHIELD 1/8 inch thick clear polycarbonate

BACK PLATE 1/8 inch thick white acrylics

O-RING and PACKING Buna-n o-rings standard in aluminum models; Viton® o-rings standard in stainless steel models; optional Viton®, PTFE/Kalrez®, EPR

CONNECTIONS 1/8 inch NPT female inlet and outlet connections; optional 1/4 inch FNPT, hose and compression fittings are available

VITON® and KALREZ® are registered trademarks of DuPont Dow Elastomers