How They Work
Fluid enters the inlet of the metering tube exerting a force on the float. As the force overcomes the weight of the float, the float rises in the tube. When the forces of gravity, float weight, and the fluid force reach an equilibrium, the float stabilizes in the tube. The position of the float at equilibrium corresponds directly to the flow rate. The flow rate is indicated on a scale etched directly onto the metering tube. This scale may be either a direct reading scale or a reference scale. A reference scale requires the use of a calibration data chart.

Variable area flowmeters must be mounted vertically with the flow moving upward through the metering section to assure accuracy. Within this restriction, they offer the flexibility of being bench-mounted or mounted directly in a pipeline, control panel, bypass system, or backup system for electronic controllers.

Description
Aneer Engineer’s flowmeters feature an easy-to-read scale, permanently etched onto a heavy glass flow tube. This scale permits measurement of a wide range of gases and fluids under a variety of pressure and temperature conditions.
Each flowmeter is equipped with two, panel-mount retaining nuts for easy industrial panel mounting or with an optional tripod base for easy bench setup in laboratory applications. Pipe-to-tubing or pipe-to-hose adaptors are also available.

150 mm Flowmeter Tube
Because of its superior resolution, this flowmeter tube is recommended for laboratory applications. Accuracy is ±2% scale with ±.5% repeatability. The elongated scale permits critical flows to be gauged more accurately and read more easily. Conversion charts for air, argon, carbon dioxide, helium, hydrogen, nitrogen, and oxygen are supplied with each unit.

Materials of Construction
Materials of construction are an important consideration. End fitting materials are available in brass, stainless steel, and Teflon material. Brass units may be used with inert and noncorrosive media. Stainless steel and Teflon units are recommended for nontoxic, corrosive service applications.

Gas Conversion Factors
To find flow for gases other than air, multiply the flow rate values for air by the applicable conversion factor.