07/27/2020 | Industrial Water Treatment | 8 MINUTE READ

Exploring the Different Types and Applications Water Flow Meters

When you need to measure the flow of water in a plant or industrial facility, you can do so by using a water flow meter. A water flow meter is a type of instrument that’s used to accurately measure the amount of water that is flowing through a pipe, which allows you to ascertain the current flow rate. Different pieces of equipment require different flow rates, which is why it’s important to use a water flow meter. There are a variety of different types of water flow meters that you can select from, which differ based on such factors as cost, measurement applications, and overall maintenance requirements.

Water flow meters are capable of measuring hot and cold water, dirty water, clean water, and slurries, which makes this type of tool versatile. The applications that water flow meters can be used for depend on the type of meter that you choose. While some meters are designed to measure the flow of lubrication oils, polymer additives, and printing ink, others are designed to work in pharmaceuticals and wastewater treatment facilities.

Whether you want to measure the flow rate of a municipal water supply or would like to make sure that the flow rate of fluids in a closed pipe isn’t too low, these water flow meters can give you precise readings that will allow you to maintain optimal flow rate and make immediate changes when necessary. Without this information, the pressure in a pipe could build to an unsustainable amount before you have any idea that the flow rate has worsened, which could lead to a burst pipe or any number of additional problems.

This article explores the various types of water flow meters and the many ways that you can use them.

Water Flow Meters Explained

A water flow meter is a kind of instrument that’s designed specifically to measure the flow rate of water in a pipe. There are many different types of water flow meters that you can obtain for your facility, each of which has its own benefits when used for certain applications. For many pipes and similar systems, the water must be kept at a regulated flow rate to make sure that the system is running efficiently.

At low flow rates, it’s possible that the water velocity would be low enough for suspended solids to settle towards the bottom of the pipe, which worsens the efficiency of the pipe and will eventually lead to a buildup of contaminants that could cause damage. Since water flow meters can be used for a wide range of applications, there are many reasons that these meters are needed. For one, knowing that the fluid is in the correct spot at the correct time can be highly beneficial towards making sure that operation costs and efficiency are maintained.

These meters could also be used to make sure that the fluid remains in motion or to determine if a tank is balanced properly. Any drops in flow rate could indicate that the quality of the water is worsening and needs to be treated. There are also a few applications where accurate flow measurements are essential for the quality of a product as well as the health and safety of the final product. These meters are relatively easy to install in pipes depending on the type of meter that you choose.

Water Flow Meter Types

There are four major types of water flow meters that can be installed into a pipe. It’s important to know the difference between these flow meters because the type you choose can dictate what kinds of benefits you receive. While most water flow meters can be used across all applications, some meters are more effective than others for specific applications. Keep in mind that there are additional types of flow meters that you could select for your facility. However, the following meters represent the four primary options that are available for purchase.

Mechanical Flow Meters

Mechanical flow meters are easily the most common flow meters around, which is mainly due to these meters being more affordable than other types. A mechanical flow meter measures the flow of water via turbine rotation, which uses a basic propeller, paddle, or shunt design. The flow rate of the water equates to the speed of the blades. If you want to use a mechanical flow meter, they can become clogged in the event that the water is dirty or more contaminated than you anticipated. As such, you likely shouldn’t use this type of flow meter to measure the flow of a slurry solution. Because these meters can become clogged, maintenance is required more often than with other flow meters.

Vortex Flow Meters

Vortex flow meters are unique flow meters that measure the flow of water by using vortices. When a fluid pushes past an obstruction, swirls are produced that develop into a vortex. A sensor tab is equipped to the flow meter that flexes whenever vortices flow past it, which creates a frequency output that indicates what the flow rate of the water is. If you decide to select a multi-variable vortex flow meter, it can measure up to five different variables that might be useful for your specific application. These variables include mass flow, temperature, density, flow rate, and pressure. These meters work particularly well with large pipes.

Ultrasonic Flow Meters

Ultrasonic flow meters are designed to use ultrasound technology to measure the speed of the water as it passes through the pipe. There are two basic types of ultrasonic flow meters that you should be aware of, which include transit-time flow meters and clamp-on ultrasonic meters. If you choose a transit-time flow meter, a standard ultrasonic signal is sent downstream before another signal is sent upstream. These two signals are then compared to determine the flow rate of the water.

As for clamp-on ultrasonic flow meters, they can be placed on the outer portion of the pipe and are designed to shoot sound pulses through the walls of the pipe in order to receive a measurement. Since they can be installed on the outside of the pipe, they can be used for practically any application and work well with larger pipes.

Magnetic Flow Meter

Magnetic flow meters are able to measure the speed of water by using a simple magnetic field. When water passes through a magnetic field, it generates voltage. As such, a higher flow rate will invariably generate more voltage when sent through a magnetic flow meter. The electronic system that’s attached to this meter will receive a voltage signal, which is then converted into a volumetric flow rate. Keep in mind that there needs to be ions in the water in order for voltage to be generated, which means that a magnetic flow meter can’t be used with pure water that has no contaminants.

Water Flow Meter Measurement

When you use a water flow meter of any kind, you will be provided with a basic flow rate measurement. This measurement will be provided to you as cubic meters, which is displayed as m3 on the meter. While the display you use can be mechanical or electronic, the readings are the same. These readings will allow you to determine how many cubic meters of water are passing through the flow meter every second. When the liquid is flowing through a circular pipe, your calculations should take into account the radius of the pipe. If the flow meter is being positioned in a rectangular device or system, the width and height must be taken into account.

Your flow meter will give you the ability to determine if the current flow rate is ideal. If you’re provided with lower readings, this means that the flow rate of the water has decreased for some reason. It’s also possible that the flow meter needs to be repaired. What you do with the readings you receive depends on the application and the exact flow rate you wish to maintain. In the event that the flow rate is slower than you would like, water treatment may be necessary to get rid of some of the contaminants in the water.

Choosing the Water Flow Meter Right for You

When you’re trying to select the right water flow meter, there are many factors that you should take into account, which include:

  • The accuracy of the meter
  • How long the meter is designed to last
  • The requirements of operation
  • Maintenance requirements
  • Total costs
  • The flow rate range that the meter accommodates

With these factors in mind, you should be able to determine which flow meter is right for you. Since the four aforementioned flow meters are ideal for different applications, it shouldn’t be too difficult to select the right one. If accuracy in a flow meter is essential for your application, you’ll likely need to purchase a premium and more expensive water flow meter. The lifespan of the device also corresponds to the overall price. No matter which water flow meter you choose, being able to identify the flow rate of your water could keep serious issues at bay with the piping in your facility.

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Posted by Sensorex on July 27, 2020

Sensorex is a global leader in the design and manufacture of quality sensors for water quality and process applications. The company offers more than 2000 sensor packages for pH, ORP, conductivity, dissolved oxygen, free chlorine, chlorine dioxide, UV transmittance and other specialty measurements, as well as a full line of sensor accessories and transmitters. Its expert technical support engineers solve analytical sensor challenges with custom designs and off the shelf products.

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