Flow Instruments

HomeFlow Instruments

Our partnership with Endress + Hauser enables us to offer flow measurement solutions in these technologies: Electromagnetic, Coriolis Mass, Ultrasonic, Vortex, and Thermal Mass.

Reliable flow measurement and control is required in almost all types of industries; from the food and pharmaceutical industries where hygiene is of paramount importance, to the chemical, oil, gas and petrochemical industries which require robust and reliable instrumentation to suit the hazardous conditions. Through our manufacturers, TriNova, Inc. offers a complete range of sensors and transmitters for virtually all aspects of flow measurement.

Flow Instruments

Our Manufacturers

Flow Instruments
Flow Instruments
Mass Flow Meters


A mass flow meter, also known as an inertial flow meter is a device that measures mass flow rate of a fluid traveling through a tube. The mass flow rate is the mass of the fluid traveling past a fixed point per unit time.

The mass flow meter measures the mass per unit time (e.g., kilograms per second) flowing through the device. Volumetric is the mass flow rate divided by the fluid density. If the density is constant, then the relationship is simple. If the fluid has varying density, then the relationship is not simple. The density of the fluid may change with temperature, pressure, or composition, for example. The fluid may also be a combination of phases such as a fluid with entrained bubbles. Actual density can be determined due to dependency of sound velocity on the controlled liquid concentration.

Differential Pressure

Continuous level, flow and differential pressure measurement

Differential pressure transmitters with piezoresistive pressure sensors and welded metallic membrane or electronic dp or diaphragm seal is used mostly in the process industry. Deltabar offers continuous level measurement in liquids as well as volume or mass flow measurement using primary elements. It is also possible to do filter monitoring with the differential pressure transmitter. Check out the broad range of Deltabar devices and click on the button below.

Pressure Gauge Products

Beside the devices with silicon or diaphragm seal for differential pressure, level, dp flow measurement, Deltabar electronic dp is a differential pressure system combining two sensor modules and one transmitter. In level applications, the high pressure sensor (HP) measures the hydrostatic pressure. The low pressure sensor (LP) measures the head pressure. The level or differential pressure is calculated in the transmitter using these two digital values.

Differential pressure measurement: Measuring Principle

Silicon cell: The operating pressure deflects the process isolating diaphragm and a fill fluid transfers the pressure to a resistance bridge (semiconductor technology). The pressure-dependent change in the bridge output voltage is measured and evaluated.

Diaphragm seal: The operating pressure acts on the process isolating diaphragm of the diaphragm seal and is transferred to the process isolating diaphragm of the sensor by a fill fluid.

Magnetic Flow Meter


Magnetic flow meters function under the principles of Faraday’s law of electromagnetic induction. According to this law, a conductor that passes through a magnetic field produces voltage proportional to the relative velocities between the magnetic field and the conductor. The law can be applied to flow meter systems because many fluids are conductive to a certain degree. The amount of voltage they generate as they move through a passage can be transmitted as a signal measuring quantity or flow characteristics.


Vortex Flowmeters

Vortex flow measurement: Robust and universally applicable for liquids, gases and steam

Vortex flowmeters are used in numerous branches of industry to measure the volume flow of liquids, gases and steam. Applications in the chemicals and petrochemicals industries, for example, in power generation and heat-supply systems involve widely differing fluids: saturated steam, superheated steam, compressed air, nitrogen, liquefied gases, flue gases, carbon dioxide, fully demineralized water, solvents, heat-transfer oils, boiler feedwater, condensate, etc.

Vortex flowmeters are also in widespread use for measuring mass flow. Therefore, modern vortex meters such as the multivariable Prowirl 200 are built for more than merely measuring volume flow, and come complete with temperature sensor and flow computer.

Unique Prowirl 200

Prowirl 200 is the world’s first vortex meter with the option of monitoring the steam quality and immediately generating an alarm message in case of wet steam. Prowirl 200 can also be used for flow monitoring systems up to SIL 2 and SIL 3 and is independently evaluated and certified by the TÜV in accordance with IEC 61508.

Vortex flow measuring principle

This measuring principle is based on the fact that turbulence forms downstream of obstacles in the flow, such as a bridge pier.

Inside each vortex flowmeter, a bluff body is therefore located in the middle of the pipe. As soon as the flow velocity reaches a certain value, vortices form behind this bluff body, are detached from the flow and transported downstream. The frequency of vortex shedding is directly proportional to mean flow velocity and thus to volume flow.

The detached vortices on both sides of the bluff body generate alternately a local positive or negative pressure that is detected by the capacitive sensor and fed to the electronics as a primary digital, linear signal.


Ultrasonic flowmeters

Versatile and economical flow measurement of gases and liquids up to a nominal diameter DN 4000

Using ultrasonic waves, the flow volume of a wide variety of gases and liquids can be measured reliably – independent of electrical conductivity, pressure, temperature, or viscosity.
In applications that require traceable and guaranteed accuracy, inline ultrasonic sensors are preferred for use. Clamp-on ultrasonic sensors, on the other hand, are installed on the outer wall of the pipe and thus also enable temporary measurements or a retrofitting.

Clamp-on sensors

For retrofitted installation without interrupting the process, Aggressive fluids can be measured without any problems, even under high pressure, Suitable for pipes made of plastic, steel, cast iron composite materials (lined/unlined), For pipe diameters up to DN 4000 (156″)


In-line sensors

Guaranteed accuracy thanks to traceable factory calibration, Robust industrial design in accordance with ASME and EN, Short inlet runs, For pipelines up to DN 300 (12″)


Other Flow Products

Oil Water Meters


Unlike other microwave, density or capacitance based instruments, Agar’s OW series meters are the only devices in which the accuracy of the measurement is not affected by changing salinity, density, viscosity, temperature or velocity of the components being analyzed. The high frequency signal will maintain accuracy in the presence of process coatings that would be detrimental to optical instruments.


Agar’s Multiphase Flow Meters are comprised of five primary subsystems:
  1. The mass flow and density measurement is based on coriolis and other ancillary sensors.
  2. The AGAR Water-cut meter (OW-201 or OW-301) is used to measure water content accurately over the full range of 0-100% in both oil and water-continuous phases.
  3. The AGAR Data Analysis System (DAS) performs on-line analysis of data acquired from the above sub-systems to determine the oil, water, gas, and total fluid flow rates.
  4. High Flow Rate Capability: In applications where the flow line is larger than 4″ and the flow rate is high, Agar’s unique flow range extender (F.R.E.) MPFM-50 design is used.
  5. The Agar Dual Venturi Meter is used to measure flow rates of the multiphase in extreme conditions where the flow is not homogeneous.

Optical Flow Meters


Optical flow meters are very stable with no moving parts and deliver a highly repeatable measurement over the life of the product. Because distance between the two laser sheets does not change, optical flow meters do not require periodic calibration after their initial commissioning. Optical flow meters require only one installation point, instead of the two installation points typically required by other types of meters. A single installation point is simpler, requires less maintenance and is less prone to errors.

Laser-based optical flow meters measure the actual speed of particles, a property which is not dependent on thermal conductivity of gases, variations in gas flow or composition of gases. The operating principle enables optical laser technology to deliver highly accurate flow data, even in challenging environments which may include high temperature, low flow rates, high pressure, high humidity, pipe vibration and acoustic noise.


A flow totalizer measures the amount of liquid or gas that flows through a pipe. Flow totalizers come in a variety of styles, and they are used in a wide variety of applications. By recording the results of the totalizer and dividing the amount over a quantity of time, you can determine the average flow rate of a pipe. At Vector Controls, we know that measuring the amount of liquid used in your applications is important for the bottom line, especially when dealing with expensive substances and potentially, extremely costly waste.