INTRODUCTION TO FLOW METERS
What are Flow meters
A flow meter is an instrument used to measure linear,
nonlinear, mass or volumetric flow rate of a liquid, steam or a
gas.
Selecting a Flow meter
The basis of good flow meter selection is a clear
understanding of the requirements of the particular application.
Evaluating the nature of the process fluid and of the overall
installation.
Innovative Technologies, Creative Solutions
Quality & Simplicity in Flow Measurement
SELECTING A FLOW METER
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Key questions which need to be answered before selecting a flow
meter:
What is the fluid being measured by the flow meter.
Do you require rate measurement and/or totalisation from the flow
meter?
What viscosity is the liquid?
Characteristics of the fluid (Is the fluid clean, have particles?)
Do you require a local display or do you need a signal output?
What is the minimum and maximum flow rate ?
What is the minimum and maximum pressure?
What is the minimum and maximum temperature?
Is the fluid chemically compatible with the flow meter ?
If this is a process application, what is the size of the pipe?
FLOW METER SELECTION
How To Select a Flow meter
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Line Size – Do not choose meter on line size.
Flow Range – Same size meters can have totally different flow
ranges.
Fluid Compatibility – Check meter materials of manufacture
are compatible with fluid.
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Viscosity –Flow de-rating factors or limits may apply.
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Connections –Pressure rating of meter flanges.
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Protection – Choose correct mesh size for strainers.
Accuracy & Repeatability – Repeatability is the more
important parameter
TURBINE FLOW METERS
The turbine meter normally has an accuracy
of 0.5% of the reading. It is a very
accurate meter and can be used for clean
liquids and viscous liquids up to 100
centistokes. A minimum of 10 pipe
diameters of straight pipe on the inlet is
required. The meters consists of a multibladed rotor mounted at right angles to
the flow and suspended in the fluid stream
on a free-running bearing.
PADDLEWHEEL SENSORS
One of the most popular cost effective
flowmeters for water or water like fluids.
Many are offered with flow fittings or
insertions styles. These meters like the
turbine meter require a minimum of 10
pipe diameters of straight pipe on the inlet
and 5 on the outlet. The rotor of the
paddlewheel sensor is perpendicular to
the flow and contact only a limited cross
section of the flow.
POSITIVE DISPLACEMENT FLOW
METERS
Oval Gear
Rotary Piston
Positive Displacement meters come in
various configurations & are a very
versatile flow meter, best suited for
high viscosity & non–conductive
liquids. They have high accuracy
(linearity & repeatability) with low
flow and precise batch capability.
Meter requires no flow conditioning
for simple installation and are easy to
understand & service.
OVAL GEAR FLOW METERS
Positive Displacement
Oval Gear Flow Meters
OVAL GEAR FLOW METERS
GEAR WHEEL FLOWMETER
Among the many Positive
Displacement flow meter
design principals available
today, the oval gear wheel still
holds a top place in simplicity
& field proven performance.
OVAL GEAR FLOW METERS
OPERATION OF OVAL GEAR FLOW METER
OVAL GEAR FLOW METERS
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Trimec Flow Products Oval Gear Wheel meters provide high
levels of accuracy & repeatability for a wide range of clean
liquids irrespective of viscosity & conductivity either pumped
or gravity fed.
OVAL GEAR FLOW METERS
General Specifications Oval Gear Flow Meters
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Flow range:
Nominal sizes:
Linearity:
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Repeatability:
Temperature:
Materials:
Pulse outputs:
Mechanical Displays:
0.5 litres / Hr ~ 2500 litres / min.
4mm ~ 100mm pipe size
+/- 0.5% of reading ( +/- 0.2% with
linearisation )
( +/- 1% for Mechanical Displays )
+/- 0.03%
-20 ~ +120 Deg C - Standard
aluminium or 316 stainless steel
reed & NPN open collector
3 ,4 & 5 digit
OVAL GEAR FLOW METERS
Meter Features
Optional Rotor Material - on
BENEFITS
all meter sizes
( excludes extended flow versions )
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Rotor Stability
( On Metal Rotors )
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120 Deg. Temp. Rating.
( High temp rotors not required )
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Aluminium, Ryton & Stainless
Steel materials.
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Metal Roller, Carbon or
Ceramic Bearings.
OVAL GEAR FLOW METERS
Meter Features
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Modular Process
Connections
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Available on 25mm to
100mm meter sizes.
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Simplifies Installation
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Screwed or Flanged
connections.
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Stainless option on
screwed versions.
OVAL GEAR FLOW METERS
Meter Features
Pulse Output Boards
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Dual Outputs ( reed &
Hall ) Standard.
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Quadrature Pulse Output
Option.
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Pulse Interrogation
connection
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High Pulse Output option
( Hall only )
OVAL GEAR FLOW METERS
Meter Features
Low & High Flow Capabilities
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Broad Range 1/8” to 4”
0.5 LPH to 2500 LPM
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High Precision +/- 0.5%
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Optional +/- 0.2% with linearization
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Unaffected by pulsations
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No Flow Conditioning
required
OVAL GEAR FLOW METERS
Meter Features
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Available as pulse meter only or with integral or remote mount LCD or
mechanical registers.
Dual Outputs ( reed & hall) as standard.
Weatherproof IP66 / 67 LCD models
Flameproof / Explosion proof construction Atex & IECeX
Intrinsically Safe Integral Instruments.
Modular connections for adaptability and ease of installation and service.
Quadrature pulse output option for pulse verification or forward / reverse
measurement.
High Flow Capabilities ( 2500 lpm )
NMI Certification ( Resale Purposes ) meter sizes 1” to 4” fitted with air
eliminator strainer and approved register.
OVAL GEAR FLOW METERS
Meter Features
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High Precision / High resolution ( Pulses per Litre )
120 Degree Temperature Rating as standard.
High & Low viscosity applications.
3 , 4 or 5 digit Mechanical Registers with large number
displays. ( Metal Housings with or without accuracy adjustment )
Gearbox fitted with stainless steel gears as standard.
Aluminium rotors fitted with high speed roller bearings.
Stainless rotors fitted with ceramic or carbon bearings.
Ryton Rotors
Viton seals as standard.
OVAL GEAR FLOW METERS
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Meter
Features
Advantages
Metal & Plastic Rotors
Modular Connections
Higher Temperatures -120deg
Higher Flows 25mm size – 150 lpm
Larger Flow Range – 2500 lpm
More Models – Extended Capacity
Ductile Iron material
ATEX & IECex approvals
NMI approval Mechanical Meters
Accuracy Adjustment – Mechanical
Viton seal standard
Electronics – own manufacture
Gearbox – stainless gears
Large size reset number display
Opposition
Metal & Plastic
Cast in meter body
80 deg.
120 lpm
1200 lpm
N/A
N/A
N/A
N/A
N/A
Nitrile
Fluidwell / Flux
Plastic Gears
Small reset numbers
OVAL GEAR FLOW METERS
Meter Specifications:
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Low Pressure Drop standard feature.
Extended Flow Models available in 2”, 3” & 4” sizes.
Factory calibration & accuracy certificate supplied.
Flexibility of Installation. ( vertical or horizontal lines )
Min. number of moving parts in LCD pulse meters ( 2 Rotors )
Continued product development commitment.
Standard Meter – Pulse Output
Options ~ LCD Register
~ Mechanical Register
~ Batching Register
OVAL GEAR FLOW METERS
Meter Specifications:
Minimum number of moving parts in pulse meters
2 Rotors
Reed
Switch
OVAL GEAR FLOW METERS
Meter Selection
 Meter max. flow rates are based on 1 bar pressure drop
 With Fluids above 1200 cps. Meter sizing and required flow rate
become important decisions.
 To achieve the lowest possible pressure drop, a range of special cut
“ Keishi” high viscosity optional rotors are available.
 The Dimak series oval gear meters are extremely suited to
measuring highly viscous materials with the pressure drop being
the only limiting factor.
 Special rotors applies to meters sizes TF-008 to TF-100 also refer
to de-rating factor for reduced flow rates applicable
OVAL GEAR FLOW METERS
VISCOSITY CORRECTION
Flowmeters
Depending on the fluid
viscosity the flow meters
maximum flow rate may be
de-rated according to the
attached chart.
Example:- TF25 meter
measuring oil @ 6000 Cp
Max Flow 150 lpm x 0.5 =
75 lpm new maximum flow
rate to maintain 1 bar
pressure drop.
OVAL GEAR FLOW METERS
VISCOSITY
Oval Gear Rotor
Special Cut Rotors:
Above 1200 cps.
Every 3rd Tooth
Removed
OVAL GEAR FLOW METERS
Accuracy & Pressure Drop Curves
FLOW INSTRUMENTATION PRODUCTS
FBT11 Battery Powered Totaliser
REMOTE OR INTEGRAL METER
MOUNT
Simultaneously displays re-settable
(batch) total in engineering units as
programmed by the user. When externally
dc powered the instrument will produce an
un-scaled or scaleable solid state output
pulse which is NPN / PNP selectable.
FLOW INSTRUMENTATION PRODUCTS
FRT12 Flow Rate Totaliser
REMOTE or INTEGRAL METER
MOUNTING
Simultaneously displays re-settable
(batch) total & cumulative total in
engineering units. When externally dc
powered the instrument will produce an
un-scaled or scaleable solid state output
pulse which is NPN / PNP selectable.
FLOW INSTRUMENTATION PRODUCTS
FRT-40 Flow Rate Totaliser
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REMOTE or INTEGRAL METER
MOUNTING
Battery or External powered, 6 digit large
LCD total & 8 digit cumulative totaliser,
with 5 digit rate display.
IP66/67 ~ Nema 4X aluminium housing.
LCD Backlighting as standard.
Scaled Pulse Output.
Optional facia protection shield
Metal Housing as standard
FLOW INSTRUMENTATION PRODUCTS
FEB10 Batch Controller
REMOTE or INTEGRAL METER
MOUNTING
Provides automatic batch control with one
or two stage outputs. Display provides
batch quantity as well as status at each
stage of the batch process. Batch limiting
& no flow detection plus automatic over
run compensation. Other features include
remote stop / start, system interlocks and
multiple batch controller networking.
ANCILLARY PRODUCTS
Cooling Fin
When fitted to flow meter, the
cooling fin allows meters to be
fitted with electronic display to
be rated to 120 deg C
Compact design allows
adequate heat dissipation in
ambient temperatures
ANCILLARY PRODUCTS
FI-420 Frequency Converter
The Frequency converter is a
programmable, non volatile PCB
which is link selected to serve as
either a frequency to current
converter (F/I) or a single point
flow rate alarm device for high or
low rate detection - Board fits
onto flow meter output PCB.
FI-420 Programmed at factory
or in situ with hand held
programmer
ANCILLARY PRODUCTS
RELAY OUTPUT BOARD
The relay output boards are an
option for the Z3 & B1
Instruments. The relays will switch
higher loads ( 5 Amp ) than the
solid state switches provided as
standard in these instruments
ANCILLARY PRODUCTS
PD2 Pulse Discriminator
Module
Application is for
discriminating bi-directional
flows. Accepts two
independent inputs from
flow meters with quad pulse
outputs. Discriminates flow
direction from inputs and
provides forward & reverse
pulse outputs for each flow
direction
ANCILLARY PRODUCTS
PR2 Pulse Repeater Module
The pulse repeater provides
electronic protection to the
flow meter output in
situations where associated
external circuitry may have
heavy electronic loadings,
non regulated power
supplies or electrical surges
or spikes
ANCILLARY PRODUCTS
Flow Instrumentation Products
Exd Explosion Proof Housing
Robust aluminium or stainless field
mount housing.
Four Large external non- invasive
operational switches.
IP66 ~ Nema 4X Rated.
View, program & operate instruments
without cover removal.
Certifications – FM, ATEX, SAA
ANCILLARY PRODUCTS
Flow Instrumentation Products
Mechanical Registers
Standard - without accuracy adjustment
M1 Register
M3 Register
As an alternative to electronic
totalisers, robust mechanical registers
with metal housings offer 3 or 4 large
resettable digits & 6 or 8 accumulative
total displays clearly visible for
loading & un-loading sites at
petroleum depots, mining,
construction & marine facilities
ANCILLARY PRODUCTS
Flow Instrumentation Products
V1 Register with accuracy
adjuster
Mechanical Registers
V Style - with accuracy adjustment
As an alternative to electronic totalisers,
robust mechanical registers with metal
housings offer 5 large re settable digits
& 8 digit accumulative total displays
clearly visible for loading & unloading sites at petroleum depots,
mining, construction & marine
facilities
ANCILLARY PRODUCTS
Flow Instrumentation Products
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Ticket Printers
Meter Register and Ticket
Printer combine together to
produce clean, detailed
printed records of high
speed fluid deliveries and
transactions
ANCILLARY PRODUCTS
Flow Instrumentation Products
Mechanical Preset Batch Registers
As an alternative to electronic
batch controllers or in Ex Proof
applications, mechanical preset
registers with shutoff valve are
available in sizes from 2” to 4”
ANCILLARY PRODUCTS
Typical Y Strainer
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STRAINERS
As the meters are only
suitable for clean
liquids it is important
that any impurities are
removed prior to the
meter.
Recommended Mesh Sizes
Mesh Size
SIZE
Micron
Size
1/4"
200 mesh
75
DN8
3/8"
200 mesh
75
DN10
1/2"
100 mesh
150
DN15
1"
50 mesh
250
DN25
1 1/2"
50 mesh
250
DN40
2"
25 mesh
500
DN50
3"
25 mesh
25 mesh
500
500
DN80
DN100
4"
HIGH PRESSURE METERS
HIGH PRESSURE MODELS
High Pressure Models
Sizes up to 50mm
Pressures to 400 Bar (6000 PSI )
Special end connections available
Hall effect output
Deep Sea applications
Chemical Injection
Hydraulic applications
FLOWMETER CALIBRATION
Every Flowmeter undergoes a
check before leaving the
factory for correct operation &
function of pulse outputs &
ancillary electronics if fitted.
Meters are then compared
against a master meter which is
traceable to the Australian
National Standards & issued
with a calibration report.
METER CALIBRATION
Company has 4 meter
calibration test benches using
certified master meters for
validating meter accuracy.
Small meters to 750 l/hr.
Medium meters to 500 l/min.
Large meters to 1500 l/min.
POSITIVE DISPLACEMENT METERS
Installation Points:
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PD Meters do not work well with silty or dirty fluids
( Use Strainers before meter )
Straight Pipe not necessary before meter.
Teflon Tape can cause rotor stoppages.
High Velocity flows can cause rotor destruction (
Slowly ramp up flow on start up )
Avoid Water Hammer caused by closing valves
quickly in batch applications
Flush Pipe Lines prior to meter installation
RECOMMENDED INSTALLATION
TROUBLE SHOOTING
Symptom
Meter
Possible cause
1. Output signal
interference
Solution
1. Ground shield of signal cable
2. Re-route cable from high electrical energy sources
2. Entrained air or
gas
1. Rem ove source of air or gas entrapm ent
3. Pulsating flow
from
1. Increase back pressure on pum p
isolation
valve
Flow meter
isolation
valve
2. Install an upstream air elim inator
readings
are high
reciprocating
style pum p
2. Install a fast response one w ay check valve
strainer
3. Install a surge arrestor betw een pum p & m eter
4. Re-calibrate m eter in situ to com pensate for pulsations
5. Change pum p style to sm ooth delivery type pum p
1.
Meter
readings
are low
Dam aged or
w orn rotors
2. Dam aged or
w orn
m easuring
cham ber
3. Output signal
interference
1. Inspect, repair, clean or replace rotors
1. Inspect m easuring cham ber for dam age - repair
2. Check concentricity of rotor shafts w ithin cham ber
1. Ground shield of signal cable
2. Re-route cable from high electrical energy sources
3. Check all electrical term inations & w ires for continuity.
1. Rotors fouled
1. Check that rounded teeth are tow ards base of cham ber
2. Check for obstruction due to foreign particles
3. Clean, repair or replace rotors
2.
No output
from
m eter
Meter
incorrectly
reassem bled
3. No output from
output board
1. See instructions for reassem bly of m eter w ith
particular em phisis on positioning of rotors & m agnets
1. Check term inal connections & solder joints
2. Ensure dc voltage is available at Vdc & 0v and
receiving instrum ent is fitted w ith a pull up resistor
3. Replace output board
Not
reading
on
readout
1.
Faulty
receiving
instrum ent
1. Check DIP sw itch settings & program data
2. Check term inal connections & electrical continuity
3. Repair / replace receiving instrum ent
by-pass
valve
Open downstream
valve last
It is important when
starting up the process
that the downstream
valve is slowly opened
last
ADDITIONAL PRODUCTS
Specialised Fuel Meters
Additional Products
Low cost fuel flow meters designed
for monitoring of fuel in Trucks,
Buses & vehicles
EM025 Meter
EM008 Meter
METER APPLICATIONS
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Acids
Alcohol
Water
Fuel Oils
Diesel
Liquid Propane
Bitumen / Asphalt
Tallow
Paint
Pharmaceuticals
METER APPLICATIONS
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Pesticides Solvents
Chemicals
Foods
Beverages
Vegetable Oils
Inks
Adhesives
Hydraulic Oil
Resins
METER APPLICATIONS
INDUSTRY
Aviation
Beverages
Cement / Ceramic / Glass
Chemical
Construction
Cosmetics
Energy
Food Industry
Gas & Oil
Lubrication
Marine
USAGE
Fuel Management, water & chemical loading / unloading
Alcoholic Spirts , Fruit Juices - Milk
Additives , Water
Ammonia, Caustic Soda, Methyl Chloride, Butane, Acetones
Fuel, Oils
Perfume, Foundation Creams, Alcohol, Shampoo, soaps
Fuel, Water, Freon, LPG.
Sauces, Pastes, Glucose, Chocolate, Yeast, Mayonaise.
Mecapatans, LPG, Additives, Oils
Oils, Coolants, Hydraulic fluids
Fuel monitoring, Loading / Unloading
METER APPLICATIONS
INDUSTRY
USAGE
Metal Manufacturing
Oils & Fats
Release Agents, Acids, Water, Oils
Vegetable Oils, Cooking Oils, Lards, Tallow.
Paints / Ink
Paints, Solvents, Printing Inks
Petrochemical
Petroleum
Pharmaceuticals
Ethylene Oxide, Propylene, Vinyl Chloride, Monomers.
Heavy Oil, Gasoline, Bitumen, Kerosene, Napthia.
Alcohol, Water, Syrups, Glycerine, Liquid Sugar
Pulp & Paper
Dyes, Acids, Additives.
Semi- Conductor
Acids, Solvents, Chemicals.
Textiles
Dyes, Bleaches, Chemicals.
Toiletries
Shampoo, Conditioner, Alcohol, Gels.
Transport
Fuel Monitoring, Tanker Loading / Unloading
Water treatment
Fluoride, Acid Addition, Chemicals, Flocculants.