Volumetric Flow Meter, as a mechanical flow meter, is also called Positive displacement flowmeter. It can measure the volume flow of high viscosity and corrosive fluids.

Volumetric Flow Meters

Volumetric Flow Meter is a mechanical instrument used to measure the volume flow of fluids. A volumetric flow meter is an instrument which can measure either directly or indirectly the volume of a substance which is passing through a specific location in a set period of time. The main advantage of these types of flow meters is that they can handle high viscosity and corrosiveness fluid.

Sino-Inst offers a variety of Oval Gear Flow Meters for flow measurement. If you have any questions, please contact our sales engineers.

Featured Volumetric Flow Meters

Volumetric Flow Meter Types

As a mechanical flowmeter, the positive displacement flowmeter is characterized by no requirements for the front and rear straight pipes and high measurement accuracy. It is widely used in measuring viscous media such as oils.

Double-rotor flowmeter is the main variety of positive displacement flowmeter, with various forms and specifications, which can be used for the measurement of various liquid and gas media.

Oval gear flowmeter, its flow part is mainly composed of two elliptical gears meshing with each other and its shell (metering chamber).

Lumbar volumetric flowmeter is also called Roots-type volumetric flowmeter.
The working principle and working process of this kind of flowmeter are basically the same as the oval gear type. It also relies on the pressure difference between the inlet and outlet fluids to produce movement. Four parts of the fluid volume of the “metering space” are discharged every one rotation.
The difference is that there are no teeth on the waist wheel. They are not directly meshed with each other to rotate, but are transmitted through a transmission gear set installed outside the casing.

In the scraper type, the fluid pushes the scraper and the rotor to rotate, and the scraper extends and retracts radially along a special track.

The distance between the end faces of every two opposite scrapers is a certain value. When the scrapers rotate continuously, a fixed measuring chamber is formed between the two adjacent scrapers, the rotor, the inner cavity of the casing, and the upper and lower cover plates. In one circle, four (or six) metering chamber volumes are discharged, that is, the circulating volume.

According to whether the scraper is in contact with the cavity wall, it can be divided into two types: elastic scraper and rigid scraper. The front end of the elastic scraper is in elastic contact with the cavity wall, which is suitable for measuring liquids containing sand and other impurities.

The front end of the rigid scraper maintains a small fixed gap with the cavity wall, which is used for cleaning or liquid with fine powder impurities.

The structure of rigid scraper can be divided into groove type (British AveryHardoll type) and cam type (American Smith type).

Insert the ring piston into the shell of the two-layer cylindrical cylinder to form a form in which the ring piston rotates in the shell with the flow of liquid. The flowmeter has a diameter of DN20~100mm and a measurement degree of 0.5%R. It can be used for oil and food measurement. 6 reciprocating piston type. The piston reciprocates in the cylinder under the push of fluid to measure the volume flow. Usually, the fuel dispenser at the gas station is of this type, with a flow rate of 60L/min and a measurement degree of ±(0.15~0.3)%R.

Also known as Nutating Flowmeter, the disc with a center ball rotates and swings up and down in the measuring chamber, and the nutaTIon moves into and out of the liquid. Compared with other PDFs, the degree is poor and the viscosity has a greater influence .
There was a production to measure petroleum products in our country, but there were few applications. In North America, it is mostly used as household water meter and industrial water meter.

Also called wet gas meter, it is used to measure the total amount of gas.
About half of the sealing liquid (water or oil) is contained in the casing of the flowmeter, half of the rotating cylinder is immersed in the sealing liquid, and the gas flows in to make it rotate. The sealing form is no leakage.
The wide range is 20:1, the performance is stable, and the higher degree can be obtained under careful operation, which is ±(0.2~0.5)%R. It is mostly used in the laboratory and is often used as a meter or standard meter for value transmission.

With so many positive displacement flow meters, each has its own advantages and is used in different media measurement.

Common positive displacement flow meters are oval gear flow meters, double rotor flow meters, waist wheel flow meters and scraper flow meters.

However, volumetric flow meters are more expensive than ordinary electronic watches, especially large-caliber meters.

Volumetric flow meter working principle

The positive displacement flow meter is a flow meter that uses mechanical measuring elements to continuously divide the fluid into a single known volume, and repeatedly fill and discharge the volume of fluid to accumulate the total amount of fluid.

Volumetric flow measurement uses a fixed small volume to repeatedly measure the volume of fluid passing through the flowmeter.

Therefore, there must be a standard volume of space inside the positive displacement flowmeter, which is usually called the “metering space” or “metering chamber” of the positive displacement flowmeter.

This space is formed by the inner wall of the instrument case and the rotating parts of the flowmeter.

The working principle of a positive displacement flow meter is: fluid passing through the flow meter will produce a certain pressure difference between the inlet and outlet of the flow meter.

The rotating part of the flowmeter (referred to as the rotor) rotates under the action of this pressure difference, and discharges the fluid from the inlet to the outlet.

In this process, the fluid fills the “metering space” of the flowmeter again and again, and then is continuously sent to the outlet.

Under the conditions of a given flow meter, the volume of the metering space is determined. As long as the number of rotations of the rotor is measured, the cumulative value of the volume of fluid passing through the flow meter can be obtained. Flow rate of viscous fluids such as oils, condensate, resin and liquid food.

For the flow of high-viscosity media, other flowmeters are difficult to measure, but positive displacement flowmeters can accurately measure with an accuracy of ±0.2%.

Mass Flow Rate vs Volumetric Flow Rate-How to convert ?

  1. If the mass flow of the flow is known and needs to be converted into volume flow, the following formula can be used: qv=qm/ρ. In the formula, qv is volume flow, m3/s. qm is mass flow, kg/s. ρ is fluid Density, kg/m3.
  2. If the volume flow rate of the fluid is known, it needs to be converted into a mass flow rate, which can be done with the formula: qm=qv×ρ.

More: Mass Flow Rate vs Volumetric Flow Rate

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Sino-Inst, Manufacuturer for Volumetric Flow Meters. For example: crude oil flowmeter, diesel flowmeter, gasoline flowmeter.

Sino-Inst’s Volumetric Flow Meters, made in China, Having good Quality, With better price. Our flow measurement instruments are widely used in China, India, Pakistan, US, and other countries.

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Volumetric Flow Meters for Sale-Sino-Inst

Volumetric Flow Meter, as a mechanical flow meter, is also called Positive displacement flowmeter. It can measure the volume flow of high viscosity and

Product SKU: Volumetric Flow Meters

Product Brand: Sino-Inst

Product Currency: USD

Product Price: 500

Price Valid Until: 2059-09-30

Product In-Stock: InStock

Editor's Rating:
5

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