Liquid flowmeter: characteristics and description. Which firm to buy a liquid flow meter?

Enterprises that work in a variety of industries, use in their production devices called flowmeters. Using ultrasound, they can take into account the amount of water consumed or other liquids.

The need for a flowmeter

This device is needed in order to easily measure the amount of consumed substance for a certain period of time. Most often, those who use pipelines keep a record of the amount of fuel, liquid and gas. It is interesting to note that such devices are used not only in industry, but also in everyday life, for example, you can find out the water flow in the house.

How to choose the right device?

In order to correctly choose a liquid flow meter, it is necessary to clearly understand the basic requirements that will be presented to it. Therefore it is important to know the technological parameters and the entire process of its installation.

Here is a list of key issues that need to be clarified before purchasing such a device:
1. What kind of environment (water, air, gases, etc.)?
2. What needs to be measured (total and / or instantaneous flow, speed)?
3. If the liquid is not water, then what is its viscosity?
4. Is there a requirement for a local / local display, or will an electronic liquid flowmeter be required that automatically outputs the signal to the screen?
5. What is the maximum and minimum speed of the source stream?
6. Is the liquid that is inside, chemically compatible with the internal surfaces, namely the parts in contact?
7. The size of the installed pipe?
8. The maximum and minimum pressure and temperature of the press?
9. Is the liquid that is measured clean?

Ultrasonic flowmeters

The ultrasonic flowmeter uses for its work waves that, during recording, change the propagation velocity in a moving medium. In the case of the installation of a source and receiver of ultrasound with a shift in the flow velocity, one can judge as the sound wave changes along the entire length.

To measure the local tempo, you can use the Doppler effect, for this you need to place the source and receiver in parallel, in this case the signals are transferred to the mixer.

The ultrasonic flowmeter fixes its frequency on the receiver and changes it depending on the speed of the entire flow, and the initial frequency remains unchanged. The multiplicity of the signal from the mixer at the output is the difference between the frequencies of the received and the initial motion. By this value, one can also judge about the local velocity in matter.

Portable flowmeter

There is also a portable liquid flow meter, which is ultrasonic. This device, fully equipped with additional accessories and accessories, which allow you to solve a variety of tasks to measure the amount of liquid in virtually any environment. It helps to account for substances with a viscosity of up to 300 cSt in almost completely filled pipes with a diameter of 1.2 to 5 cm. The initial kit can include:
- electronic single-channel calculator;
- overhead and stationary converters of various types and systems for their installation;
- accessories for measuring the energy of heat flow and resistance thermometers;
- ultrasonic sensors for calculating the pipe wall thickness;
- Thermal printer with accessories included in it;
- software for IBM PC, which is fully compatible with the computer;
- power supply unit and all accessories that are included in it.

Electromagnetic flowmeter

The electromagnetic flowmeter is designed for measuring substances that conduct electricity. It consists of a measuring tube having a rigid channel section and made of a dielectric material. On the external surface there is a magnetic circuit, which looks like two inductors. Also, four electrodes are mounted - two in the vertical, and two in the horizontal plane in relation to the measuring tube itself. Vertical electrodes are necessary to account for electrical conductivity in the pipeline. A sensor that calculates a magnetic field inside a pipe channel is installed on its surface. It is located in a steel casing, on the post of which the electronic unit is attached. All the wires are outputted to it and then they are decoupled from the PCB. The external connection moves to the connectors that are located on this housing. On the coils and electrodes mount metal screens that do not react to the magnet, then they must be grounded. The end seal is performed with a rubber ring. Due to this, it is possible to achieve such a technical result, in which high accuracy and stability of operation are realized, as well as reliable operation over a wide range of pressures and temperatures.

Doppler flowmeters

Such a liquid flowmeter is intended for measuring a medium that contains sound reflectors, namely gas bubbles or suspended matter. These devices are produced in three different forms. The family of meters includes both non-invasive devices and input probes for applications that are used for pipes with insufficiently good ultrasound transmission.

The standard characteristics of such devices are:
- structures that have fixatives;
- programmable interface;
- 8-digit LCD counter;
- power supply with adjustable characteristics;
- case with good protection;
- Pipe sizes can vary from 0.25 inches to 6 mm;
- additional double outputs;
- pulse repetition rate and relay output.

Mechanical counter

A mechanical fluid flowmeter is an instrument in which electronic components are completely missing. They can measure the flow rate, for example, the speed of a mechanical turbine when it is immersed in a medium. Very often such devices are used on dryers, diesel generators, burners and in boiler rooms.

A mechanical meter is a flowmeter for a viscous liquid, so it is used to account for processed petroleum products. All devices are perfect for measuring fuel, which moves by gravity. The standard device in its kit has a mechanical roller counter, also complete with LCD display or pulse output. The meter itself and all the places of its connection are sealed, in order to avoid the peculiar twists of the testimony that the people of our country love so much.

Thermal flowmeters

The thermal flowmeter of a liquid has a fairly simple idea in its work: if we locally measure the properties of a substance in a stream, say it is the temperature, and start recording all changes at a certain location from the impact zone, then we can fix the average velocity of any substance. If the medium is stationary, then the temperature begins to rise only due to thermal conductivity, and this process occurs faster, as it is closer to the heating element. With this analysis of data collected from all sensors, it is possible to determine the velocity of the substance in any flow.

Vortex flowmeters

A liquid flowmeter of this type has in its design a main element, which is a spherical or disk-shaped target mounted on an elastic cable, one part of which is fixed immovably. Streams of gas or liquid lead to the fact that the target is displaced, which causes the cable to move, and the strain gages that are attached to it register the degree and type of deformation. The data that are obtained allow one to judge the speed of movement in a substance, as well as its direction.

The main advantages of such sensors is the possibility of carrying out all measurements in several directions, in which the flowmeter used is operating. The liquid counter, in order to provide such multitasking, has symmetrical targets for all necessary directions.

Coriolis flowmeters

Most often, these flow meters consist of a tube, to which a vibrating effect is applied from an external oscillator. If it is empty, jiggling can lead to synchronous acceleration of all its sections. If liquid moves through the tube, it will also be affected by the Coriolis force, which is sent to different sides for the output and input stream, and this will lead to a shift in the oscillation periods. The magnitude of phase mismatch depends primarily on the mass of the liquids being measured, which flow per unit time.

The main advantage of these devices is their versatility - they can be used to measure the flow rate of a sufficiently large range of substances. But there is a drawback - this is their high cost, which can afford mainly large enterprises.

Micronics Flowmeters

Reducing the amount of liquid is an important factor that characterizes the energy efficiency of buildings and objects. This well-known brand is widely represented by portable liquid flow meters, which do not require tapping into the pipeline. Portaflow 330 series provides an accurate and fast measurement of the amount of raw material consumption, and it is characterized by its ease of operation, thanks to the intuitive menu and adjustment possibilities during operation. The very procedure for measuring takes literally a few minutes. The devices are compact enough and reliable, and also differ in their stable performance characteristics with a fairly long use in the production.

The basis of the Micronics flowmeters is the so-called time-of-flight technique, with which it is possible to measure the frequency of the two-dimensional propagation of ultrasound, which are emitted by special sensors fixed to the tube. The speed of the signal passing through the liquid in the pipe becomes larger in the case of the direction of the signal along the stream, and in the opposite direction the indices do not coincide and the speed of the ultrasonic signal decreases.

Siemens Flowmeters

This brand represents both stationary and overhead liquid flow meters. To date, the MAG 5100w is considered to be the leading sensor. It is a compact device with very precise characteristics. It is used for instantaneous measurements of clean and waste water. For its operation, it will be necessary to supply a power source of 220 or 24V, as well as a completely filled pipeline. If it is empty, the device will show it using a relay. The transducer is most often installed on top of the sensor, but you can also use an additional mounting kit that contains the cable so that the device can be remotely controlled. It is also important that it is possible to seal devices, thereby increasing the protection class to IP68. Due to this, it can be used for a long enough dive or flooding.

The main advantages of Siemens flowmeters

- High repeatability and accuracy gives complete confidence in accounting for all flows.
- The devices have a high-quality and solid construction, without parts that move. This means that wear is very slow, therefore maintenance will not take a long time.
- There is a pipeline fill monitoring that will warn of the operation of the device in an unfilled pipe, thereby reducing the likelihood of erroneous measurements.
- The backlighting of the keyboard and display helps the user to easily monitor all settings and measurements.
- Bi-directional flow accounting provides the user with all information about the movement in the pipeline.
- SENSORPROM ™ technology guarantees automatic metrological readings of the device.
- The flow convector is installed compactly or remotely using brackets that are fixed to the sensor.

Most often used for measuring sewage or drinking water, as well as for accounting liquid for chillers and test benches.

Having considered two firms producing sensors, one can conclude that each of them deserves to exist in the market, since Micronics and Siemens are engaged in counters for different purposes. Both brands are responsible for their high quality and long service life due to the fact that they have been developing and introducing new technologies in this industry for several years already.