The
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.
