JSG Industrial Systems

14 Types of Flow Meters

Industrial Flow Meters

Flow meters are devices used to measure the flow rate or quantity of a gas or liquid moving through a pipe. The choice of flow meter depends on factors such as the fluid characteristics, the environment in which it operates, the accuracy required, and the budget. Here’s a comprehensive list of flow meter types:

Different Types of Flow Meters their Uses and Benefits

1. Differential Pressure Flow Meters

Differential Pressure (DP) Flow Meters are among the oldest and most common methods for measuring fluid flow in pipes. The basic principle involves measuring the pressure drop across a constriction (or primary element) placed in the flow path. As fluid passes through this constriction, it accelerates, causing a drop in pressure between the upstream side and the downstream side of the constriction. This pressure drop is proportional to the square of the flow rate, allowing the calculation of the flow rate based on the measured differential pressure.

Industrial Uses

DP Flow Meters are used across a vast range of industries due to their versatility and reliability. Some common applications include:

  • Water and Wastewater Management: For measuring water flow in treatment plants and distribution systems.
  • Oil and Gas Industry: For measuring the flow of hydrocarbons in pipelines and refining processes.
  • Chemical Manufacturing: For controlling and monitoring the flow of various chemicals and reactants.
  • Power Generation: For steam flow measurement in boilers and for cooling water in turbines.
  • Food and Beverage: For managing the flow of liquids in processing and filtration systems.


  • Versatility: Suitable for a wide range of fluids, including liquids, gases, and steam, across various temperatures and pressures.
  • Reliability and Durability: With no moving parts in the primary element, DP meters offer high reliability and long service life.
  • Accuracy: When properly calibrated and installed, they can provide accurate flow measurements suitable for many industrial applications.
  • Established Technology: The principles and practices around DP flow meters are well-understood, with standardized calculations for different primary elements.
  • Cost-Effectiveness: Especially for large pipe diameters, where other types of flow meters can be prohibitively expensive to install and maintain.

2. Velocity Flow Meters

Velocity flow meters directly measure the velocity of a fluid moving through a pipe and use this information to calculate the flow rate. The flow rate can be determined by multiplying the fluid’s velocity by the cross-sectional area of the pipe. These meters are versatile and can be used with a wide range of fluid types, including liquids, gases, and steam. There are several types of velocity flow meters, each employing different methods to measure the flow velocity.

Industrial Uses

Velocity flow meters are utilized in various industries for numerous applications, including:

  • Water Treatment and Distribution: For measuring the flow of water in treatment plants and distribution systems.
  • Chemical and Pharmaceutical Industries: To monitor and control the flow of chemicals, solutions, and other fluids in manufacturing processes.
  • Oil and Gas Sector: For the measurement of hydrocarbon flow in pipelines and processing facilities.
  • Food and Beverage Production: To ensure accurate flow rates of liquids in processing plants, including water, oils, and other ingredients.
  • Energy and Power Generation: For measuring the flow of steam, cooling water, and other fluids associated with power generation.


  • Versatility: Can be used with a wide range of fluid types and in various pipe sizes.
  • No Obstruction to Flow: Many velocity flow meters (e.g., ultrasonic, magnetic) do not intrude into the flow stream, minimizing pressure drop and the risk of clogging.
  • Accuracy: Offer high accuracy, especially in clean, well-conditioned flows.
  • Digital Outputs and Connectivity: Many modern velocity meters come with digital outputs and connectivity options for easy integration into control systems.
  • Low Maintenance: Non-intrusive designs like magnetic and ultrasonic flow meters require less maintenance.

Need Assistance?

We're here to assist you in identifying the solution that best aligns with your needs.

3. Positive Displacement Flow Meters

Positive Displacement (PD) Flow Meters measure the flow rate of a fluid by capturing a fixed volume of fluid and counting the number of times this volume is filled and discharged. Unlike other types of flow meters that infer flow rate through indirect means (such as velocity or pressure differential), PD meters directly measure the flow by dividing the fluid flow into discrete parts. This method provides a highly accurate flow measurement, making PD meters especially useful for billing and precise quantitative control applications.

Industrial Uses

Positive Displacement Flow Meters are widely used across various industries for applications requiring high accuracy and precision:

  • Water Billing: Particularly in residential and commercial applications for accurately measuring water consumption.
  • Chemical Dosing: In the chemical industry, for precise measurement and control of the dosing of chemicals into processes.
  • Food and Beverage: For accurate dispensing and measurement of ingredients and during bottling operations.
  • Pharmaceuticals: In the manufacturing of pharmaceuticals, where precise quantities of liquids must be measured and controlled.
  • Oil and Gas: For the measurement of hydrocarbons, especially in custody transfer and billing applications where accuracy is paramount.
  • Paints and Coatings: For measuring and dispensing exact amounts of paints, dyes, and coatings.


  • High Accuracy and Precision: PD meters are extremely accurate, making them suitable for applications where precise measurement is critical.
  • Low Flow Capability: They can accurately measure very low flow rates, which is difficult for other types of flow meters.
  • Viscosity Independence: Their measurement accuracy is not significantly affected by fluid viscosity, making them ideal for a wide range of liquid types.
  • Direct Measurement: By measuring volume directly, they provide a true measure of fluid flow without needing conversion.
  • Minimal Need for Straight Pipe Runs: PD meters are less sensitive to flow profile disturbances, allowing for more flexible installation options.

4. Mass Flow Meters

Mass flow meters directly measure the mass flow rate of a fluid traveling through a device, unlike other types of flow meters that measure the volume of the fluid and require separate calculations to determine the mass flow. This direct measurement is crucial in applications where the mass of fluid, rather than its volume, is required for the process control or measurement accuracy. The two most common types of mass flow meters are Thermal Mass Flow Meters and Coriolis Flow Meters, each operating on different principles.

Industrial Uses

Mass flow meters are essential in various sectors, including:

  • Chemical and Pharmaceutical Industries: For precise control of ingredient addition in batch and continuous processes, ensuring product quality and consistency.
  • Oil and Gas: In upstream production for injection processes, midstream for custody transfer, and downstream operations for blending and refining processes.
  • Food and Beverage: For accurate dosing and blending of ingredients, ensuring consistency in recipes and product quality.
  • Semiconductor Manufacturing: Where precise control of gases and chemicals is critical for process consistency and yield.
  • Environmental Monitoring: For measuring emissions and compliance with environmental regulations.


  • Direct Measurement: Directly measures mass flow, which is not affected by changes in temperature or pressure, unlike volumetric flow measurements.
  • Accuracy and Precision: Provides high accuracy and precision, crucial for process control and optimization in industries where material balances are important.
  • No Moving Parts (Coriolis): Coriolis meters have no moving parts, leading to lower maintenance and longer service life.
  • Versatility: Can measure a wide range of fluids, including gases, liquids, and slurries.
  • Multi-Parameter Measurement: Many mass flow meters can measure additional parameters, such as density, temperature, and viscosity, providing more data for process control.


5. Open Channel Flow Meters

Open Channel Flow Meters are devices designed to measure the flow of liquids in open channels where the liquid flows under the influence of gravity. Unlike in closed conduits, the fluid in open channels has a free surface exposed to atmospheric pressure. These flow meters typically measure the height (or head) of the liquid in the channel and use that information, along with the channel’s geometry, to calculate the flow rate. The most common types of open channel flow meters are weirs and flumes.

Industrial Uses

Open channel flow meters are used in various settings, including:

  • Water and Wastewater Treatment Plants: For measuring the flow of water and wastewater into and out of treatment facilities.
  • Irrigation Channels and Ditches: To monitor water distribution for agricultural purposes, ensuring fair and efficient use of water resources.
  • Stormwater Management: To measure runoff in open channels and culverts, aiding in flood prediction and water resource management.
  • Environmental Monitoring: For studying natural streams and rivers, tracking water usage, and monitoring effluent discharges.
  • Mining and Construction: For managing water used in these operations, including measuring flow in tailings.


  • Simplicity and Reliability: Open channel flow meters, especially weirs and flumes, have simple designs with no moving parts, leading to high reliability and low maintenance requirements.
  • Accuracy: When properly installed and maintained, they can offer good accuracy for measuring flow rates in open channels.
  • Versatility: Suitable for a wide range of flow conditions and water quality, including flows with sediment and debris.
  • Cost-Effectiveness: Installation and operation costs can be lower compared to other flow measurement methods, especially for large channel sizes.


6. Magnetic Flow Meters (Magmeters)

Magnetic flow meters, also known as magmeters, utilize Faraday’s Law of Electromagnetic Induction to measure the flow rate of liquid in a pipe. According to Faraday’s Law, when a conductive fluid flows through a magnetic field, an electric voltage is generated. This voltage is directly proportional to the velocity of the fluid moving through the field. By measuring this voltage, the flow rate of the fluid can be determined. Magmeters consist of a non-conductive pipe section with electrodes placed on opposite sides and coils to generate a magnetic field across the fluid.

Industrial Uses

Magnetic flow meters have a wide range of applications across various industries due to their versatility and reliability:

  • Water and Wastewater Treatment: For measuring the flow of water, wastewater, and treatment chemicals throughout the treatment process.
  • Chemical Processing: Used for dosing, chemical injection, and in processes where corrosive or abrasive liquids are present.
  • Food and Beverage: Suitable for sanitary applications, including the measurement of food slurries, beverage production, and cleaning processes.
  • Pharmaceuticals: In applications requiring high cleanliness and accurate flow measurement of liquids.
  • Mining and Mineral Processing: For slurry flow measurement and processing of minerals.
  • Pulp and Paper Industry: For measuring caustic and acidic fluids used in the paper manufacturing process.
  • Agriculture: For irrigation and distribution of water.


  • Accuracy: Provides high accuracy and repeatability for a wide range of flow rates and fluid conductivities.
  • Versatility: Can measure almost any liquid that is conductive, including aggressive and abrasive fluids.
  • Low Maintenance: With no moving parts and an obstruction-free design, magmeters require less maintenance than mechanical flow meters.
  • Suitable for Dirty Fluids: Effective in applications where the fluid contains solids or particulates, such as slurries and wastewater.
  • Easy Installation: Can be easily installed in existing pipelines without the need for extensive modifications.


7. Vortex Flow Meters

Vortex flow meters operate on the principle of vortex shedding, where an obstruction (a bluff body) in the flow path causes alternating vortices to form on either side of the obstruction. The frequency of these shed vortices is directly proportional to the velocity of the fluid, and thus, the flow rate can be calculated. This phenomenon is known as the Von Kármán Vortex Street. By counting these vortices over a period of time, the vortex flow meter provides a measurement of the flow rate.

Industrial Uses

Vortex flow meters have a broad range of applications due to their versatility and robustness:

  • Chemical Processing: For measuring the flow of chemical feedstocks, solvents, and process gases.
  • Oil and Gas Industry: Used for the measurement of hydrocarbon liquids and gases, as well as steam for enhanced oil recovery processes.
  • Utilities and Energy: For steam flow measurement in power plants and district heating systems, as well as for measuring natural gas for boilers and burners.
  • Water and Wastewater: For measuring flow in treatment facilities and large pipeline distributions.
  • Food and Beverage: Suitable for steam and hot water applications, as well as for flow measurement in process lines.
  • Pharmaceuticals: For measuring purified water, solvents, and other process fluids.


  • Accuracy and Reliability: Offers good accuracy for measuring the flow of gases, liquids, and steam under varying conditions.
  • Low Maintenance: The absence of moving parts reduces wear and tear, resulting in lower maintenance costs.
  • Wide Operating Range: Effective across a broad range of flow rates and temperatures.
  • Easy Installation and Use: Can be easily integrated into existing systems with minimal disruption.


8. Ultrasonic Flow Meters

Ultrasonic flow meters measure the velocity of a fluid through a pipe using ultrasound to determine the flow rate. They can be either clamp-on (non-intrusive) or inline (intrusive), with the former being mounted on the outside of the pipe and the latter installed within the flow stream. These meters utilize one of two primary principles: Doppler shift or transit-time difference.

Industrial Uses

Ultrasonic flow meters are versatile, finding applications in various industries due to their non-intrusive nature and wide range of measurable fluids:

  • Water and Wastewater Treatment: For flow measurement in water distribution networks, wastewater collection systems, and treatment plants.
  • Oil and Gas: Used for hydrocarbon flow measurements in upstream, midstream, and downstream applications, including custody transfer and leak detection.
  • Chemical and Petrochemical Industries: For managing and controlling the flow of various chemicals and process fluids.
  • Power Generation: For measuring the flow of cooling water, steam, and feedwater in power plants.
  • Food and Beverage: Suitable for sanitary applications where contact with the product is to be avoided.
  • Pharmaceutical Manufacturing: For measuring purified water, process fluids, and other critical fluid flows.


  • Non-Intrusive Measurement: Clamp-on models do not require pipe modification or process interruption for installation, reducing downtime.
  • Wide Fluid Compatibility: Capable of measuring clean, dirty, viscous, and particulate-laden fluids.
  • No Pressure Drop: Since there are no moving parts or obstructions in the flow path, ultrasonic meters do not introduce a pressure drop.
  • High Accuracy and Repeatability: Especially transit-time meters, which are highly accurate under stable flow conditions.
  • Versatile and Flexible: Can be used for temporary measurements or permanent installations across a wide range of pipe sizes and materials.
  • Maintenance-Free Operation: The lack of moving parts and external mounting (for clamp-on types) minimizes maintenance needs.


9. Thermal Flow Meters

Thermal flow meters measure the flow rate of a fluid (gas or liquid) in a pipe or duct by monitoring the heat carried by the fluid as it moves past a heated element or sensor. There are two main types of thermal flow meter technologies: Constant Temperature Anemometers (CTA) and Constant Power Anemometers (CPA). CTA maintains a constant temperature difference between two sensors, while CPA maintains a constant power input to the heater. The flow rate is determined based on the amount of heat absorbed by the fluid, which is proportional to its mass flow rate.

Industrial Uses

Thermal flow meters find applications across various sectors due to their unique measurement capabilities:

  • Environmental Monitoring: For measuring emissions, including greenhouse gases and pollutants in stack gases.
  • Chemical and Petrochemical Industries: For controlling and monitoring gas flows in processes, including inert, reactive, and corrosive gases.
  • HVAC and Energy Management: For air flow measurement in ducts to optimize heating, ventilation, and air conditioning systems.
  • Semiconductor Manufacturing: For controlling the flow of specialty gases in fabrication processes.
  • Pharmaceuticals: For measuring and controlling gases in production and packaging processes.
  • Biotechnology: For monitoring fermentation gases and other process flows.


  • Accuracy and Repeatability: Provides precise and repeatable measurements, crucial for process control and monitoring.
  • Low Maintenance: The absence of moving parts means less mechanical wear and lower maintenance costs.
  • Versatility: Can measure a wide range of gases, including corrosive and toxic gases, without requiring fluid properties calibration.
  • Ease of Installation and Use: Compact and easy to install in various orientations and locations, including tight spaces.
  • Minimal Pressure Drop: Since they typically do not intrude significantly into the flow path, they introduce minimal pressure drop.


10. Turbine Flow Meters

Turbine flow meters measure the flow rate of a fluid (liquid or gas) through a pipe by utilizing a turbine or rotor placed in the flow stream. As the fluid flows through the meter, it impinges on the turbine blades, causing the turbine to rotate. The speed of this rotation is proportional to the velocity of the fluid, and consequently, the flow rate can be calculated. The rotational speed is often detected by magnetic pickups, optical sensors, or other means to produce an electrical signal proportional to the flow rate.

Industrial Uses

Turbine flow meters are versatile and find applications across a variety of industries due to their accuracy and reliability:

  • Oil and Gas: Widely used for hydrocarbon liquid and gas measurement in production, refining, and distribution, including custody transfer applications.
  • Chemical and Petrochemical: For precise measurement of process fluids, facilitating process control and inventory management.
  • Water and Wastewater: For measuring water flow in treatment plants and distribution systems, as well as irrigation systems.
  • Food and Beverage: For monitoring the flow of ingredients, water, and other process liquids, ensuring consistent product quality and batch control.
  • Pharmaceuticals: Used in manufacturing processes where accurate dosing and flow control of liquids are critical.
  • Aerospace and Automotive: For testing and monitoring fuel flow rates.


  • Reliability: With proper installation and maintenance, turbine meters can provide years of reliable service.
  • Rangeability: Suitable for a wide range of flow rates, from very low to very high, without sacrificing accuracy.
  • Easy to Maintain: The design allows for easy cleaning and maintenance, which is particularly beneficial in applications with clean fluids.
  • Compatibility: Can be used with a wide variety of fluids, including liquids and gases, as long as they are clean and non-corrosive.


11. Gear Flow Meters

Gear flow meters, also known as positive displacement flow meters, utilize the mechanical action of rotating gears to measure the flow rate of a fluid. As fluid flows through the meter, it enters compartments formed between the gears and the metering chamber, causing the gears to rotate. Each rotation represents a fixed volume of fluid passing through the meter, allowing for highly accurate measurement of the total flow. The flow rate is determined by counting the number of rotations over a given period, typically with magnetic, optical, or mechanical sensors.

Industrial Uses

Due to their accuracy and versatility, gear flow meters are used in various industries, including:

  • Chemical and Petrochemical: For measuring the flow of chemicals, solvents, and other process fluids, where accurate dosing and flow control are critical.
  • Oil and Gas: In applications such as lubrication systems, hydraulic systems, and fuel metering, where precision in measuring viscous fluids is required.
  • Food and Beverage: For dosing and batching of ingredients, where hygiene and accuracy are paramount.
  • Pharmaceuticals: In manufacturing processes, especially for metering precise volumes of liquids in formulation and filling operations.
  • Paints and Coatings: For controlling the flow of viscous materials and ensuring accurate mixture ratios.
  • Automotive: In test stands and for metering fuel consumption and lubricants.


  • Accuracy: Offers excellent accuracy and repeatability, essential for process control and quality assurance in many industrial applications.
  • Versatility: Effective with a wide range of fluids, including those that are viscous, shear-sensitive, or contain particulates (as long as they do not impede gear movement).
  • Minimal Need for Straight Pipe Runs: Unlike many other flow meter types, gear flow meters require minimal upstream and downstream straight pipe, making them suitable for installations with limited space.
  • Durability: Robust construction and the ability to handle a wide range of operating temperatures and pressures.


12. Nutating Disk Flow Meters

Nutating disk flow meters fall into the category of positive displacement flow meters, which measure the flow rate of a liquid by dividing it into fixed, metered volumes. The key component of a nutating disk meter is a disk mounted on a central sphere located inside a spherical-sided chamber. As fluid flows through the meter’s chamber, it causes the disk to wobble or “nutate,” but not rotate fully. This nutation motion is converted into a rotary motion through the meter’s mechanism, typically driving a mechanical counter or an electronic output to indicate flow rate and total flow.

Industrial Uses

Nutating disk flow meters are used in various applications, including:

  • Water Treatment and Distribution: Commonly used for residential and commercial water metering due to their accuracy at low flow rates and affordability.
  • Fuel Dispensing: Including diesel, fuel oil, and gasoline dispensing applications, where precise measurement is crucial for commercial transactions.
  • Chemical Processing: For measuring the transfer of non-corrosive liquids in batch processes.
  • Food and Beverage: For metering edible oils, syrups, and other food-grade liquids in processing plants.
  • HVAC: In applications involving the measurement of heating and cooling fluids.


  • Accuracy: Offers good accuracy for certain applications, especially where flow rates are consistent and fluids are clean.
  • Durability and Reliability: With few moving parts and a simple mechanical design, nutating disk meters are robust and reliable over time.
  • Low Cost: They are among the more affordable types of flow meters, both in terms of initial purchase and maintenance costs.
  • Ease of Use and Maintenance: Their straightforward design makes them easy to install, use, and maintain.


13. Coriolis Flow Meters

Coriolis flow meters, based on the Coriolis effect, are recognized for their ability to directly measure both mass flow rate and density of fluids (liquids or gases) flowing through a tube. The Coriolis effect refers to the deflection of moving objects when they are viewed in a rotating frame of reference. In the context of these flow meters, the fluid passes through a vibrating tube; as the fluid’s mass flow changes, it causes a measurable distortion or phase shift in the vibration of the tube, proportional to the mass flow rate. This technology is highly accurate and provides a direct measurement without the need for compensation for temperature, pressure, or viscosity changes.

Industrial Uses

Due to their precision and versatility, Coriolis flow meters are used in various sectors:

  • Chemical Processing: For accurate dosing and measurement of reactants and products, critical in processes where material balances are essential.
  • Oil and Gas Industry: In upstream, midstream, and downstream applications, including custody transfer, where accuracy in measurement directly impacts revenue.
  • Food and Beverage: For managing ingredients in recipes, ensuring consistent product quality and compliance with industry standards.
  • Pharmaceutical Manufacturing: In formulations where precise measurement of components is critical for product efficacy.
  • Power Generation: For fuel measurement and handling, optimizing combustion processes and efficiency.


  • No Moving Parts: Results in minimal maintenance requirements and a longer operational lifespan.
  • Not Affected by Fluid Properties: Accurate across a wide range of temperatures, pressures, viscosities, and densities.
  • Efficiency and Accuracy: Enables significant cost savings through precise fluid measurement and reduced waste in process industries.
  • Robustness: Performs reliably in harsh environments and with aggressive or abrasive fluids.


14. Laminar Flow Meters

Laminar flow meters, also known as laminar flow elements (LFEs), are precision devices used to measure the flow rate of gases under laminar flow conditions. Laminar flow occurs when a fluid flows in parallel layers, with no disruption between the layers. This flow regime is characterized by smooth, orderly flow lines and occurs at low Reynolds numbers, typically below 2000. The principle behind laminar flow meters is based on the Hagen-Poiseuille law, which states that the volumetric flow rate through a pipe or duct is proportional to the pressure drop across the length of the pipe and inversely proportional to the fluid’s viscosity when the flow is laminar.

Industrial Uses

Laminar flow meters are used in applications requiring precise control and measurement of gas flow rates, such as:

  • Laboratories and Research: For experiments requiring precise control of gas flows, including calibration of other flow meters.
  • Semiconductor Manufacturing: In processes where accurate dosing of gases is critical for product quality and yield.
  • Pharmaceutical Production: For controlled environments where gas flow needs to be measured accurately for production and packaging processes.
  • Aerospace and Automotive Testing: In engine testing and research, where accurate measurement of air and other gases is essential.
  • Environmental Monitoring: For measuring emissions and air sampling to ensure compliance with regulations.


  • Accuracy: Provides highly accurate measurements, especially for low flow rates where other types of flow meters may struggle.
  • Repeatability: Delivers consistent measurements, which is crucial for process control and quality assurance.
  • Stability: Less prone to fluctuations and disturbances in the flow, leading to stable and reliable readings.
  • Minimal Influence from Fluid Properties: The measurement is less affected by the viscosity of the gas, provided the flow remains laminar.

Are you looking for ways to improve productivity, machine uptime, maintenance costs, and increase oil service life?

Submit the form and we will be in contact soon.

Lubrication Systems

Lubrication is critical in machine reliability. We have solutions to help you reach optimum machine reliability, efficiency and safety.

Fire Suppression

Fire poses a significant risk in industrial settings. We offer a range of fire suppression systems to suit your needs.

& Instrumentation

Instrumentation enables better management & control of processes. We offer a range of solutions  to measure and transfer fluids accurately with minimum downtime.