All Hedland variable area flow meters use a sharp-edged annular orifice, formed between the open-centered piston and a contoured metering cone. The piston is held in a “no flow” position at the base of the contoured cone by a calibrated retention spring. Flow through the meter creates a differential pressure across the piston orifice, moving the piston against the spring. The greater the volume, the further the piston moves. Externally, the flow indicator is magnetically-coupled to the moving piston. The indicator is visually “read” against a graduated flow scale.
The Hedland Flow Meter for Water-based Fluids are low-cost, yet rugged variable area flow meters. These in-line flow rate indicators are industrial class and can be used in high-temperature water-based fluids and emulsions. These Hedland flow meters feature quality metal construction in aluminum, brass, or stainless steel. You can choose from six port sizes from 1/4″ to 1-1/2″.
These variable area flow meters can be used in applications in which the temperature ranges from -20 to 400°F (continuous) and 400 to 500°F (intermittent). Stainless steel flow meters are pressure rated for 6,000 psi/414 bar maximum (5,000 psi/345 bar maximum for 3/4″ to 1-1/2″ series) with a 3:1 safety factor. Aluminum and brass flow meters are pressure rated for 3,500 psi/241 bar maximum with a 3:1 safety factor. Brass models are highly recommended for water systems or for systems where galvanic corrosion may be a problem.
The Hedland Flow Meter for Water-based Fluids has a flow range from 0.1 to 150 GPM.