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.
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 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
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| 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 |
