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FLOWMETERS
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GNW supply, repair and calibrate all aspects of Flowmeters and flow measurement equipment, providing a high standard of reliability and accuracy in the measurement of liquid and gas Whatever your requirements GNW will be able to provide a solution. From supplying low cost flow accessories to maintaining On-site large numbers of flowmeters. |
All our flowmeters have a long and reliable service life due to the careful selection of both materials and design.
All instrumentation undertakes rigorous tests and is monitored by our Q.A. Department from goods inwards through to despatch, ensuring that the customer receive the exact service they require.
GNW’s expertise in both electronics and fluid measurement ensures that all instrumentation is returned to the customer in excellent working order and is ready to be installed straight away.
Test Certificates or Certificates of Conformity can be supplied is required.
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Our Services Include:- |
Selection of the correct
type of flowmeter presents a challenge to the engineer because of the wide range
of flowmeters and equipment available today.
Factors to be considered in selecting
a flowmeter are:
Reliability
Maintenance requirements
Type of readout
Rangeability
Cleanliness of fluid or entrained solids
Cost
Accuracy
Viscosity and density of fluid
Corrosiveness of fluid
Extremes of pressure
and temperature
External environmental requirements due to corrosive or hazardous
atmosphere.
GNW’s range of Flowmeters include:-
VARIABLE ARE FLOWMTERS
The most economic of GNW’s range of flowmeters, designed for small fluid flows (gas or liquids). They can be widely employed where the fluid is free of entrained solids and where the system provides locations for good visibility and proper mounting.
| Applications to
winch variable area flowmeters are particularly suited are: Extremely low flows Wide turn down flows requiring linearity and 10:1 rangeability. Metering viscous fluids or fluids requiring steam jacketing Metering high accuracy. Where simple low cost approach to direct reading local indication is required, a non-transmitting glass tube flowmeter is recommended for such use. |
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DIFFERENTIAL PRESSURE METER
One of the most widely used meters in industrial process control. Important advantages are is simplicity, reliability and relative low cost.
| Three outstanding features of this type of meter are:- It
does not require actual flow calibration |
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MAGNETIC FLOWMETERS
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These approache the ideal flowmeter since it offers no restriction in the flowline and can handle fluids that most other types of flowmeter can not take. Applications
for magnetic flowmeters are: |
Magnetic flowmeters are ideal
in plants where pressure drop losses must be kept to a minimum.
They can also
handle a wide range of corrosive fluids.
OPEN CHANNEL FLOW MEASURING DEVICES
Commonly used when measuring flow in open channels, tanks or ditches. Open channel flowmeters restrict the flow stream causing the upstream level to increase of decrease as a function of flow.
SINGLE JET FLOWMETERS
GNW offer a range of single jet flowmeters for cold and warm water with dry and super dry registers depending on the customer requirements.
| The single jet meter employs the inferential principle of design which uses the velocity of flow converted to specific volume through the meters register gearing. A rotor is incorporated within the meter casing specifically designed to measure the exact flow. Due the principal of operation theses meters are manufactured with tolerances which allow for installation in many varying applications. All types can be offered with pulse output devices for remote reading, billing or water management systems. |  |
VORTEX FLOWMETERS
A general purpose broad application instrument. It has no moving parts and offers welded corrosion-proof construction, internal sensing, modular electronics and weather tight housing.
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Applications
for the Vortex Flowmeter include: * Petroleum * Chemical food * Pulp and paper * Metals and mining * Power * Water and waste treatment industries |
VERTICAL, HORIZONTAL & HELICAL VANE ROTOR METERS
| These flowmeters are manufactured for the purpose of monitoring large flows of water for water system management and Commercial billing purposes. Vertical,
Horizontal and Helical Vane Rotor Meters with pulse outputs for operation with
various auxiliary equipment are available. |
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COMBINATION FLOWMETERS
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Specifically
designed where wide variation in flow can be expected, such as hospitals, schools,
offices and other places where both very low and very high flows can occur. These wide flow ranges are measured by using built in changeover valves. The low flows are measured by a small by pass meter. When the flow increases the valve opens so that the main bulk meter comes into operation for the larger flowrates. |
Semi positive displacement flowmeters operate on the volumetric principle that for each revolution of the piston a fixed amount of water is measured.
The design of the working chamber and piston ensure that the accuracy of the meter is maintained over long periods.
SPECIALITY FLOWMETERS
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range of Volumetric Flowmeters for the measurement of oil are available from GNW.
These flowmeters range from very low to medium flows passing oil of varying viscosities.
They can be fitted with pulse outputs enabling the meters to interface for batching
operations or remote reading. Portable Helical Vane Meters for use with standpipes /hydrants are available in aluminium for ease in installation. Irrigation meters designed for rugged applications with sustained high flows are also available. |
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Batching Meters provide the close control needed to maintain precise dosing for hot & cold water systems. When supplied with pulsed outputs the meter can activate the opening and closing of valves
Multi Jet Flowmeters operate on the inferential principle with a multi-ported measuring element placed within a flow designed meter casing. This design jets the water onto the rotor through openings in the measuring chamber and allows exit only through controlled outlet ports.
ACCESSORIES
GNW
offer an extensive range of accessories to complement its range of flowmeters.
Including:-
* In line strainers
* Spool pieces
* Valves
* Fittings
* Test benches.
* Data logging systems
* Batch Controllers
* Totalisers
* Signal convertors