Ultrasonic liquid level sensors realize the non-contact continuous detection of liquid level.

Hope you can purchase Ultrasonic liquid level sensors at the best price after reading this Procurement Guide.

Featured Ultrasonic liquid level sensors

You can choose the appropriate Ultrasonic liquid level sensors according to your measurement requirements.

Used to seal tanks and fire tanks. For example CO2 tanks, Halon, FM200, Propane, Novec 1230 and any liquefied gas under pressure.

Used as a non-intrusive tank level gauge. For example Liquid ammonia, liquid chlorine, hydrochloric acid, bromine, chlorethylene, sulfuric acid, freon, and nitirc acid, etc.

Used as an open-hole tank and open liquid level. Such as: fuel tank, open channel liquid level. River level, etc.

Extended reading: Guide to Ultrasonic Level Transmitters

Ultrasonic Level Sensor and Transmitter

The working principle of the ultrasonic level gauge is that the ultrasonic transducer (probe) emits high-frequency pulsed sound waves. When encountering the surface of the measured material (material), it is reflected and folded back, and the reflected echo is received by the transducer and converted into an electrical signal. The propagation time of a sound wave is proportional to the distance from the sound wave to the surface of the object.

The relationship between the sound wave transmission distance S, the sound speed C and the sound transmission time T can be expressed by the formula: S=C×T/2.

Ultrasonic sensors are also ultrasonic transducers, that is, probes.

Ultrasonic sensors are mainly composed of piezoelectric wafers. It can both transmit and receive ultrasonic waves. Low-power ultrasonic probes are mostly used for detection. It has many different structures, which can be divided into straight probe (longitudinal wave), oblique probe (transverse wave), surface wave probe (surface wave), Lamb wave probe (Lamb wave), dual probe (one probe reflection, one probe reception) Wait.

Ultrasonic transmitter refers to an instrument that can convert liquid level detection signals into analog signals or other signals. For example, we can require the ultrasonic level transmitter to output a 4-20mA signal.

Extended reading: GWR Corrosive Liquid Chemical Level Sensor

Ultrasonic Level Sensor 4-20mA

4-20mA is the common output signal of ultrasonic level gauge. To be precise, it can be divided into 2-wire, 3-wire, and 4-wire.

Two-wire system: The two-wire ultrasonic level meter shares a loop for power supply (DC24V only) and signal output (DC4-20mA). Only two wires are used and it is the standard transmitter form. The downside is that the transmit power is weak. Not suitable for liquid level measurement with large fluctuations. When the liquid level has a large volatilization. Measurements are also not ideal.

Three-wire system: The three-wire ultrasonic level gauge is actually a four-wire system. Its power supply (only DC24V) is separated from the signal output (DC4-20mA) loop. Use two lines each. When their negative terminals are connected in common, three wires are usually sufficient. The advantage is that the transmit power is larger. Suitable for liquid level and material level measurement in a variety of conditions. The effect is better.

Four-wire system: The power supply (DC24V or AC220V) is separated from the signal output (DC4-20mA) loop. The advantage of using two wires each is that the transmit power is greater. At the same time, it provides high and low relay output, adding new functions.

Extended reading: Non-Contact Level Measurement

Ultrasonic Level Sensor for Solids

In theory, ultrasonic liquid level sensors can be used to detect solid material levels. However, the general range should be reduced. The particles are uniform and the thickness is moderate. For example, corn, sand, detection is still very good. But the range is almost halved. If the particles are too fine, such as flour, cement powder will not work well.

Some ultrasonic level gauges can detect solids and liquids. For example, VEGA’s ultrasonic level meter does not distinguish between solid and liquid models.

And some brands of ultrasonic level gauges can only measure liquids, such as Siemens ultrasonic level gauges. It distinguishes the models that measure liquids and the models that measure solids. There are also models that can measure solid liquids.

Extended reading: Magnetostrictive Level Transmitter Advantages And Disadvantages

Laser level transmitter for solids

Non Invasive Level Measurement

Non Invasive Level Measurement means that the liquid level sensor is attached to the outside of the tank to detect the liquid level. In this way, there is no need to perforate the tank. Installation and monitoring are very convenient.

At present, the most commonly used Non Invasive Level Measurement is the ultrasonic sensor.

Non Intrusive Level Gauge

In addition to the Non Intrusive Level sensors at the top of this article. We also have a Non Intrusive Level Gauge. This externally mounted ultrasonic level sensor is mostly used for truck fuel tank level monitoring. Of course, it can also be used for other tank level monitoring according to the parameters.

Ultrasonic oil level sensor uses the principle of ultrasonic detection to detect the fuel level of the fuel tank. The fuel volume data is transmitted to the background monitoring system to achieve real-time monitoring of vehicle fuel consumption. Ultrasonic oil level sensor is mainly used in the field of Internet of Vehicles to monitor the change of fuel level in the fuel tank in real-time to achieve fuel level detection. It can be used to prevent fuel stealing, optimize operating costs, optimize driver driving behavior, and assist statistical decision-making. At the same time, this product can also be used in chemical, water conservancy, storage tanks, and other fields that require level detection.

Read more about Application 2: Tank Level Monitoring In The Oil And Gas Industry.

More Non Contact Liquid Level Sensors

Related Blogs

Sino-Inst offers over 10 Ultrasonic liquid Level Sensing sensors and transmitters for level measurement. About 50% of these are float liquid level meters, 40% is the level switches.

A wide variety of Ultrasonic Level Sensing sensors and transmitters options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of Ultrasonic Level Sensing sensors and transmitters instrumentation, located in China.

Liquid Level Gauge also called Liquid level indicator. Liquid Level Gauge has contact and non-contact type. Here mainly discusses the non-contact Liquid Level Gauge, which is used for CO2 cylinder level measurement.

Portable Liquid Level Gauge Features

• No contact with medium
• Suitable for toxic, corrosive, or invasive medium
• No need for drilling or welding on the container wall
• Advanced ultrasonic sensor technology
• Reliable measurement results
• Easy and convenient to operate and maintain
• Ultrasonic adaptive detection algorithm
• High-contrast OLED color display, suitable for outdoor use under strong light
• The added ultrasonic-waveform-display function facilitates parameter testing, waveform comparing and application of other functions to ensure measurement accuracy in complicated situations
• Gooduser interface design
• Comprehensive software displaysmeasurement resulting a simple manner

PLI range of Liquid Level Gauges

British CLASS PLI range of liquid level gauges testing equipment:

The portable liquid level meter is used in the detection of gas in the liquid state in the fire extinguishing system. It mainly detects: CO2\FM200\Halon (halogen fire extinguishing agent and other substitutes).

The instrument can indicate the position of many gases in the cylinder when they are in the liquid state, including propane or other gases. It can also be used to indicate the oil level and water level in the container, etc. The working principle of the instrument is a different response of an ultrasonic pulse to liquid with and without the state.

The portable liquid level meter uses ultrasonic signals to penetrate the wall of the steel cylinder and then enter the liquid gas.

The instrument reflects how much echo it receives through the pointer of the instrument itself.

The deviation value reflected by the instrument allows us to clearly identify the position of the gas and liquid interface. In this way, a reliable liquid level position can be obtained.

💡 Industrial Propane Tank Level Indicators for Industrial Tank Level Measurement

Further reading: Industrial LPG/Propane flow meter

ML 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.

Extended Reading: Laser level transmitter for water

ML Portable Ultrasonic Liquid Level Gauge Specifications

Measurement accuracy	<2mm
Tank wall thickness	3-30mm
Measurable tank material	Steel, stainless steel, glass, unformed plastics
Measurable medium	Pure liquid, milky liquid, suspension liquid
Ambient temperature	-20℃~60℃ (-4℉~+140℉)
Ambient humidity	15%-85%RH
Power supply	Two 18650 lithium batteries
Current	150mAh (on average)

Read more about: External Ultrasonic Tank Level Sensor Working Principle

PLI PLUS vs ML Portable Liquid Level Gauges

Compare the two:

1. Different accuracy:
   PLI PLUS Accuracy: ±1.5mm
   ML Accuracy: <2mm
2. Different prices
   ML Portable Liquid Level Gauge. Made in China. Sino-Inst can provide users with the best prices. Save costs.

Please contact Sino-Inst sales engineer to apply for sales discount.

Extended reading: GWR Corrosive Liquid Chemical Level Sensor

Portable ultrasonic liquid level gauge for co2

Co2 cylinder specifications (external diameter division):

The CO2 cylinders measured by this meter are divided into the following 4 specifications: 215mm-225mm diameter cylinders. 270mm-280mm diameter cylinders. 345mm-355mm diameter cylinders. 395mm-405mm diameter cylinders. There are no excessive requirements for the height of the medium and the tank.

Co2 cylinder measurement operation:

1. Select “co2 cylinder”-“Choose a suitable cylinder diameter” through the menu and enter the measurement interface.
2. Hold the probe vertically and tightly on the tank, and press the <Measure> button to measure.
3. Measurement results are based on measurement parameters and level indicator lights (red is “no liquid”, green is “with liquid”)
4. Generally, the measurement is started from the bottom of the storage tank (measurement with liquid position). If the measurement parameter is> = 2, the current level is considered to be a liquid-free position. And <2 is considered to be a liquid level. if it is floating around 2, It is considered that the liquid level of the horizontal plane is approaching the liquid surface (usually about 5 cm).
5. Take multiple points on the same horizontal plane for measurement. And take the result with the highest probability as the final result (avoid the interference of welds and unknown factors).
6. Find the liquid level position step by step through the approximation measurement.

Co2 cylinder measurement Note:

Due to the irregular shape of the air outlet and the many welding kits on the top of the carbon dioxide cylinder, the bottom and top measurement results are invalid. (If the fuel tank is full, the top is usually empty).

Extended reading: Magnetostrictive Hydraulic Cylinder Position Sensor

More Featured Non-Contact Liquid Level Gauges

Sino-Inst offers over 20 Liquid Level Gauges and transmitters for level measurement. About 50% of these are ultrasonic liquid level meters, 40% is the level switches.

A wide variety of Liquid Level Gauges and transmitters options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of Liquid Level Gauges and transmitters instrumentation, located in China.

Monitoring the level of liquid chlorine storage tanks is a common problem in the chlor-alkali industry.

This article combines the application and comparison of the actual use of the liquid chlorine storage tank level measurement level gauge, which has practical guiding significance for the selection of the liquid chlorine storage tank level gauge in the chlor-alkali industry under the existing technical conditions.

Liquid Chlorine Storage Tanks chemical properties

Liquid chlorine is a yellow-green liquid. Boiling point -34.6℃. Melting point -103℃. It is vaporized into gas under normal pressure. Inhalation of the human body can be severely toxic, severely irritating and corrosive. It burns and explodes when mixed with other flammable gases in sunlight. Chlorine is a very reactive element and can react with most elements (or compounds).

Liquid chlorine is the basic chemical raw material, which can be used in metallurgy, textile, papermaking and other industries, and is the raw material for the synthesis of hydrochloric acid, polyvinyl chloride, plastics, and pesticides. Packed in high-pressure steel cylinders.

Hazard characteristics: Liquid chlorine will not burn, but it can support combustion. Generally combustible materials can be burned in chlorine gas, and general flammable gas or steam can also form explosive mixtures with chlorine gas.

Chlorine gas can react violently with many chemicals such as acetylene, turpentine, ether, ammonia, fuel gas, hydrocarbons, hydrogen, metal powder, etc. to explode or generate explosive substances. It is almost corrosive to metals and non-metals.

Liquid chlorine is generally used after gasification and has a wide range of uses. It is a strong oxidant. It is used for bleaching in the textile and paper industry, purification and disinfection of tap water, refining of magnesium and other metals, and production of pesticides, detergents, plastics, rubber, Various chlorine compounds such as medicine.

Liquid chlorine is a highly toxic substance, and the emergency code number is 31001. Should be stored in a cool, ventilated warehouse, special warehouse for special storage. Do not co-store or carpool transportation with combustibles, explosives and ammonia.

Level gauges types used for tank level measurement

In the tank level measurement, the following types of level gauges have a large number of practical applications:

1.Buoyancy level gauge

Such as float level gauge, flap level gauge, float level gauge, floating plate level gauge, float level gauge, steel belt level gauge. This type of buoyancy level gauge has measurement accuracy. However, the on-site installation and structure are more complicated, there are many mechanical parts, and the daily maintenance amount is very large in the actual application process.

2.Pressure type level gauge

Pressure transmitters, single-flange level transmitters, and drop-in level transmitters are often used for liquid level measurement in open vessels. Differential pressure transmitters and remote double-flange differential pressure transmitters are often used for liquid level measurement in closed vessels. Differential pressure level gauges are easily affected by medium density and temperature changes during measurement, and the maintenance of accessories is large. If the liquid level of a strong corrosive medium is measured, the instrument is expensive.

Extended reading: Hydrostatic Level Measurement

3.Microwave level meter

Ultrasonic level gauges, radar level gauges, and guided wave radar level gauges are all microwave level measuring instruments that can be used for solid and liquid level measurement. Although these level gauges have advanced technology and improved measurement accuracy, they are suitable for pressure vessels that store light hydrocarbons, liquid ammonia, and liquid chlorine.

Due to the low dielectric constant of the gas phase medium, volatility and a large number of droplets, it will absorb and affect the reflection of electromagnetic waves. Interference to the level measurement of the microwave level meter, resulting in unstable measurement value of the level meter.

Extended reading: What is the difference between ultrasonic and radar level transmitters?

Featured Level meters

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.

Application of different level gauges in Liquid Chlorine Storage Tanks

Practice is the only criterion for testing truth. Each level gauge has its advantages and disadvantages, and the application performance of different level gauges under the same working conditions is not the same.

In this article, Sino-Inst shares with you the application experience of different types of level gauges in the level measurement of liquid chlorine storage tanks in the plant.

1.Application of radioactive level gauge in Liquid Chlorine Storage Tanks

The cobalt 60 radioactive level gauge is used to perform high-limit measurement and alarm on the liquid level of the liquid chlorine storage tank.
The specific application is: installing cobalt 60 radiation sources and receiving devices on both sides of the high point of the liquid chlorine storage tank.

The radioactive level gauge produces different amounts of radiation when the storage tank is full or dissatisfied. The meter judges whether the liquid level of the storage tank exceeds the limit according to the change of the radiation amount and sends out the corresponding switch alarm signal.

The cobalt 60 radioactive level gauge is installed on the outside of the storage tank and does not come into contact with the liquid chlorine. There is no potential for chlorine leakage, and the position measurement is accurate and reliable. However, the radioactive level gauge cannot realize continuous measurement and monitoring of the liquid level and the cobalt 60 radioactive source is easy to check Instrument maintenance workers cause personal hazards and are therefore not suitable for production.

2.Application of top-mounted float level gauge in Liquid Chlorine Storage Tanks

The top-mounted float level gauge is used to measure the liquid level of the liquid chlorine storage tank. The top-mounted float level gauge is inserted into the liquid chlorine storage tank from the top.

When the liquid level in the liquid chlorine storage tank changes, the float floats up and down along the measuring tube with the change of the liquid level. The magnetic steel in the anti-corrosion float continuously attracts the reed switch relays in different positions. The liquid level is shown by the indicator position.

The top-mounted float level gauge works well in the initial stage of use. But with the passage of time, its drawbacks have gradually emerged. The top-mounted float level gauge needs to be in contact with liquid fluorine when measuring, and it is prone to fluorine gas leakage. Site environment It is highly corrosive, and the measuring rod of the reed switch relay is often desoldered due to corrosion. The failure rate is very high and the maintenance workload is large, which affects normal production.

The acid mud contained in the liquid chlorine adheres to the floating ball steel pipe. It causes the floating ball to move and even gets stuck, causing the level gauge float to not follow the liquid level change normally. A false liquid level is generated and the process production operation is affected. It is not fully applicable to liquid chlorine storage tank level measurement.

3.Application of capacitive level gauge in Liquid Chlorine Storage Tanks

Use a capacitive level meter to measure the level of the liquid chlorine storage tank. The capacitive level gauge is inserted from the top of the liquid chlorine storage tank, and the capacitance of the level gauge changes in proportion to the change height of the liquid chlorine level in the storage tank. This principle is used to achieve continuous measurement of the liquid chlorine storage tank level.

Capacitance level meter can meet the continuous measurement of liquid chlorine storage tank level, but it has the following disadvantages:

The measuring electrode of the capacitance level meter needs to be inserted into the liquid chlorine storage tank, and chlorine leakage is likely to occur during installation or disassembly, which endangers personal safety.

After the capacitance level gauge has been working for a period of time, the acid mud contained in the liquid chlorine will adhere to the inner and outer electrodes of the capacitance level gauge, causing changes in capacitance and large errors in measurement.

Due to the high toxicity of chlorine gas, the malfunctioning meter cannot be disassembled and repaired at any time, causing the malfunction meter to be unable to be repaired for a long time.

Due to the above reasons, the capacitance level meter is gradually eliminated after a period of use.

4.Application of side-mounted magnetic flap level gauge in liquid chlorine storage tanks

The side-mounted magnetic flap level gauge is connected to the storage tank with a measuring tube. The measuring tube is equipped with a magnetic float. The outside of the tube is composed of two-color porcelain rollers side by side to form an indicator. The magnetic float moves up and down with the change of the liquid chlorine level, driving the magnetic roller Rotate. The magnetic roller therefore changes color to indicate the liquid level.

The side-mounted magnetic flap level gauge has a good effect in the initial stage of use. Because the indicator is completely isolated from the medium, the effect of corrosion is overcome.

The magnetic float is sealed in the measuring tube to eliminate the hidden danger of chlorine leakage and ensure safety.

The side-mounted magnetic flap level gauge is accurate and reliable in measurement and indication, with very low failure rate and little impact on production.

The disadvantage is that the measuring tube wall is frozen, and the acid sludge contained in the liquid chlorine will also cause the magnetic float to freeze or jam when working for a long time. This will cause measurement errors. It will seriously affect the process and production operations. Therefore, the liquid chlorine storage tank level cannot be fully applied measuring.

5.The application of external level gauge in Liquid Chlorine Storage Tanks

A. Working principle of external level gauge

The external measuring level gauge is an intelligent field transmitter type instrument. The external measuring level gauge flameproof host is installed near the liquid chlorine storage tank. The measuring head of the external measuring level gauge is tightly attached to the outer wall of the container. It depends on the detection container wall The tiny mechanical vibration on the upper side becomes an electric signal and is transmitted to the external measuring level gauge flameproof host. After this signal is processed, it becomes a digital signal and is sent to the CPU.

The instrument host filters and recognizes the various vibration waves of different modes obtained by the measuring head, and removes signals that have nothing to do with the change of the liquid level. It uses special software to perform complex calculations on the waveform of the signal, and uses artificial intelligence algorithms to calculate it. Analysis. To calculate the liquid level.

B. Advantages of external level gauge

The external level gauge has the following advantages:

①It can be used in the most demanding environment. It can measure liquids under any pressure. It can measure the most toxic liquids. It can measure the most corrosive liquids. It can measure absolutely sterile or extremely pure liquids.

②Safe to use. When measuring toxic, corrosive, pressure, flammable, explosive, volatile, and easy to leak liquids. Because the measuring head and the instrument are outside the container. During installation, repair, and maintenance operations, the operator does not touch the tank The liquid and gas inside are very safe. Even if the instrument is damaged or repaired, there will never be leakage.

③Meet environmental protection requirements. Neither liquid nor gas leaks. It does not pollute the environment and is a green instrument.

④ Installation and maintenance are the most convenient and economical. Because the liquid level gauge does not need to open a hole in the container, does not need a flange, or a connecting pipe, it is very convenient to install and maintain. The external level measuring instrument does not require manual calibration during installation and use, which is very convenient.

⑤High reliability and long service life. Because there are no mechanical moving parts in the measuring head of the liquid level meter and the meter, it is strictly sealed and isolated from the outside world. It will not produce abrasion or corrosion, it is very durable and reliable, and the maintenance workload is very small.

⑥ Accurate measurement. The external level measuring instrument can be continuously and automatically calibrated to ensure the highest measurement accuracy. In addition, the external level measuring instrument is divided into temperature compensation type, its measurement accuracy reaches 1%. Self-calibration type, its measurement accuracy reaches 0.2%. Among them, the self-calibrating liquid level gauge does not need manual calibration.

C. Disadvantages of external measuring liquid level gauge

① There are still some shortcomings of the external measurement type level gauge. The meter itself has a measurement dead zone. The external measurement type level gauge can only display a low level alarm within 200mm of the bottom of the container and cannot indicate an accurate level value. Since the company’s liquid chlorine storage tank level measurement monitoring is mainly to ensure high-level accurate monitoring, this defect does not affect normal use.

After analysis and comparison, it is believed that from the perspective of safe production and maintenance work, the external measurement type level gauge is currently the most suitable instrument for liquid chlorine storage tank level measurement.

②The advantage of the external measurement type level gauge is that it is easy to install, and there will be no hidden dangers of chlorine leakage and corrosion of the instrument.

According to reports from other petrochemical plants: the external measurement type level gauge will also have measurement failures after a period of time, mainly due to changes in the paste medium and gap, which is a common problem. This is also a problem that the tuning fork limit switch can avoid.

Therefore, the biggest obstacle to the application of external ultrasonic level meters is the need to achieve long-term all-weather operation after installation, which is a technical problem.
In addition, for instruments that have problems on site, the supplier must respond to and solve the problems in a timely manner. This is a service problem.

Featured external level gauges in Liquid Chlorine Storage Tanks

HS-2000 External Mounted Ultrasonic Tank Level Sensor- (referred to as “external level gauge”). It adopts advanced signal processing technology and high-speed signal processing chip. It breaks through the influence of container wall thickness. Realizes the height of the liquid level in the closed container True non-contact measurement.

The ultrasonic liquid level sensor (probe) is installed directly under the outer wall (bottom) of the container under test. Calibrate the outer wall of the probe. There is no need to open holes for the container to be tested, easy to install, and does not affect production. It can accurately measure the level of various toxic substances, strong acids, strong alkalis and various pure liquids in high-pressure airtight containers.

The HS-2000 External Mounted Ultrasonic Tank Level Sensor has no special requirements for the material of the liquid medium and the container. The explosion-proof design is adopted to meet the explosion-proof requirements.

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Sino-Inst offers over 20 Liquid Level gauges for level measurement. About 50% of these are fuel level meters, 40% is the tank level sensor.

A wide variety of Liquid Level gauges for level measurement options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of Ultrasonic Tank Level measurement instrumentation, located in China.

Magnetostrictive level gauge application tutorial. Just one article to help you understand !

Magnetostrictive level gauge measurement principle

Substances expand and contract with heat. In addition to heating, magnetic and electric fields can also cause the size of objects to elongate or shrink. Under the action of an external magnetic field, the size of a ferromagnetic substance elongates (or shortens). After the external magnetic field is removed, it returns to its original length. This phenomenon is called magnetostriction (or effect).

Based on the principle of magnetostriction, a magnetostrictive wire is installed in the non-magnetic probe, and the sensor is connected to one end of the magnetostrictive wire. The main control electronic unit sends a narrow electromagnetic pulse to the magnetostrictive line, and the electromagnetic pulse is conducted along the magnetostrictive line.

When the magnetic field generated by the pulse interacts with the magnetic field generated by the magnet in the float marking the liquid level/interface, a torsional stress wave will be generated on the magnetostrictive line, which will return to the sensor along the magnetostrictive line. Convert the captured return wave into an electronic pulse signal and send it back to the main control electronic unit.

The main control electronic unit accurately measures the time interval between the emission pulse and the return pulse through a precision circuit, and calculates the position of the float, that is, the height of the liquid level/interface.

Magnetostrictive level gauge application range

◆Power plant: reservoir, waste gas purification tank, fuel tank, etc.
◆Oil field: crude oil or product oil storage tank, three-phase separator, settling tank, sewage tank (pool), etc.
◆Petrochemical: oil pipelines, distillation towers, concentration tanks, liquefied gas tanks, ammonia tanks, oil refineries, etc.
◆Chemical industry: distillation tower, ammonia tank, toxic liquid tank, etc.
◆Water and water treatment: reservoirs, sewage tanks, water treatment tanks, sedimentation tanks, digestion towers, etc.
◆Others: food, pharmaceutical, environmental protection, papermaking and other industries

Read more about: Common Types Of Heating Oil Tank Level Sensors

Features of magnetostrictive level gauge

◆Multi-function: can measure liquid level and interface position separately or at the same time
◆High precision: measurement accuracy ±0.8mm or 0.01%FS (the larger one)
◆Wide scope of application: flexible and diversified installation methods.
◆Output mode: on-site instructions and remote electrical signal output
◆Low power consumption: two-wire loop 4-20mA output, LCD display

The principle and characteristics of the magnetostrictive level gauge are briefly introduced above.

The following content of this article will give a detailed introduction to the application of magnetostrictive level gauges. I hope you have a deep understanding of the installation and use of magnetostrictive level gauges on site after reading this article.

1.Probe form of magnetostrictive level gauge

Magnetostrictive level gauges usually have rod probes and cable probes. With different floats, the liquid level or interface can be measured.

①The probe is a rod type probe, which can measure liquid level or interface with different floats. The maximum length is 4m.

②The probe is a rod probe, which can be equipped with double floats to measure the liquid level and interface at the same time. The maximum length is 4m.

③The probe is a cable probe, which can measure liquid level or interface with different floats. The maximum length is 20m.

2.Installation method and structure of magnetostrictive level gauge

The magnetostrictive level gauge can be combined with the outer pontoon or the outer pontoon + magnetic flap into several installation methods. It is not only easy to install and maintain, but also can cooperate with the on-site flip display. Realize the on-site and remote dual output. The probe has multiple parameters to choose from. Including: installation type, connection method, probe installation type, end structure, etc.

①Installation of probe rod and magnetic flap

◆For the probe structure that is attached outside the probe. The probe rod is usually fixed on the opposite side of the connecting structure, as shown in the figure below.

◆When a magnetic flap is needed, the magnetic flap is usually fixed on the opposite side of the connection structure. At this time, the probe rod will move to any position on the left and right sides of the float, as shown in the figure below.

② Magnetostrictive level gauge probe top insertion + side/side installation method

The picture above shows the most commonly used side mounting: side-to-side mounting (the probe mounting type is for inserting the top of the probe)

Figure a. Connection mode: flange connection, bottom structure: end cover + plug
Figure b. Connection method: chuck connection, bottom structure: blind flange
Figure c. Connection method: welding, bottom structure: short pipe + drain valve
Note: There is no necessary correspondence between the connection mode and the end structure.

③The bottom of the magnetostrictive level gauge probe is inserted + side/side installation method

The probe installation types in the above figure are all “insert installation at the bottom of the probe”.

Figure d. Top structure: end cover + plug
Figure e. Top structure: blind flange
Figure f. Top structure: closed
This structure is not conducive to sewage and maintenance. Therefore, when using the probe upside down, it is recommended to install the probe upside down and externally bound.

④Figure g shows the magnetostrictive level gauge probe top insertion + top/side installation
⑤Figure h shows the bottom insertion + side/bottom installation of the magnetostrictive level gauge probe
⑥Figure i shows the magnetostrictive level gauge probe top insertion + top-mounted installation + magnetic flap display
⑦Picture j is the magnetostrictive level gauge probe top insertion + side/side installation + magnetic flap display
Note: The two installation methods of ⑥ and ⑦ are suitable for occasions where the measurement position is low.

⑧Figure k Magnetostrictive level gauge probe upside-down external binding + bottom-mounted plug-in installation + magnetic flap display
⑨Figure l Magnetostrictive level gauge probe upside-down external binding + side/side installation + magnetic flap display

Note: ⑧ and ⑨ installation methods The probe installation type is the probe inverted and externally bound. These two installation methods are suitable for occasions with higher measuring positions. The end cover + plug structure or blind flange structure is selected for the bottom, which is conducive to sewage and maintenance.

The above pictures are all attached to the outside of the probe.
⑩Figure m shows the probe front-mounted external binding installation
⑪Figure n shows the probe front-mounted external binding installation
⑫Figure o shows the probe upside-down and external binding installation
The manufacturer will choose the formal installation type according to the top structure

The picture above is a schematic diagram showing the magnetostrictive level gauge with a magnetic flap.
⑬Picture p is side-mounted, side-to-side mounted, with the probe top inserted
⑭Figure q shows two views of side-mounted, side-to-side installation, the probe top is inserted and installed, and the bottom end cover + plug structure
⑮Figure r is a schematic diagram of the side-mounted, side-to-side mounted, the probe is mounted with an external binding type, the top is closed, and the bottom drain valve structure is schematic.

Typical tank application of magnetostrictive level gauge

1.Magnetostrictive liquid level gauge is used for liquid level measurement of agitated and foamed containers

When applied to occasions with stirring and foam, liquid level fluctuations and foam will affect the measurement. At this time, it is recommended to use a top-mounted probe or add a protective tube to the probe.

2.Magnetostrictive level gauge is used for liquid level measurement of small-sized containers

◆When the container to be measured is small, the use of side-to-side connection will reduce the effective measurement range. At this time, the side-to-bottom or top-to-side connection can be used to effectively increase the measurement range.

◆When the process temperature is high, you should pay attention to heat preservation, as shown in the figure on the right, you can use insulation cotton for heat preservation, or use electric heat tracing and steam heat tracing for heat preservation.

3.Magnetostrictive liquid level gauge is used for liquid level measurement of buried tank

The “buried tank” here includes a container whose main body is buried in the ground and a container whose sides are covered and cannot be installed with meters. For the measurement of this type of container, simple applications can use rod probes and cable probes. If you need on-site display, you need to use a magnetic flap + top-mounted plug-in installation type

4.Magnetostrictive liquid level gauge is used for liquid level measurement of ceiling tanks and suspended tanks

When the location of the container to be measured is high, it is difficult to install, debug, and maintain the instrument, and it is difficult to display on-site. It is recommended to use magnetic flap + bottom-mounted plug-in installation type. Or magnetic flap + bottom-mounted side-side mounting type.

Magnetostrictive level gauge installation methods and professional knowledge of typical applications are shared here.

I don’t know if you have noticed: whether there is a sudden sense of clarity when selecting the magnetostrictive level gauge based on the on-site working conditions and these installation and application examples. The selection is simply to convert the legend to the response model!

Magnetostrictive Level Gauge/Sensors for Sale

Sino-Inst offers over 10 Magnetostrictive level gauges for level measurement. About 50% of these are Magnetostrictive liquid level meters, 40% is the tank level sensor.

A wide variety of Magnetostrictive level gauges options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of Magnetostrictive level measurement instrumentation, located in China.

1. Introduction

In order to grasp the operation information of the storage tank in real time and accurately. For example the level, density, pressure, temperature, volume, and quality of the storage medium in the storage tank. To ensure the safety of the storage tank, many oil storage tanks have been studied at home and abroad. Detection and measurement methods and devices. Such as static pressure method, liquid level meter, hybrid method, etc., designed to a variety of measurement technologies, such as pressure type, servo type, radar type, magnetostrictive type, float steel belt type, etc.

Due to many factors such as technology, economy, and use. The monitoring, measurement, and safety management of oil storage tanks in our oil depots mainly rely on manual rulers, manual measurements, and manual inspections. Its measurement accuracy, reliability, maintainability, and real-time performance are difficult to meet the development needs of oil depot informatization construction.

An oil tank level gauge based on magnetostrictive measurement technology has a simple structure and high measurement accuracy. It can measure liquid level, boundary level, multi-point temperature, and other advantages at the same time.

This year, it has been applied more and more in the monitoring and measurement of oil storage depots, such as Sinochem Nantong Oil Depot. Therefore, the magnetostrictive level gauge is applied to the information system of the product oil storage tank oil depot. Real-time monitoring and metering management of refined oil storage tanks. Not only can real-time collection, storage, and management of oil depot receiving, sending, and storing information. It can also reduce staff to increase efficiency and improve oil depot management.

2. Working principle of the magnetostrictive level gauge

2.1 The composition of the magnetostrictive level gauge

The magnetostrictive level gauge is mainly composed of a float (with a magnetic ring inside), a transmitter (or an electronic warehouse is composed of a pulse generator and a receiver), a waveguide equipped with a magnetostrictive wire and a temperature detector. . The transmitter (electronic warehouse) is equipped with a magnetostrictive wire waveguide and temperature detector are integrated structure. The transmitter and temperature detector adopt a modular and integrated design.

2.2 Working process of the magnetostrictive level gauge

The working principle of the magnetostrictive level gauge is mainly to use the combination of magnetic effect and super-generating effect to achieve the purpose of measurement. Magnetic effect and Weidmann effect and Villari effect.

When the transmitter is powered on, the pulse generator and receiver start to work. The pulse generator in the electronic head of the level gauge first applies an electrical pulse signal to the magnetostrictive waveguide wire. This electrical pulse is accompanied by a circular magnetic field. When the magnetic field encounters the longitudinal magnetic field generated by the magnet in the float at the speed of light. It will be vectorially superimposed to form a spiral magnetic field.

According to the Weidmann effect, when the magnetic field of the magnetostrictive material changes. The weak size of the magnetostrictive material itself will also change accordingly. Therefore, when the synthetic magnetic field changes to form a spiral magnetic field, the magnetostrictive waveguide wire will be twisted and deformed. This excites the torsional wave (or return pulse).

The torsion wave will be transmitted back to the induction coil in the sensor head in the form of ultrasonic waves along the waveguide wire and will change. When the coil in the sensor, it will be converted into transverse stress.

According to the Villari effect, when a magnetostrictive material is physically deformed. Will cause changes in the magnetic field strength in the magnetostrictive material. Therefore, the magnetic flux passing through the sensor coil will change, and an induced electromotive force that can be detected will be generated at both ends of the sensor coil. The propagation speed of the supergenerated torsion wave is only related to the elastic modulus and density of the magnetostrictive waveguide filament, which is a constant.

Therefore, the time difference from the moment the current pulse is emitted to the detection of the induced electromotive force is multiplied by this fixed velocity V. The position of the magnet (float) can be accurately calculated. Its liquid level height L=V*(t1-t2).

Extended reading: Fuel-Diesel-Water Tank Level Sensor Monitoring

2.3 Technical characteristics of the magnetostrictive level gauge

The petrochemical industry has gradually paid attention to the monitoring of oil levels. According to the working principle, it can be roughly divided into the following types:

• Mechanical float level gauge. The price is low, but its accuracy is low, and it cannot meet the requirements for use as a measuring instrument. And the failure rate is high, and the steel belt is prone to jam.
• Capacitive liquid level gauge. The price is moderate and the measurement accuracy is acceptable. However, due to its large temperature drift, its stability is insufficient, the accumulated error is large, and the measured value is not accurate.
• Light guide type liquid level gauge. The price is moderate, but the measurement accuracy is low and the stability is poor.
• Radar level gauge. The price is expensive, the liquid level accuracy, reliability, and stability are all ideal, the installation is also very convenient, and different media are practical.
• Magnetostrictive liquid level gauge. The price is more expensive, the stability is better, and it is easy to install. But it cannot be used in heavy oil with high viscosity and high density. Of course, the magnetostrictive level gauge has many other outstanding advantages. Specifically in:

① The work is very reliable. Because the second son telescopic level gauge uses the waveguide principle to work. Therefore, there are no mechanical moving parts inside the device, and there are no defects such as wear. The entire converter is enclosed in a stainless steel tube. No contact with the measured medium. Therefore, the sensor works reliably and has a long life span.

②Multi-parameter measurement. Another major feature of the magnetostrictive level gauge is that it integrates measurement of liquid level, water interface, temperature and other parameters. Because the electronic components in the magnetostrictive level gauge can detect the continuous magnetic waves generated by the same emission pulse. Therefore, two or more magnetic floats can be installed on the same sensor. Just ensure that the weight of the float corresponds to the specific gravity of the medium. The liquid level and interface can be measured at the same time, realizing multi-parameter measurement.

③High measurement accuracy. Because the magnetostrictive level gauge uses waveguide pulses to achieve measurement. During work, the displacement of the measured liquid surface is measured by the time difference between the excitation pulse and the induction pulse. Therefore, the accuracy is extremely high, which is a measurement accuracy that is difficult to achieve with other sensors. At roughly the same or lower cost, magnetostrictive level gauges have higher accuracy and better economic benefits than other measuring systems that use capacitance, pressure, mechanical, ultrasonic or servo devices.

④ Good safety performance. The explosion-proof grades of magnetostrictive level gauges are generally flameproof and intrinsically safe. Suitable for working in various flammable, explosive, high temperature, high pressure and other dangerous places. No need to manually open the filling cap during measurement. Avoid the hidden danger of insecurity caused by manual measurement.

⑤ Easy to install and maintain. Since the magnetostrictive level gauge adopts flange connection, the installation is extremely simple. Moreover, the core components are not in contact with the medium, and the product has a modular structure. Intelligent design, no need for regular maintenance and regular calibration, which brings great convenience to users.

⑥Easy to realize networking. The output of the magnetostrictive level gauge is a standard signal. It is convenient for crisis management and can better cooperate with computer. It is also easy to make long-distance transportation possible.

Of course, the change of medium density will have a certain impact on the accuracy of the magnetostrictive level gauge. But it can be installed by installing a suitable float. Reduce the immersion of the float, reduce the outer diameter of the float, and overcome and avoid it to the greatest extent through temperature compensation. After on-site testing, the magnetostrictive level gauge is the same as the radar level gauge, with blind spots and inaccurate measurement of tank bottom oil.

Extended reading: Radar Oil Tank Level Sensor

3. Application of magnetostrictive level gauge in Sinochem Zhuhai Phase II product oil tank

At present, Sinochem Zhuhai Phase II Chenpin Oil Depot with a total of 412,000 m3 has been completed. Among them, the online liquid level monitoring system involving 12 light product oil tanks totaling 192,000 m3 uses magnetostrictive level gauges. The liquid level system consists of a magnetostrictive liquid level gauge, H-500 field display, H-1000 (oil depot) 10.4 inch color touch screen controller and YSMK-YK oil depot information monitoring and management system.

This system can display liquid level, interface height and temperature with H-500 on-site display in the field. In the control room, the H-1000 (oil depot) controller is used to display data in real-time with three-dimensional graphics and digital methods. Use sound and light alarm to prevent oil spill and oil shortage. Therefore, the detailed functions of the system are as follows:

• Accurate real-time measurement of oil level, water level and temperature. Using 10.4 color LCD screen, the number of storage accuracy points is not limited. It can be customized according to the customer’s volume meter, and the oil height, water height, temperature, volume, and remaining volume can be displayed in graphical and digital ways.
• Alarm function. The system has multiple alarm functions such as high liquid level (pre) alarm, low liquid level (pre) alarm, and high water level alarm. Use sound and light alarm to prevent oil spill and oil shortage.
• Self-diagnosis, management and equipment failure alarm.
• Oil intake report. It is possible to compare the liquid level before and after oil intake. Automatically calculate and save the amount of oil in and out.
• Communication function. The system is connected to the sensor through a 485 interface for data collection. At the same time, it can provide a built-in Ethernet interface, 2 RS-232 interfaces and an open protocol. Data communication with the local system and remote server.
• Product lightning protection design. With internal lightning protection and external lightning protection functions. In the event of a lightning strike, the internal circuit automatically discharges the strong lightning current and will not detonate or ignite combustible gas. The external wiring steel pipe is connected to the protective grounding system of the storage tank.
• Active communication and timing transmission data settings. The system can use external equipment to achieve active communication settings. Be able to set the target server IP address, port, user name, password and data sending time. And upload the data to the target server at the specified time and shift shift.
• Leak detection function. Due to the high measurement accuracy, the static and dynamic liquid level of the oil tank can be monitored in real time. It can also realize pipeline leakage monitoring in accordance with pipeline leakage testing procedures.

Extended reading: Oil Level Measurement Solutions for the Oil & Gas Industry

Since Sinochem’s Zhuhai Phase II oil depot currently does not have the oil intake conditions, the instrument and system cannot be fully tested and verified. But through other petrochemical companies have used the magnetostrictive level gauge as an oil tank level monitoring system for in-depth understanding. The above-described functions can all be realized, and the measurement accuracy function is carefully compared with the manual ruler. It is found that the accuracy is very high, basically reaching the level of measurement.

In summary, the magnetostrictive level gauge has outstanding advantages such as high reliability, high accuracy, low failure rate, and multi-parameter measurement. It has been regarded by experts in the petrochemical industry as the preferred instrument for liquid level and boundary level measurement. It is an ideal choice for metering and process-level monitoring. Especially in applications where the dielectric constant of the medium is low, the medium is volatile, and the measurement interface is required. Because the magnetostrictive characteristics are not affected by factors such as dielectric constant, temperature, pressure, and meteorological conditions, it has become the first choice for users. Under the trend of industrial production integration and large-scale production. Magnetostrictive level gauges will have a broader application space in future level measurement.

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