Chemical Flow Meter Guide

What is Chemical Flow Meter?

Chemical Flow Meter is also known as chemical resistant flow meter. It is a flow meter used to measure common chemical fluid media. In chemical production control and metering, between chemical reaction storage tanks, or chemical raw material feed pipelines.

Sino-Inst offers a wide range of liquid and gas flow meters to help you regulate the flow of water, petroleum products, fuels, chemicals and more.

So how do choose the most suitable Chemical Flow Meter? Hope you can find the answer after reading this article.

Featured mechanical & digital flow meter for chemicals

If you want to choose a suitable chemical flow meter, you must first understand the characteristics of the chemical raw materials you need to measure.

According to different forms, chemical raw materials can be divided into solid chemical raw materials, liquid chemical raw materials, and gas chemical raw materials. There are many liquid and gas chemical raw materials, and most of them are corrosive. Special attention should be paid to them during transportation and storage.

The chemical flow meter mainly measures gas and liquid chemical raw materials.

Common characteristics of chemical fluids that need to be considered when measuring flow rate:

  1. Corrosive

This is the most common characteristic of chemical materials. Corrosive acid, alkali, salt solution.

  1. Flammable and explosive

Compared with flammable liquids and solids, flammable gas is easier to burn, and the burning speed is fast, and it burns out. Gas composed of simple components is more flammable, the faster-burning rate has higher flame temperature and greater risk of fire and explosion than gas composed of complex components.

  1. Electrified

Most flammable liquids are electrolytes. Such as crisps, ketones, gasoline, esters, aromatics, and petroleum products.

These substances are transported, poured, shaken, stirred, and flowed at high speeds in pipelines, storage tanks, tank trucks, and oil tankers.

Because friction is easy to generate static electricity, when the static charge accumulated to a certain extent, static sparks will be generated, which may cause burning and explosion.

  1. Stickiness

Such fluids include glue, resin, asphalt, and molasses.

Gear Flow Meter – A New Choice for Chemical Liquids

Gear Flow Meters produced by Sino-Inst has high machining accuracy and precise installation. The rotation of the gear is scanned by non-contact. Each tooth produces a pulse. The resolution is very high. The cylindrical gear transmitter can measure very small flow. Quantitative small volume of liquid.

The new Gear Flow Meter made of PTFE is widely used in the chemical industry and laboratories. 98% nitric acid and sulfuric acid resistant to hydrofluoric acid. It has not been corroded after long-term continuous use.

Gear Flow Meter is suitable for:

  • Resin and glue measurement
  • Hydraulic oil, lubricating oil, grease measurement
  • Fuel oil measurement
  • Ink, asphalt measurement
  • Liquid nitrogen, freezing liquid, solvent measurement
  • Edible oil, fish oil and food filling measurement
  • Chemical and anti-corrosion requirements fluid measurement
  • Fluid quantitative control system

Extended reading: High-quality hydraulic fluid flow meters

Chemical flow meters types

The following will explain the flowmeters commonly used in the chemical industry.

  1. Electromagnetic flowmeter. When a conductive fluid flows through an electromagnetic field, the velocity of the fluid can be obtained by measuring the voltage. The electromagnetic flowmeter has no moving parts and is not affected by the fluid. The accuracy of measuring conductive liquids when the tube is full is very high. The electromagnetic flowmeter can be used to measure the flow rate of the slurry fluid.
  2. DP flowmeter can be used to measure the flow rate of most liquids, gases and steam. Positive displacement flow meter (PD). The PD flowmeter is used to measure the volumetric flow rate of liquid or gas. It introduces the fluid into the measuring space and counts the number of rotations. Impellers, gears, pistons or orifices are used to divert fluids.
  3. Vortex flowmeter. The vortex flowmeter is to place a non-streamlined vortex generator in the fluid, and the speed of the vortex is proportional to the speed of the fluid to calculate the volume flow. The vortex flowmeter is suitable for measuring liquid, gas or steam. It has no moving parts and no fouling problem. The vortex flowmeter generates noise and requires the fluid to have a higher flow rate to generate the vortex.
  4. Thermal mass flow meter. The fluid velocity is measured by measuring the increase in the temperature of the fluid or the decrease in the thermal sensor.
  5. Coriolis flowmeter. This kind of flowmeter uses a vibrating fluid tube to produce a deflection corresponding to the mass flow rate for measurement.
  6. Turbine flowmeter. When the fluid flows through the turbine flowmeter, the fluid causes the rotor to rotate. The rotation speed of the rotor is related to the speed of the fluid. From the average flow rate of the fluid felt by the rotor, the flow rate or total amount is derived.
  7. Ultrasonic flowmeter. The propagation time method and the Doppler effect method are methods often used in ultrasonic flowmeters to measure the average velocity of the fluid. Like other speed meters, it is a meter that measures volume flow.

Electromagnetic flowmeter F4, F46, PFA, rubber lining

Electromagnetic flowmeters can measure the flow of general conductive liquids. It can also measure the volume flow of liquid-solid two-phase flow, liquid with high viscosity, strong acid, strong alkali, and salt liquid medium.

For chemical liquids, as long as they are conductive liquids, electromagnetic flowmeters can measure them.

But we need to choose the appropriate lining and electrode according to the characteristics of the chemical liquid.
You can refer to the liner and electrode material usage table below.

Lining material selection:

Lining material


Main performance





1. It has excellent flexibility. High tearing force. Good wear resistance.
2. Resistant to the corrosion of low-concentration acid, alkali, and salt media. Not resistant to corrosion by oxidizing media.

1. <60℃
2. General water, sewage, mud and mineral slurry with weak abrasiveness


Polyurethane Rubber(PU)

1. It has excellent wear resistance (equivalent to ten times that of natural rubber)
2. Poor acid and alkali resistance.
3. It cannot be used for water mixed with organic solvents.

1. <80℃
2. Neutral and strong abrasion ore slurry, coal slurry, mud, etc.


Silicone rubber

1. It has excellent flexibility. High tearing force. Good wear resistance.
2. High temperature resistant non-corrosive medium.

1. <180℃
2. Hot water




1. It is a material with the most stable chemical properties in plastics. Can withstand boiling hydrochloric acid, sulfuric acid, nitric acid and aqua regia. It is also resistant to concentrated alkali and various organic solvents. Not resistant to the corrosion of chlorine trifluoride, high temperature oxygen trifluoride, high flow rate liquid fluorine, liquid oxygen, and ozone.
2. Poor wear resistance.
3. Poor anti-negative pressure ability.

1. <120℃
2. Strong corrosive media such as concentrated acid and alkali
3. Sanitary medium


Teflon F46(FEP)

1. The chemical properties are equivalent to PTFE
2. Tensile strength and abrasion resistance are better than PTFE
3. Can withstand high pressure resistance.

1. <180℃
2. Corrosive acid-base salt
3. High pressure and negative pressure resistance



1. The chemical performance is equivalent to F46
2. Compressive and tensile strength due to F46

1. <180℃
2. Corrosive acid-base salt
3. High pressure and negative pressure resistance


Electrode material selection:

316LDomestic water, industrial water, raw water, urban sewage, etc.
Hastelloy B (HB)Sodium hydroxide ammonium hydroxide alkali solution and weak organic acid
Hastelloy C (HC)Oxidizing salt solution (Fe+++, Cu++, seawater)
Titanium (Ti)1. Salt solution (chloride, sodium salt, potassium salt, ammonium salt, sea water, etc.)
2. Alkaline solution (such as concentration less than 50% potassium hydroxide solution)
Tantalum(Ta)1. Hydrochloric acid, sulfuric acid, oxidizing acid, aqua regia
2. Chlorine dioxide, ferric chloride, hypochlorous acid, sodium cyanide, lead acetate, etc.
Platinum (Pt)Acid, alkali, salt solution
Tungsten carbide (WC)Handled neutral industrial sewage and domestic sewage. Resistant to solid particle interference

Guess you will like: Magnetic Flow Meters technical guide|What is &How they work? 

Of course, in addition to electromagnetic flowmeters. To measure acidic media, oval gear flowmeters, vortex flowmeters, and turbine flow sensors made of acid-resistant materials can also be used. The parts in contact with the medium are made of acid-resistant materials, which can resist general acidic substances.

Such fluids include solvents, solutions, ethanol, diesel, and clean water.

Turbine flow meters are less expensive and usually have chemical flow sensors that have a compact design.

These flow meters are volumetric, meaning that they can measure liquids passing through them either indirectly or directly.

Some of the advantages of using turbine flow meters are that they have high accuracy, can measure high pressure, and have a large measuring range.

When the clamp-on ultrasonic flowmeter is working, the liquid does not directly contact the flowmeter. So it is suitable for various corrosive liquids. But its accuracy rate is relatively low.

Extended reading: Sludge flow meter for sewage treatment return activated sludge system

Commonly used chemical liquid-flowmeter recommendation

Chemical FluidsAvailable Flow Meters
Sulfuric acidElectromagnetic flowmeter, PTFE gear flowmeter
Acetic acidElectromagnetic flowmeter, PTFE gear flowmeter
Hydrochloric acidElectromagnetic flowmeter, PTFE gear flowmeter
Chemical sewageElectromagnetic Flowmeter
Liquid nitrogenCryogenic turbine flowmeter
Hydrogen peroxideElectromagnetic Flowmeter
AsphaltGear flow meter

Of course, the choice of flowmeter also needs to be determined according to the actual measurement parameters.

More chemical liquid flow measurement solutions

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Sino-Inst, Manufacturer for Chemical Flow Meters. These chemical flow meters are easy to use and install on hose ends, pumps or fluid transfer systems. These chemical flow meters are designed for today’s pesticides, fertilizers, and many other chemicals.

Each chemical flow meter has different measurement materials and different measurement characteristics. Compatible with other chemical liquids or oils.

Sino-Inst’s Chemical 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.

If you are not sure which chemical flow meter is right for your measurement? Please feel free to contact our sales engineers. Based on years of experience in measuring chemical fluid flow, we will help you find the right chemical flow meter.

Cryogenic Pressure Transducers

Cryogenic pressure transducer for low temperature pressure measurement.  -196℃~+125℃、-260℃/-350c(especial).

The Cryogenic pressure transducer adopts a stainless steel integrated packaging structure, and the pressure-sensitive diaphragm adopts an excellent special design. It works safely and stably in an ultra-low temperature -196℃ environment. Used for cryogenic scientific experiments such as liquid oxygen/liquid nitrogen/liquid hydrogen/cooling tank/recommendant/low temperature storage tank.

Sino-Inst offers a variety of Pressure Sensors for pressure measure and control. If you have any questions, please contact our sales engineers.

What is Cryogenic pressure transducer?

The Cryogenic pressure sensor adopts a stainless steel integrated packaging structure, and the pressure-sensitive diaphragm adopts a special design. This can make the sensor work stably in an ultra-low temperature -196 degrees Celsius environment.

Its advantages are small size and extremely high measurement accuracy. It brings convenience to scientific research work, high dynamic response frequency, strong corrosion resistance and long working life.

Even if the purchase cost is high, the later use value is much higher than its own value. In the future of technological development, low-temperature pressure sensors will be used more and more widely.

Read more about: What is industrial pressure transmitter?

Features of Cryogenic Pressure Transducer

  • 0-5vdc, 0-10vdc, 4-20mA Signal output optional
  • -196℃~+125℃、-260℃/-350c(especial)
  • Stainless Steel Construction
  • IP65 or IP67 enclosure
  • Product range: 0-2000bar

Extended reading: cryogenic fuel level indicator

Parameters of Cryogenic Pressure Transducer

Product range: 0-2000bar
Temperature: -196℃~+125℃, -260℃/-350c (especial)
Signal output: mv, 0-5vdc, 4-20mA, Hart, Rs485
Range: 0~0.2MPa…15MPa…60MPa Pressure type: absolute pressure, gauge pressure
Working voltage: 5-15VDC (10VDC) / 9-36vdc
Signal output: 0-5vdc, 0-10vdc, 4-20mA
Zero output: ±5%FS (typical)
Full load output: 10mV, 20mV, 100mV option
Linearity: 0.1%FS, 0.2%FS
Repeatability: 0.05%FS
Accuracy: ±0.25% FS, ±0.5% FS (default)
Room temperature: 0.1% FS, 0.2% FS, 0.5% FS
Low temperature: 0.5% FS% ~ 3% FS
Working temperature: -196℃~+125℃, -260℃/-350c (especial)
Low temperature zero drift: 1 ~ 4% FS (full-temperature zone)
High temperature zero drift: 1 ~ 4.5% FS (full-temperature zone)
Response frequency:> 1kHz or> 5kHz optional
Insulation resistance: ≥ 100MΩ/50V
Safe overload: 150% FS (1.5 times full scale)
Limit overload: 300% FS (3 times the full scale)
Vibration: 5 ~ 1000Hz, amplitude 2mm, X, Y, Z each to 30 minutes, the output changes less than 0.1% FS
Thread: M3, M4, M5, M6, M8, M10, M12 × 1 or a designated
Measuring medium: liquid oxygen/liquid nitrogen/liquid hydrogen, etc.
Humidity: 95% RH
Waterproof rating: IP65 or IP67 enclosure

Extended reading: Pressure indicator transmitters

Application of Cryogenic pressure transducer

Cryogenic pressure transducer has small size, high measurement accuracy, high dynamic response frequency, strong corrosion resistance and long working life.

Our professional technical group provides you with customized services. This product is mainly used for: low temperature scientific experiment, liquid

Oxygen, liquid nitrogen, liquid hydrogen, liquid helium, etc. Pressure and low temperature measurement of cooling tanks, cryogenic storage tanks, propellants, etc.
Cryogenic storage tanks for aerospace, aviation, naval vessels, etc.

If you need to measure not liquefied nitrogen and liquefied oxygen, but gas nitrogen and oxygen. You can refer to:

Industrial oxygen flow meters Nitrogen flow measurement

Extended reading: Cryogenic Flow Meters | Liquid Nitrogen-Liquid Oxygen

More Featured Pressure Transmitters

Extended Reading: Resistive Pressure Transducer

Sino-Inst offers over 20 Pressure sensors. A wide variety of  Pressure sensors options are available to you. Such as free samples, paid samples. Sino-Instrument is a globally recognized manufacturer of Pressure sensors, located in China.

Sino-Inst sells through a mature distribution network that reaches all 30 countries worldwide. Pressure sensors products are most popular in Europe, Southeast Asia, and Mid East. You can ensure product safety by selecting from certified suppliers. With ISO9001, ISO14001 certification.

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Karman vortex air flow sensor VS Mass air flow sensor

Karman vortex air flow sensor is a commonly used flow meter for measuring air. Karman vortex air flow sensor is also called vortex shedding flow meter.

There are many types of instruments that can be used to measure air, but the actual air flow rate used in the field is divided according to its principles, and there are not many types. Karman vortex air flow sensor and Mass air flow sensor are two commonly used.

Which one should you choose?

What is a Karman vortex air flow sensor?

Karman vortex air flow sensor is a volume flow meter.

Karman vortex air flow sensor uses airflow to bypass a cone and generate two rows of vortices downstream. The vortex frequency has a functional relationship with the intake air flow. An instrument that determines the air flow by detecting the frequency of the vortex by optical or ultrasonic methods.

Extended Reading: Digital air flow meters

What is a mass air flow sensor ?

The mass air flow sensor is a mass flow meter. Also called Thermal gas mass flow meters.

Thermal gas mass flow meters are instruments that use the principle of thermal diffusion to measure gas flow. The sensor is composed of two reference thermal resistance (RTD).

Thermal gas mass flow meter can measure air, nitrogen, carbon dioxide, methane, etc.
A single component or a mixture of certain components. The flowmeter is generally verified with ammonia or air as the medium when it leaves the factory.

Guess you like: Gas Mass Flow Meter

Karman vortex air flow sensor VS Mass air flow sensor

NameKarman vortexMass
Measurement PrincipleThrough measuring frequency of
turbulences behind an obstacle to
reflect the velocity of the gas, so
measures the actual volume flow of
the gas .
Measures the mass flow of the gas
via measuring the energy
needed to keep a heated resistor
at a constant temperature.
Temperature and Pressure CompensationTo calculate the standard volumetric flow , need temperature and pressure compensation . ( Requires temperature and pressure measurement additionally )There is a fixed relationship
between standard flow and mass flow (Be determined by the density of gas under standard condition ) , no need the temperature and pressure compensation.
SensitivityNo response to the flow less than 4 m/s.Can measures the flow small to 0 m/s.
Measure Ranges4-75 m/s0-224 m/s
Main factors affecting measurement accuracyvibrate(a slight shaking can affect the measuring accuracy a lot)
The cleanliness of the measured gas (No long-term measurement behind the air compressor)
Repair and
Can not install or uninstall under pressure, high cost of repair or calibration.Can install or uninstall under pressure,low cost of repair or calibration.

Extended reading: Volumetric Flow Rate To Mass Flow Rate

Applicaitons :

The Karman vortex air flow sensor is widely used, gas, liquid, and steam can be measured.

The Mass air flow sensor can only measure gas;


Karman vortex air flow sensor is much cheaper;

Installation conditions:

The vortex flowmeter has requirements for the installation of the straight pipe section of the measuring pipeline, generally the first 10 and the back 5.

The thermal mass flow meter has no limitation.


  1. Thermal gas mass flow meters have the following technical advantages:

A true mass flow meter does not require temperature and pressure compensation for gas flow measurement. The measurement is convenient and accurate. The gas mass flow or standard volume flow can be obtained.

Wide range ratio, can measure gas with flow rate as high as 120Nm/s and as low as 0.1Nm/s. Can be used for gas leak detection.

Good seismic performance and long service life. The sensor has no moving parts and pressure sensing parts, and is not affected by vibration on measurement accuracy.

Easy to install and maintain. If site conditions permit, installation and maintenance can be achieved without stopping production. (Need special customization)

Digital design. Integral digital circuit measurement, accurate measurement and convenient maintenance.

Using RS-485 communication can realize factory automation and integration.

Oxygen, nitrogen, hydrogen, road gas and multi-component gas measurement.

Blast furnace gas and coke oven gas measurement.

Gas flow measurement for natural gas, liquefied gas, flare gas, etc.

Primary air and secondary air flow measurement of power plant blast furnace.

Flow measurement of underground ventilation or exhaust system in mines.

Flue gas measurement.

Compressed air measurement.

Extended reading: Gas mass flow controller working principle

  1. The vortex flowmeter has the following advantages:

The output signal is not affected by the temperature, pressure, and density components of the fluid, and is directly proportional to the fluid flow rate.

The sensing element does not contact the medium and has high reliability.

No moving parts, simple and firm structure.

Wide measuring range and high precision.

The pressure loss is small and the energy saving is significant.

Read more about: Vortex Shedding Flow Meter Working Principle

More Featured Air flow sensors

Extended reading: What is an air pressure transducer?

Sino-Inst’s air flow sensor offer reliable and accurate volume flow measurement in a large range of sizes and pressure rating while being fully compliant with international standards.

Sino-Inst is the risk-free choice for your gas flow measurement applications.

Sino-Inst supplies air flow sensors, like: gas turbine flow meter. vortex flowmeter, thermal mass flow meter, and more. More about Types Of Air Flow Measurement Instruments.

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

Oil Level Measurement Solutions for the Oil & Gas Industry

Oil Level measurements are necessary to control the amount of oil in the tank and to prevent overflow. Oil Level measurements are very important in the process of oil and gas storage and transportation. We will analyze and introduce the automatic level measurement here. Hope to help you!

The Necessity of Oil tank level measurement

-In the process of oil and gas storage and transportation, accurately measure the height of the liquid level in the large oil storage tank. This is an important measure to correctly calculate oil storage, determine inventory, and calculate transportation.

-In oil and gas production, especially in oil and gas gathering, transportation, storage, and transportation systems, oil, natural gas, and associated sewage must be separated, stored, and processed in various production equipment and tanks. The measurement and control of the level are essential to ensure normal production and equipment safety. Otherwise, a major accident will occur.

-For example, if the oil tank level measurement is not well controlled, there will be evacuated or oil spill “roofing” accidents. If the liquid level of the oil-air separator is too high or too low, “oil running” and “gas blow-by” accidents will occur. Seriously affect the production and safety of subsequent equipment;

-The high oil-water interface in the electric dehydrator will destroy the electric field. If it is low, it will carry oil in the water and affect production.

The Basic Concept of Level

  • Level—refers to the general term of the liquid level of the liquid medium, the level of solids or the level of particles in the container and the interface between two different liquid media.
  • Liquid level-the height of the liquid medium in the container
  • Material level-the accumulation height of solid or granular substances in the container
  • Interface level – the level of the interface of two immiscible liquids medium

Extended Reading: How to Measure Volume of Liquid

Classification of Oil Level Measurement

According to the measurement method, it can be divided into continuous measurement and fixed-point measurement.

According to its working principle, it can be divided into the following types:

  1. Direct reading type It measures the liquid level based on the principle of fluid connectivity.
  2. Buoyancy type It measures the liquid level according to the principle that the height of the float changes with the height of the liquid or the buoyancy of the liquid to the float (or sinker) immersed in the liquid changes with the height of the liquid. The former is called constant buoyancy, and the latter is called variable buoyancy.
  3. Differential pressure type (static pressure type) It measures the level according to the principle of the change in the static (differential) pressure generated at a certain point by the change in the height of the liquid column or the material accumulation.
  4. Electrically, it measures the level based on the principle of converting level changes into various changes in electricity.
  5. Nuclear radiation type It measures the liquid level based on the principle that when the nuclear radiation of the isotope rays penetrates the material, its intensity changes with the thickness of the material layer.
  6. Acoustic It measures the level according to the changes in acoustic impedance and reflection distance caused by changes in the level

Read more about: 7 Level Senors for Tank Level Measurement 

Direct measurement is one of the simplest and most intuitive measurement methods. It uses the principle of communicating devices. The liquid in the container is introduced into an observation tube with a ruler. Read the height of the liquid level by the ruler

Such as a glass tube level gauge.

Extended Reading: GWR Level Sensor for High Temperature & High Pressure

Manual gauge level measurement is a basic method for measuring the volume and quality of liquids in various storage tanks.

It has the characteristics of simple operation, accurate measurement, and no auxiliary equipment. It is still the main measurement method in the crude oil gathering and transportation process of various oil fields.

When measuring with a gauge, first measure the height of the liquid level in the tank, and then calculate the volume and mass of the liquid in the tank according to the cross-sectional area of the tank or the large tank volume table.

The tool used by the gauge to measure is steel tape with a copper weight on the lower end. In order to facilitate the oil measuring operation, an oil measuring port is provided on the top of the tank. An oil measuring pipe is installed under the oil measuring port, and a hole is drilled at the bottom end of the pipe to communicate with the liquid. The purpose of setting the oil measuring pipe is to reduce the influence of the liquid level fluctuation in the tank on the oil measuring.

Extended reading: High Temperature Flow Meter

The magnetic flip level gauge has a firm structure, reliable work, and an eye-catching display.

Since the measured liquid is completely sealed and magnetic coupling transmission is used, it can measure high temperature, high pressure, and opaque viscous liquids, such as crude oil, sewage, etc.

The disadvantage is that after long-term use, the magnetism of the magnetic steel is degraded. Wear of the flap shaft can easily cause the wrong indication
Therefore, it should be checked and corrected regularly.

Extended reading: Industrial Tank level indicators and Tank Level Gauges

The buoyancy method to measure the liquid level is based on the principle of force balance, usually with the help of floats. The float is made into a hollow rigid body so that it can float on the liquid surface when it is balanced. When the liquid level changes, the float will move up and down with the liquid level. Therefore, by measuring the displacement of the float, the amount of liquid level change can be known.

Float type level gauges can be divided into float type, float type, etc. according to different float shapes;

According to different institutions, it can be divided into steel belt type and lever type.

Extended reading: What is a capacitive liquid level sensor?

It is measured based on the pressure generated by the weight of the liquid.

Since the static pressure generated by the liquid on the bottom surface of the container is proportional to the height of the liquid level. Therefore, the liquid level can be calculated by measuring the pressure of the liquid in the container.

Extended Reading: Petroleum Flow Meter

Ultrasonic level gauges use the propagation characteristics of waves in the medium.

Therefore, install an ultrasonic transmitter and receiver at the bottom or top of the container. The emitted ultrasonic waves are reflected at the phase interface. And it is received by the receiver. The time difference between ultrasonic wave transmission and reception is measured. The liquid level can be measured.

Read more: Guide: Non-contact Ultrasonic Level Sensing transmitters

According to different working principles, the electrical method can be divided into resistive, inductive, and capacitive.

Using electrical methods to measure frictionless parts and movable parts, signal conversion and transmission are convenient. It is convenient for remote transmission, reliable work, and the output can be converted into a unified electrical signal. Used in conjunction with the electric unit combination instrument. Can easily realize automatic detection and automatic control of liquid level.

Extended reading: Non Contact Liquid Level Sensor Working Principle

Radar level transmitters use radar technology to perform the non-contact continuous level measurement. The radar level indicator converts the level into an electrical signal. The level signal output can then be utilized by other instrumentation to monitor or control. Liquids and solids are commonly measured with this measuring technique. Like: Fly ash silo. Radar level sensors are divided into Pulsed radar technology and frequency modulated continuous wave (FMCW) radar level sensors.

Sino-Inst produces a 120GHz FMCW radar level sensor, 26GHz radar level meter, 6GHz level meter.

The magnetostrictive liquid level sensor that uses the principle of magnetoelectric conversion for liquid level measurement is a new product launched in recent years.

Extended reading: Diesel fuel tank level gauges & indicators

Still have questions?

If you cannot find an answer to your question in our FAQ, you can always contact us
and we will be with you shortly.

Performance characteristics and selection of common oil tank level gauges

The intermediate tank only monitors parameters such as liquid level, temperature, and pressure (pressure storage tank) to prevent accidents such as roof capping and vacuuming of the oil tank. There is no need for handover monitoring and measurement;

The liquid level, temperature, density, volume, and quality of the medium in the trade tank must be monitored and measured frequently, and the accuracy is very high.

Performance comparison of Oil level measurement

Level gaugeLight oilCrude oilHeavy oilAsphaltLiquefied gasOther liquids
Magnetic flap level gaugeokokokpoorNovery good
FloatokokokpoorNovery good
Static pressureGreatGreatokpoorokGreat
Magnetically inducedGreatGreatGreatpoorGreatGreat

Extended reading: Radar Oil Tank Level Sensor

Oil Tank level measurement instruments for different media

Level gaugeLevel measurementTemperature deletionDensity deletionBoundary measurementVolume measurementQuality deletionInstallation situationCost
Magnetic flapHigh precisionCan not be measuredCan not be measuredSmall errorDepends on TDDepends on Tρsimplelow
FloatHigh precisionCan not be measuredCan not be measuredMistaken sheepDepends on TDDepends on Tρsimplelow
radarHigh precisionimportantUnable to deleteUnable toSmall errorDepends on Tρsimplehigh
Hydrostatic pressureBig errorunimportantSmall errorUnable toBig errorDepends on TρcomplexRelatively high
Magnetically inducedHigh precisionimportantUnable to deleteHigh precisionSmall errorDepends on Tρcomplexhigh
UltrasoundHigh precisionunimportantCan not be measuredUnable toSmall errorDepends on Tρcomplexhigh

Explore Oil and Gas Flow Meters

Selecting Guide for Oil level measurement

  1. Oil tank volume
  2. ·Oil tank use
    • High-precision level gauges should be used for trade tanks, and general level gauges can be used for intermediate tanks;
  3. Medium characteristics
    • When storing high-viscosity media (such as heavy oil), try to use a level gauge that does not or has little contact with the measured medium. Such as radar type, ultrasonic type and magneto-induced level gauge, light oil can use general level gauge;
  4. Actual needs of users
    • ·If the user requires high measurement accuracy and low investment restrictions, a level gauge with good performance can be used. Under normal circumstances, the old tank area can be retrofitted or updated according to the use and maintenance of the original level gauge.

Extended reading: The Secret of Ultrasonic Level Measurement

Featured Oil level measurement devices


Measuring and monitoring fluid levels accurately and precisely requires choosing the correct methodology for the target medium and vessel.

Generally, you will choose among six methods for measuring and monitoring fluid levels, each with advantages and disadvantages:

  • Continuous float level transmitters
  • Differential pressure transmitters
  • Load cells
  • Radar level transmitters
  • Radio Frequency (RF capacitive level transmitters)
  • Ultrasonic level transmitter

A tank level sensor is a level sensor used to measure the tank level. The liquid level is the level of the liquid in a sealed container (such as a water tank) or an open container (water tank). The instrument that measures the liquid level is called a liquid level sensor, a liquid level gauge, or a liquid level transmitter. The liquid level sensor is a kind of level instrument. Hydrostatic, Ultrasonic, Magnetostrictive, Radar, Differential Pressure are common choices for tank level measurement. Liquid level sensors have been around for decades for leak detection or level measurement. Commonly measured mediums are Water, Fuel, Diesel, Gasoline, diesel, liquefied gas, liquid ammonia, etc.

Extended reading: Ultrasonic Oil Level Sensor-External Paste-Truck Fuel Tank

Different tank level sensors have different measurement principles. Such as mechanical, radar, ultrasonic, etc.

Extended reading: ultrasonic level sensor for diesel tank

In the petrochemical industry in order for the crude oil process to run continuously and smoothly care has to be taken when storing raw and finished products. Delivery of the crude oil is via pipeline or ship and stored in a large tank until it is ready for final processing.

Accurate level measurement of products of distillation is essential whilst they are being stored in different sized tanks.

In the past, it was expensive as calibratable measuring devices were implemented for level measurement. Nowadays cheaper and low-maintenance measuring systems are used for small and medium-sized tanks. Products are now usually measured by calibratable flow meters while being moved.

Extended Reading: Industrial petrol flow meters Types

Read more about: Capacitive Level Measurement System

Sino-Inst offers over 50 Solutions for Tank Level Sensing. About 50% of these are float liquid level meters, 40% are the level switches.

A wide variety of Solutions for Tank Level Sensing options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of Solutions for Liquid Level Measurement instrumentation, located in China.

Solutions Guide for Liquid Level Measurement

Liquid level measurement and monitoring play an increasingly important role. Liquid level measurement and monitoring directly affect the quality of the production process.

Liquid level measurement is required for process control in many industries. Use liquid level sensors for liquid level measurement. They are divided into two categories: point level measurement and continuous level measurement.

Sino-Inst offers a variety of Solutions for Liquid Level Measurement. If you have any questions, please contact our sales engineers.

8 Types Liquid level measurement methods

  1. Floating ball measurement:

This method is the simplest and oldest detection method, and the price is relatively cheap.

Mainly through the up and down movement of the float to detect the change of the liquid level. It is a mechanical detection, the detection accuracy is easily affected by buoyancy, and the repeat accuracy is poor. Different liquids need to be recalibrated.

It is not suitable for viscous or impurity liquids, which can easily cause blockage of floating balls. At the same time, it does not meet the application requirements of the food hygiene industry.

  1. Tuning fork vibration measurement:

Tuning fork measurement is only a switch output and cannot be used to continuously monitor liquid height. The most representative one is the tuning fork level switch.

The principle is: when the two vibrating forks are filled with liquid or bulk material, the resonance frequency changes, and the switching signal is sent out depending on the detection frequency change.

It can be used to monitor the height of high-viscosity liquids or solid bulk materials, mainly for anti-overflow alarms, low-level alarms, etc. It does not provide analog output. In addition, in most cases it is necessary to install holes on the side of the container.

  1. Ultrasonic measurement:

Since the principle is to calculate the liquid level by detecting the time difference between ultrasonic transmission and reflection, it is susceptible to the energy loss of ultrasonic propagation.

It has the characteristics of easy installation and high flexibility. Usually can be installed in high places for non-contact measurement.
But when used in environments containing steam and powder, the detection distance will be significantly shortened. Therefore, it is not recommended to use it in a wave-absorbing environment with foam.

Read more: Guide: Non-contact Ultrasonic Level Sensing transmitters

  1. TDR (time domain reflection)/guided wave radar/microwave principle measurement:

Its name has many different names in the industry, and it has the advantages of laser measurement. Such as: easy installation, calibration, flexibility, etc.

But it is better than laser detection, such as no need to repeat calibration and multi-function output. Suitable for all kinds of liquid level detection with foam. Not affected by liquid color.

It can even be applied to highly viscous liquids, with relatively little interference from the external environment. But its measuring height is generally less than 6 meters.

Extended reading: Radar Non Contact Water Level Sensor

  1. Laser measurement:

The laser sensor is based on the principle of optical detection and detects light by reflecting light from the surface of the object to the receiver. The light spot is small and concentrated, easy to install, calibrate, and flexible. It can be applied to continuous or limit alarm of bulk material or liquid level.

But it is not suitable for transparent liquids. Transparent liquids easily refract light, causing the light to not be reflected to the receiver. Use in foam or steam environment (cannot penetrate foam or easily interfered by steam), fluctuating liquid (easy to cause malfunction), vibration environment, etc.

  1. Photoelectric refraction measurement:

This detection method emits a light source inside the sensor. The light source is totally reflected by the transparent resin to the sensor receiver.

But when encountering the liquid surface, part of the light will be refracted to the liquid. Therefore, the sensor detects the decrease in the amount of total reflected light to monitor the liquid level. The detection method is cheap and simple to install and debug. But it can only be applied to transparent liquids, and it only outputs switching signals.

  1. Capacitive measurement:

Capacitive measurement mainly measures the height of the material level by detecting the change in capacitance value caused by the change of the liquid level or the height of the bulk material.

There are many types, including capacitive level gauges and capacitive proximity switches that can output analog quantities. Capacitive proximity switches can be installed on the side of the container for non-contact detection.

When choosing, it must be noted that capacitance sensors are easily affected by different container materials and solution properties. For example, plastic containers and hanging materials can easily affect capacitance sensors with analog output.

Read more about: Capacitive Level Measurement System

  1. Static pressure measurement:

This measurement method uses a pressure sensor installed at the bottom. By detecting the bottom liquid pressure, the liquid level is converted and calculated. The bottom liquid pressure reference value is the atmospheric pressure connected to the top or the known pressure.

This measurement method requires the use of a high-precision, flush-type pressure sensor. At the same time, the conversion process requires continuous calibration.

Its advantage is that the detection is not limited by the height of the liquid level. But the higher the height, the higher the accuracy requirements of the sensor. Repeated calibration is required when using for a long time or changing liquid.

Read more about: Hydrostatic level measurement: Measuring Principle

Featured liquid level measurement devices/instruments

Liquid level measurement in a closed tank

Differential Pressure Level transmitter for closed containers

For airtight containers, the inside is isolated from the atmosphere. When the process fluid fills or empties the tank, the pressure in the tank may change from positive pressure to vacuum. This change in tank pressure will directly affect the measured liquid level unless it is compensated for. This can be done by connecting the low-side pipe of the differential pressure transmitter to the top of the tank. Therefore, when measuring the liquid level of a closed tank, a differential pressure transmitter must be used.

Double flanges are used to measure the liquid level of a closed tank.

The calculation method of the differential pressure range: the height of the liquid level to be measured (unit: m) × acceleration of gravity (9.8) × (the density of the measured medium-the density of the capillary filling liquid) (unit: g/cm3) = differential pressure range (unit: KPa).

The selection must know the measurement medium, measuring range, medium temperature, pressure, capillary length, the size and pressure rating of the process connection flange and the flange standard

If you need to measure river water level, open channel level, etc. The Ultrasonic Liquid Level Sensor can be used for non-contact continuous level monitoring.

Portable Ultrasonic Liquid Level Gauge

Portable ultrasonic liquid level indicator is best choice for tanks or pipes level measurement. It is designed to measure the presence or absence of liquid at a certain height position in a tank or in pipelines. Non-contact ultrasonic detection technology.

SI-ML works perfect for detection of dangerous toxic or corrosive liquids. Under ordinary conditions, the maximum wall thickness of measurable containers is 30mm. The product is suitable for the detection of various types of liquids. Liquids are non-crystalline or other particulate matter. For example CO2 Tank. Thanks to non-contact detection technology, this level indicator is ideal for detecting hazardous toxic or corrosive liquids.

Read more about: 7 Level Senors for Tank Level Measurement

Liquid Level Measurement Converter Tools

Converter Tools used to convert and calculate liquid level values or for calculations that require liquid level measurement to obtain other measurement parameters. Help users choose suitable Level sensors and transmitters!

Liquid Level Transmitter 4-20mA Current Output CalculatorLiquid Depth/Level to Hydrostatic Pressure CalculatorPressure to Liquid Level Calculator
Specific Gravity CalculatorHorizontal Cylindrical Storage Tank Contents/Volume CalculatorRectangular Shaped Tank Liquid Volume/Contents Calculator
Vertical Cylindrical Tank Volume/Contents CalculatorDepth/Level Unit ConverterVolume Unit Converter


There are 7 main types of level transmitters that Sino-Instrument offers. Each type of transmitter works in a different way, and makes it useful for different types of processes.

Extended reading: Non Contact Liquid Level Sensor Working Principle

Tank Level Measurement is important for industry storage tank. For example, level measurement of fuel oil tanks and the interface measurement of chemical storage tanks. The liquid level sensor is a kind of level instrument. Hydrostatic, Ultrasonic, Magnetostrictive, Radar, Differential Pressure are commonly choices for tank level measurement. Here, we mainly analyze the magnetostrictive liquid level sensor in the tank applications.

Extended reading: Magnetostrictive Hydraulic Cylinder Position Sensor

Liquid level sensor is a kind of measuring instrument used to measure the change of liquid level in the container. It can display the change of liquid level intuitively and linearly. Among them, the magnetic float level sensor is a kind of one that can display on-site and output analog signals. Kind of level gauge.

There are many types of level gauges. There are intuitive displays such as: glass plate level gauges, glass tube level gauges, etc. There are also magnetic float level gauges, float level gauges, radar level gauges, ultrasonic level gauges, Level gauges with electronic signals such as radio frequency admittance level gauges.

Extended reading: Liquid mass flow controller

Extended Reading: How to Measure Volume of Liquid

Selection of liquid level measuring sensor

The issues that need to be considered before choosing a level measurement sensor include:

  1. Measuring liquid or solid?
  2. What is the temperature and pressure range of the application environment?
  3. Need point level measurement or continuous measurement?
  4. How much liquid level measurement range is required?
  5. Is the tested material conductive?
  6. Will the tested material cover or accumulate on the surface?
  7. Will there be turbulence, foam or steam on the surface of the liquid?
  8. Do you need contact or non-contact level measurement?
  9. What kind of output is needed, analog, relay, digital display or other?

Extended reading: Ultrasonic liquid level sensors

Sino-Inst offers over 10 Solutions for Liquid Level Measurement. About 50% of these are float liquid level meters, 40% is the level switches.

A wide variety of Solutions for Liquid Level Measurement options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of Solutions for Liquid Level Measurement instrumentation, located in China.