Leading Hydraulic Flow Meter Manufacturers

Hydraulic flow meters measure the linear, nonlinear, mass, and volumetric flow rate of hydraulic fluids. The three parts of a hydraulic flow meter are the device, transducer, and transmitter. The transducer senses the movement of the hydraulic fluid, while the transmitter produces a flow signal from the transducer’s sensed signal. The calculation of the volume and flow is based on the concept that the passing fluid volume is proportional to the cross-sectional area and the fluid velocity. Read More…

Hydraulic Flow Meters Hydraulic flow meters measure the flow rate or volume of liquid inside a hydraulic system. Their general applications are testing, troubleshooting and maintaining hydraulic systems. Using hydraulic flow meters, operators of hydraulic systems can measure how efficiently and effectively their systems are running and properly address any problems into which they run.

Sierra manufacturers high performance mass flow meters and controllers for nearly any gas, liquid or steam. Customers choose Sierra when they need an accurate and repeatable flow measurement, short delivery lead times, expert flow advice and long term support. When it matters, choose Sierra. Visit www.sierrainstruments.com.

Sierra Instruments $$$

AW-Lake Company manufactures flow monitoring equipment and goes to market through four brands: TRICOR Coriolis Technology, LAKE Monitors, AW Gear Meters and Turbine Flow. The broad range of flow meters include coriolis mass, positive displacement, variable area and turbine technologies. We service many industries, including oil & gas, automotive, food & beverage, chemical processing and...

AW-Lake Company $$$

At Niagara Meters, we specialize in providing high-quality flow meters and comprehensive solutions to meet the diverse needs of industries worldwide. With our dedication to excellence and extensive experience, we have established ourselves as a trusted leader in the field of flow measurement. Our product portfolio encompasses a wide range of flow meters meticulously engineered to deliver accurate ...

Niagara Meters $$$

SIKA is a developer and manufacturer of flow control products and a wide variety of other measuring and monitoring systems. Our inventory includes flow sensors, flow meters, flow switches, and many more. We know that flow solutions aren't one-size-fits-all, which is why we provide consultation and flow management solutions that are individualized and customized to your requirements. When you...


Turbines is an ISO 9001:2000 certified manufacture specializing in the design of high quality, cost-efficient rugged turbine flow meters for industry oil and gas, and business flow measurement applications that require accuracy, repetition and reliability. We have established ourselves as a trusted leader in the field of flow measurement. We also offer a wide range of accessories such as...

Turbines, Inc. $$$
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Variable Orifice Hydraulic Flow Meter

What is Flow?

Measuring flow is essential to perfecting and improving the efficiency of a process and is a part of the dynamics and mechanics of fluids. It involves the movement of fluids subjected to unbalanced forces, which continue the motion of fluids as long as they remain unbalanced. Fluids measured by hydraulic flow meters are incompressible, meaning their density does not change when an external force is applied.

Flow is the measurement of the volume of a fluid as it passes a fixed point at an established unit of time. For hydraulic applications, flow is calculated in liters or gallons per minute. Fluid flow is the foundation of hydraulic systems and must be monitored carefully since hydraulic fluids transfer energy from one part of the system to another.

Functions of Hydraulic Fluids

Since not all hydraulic systems are the same, their fluids are chosen following the needs of an application. The properties of hydraulic fluids include viscosity, lubrication, demulsibility (the ability to release water), and chemical and environmental stability. Hydraulic fluids have five functions:

Power Generation

In a hydraulic system, the incompressible fluid transfers energy from one point to another to generate power. The pump initiates fluid flow, and pressure develops at the point of restriction.


One of the primary functions of hydraulic fluid is to remove contaminants, which can damage the system or reduce its productivity. The flow of hydraulic fluid removes any forms of foreign particles by moving them to the filtration system.


The constant movement of the various components of a hydraulic system creates friction that can cause wear and failure. The smooth flow of hydraulic fluids reduces friction by creating a lubricating film.

Sealing the System

Because all hydraulic systems operate under pressure, each system must have a tight seal. The proper hydraulic fluid forms an additional seal between mechanical parts.

Heat Transfer

The friction of hydraulic components produces heat that has to be cooled. The smooth and controlled flow of hydraulic fluids carries away any generated heat.

Types of Hydraulic Flow Meters

The selection of a hydraulic flow meter is a critical aspect of a system's function since an incorrect choice can lead to errors in diagnosis. The factors to be examined when making the selection are fluid properties, operating condition of the system, flow measurement, accuracy, effect of the flow meter on the fluid and vice versa, and cost. As with all flow meters, there are several types of hydraulic flow meters to choose from, with each type designed to perform with a certain type of hydraulic fluid.

Variable Orifice Flow Meter

A variable orifice hydraulic flow meter has a piston or ring connected to a spring. The force of the fluid displaces the piston or ring, which increases the size of the flow meter's orifice. The flow rate is indicated on an analog readout connected by a magnet to the piston or ring.

Variable Orifice Hydraulic Flow Meter

Gear Flow Meter

Gear type hydraulic flow meters are types of positive displacement flow meters that look like gear motors with intermeshed, rotating gears. The fluid flow rotates the gears, one of which is connected to the transducer. An increase or decrease in the fluid flow causes the gears to rotate faster or slower, providing the flow rate reading. More accurate gear type hydraulic flow meters have two transducers that measure direction and improve resolution.

Gear Hydraulic Flow Meter

Turbine Flow Meter

Turbine hydraulic flow meters are a very common type of mechanical flow meter. The turbine rotor is placed in a shaft between flow straighteners, and the flow of the hydraulic fluid turns the turbines. The transducer, connected to the turbine rotors, senses the movement of the blades, which is the flow rate.

Turbine Hydraulic Flow Meter

Choosing the Correct Hydraulic Flow Meter Manufacturer

To ensure the most constructive outcome when purchasing hydraulic flow meters from a hydraulic flow meter manufacturer, it is important to compare several companies using our directory of hydraulic flow meter manufacturers. Each hydraulic flow meter manufacturer has a business profile page highlighting their areas of experience and capabilities, along with a contact form to directly communicate with the manufacturer for more information or request a quote. Review each hydraulic flow meter company website using our patented website previewer to quickly learn what each business specializes in. Then, use our simple RFQ form to contact multiple hydraulic flow meter businesses with the same form.

Hydraulic Flow Meter Informational Video


Flow Meters Power Pages

Coriolis Flow Meters

Coriolis Flow Meters

A Coriolis flow meter measures mass by the inertia of a liquid or gas flowing through a vibrating tube that is equipped with a set of sensors at the inlets and outlets of the meter. The increased movement of the flow produces measurable oscillation that is proportional to the mass...

Flow Switches

Piston Type Flow Switch

A flow switch is a device that measures the flow rate and liquid pressure within a duct, loop, or system. Flow sensor and flow indication are other names for this switch. The primary purpose of a flow switch is to continually...

Level Switches

Level Switch

A level switch is an electrical or mechanical method for measuring the level of a liquid, powder, or granule material. It is designed to activate an alarm if the material level in a container passes a predetermined height or depth...

Magnetic Flow Meters

Magnetic Flow Meters

A magnetic flow meter is a volumetric flow meter that uses electrodes connected to the liquid flow to measure the velocity of fluids in a tube or pipe. The unique design of magnetic flow meters allows them to take their readings without the need for any moving parts...

Mass Flow Meters

Mass Flow Meters

A mass flow meter is a way of measuring the volume or mass of a gas or liquid passing through a system at a specific point in the flow system. They are used to measure linear, nonlinear, mass, and volumetric flow rates...

Ultrasonic Flow Meters

Ultrasonic Flow Meters

An ultrasonic flow meter measures the flow of a liquid or gas by sending ultrasonic waves across a pipe, containing the flow in the direction of the flow and in the opposite direction of the flow. The ultrasonic waves and the velocity of...

Types of Flow Meters

Types of Flow Meters

A flow meter is a flow rate measuring device used to determine the linear or nonlinear mass and volumetric flow of a liquid or a gas. The many names of flow meters include flow gauge, flow indicator, liquid meter, and flow rate sensor...

Metering Pumps

Diaphragm Metering Pump

A metering pump is a precision machine that moves or pumps a measured amount of fluid in a predetermined time to create volumetric flow. The term “metering pump” covers a wide range of pumping methods, each designed to meet...



A rotameter is a device that measures the flow of fluid volume per unit time in a closed tube. There are diverse rotameters applications, including chemical injection/dosing and tank blanketing. A rotameter can be said...

Water Filtering Systems

Water Filtering Systems

A water filtering system is a mechanism that is designed to remove solid particles, tiny or large, from inside a liquid through the use of a filter medium that only allows the liquid to pass but restricts solid particles....

Leak Detector

Leak Detector

A leak detector is a sensor used for monitoring a system that contains liquids, gasses, or other substances to ensure that the contained materials do not escape, leak, or otherwise leave the system. The leak detection process involves...

Centrifugal Pumps

Centrifugal Pumps

A centrifugal pump is defined as a hydraulic machine that changes mechanical energy into hydraulic energy by the use of centrifugal force acting on the fluid. This is a machine that uses rotation to enforce velocity on a liquid...

Flow Instrumentation

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