Installing a meter for an application where accuracy and repeatability are critical, it is necessary calibration is carried out regularly, and supplied with documentation of that calibration.

A meter that is not individually calibrated cannot be relied on as truly accurate to its specification.

Production tolerance differences can and will affect a meter’s accuracy. For this reason, meters must calibrated to ensure specified accuracy and functionality for the user.

Traceable Calibration Certification is available on request.

MAGNETIC FLOWMETERS

These approach the ideal flowmeter since they are low-maintenance, offer high accuracy and are insensitive to viscosity, pressure and temperature changes and offer no restriction in the flowline and can handle fluids that most other types of flowmeter can not take.

They are ideal in plants where pressure drop losses must be kept to a minimum.

They can also handle a wide range of corrosive fluids and heavy slurries.

Applications for magnetic flowmeters are:

Monitoring and control of a variety of industrial effluents
Paper pulp waste
Mining slurries
Brine
Liquid food products
Detergents
Waste sludge in sewage treatment plants and water and waste industries.
Corrosive acids
Solid bearing fluids
Electrolytes
Process chemical

Advantages for magnetic flow meters

Non obtrusive flow in full-bore models
No moving parts
Virtually no pressure drop
Insensitivity to viscosity, specific gravity, temperature and pressure (within certain limitations)
Will work with laminar, turbulent, and transitional flows
Can respond well to fast changing flows (for high-frequency DC pulse and AC excitation designs only)
Good accuracy (0.5 to 1%)Can handle slurries and heavy particulates
Lining protectors available for harsh, chemically corrosive, and abrasive fluids

Disadvantages for magnetic flow meters

Fluid must be conductive (typically > 5µS/cm)
Pipe must be grounded

OPEN CHANNEL FLOW MEASURING DEVICES

Designed for peak performance in multiple applications, including small and large pipes, high and low flow. Open Channel Flowmeters are commonly used when measuring flow in open channels, tanks or ditches (Included are tunnels, non-pressurised sewers, partially filled pipes, canals, streams, and rivers).

Open channel flowmeters restrict the flow stream causing the upstream level to increase of decrease as a function of flow.

We offer single-channel and dual-channel monitoring with wireless and standard telemetry for field versatility

Gauges North west offer a range of unique, totally non-invasive ultrasonic flow meters are suitable for use on clean and dirty liquids with varying pipe sizes. Enabling process contamination free measurement of liquids and gas flow.

Ideal for hygienic applications they do not present any potential bug traps and equally suitable for hazardous chemicals as there are no potential leak paths, as they are mounted completely external to the pipe wall.

There are two main types of ultrasonic flow meters, doppler flow meters and time transit ultrasonic flow meters.

A time transit ultrasonic flow meter requires a clean liquid without particulates or bubbles and can be used for both liquid and gas applications. It has better accuracy than that of a doppler flow meter and will typically offer accuracies of ±2% full scale. A doppler flow meter requires particulates or bubbles in the media. The minimum diameter size of the particulate is typically 30 microns and requires a minimum concentration levels of 25 ppm.

Typical Application for ultrasonic flow meters

Process contamination free measurement of flow
No leak potential
Allows for easy installation without disturbing existing pipe work
Suitable for aggressive chemicals as no contact with the media
Doppler flow meters are suitable for slurries

Batching flowmeters offer a lo-cost solution for accuratley controlling batched quantities of oils, fuels, solvents and high and varying viscosity liquids. They 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

A preset adjuster allows you to visually set the batch quantity cleared. The flow of water can then be controlled by the operator until the batch is successfully completed.

Batch Control Meters are capable of delivering large volumes quickly and accurately. Suitable for installation in vertical, horizontal or inclined pipework.

Advantages
Highly accurate measurement of flow
Low pressure drop
Keeps pumping costs down
Easy to install
No power supply needed

Suitable for:
filling,
fuelling,
batching and monitoring.

Can be used to meter oils, petrol, diesel and chemicals.

Turbine flowmeters are a precision measurement device that allow high accuracy with minimal cost and configuration. 

Gauges North West can offer a range of materials from low cost nylon and aluminium bodies to specialist options such as PVDF or stainless steel for more aggressive, higher temperature applications.

Remote flow rate indication, alarms, totalising and batch control functions are available enabling the flow meter to be located some considerable distance from the associated secondary instrument.Advantages for turbine flow meters

Disadvantages for turbine flow meters

Typical Application for turbine flow meters

Variable Area Flowmeters (alos known as Rotameters) offer cost effective yet accurate solutions for applications requiring visual indication of flow or flow rate.

Simple to Install and 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.

Available in a wide range of materials including low cost acrylic and specialist options such as PTFE for aggressive media or stainless steel for high temperature and pressure applications. We provide the option of a wide range of control and output options including control valves, set-point switches and analogue outputs.

Typical Application for variable area flow meters

Liquid flow meter or gas flow meter where high accuracy is not required
Measuring water and gas flow in plants or labs
Monitoring chemical lines
Purging instrument air lines (i.e. lines that use a valved meter)
Monitoring filtration loading
Monitoring flow in material-blending applications (i.e. lines that use a valved meter)
Monitor makeup water for food & beverage plants

Key Points for variable area flow meters

Variable area flow meters operate on the principle that the flow of the media will alter the position of a float in a tapered tube. The position of the float in the tapered tube is proportional to the volumetric flow rate
Typical accuracy of variable area flow meters is ±3% full scale
A variable area flow meter normally has a turn down ratio in the region of 10:1
A variable area flow meter normally requires vertical installation and a straight pipe run (minimum length of five times the diameter of the pipe) before the flow meters inlet

Advantages for variable area flow meters

Low cost
Simple to install
Easy to use and virtually maintenance free
Wide choice of materials including all PTFE for aggressive fluids
Many control options including control valves, set-point switches and analogue outputs

Disadvantages for variable area flow meters

Lower accuracy compared to many other flow meter technologies
Affected by pulsation
Sensitive to fluid changes such as viscosity, density and temperature

Vortex Flowmeters,are a general purpose broad application instrument. Suitable for aggressive environments as they have no moving parts and offer welded corrosion-proof construction, internal sensing, modular electronics and weather tight housing, enabling them to be used on non-viscous, clean or dirty water-like liquids

They are ideal for measuring process water, water-based machine coolant, or water/glycol coolants as they can alert process operators of dangerous flow deviations.

Coriolis Mass Flowmeters are specially designed and manufactured to meet the demands of difficult applications. These flowmeters are available for measuring mass flow and density of liquids, slurries and gases.

They use the Coriolis force for direct massflow measurement of any fluid.
Since mass is measured directly, no calculations involving density or volume are required. Measurements are thus immune to variations in pressure, temperature, density, viscosity, electrical conductivity or the presence of gas bubbles or solid particles in the fluid medium.

The Coriolis technology is ideal for demanding fluid measurement applications – independent of whether the fluid is conductive, multi-phase or viscous. The measuring pipe is self-draining. The device’s self-diagnostic and digital signal processing functions ensure high long-term stability and reliability.

Gauges North West Ltd 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