Product Range

Variable Area
Flow Meters
Type 335, Type 350
Short Version
Product Range Special Version

Benefits
Variable area flow meters �?a reliable, accurate and economical
measuring principle.
Variable area flow meters from GF Piping Systems are radially installed dismountable meters for flow measuring in
industrial piping applications. The measurement ranges, which are attuned to our customers�?needs, and the range of
materials available for the tubes and connection ends, mean that the flow meters can be used for a wide range of
applications and a great variety of media.

Measuring principle - Three main forces act on the float
• The weight G
• The buoyancy A
• The flow force K
Main advantages
• The flowmeters require no auxiliary power
• Cost effective to measure the flow rate
• Break-proof and corrosion-resistant
• Accessories like sensor 4-20 mA and limit contacts
• Guiding rod from DN50 for stabilisation of float within v
• Low pressure loss
• Can be used for liquids and gases
• Volume- and % scale as standard
Segments
• Water Treatment
• Chemical Process Industry
• Microelectronics
• Food & Beverage
• Ship Building
• Building technology
• And many more

Features
Know your flow
All the flow meters are equipped with a double scale: a percentage scale as well as a scale for the flow volume in l/h
for water (H2O). Special scales are on offer for m³/h, GPM, in addition to special graduations for HCL, NaOH, air and can
be affixed on taper tubes without scales subsequently. Measuring accuracy falls in the accuracy class 4 according
to VDE/VDI 3513 Part 2.

Install and remove radially
with threaded joint
Wide dovetail guide for easy
fastening of limit switches
One limit switch each for
min. / max. flow (optional)
Transparent taper tube
in a variety of materials
Insert with damping
feature for float in case
of water hammer
Flow immediately
visible with setpoint
indicators
Imprinted double scale
for water in percent (%)
and flow volume (l/h)
Orange-colored PVDF
float makes it easy
to read the flow
Fast connection with
standardized cement socket

System details
The float measuring principle �?accurate flow measurement of liquids
and gases.
Before installing
1. The pincer-like transport lock must
be removed. To do this, the upper
union nut is unscrewed and the
upper insert including seals is
removed. Double-check the taper
tube and if available the guiding
rod on damages caused due to
shipping.
2. Then the VAFM must be reassem
bled.
3. The piping system into which the
VAFM is installed must be in a
vertical position to ensure its
functionality.
4. An inlet and outlet section must
be provided for (inlet ca. 10 x DN,
outlet ca. 5 x DN).
Accessories
Due to the integrated dovetail shaft it
is possible to mount further accesso
ries like 4-20 mA flow sensor GK15 or
limit contacts GK10/11.
Accurate reading
The top edge of the float indicates
the flow volume. If special scales are
applied subsequently, it must be
ascertained that the scale marking
EF is affixed congruently with the
one on the taper tube.
Installation lenghts and materials
The variable area flow meters are
now available in the installation
lengths 335 mm, 350 mm, 200 mm,
185 mm and 165 mm. The taper tubes
are available in Polyamid, Polysulfon
and transparent PVC-U. The standard
floats are in PVDF with or without
magnet. The end stops are in PVDF.
The threaded joint including insert is
available in PVC-U, as well as in PP,
PE or ABS on request. The O-rings
are made of EPDM or FPM.
The nominal pressure is 10 bar
at 20°C.
If a medium flows upwards at a sufficient rate of flow
through the vertically mounted taper tube, the float
is raised to the point at which a state of equilibrium
sets in between the lifting force of the medium and the
weight of the float. Since the mean rate of flow is
proportional to the quantity flowing through per unit
of time, this state of equilibrium corresponds to the
measurement of the instantaneous flow rate.