Hedland Positive Displacement Flow Meters

Hedland,Variable,Area,In-Line,FlowmetersThe Hedland product line includes over 7,000 in-line variable area type flow meters, designed to monitor oil, phosphate ester, water and water-based emulsions, air and other compressed gases. Hedland offers flow meters constructed of high-performance materials including: Anodized Aluminum, Brass, and Stainless Steel. The Hedland meters are easy to install, operate in any position (no flow straighteners or special piping needed) and are accurate to 2% of full scale.

Aluminum meters are offered as a rugged, low cost flow meter for monitoring non-corrosive water-based or petroleum-based fluids in flow ranges up to 300 GPM (1100 LPM) and pressures up to 3,500 psi (241 bar).

Brass models are recommended for water systems or other applications where galvanic corrosion could become a problem. Brass meters are rated to withstand pressures up to 3,500 psi (241 bar), and are available up to 150 GPM (560 LPM).

For higher pressure systems we recommend our T303 Stainless Steel models, and for corrosive or caustic fluids, we recommend our T316 Stainless Steel meters. These meters can withstand pressures up to 6,000 psi (414 bar) with flow ranges up to 150 GPM (560 LPM).

The standard flow scale for liquids is calibrated in GPM and LPM at .876 specific gravity for petroleum, 1.18 s.g. for phosphate ester, 1.0 s.g. for water and water-based emulsions, 1.0 s.g. for air and compressed gases. Special scales are also available in other units of measure or specific gravities. The pneumatic meters are offered with a unique multi-pressure flow scale, calibrated to indicate flow rate, in standard cubic feet per minute (SCFM), or liters per second (LPS), at various pressure from 40 to 130 psi (3 to 9 bar)

The Hedland flow meter is a variable area instrument. A precision machined, sharp-edged orifice located within the piston assembly, forms an annular opening with the contoured metering cone. The piston assembly carries a cylindrical PPS/Ceramic Magnet that is magnetically coupled to an external Flow Indicator that moves precisely, in direct response to movement of the piston. A calibrated Spring opposes flow in the forward direction This spring decreases viscosity sensitivity and allows the flow meter to be used in any position, including inverted.


General Design Features

Bi-directional flow capability: If required, a reverse flow bypass option is available and is depicted on individual product pages. Note that flow is measured in the forward direction only.

Operates in any position: The Hedland In-line flow meter’s unique spring loaded variable-area design allows meters to be installed in any position without affecting accuracy. An optional inverted flow scale is also available.

Easier to read linear scale: This flow meter is the most readable product in its class. Brightly colored indicators move over the graduated, linear Flow Scale which contains bold, easy to read numerals and gauge marks. This enhanced This enhanced resolution filely eliminates parallax problems associated with competitive, direct reading flow meters.

360 Rotatable guard/scale: Hedland’s unique design allows the meter to be installed in any orientation without regard to scale direction. Once the meter is permanently installed, the guard/scale can be rotated 360 to optimize readability.

Rugged construction: Flow meters are available in anodized aluminum, brass, T303 and T316 stainless steel, with SAE, NPTF, BSPP, and Code 61 and Code 62, 4-bolt flanged ports. This easy-to-read flow meter is a reliable and trouble-free flow rate indicator, monitoring a variety of liquids and gases (including aggressive chemicals) under a wide range of pressures, temperatures and rigorous conditions encountered in industrial applications.

No flow straighteners or special piping: The Hedland design does not require special plumbing or accessories to stabilize turbulent flow. Flow meters can be installed immediately adjacent to 90 degree els or other components to provide greatest system design flexibility, while saving installation time and money.

Relatively insensitive to shock and vibration: This unique design is inherently less sensitive to shock and vibration that other variable-area flow meters. The new, improved coupling forces between the internal and external magnets greatly reduce the chance of de-coupling the flow indicator under high flow and pressure transients. The magnetic coupling also eliminates the need for mechanical linkages that wear, loosen and leak over the functional life of competitive meters.