Variable-area flow meters

Hedland flow meters are variable area instruments – as the hydraulic oil or compressed air enters the meter, it is directed around a contoured metering cone located within the piston assembly.

The pressure differential created by the flow around the cone causes the piston to move against the spring. The piston assembly carries a cylindrical PPS/Ceramic Magnet that is magnetically coupled to an easy-to-read linear flow scale that moves precisely, in direct response to movement of the piston for a quick visual indication to confirm systems are operating correctly.

Hedland flow meters are manufactured from aluminium, brass or stainless steel and are accurate to ±2% of full scale, their rugged construction enables them to work under a wide range of pressure (up to 6000 psi/414 bar), temperatures (260°C/500°F) and rigorous conditions encountered in industrial applications.

The meters are also inherently less sensitive to shock and vibration than other variable area flow meters and the magnetic coupling also eliminates the need for mechanical linkages that wear, loosen and leak over the functional life of a typical variable area meter.