Flow Meters

In all industries, machines and equipment requires a specific flow rate to operate proficiently. Flow meters are instruments specifically designed to record a flow rate measurement of liquids, gases or vapour in a variety of ways to suit the industry and applications needs. Cromwell stock high performing flow meters from market leader Tuthill.

What are Flow meters?

A flow meter, also known as a flow sensor, flow indicator or flow gauge is an instrument designed to measure the speed or the amount of gas, liquid or vapour moving through a tube or pipe by measuring the non-linear, linear, mass or volumetric flow rates.

Why Flow meters?

By capturing the flow rate measurement, flow meters readings can be interrupted to help to improve accuracy, efficiency and precision that can ultimately results in positive, cost saving and time saving solutions.
Flow meters can be either a totalising flow meters that constantly measure the medium passing through it, or as a time measuring unit, which measures the flow rate over a set time period to help understand a variety of measurements.

When are flow meters used?

Different types of flow meters are used in a range of different ways depending on its application. Flow meters are used in all types of industries and in domestic settings, here are a few if the main industries:
• Water treatment plants
• Irrigation
• Industry washing systems
• Cooling systems
• Oil and gas
• Chemical
• Food and beverage
• Refining
• Domestic

Flow meter types

There are various flow meter types, each designed for a specific application or industry and available in both digital and analogue types.
The most well-known types of flow meters are:

• Thermal flow meters   -   Designed for mass flow measurement of temperature rise and rate of heat loss.
• Coriolis flow meters   -   Used for mass flow metering and excellent for repeatably accurate measurements.
• Ultrasonic flow meters   -   Measures the velocity of fluids flowing through a pipe.
• DP meters (differential pressure )    -   Predominantly found in the oil, gas, chemical, power and oil industries.
• Vortex meters   -   Used to measure liquid, gases and steam flow within the oil and gas, food and beverage, refining, chemical and petrochemical industries.
• Multiphase meters   -   Determine phase fractions using a combination of electrical impedance measurements and single high energy gamma, combined with venturi and cross correlation for velocity measurements.
• Magnetic meters   -   Used to measure the velocity of conductive liquids in pipes, such as acids, water, caustic and slurries.

Considerations when choosing a flow meter

• Flow type - The are different types of flow meters that are specifically designed to measure gas, liquid or vapour, consider this when making your selection.
• Flow rate range - the minimum and maximum range a flow meter can precisely measure.
• Compatible fluid

FAQs

How accurate are flowmeters?

Flowmeters operating ranges can be grouped into 3 categories, which are defined by an associated error percentage of the measured value or reading. The accuracy standard of flow measurement on devices is +/- 5.0 percent.

What is the difference between flow rate and flow?

The flow rate is the quantity of flow in volume or mass in a unit of time, whereas the flow is the total quantity in volume or mass that passed through a flow meter.