Ultrasonic liquid level sensors realize the non-contact continuous detection of liquid level.
Ultrasonic liquid level sensors echo sounding sensors for measuring liquid level. And converting it to an electrical signal to send to other instrumentation. Ultrasonic Level Transmitters & Ultrasonic Level Sensors can be used for Non-intrusive level detection of sealed tanks. It can be used for liquid level detection of unsealed tanks and open channels such as rivers.
Portable Ultrasonic Liquid Level Indicator allows you to conveniently detect the level of liquid available in a container /cylinder/pipe/tank. Ultrasonic principle, Non-contact.
Ultrasonic level sensor can adopt two-wire, three-wire or four-wire technology.
The two-wire system is: power supply and signal output are shared. The three-wire system is: the power supply circuit and the signal output circuit are independent. When using DC 24v power supply, a 3-core cable can be used, and the negative terminal of the power supply and the negative terminal of the signal output share a core wire. The four-wire system is: when using AC 220v power supply, or when using DC 24v power supply, when the power supply circuit and the signal output circuit are required to be completely isolated, a 4-core cable should be used. DC or AC power supply, 4~20mADC, high and low switch output.
Ultrasonic transducer (probe) emits high-frequency pulse sound waves, and the surface of the measured level (material) is reflected back. The reflected echo is received by the transducer and converted into an electrical signal. The propagation time of the 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 and the sound speed C and the sound transmission time T can be expressed by the formula: S=C×T/2.
The probe part emits ultrasonic waves, which are then reflected by the liquid surface. The probe part is received again. The distance from the probe to the liquid (object) surface is proportional to the elapsed time of the ultrasonic wave: hb = CT2 Distance [m] = time × speed of sound/2 [m] The temperature compensation formula of sound velocity: Ambient sound velocity = 331.5 + 0.6 × temperature
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.
Ultrasonic level gauge is a sensor that emits ultrasonic waves. The sound waves are reflected by the liquid surface and then received by the same sensor. They are converted into electrical signals by piezoelectric crystals or magnetostrictive devices. The time between the transmission and reception of the sound waves is calculated to calculate the sensor The distance to the surface of the liquid being measured.
Very short microwave pulses with very low energy emitted by the radar level gauge are transmitted and received through the antenna system. Radar waves travel at the speed of light. The running time can be converted into a level signal by electronic components.
The radar level gauge is more accurate than the ultrasonic level. And the ultrasonic level gauge is not accurate when measuring the liquid level that produces the foam. Because the ultrasonic wave is reflected back when it hits the foam, the measured level is higher than the actual level. So The radar level gauge is used for the liquid level that is prone to foam. The microwave used by the radar level gauge can pass through foam. So it can also be used for level measurement of liquids that are prone to foam.
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.
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.
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.
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.
Ultrasonic liquid level sensor is a digital liquid level meter controlled by microprocessor. Ultrasonic pulses are emitted by sensors (transducers) during the measurement. The sound waves are picked up by the same sensor after being reflected off the surface of the liquid. Converted into electrical signals by piezoelectric crystals. And the distance between the sensor and the liquid surface to be measured is calculated from the time between the emission and reception of the sound wave. Because of the non-contact measurement. The measured medium is almost unlimited. It can be widely used to measure the height of various liquid and solid materials.
The working principle of the ultrasonic water level sensor is that the ultrasonic transducer (probe) emits high-frequency pulsed sound waves when it encounters the water surface and is reflected and folded back. The reflected echoes are received by the transducer and converted into electrical signals. The propagation time of a sound wave is proportional to the distance from the sound wave to the surface of the water.
Ultrasonic water level sensor is often used for water level monitoring in sewage stations, fire water tanks, reservoirs, etc.
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What Is Radar Type Level Transmitter? The Radar Type Level Transmitter is a kind of instrument that measures the liquid level in the container by microwave. The Radar Type Level…
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Non-contact radar level sensor Radar level sensors are used for continuous non-contact level measurement of liquids or solids. And convert it into electrical signals. The radar level sensor emits high-frequency…
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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.
Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.
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 co2 bottle liquid level gauge uses ultrasonic non-contact measurement technology. Detect and display the presence or absence of the Co2 cylinder liquid level. The Digital portable liquid level gauges are designed to offer a simple, accurate, rapid and reliable method. Determining the liquid level of high or low pressure CO2, Halon, FM200, Propane, Novec 1230 and any liquefied gas under pressure. No need to move or weigh the cylinders.
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.
Features: Large graphic display ~ Automatic rapid set up ~ Temperature gauge in C & F to enable fast weight calculations ~ Smart plug-in to enable signal strength to be monitored as an audible signal from the internal speaker ~ Power boost facility for cylinders in poor condition ~ Cylinder wall thickness selector for thick (>4mm) or thin (<4mm) walled cylinders.
Unit Dimensions: 210 x 130 x 55mm
Unit Weight: 540g (including batteries and leather case)
Sensor: 1.5m cable and magnetic clamp for hands-free use
Sensor Dimensions: 95 x 60 x 60mm
Temperature Range: -10ºC to +50ºC*
94cm-long extension arm
Power Supply: 4 x AA batteries
Battery Life: 20 hours nominal with 4 x AA batteries
Carry Case Dimensions: 450 x 370 x 100mm
Operational Weight: 650g
Shipping Weight: 2.5Kg
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.
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:
Select “co2 cylinder”-“Choose a suitable cylinder diameter” through the menu and enter the measurement interface.
Hold the probe vertically and tightly on the tank, and press the <Measure> button to measure.
Measurement results are based on measurement parameters and level indicator lights (red is “no liquid”, green is “with liquid”)
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).
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).
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).
Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.
Monitoring the level of liquid chlorine storage tanks is a common problem in the chlor-alkali industry.
In the chlorine production process, sulfuric acid dehydration is used to dry the chlorine. There will be a small amount of acid mud in the liquid chlorine. Liquid chlorine is highly toxic and corrosive. Liquid chlorine storage tank level measurement must take into account the requirements of corrosion resistance, safety requirements, reliability, convenient installation and easy maintenance.
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.
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.
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 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.
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 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.
Therefore, the external level gauge is to continuously and accurately measure the height of the liquid level in the tank from the outside of the tank. It does not touch the liquid and gas in the tank at all, realizing a true isolation measurement.
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.
Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.
Magnetostrictive level gauge application tutorial. Just one article to help you understand !
This article introduces the installation method and typical application of magnetostrictive level gauge in depth. Help you fully understand the structure and selection of magnetostrictive level gauges.
Sino-Inst offers a variety of Magnetostrictive level gauges for level measurement. If you have any questions, please contact our sales engineers.
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.
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
◆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
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.
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
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.
Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.
The magnetostrictive level gauge is applied to the information system of the refined oil storage tank oil depot. Real-time monitoring and measurement management of refined oil storage tanks.
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).
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.
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.
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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Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.
The liquid level of the liquid ammonia storage tank is accurately measured, which can eliminate potential safety hazards.
Choosing a suitable monitoring instrument for liquid ammonia storage is a prerequisite for ensuring safe production. The main instruments in the liquid ammonia tank area include liquid level, temperature, pressure, toxic (flammable) gas alarms, etc. For tank farms where the system is rebuilt, and environments where wiring is difficult, wireless instrumentation solutions can be used.
This article analyzes the application problems of several common liquid ammonia storage tank level measuring instruments. So as to provide a basis for the selection of measuring instruments.
About Liquid Ammonia Storage Tank
Liquid ammonia is a common chemical raw material. To facilitate transportation and storage, gaseous ammonia is usually pressurized or cooled to obtain liquid ammonia. When liquid ammonia is dissolved in water, ammonium ion NH4+ and hydroxide ion OH- are formed, and the solution is alkaline. Liquid ammonia is mostly stored in pressure cylinders or steel tanks. Liquid ammonia is widely used in industry, is corrosive and easily volatile, so its chemical accident rate is very high.
Application Analysis of Common liquid Ammonia Storage Tank Level Measuring Instruments
External liquid level sensor
The external level gauge is an instrument that uses the sonar ranging principle and “micro-vibration analysis” technology to measure the level from the outside of the container. No need to make holes on the tank wall, no flanges, no fire, no tank cleaning. Do not touch the liquid and gas in the tank. It can realize online installation and maintenance. It is a completely non-contact isolated instrument.
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.
The external liquid level sensor continuously and accurately measures the liquid level in the tank from outside the tank. No contact with the liquid and gas in the tank at all, realizing a true isolation measurement. Therefore, the characteristics are as follows:
Installation and debugging, thereby reducing construction and maintenance costs.
It is more reliable and durable. There are no mechanical moving parts in the measuring probe and host, and it is strictly sealed, isolated from the outside world, and will not be worn or corroded.
Pass the “functional safety integrity” level certification.
In the process of applying this instrument and equipment, it is necessary to strictly control the installation height of the equipment.
Generally, it needs to be installed below the lower interface of the liquid level pressure interface of the container under test. And choose easy to maintain and observe. At the same time, it is also close to the pressure taking part.
Taking into account the low boiling point and easy vaporization of liquid ammonia, it is necessary to use a double flange differential pressure transmitter to ensure the stability of the measurement signal.
If this device is used, the installation of the device will only be limited by the length of the capillary tube.
Specifically, it is necessary to take corresponding protection and insulation measures, and ensure that the bending radius of the capillary is greater than 50mm. When using this measuring instrument, if the installation elevation changes, the output value of the device will be affected.
Differential pressure(DP) level transmitter is often used as a tank level transmitter. The DP transmitter is connected with a stainless steel flange by capillary. Flange installation. The pressure is sensed by a remote transmission device installed on container. The pressure is transmitted to the body of the transmitter through the capillary. The transmitter convert the pressure or differential pressure to 4 ~ 20mA. The DC signal is output. It can communicate for the setting and monitoring by cooperating with the HART communicator. Explosion proof available.
From the application effect point of view, the differential pressure transmitter has the characteristics of easy calibration and a wide range of popularization. At the same time, the price of this type of equipment is low, and it has a certain cost-effective advantage.
However, when installing the device, it is necessary to reserve mounting holes. At the same time, due to the close relationship between the equipment and the density change of the medium, the measurement operation will cause the material of the instrument diaphragm to be corroded by the corrosive medium. After a long time of operation, the equipment is prone to deformation of the capsule.
In the application process, if there is no indication, the indication is too large or too small and the indication remains unchanged. It is also necessary to check the power supply, safety barriers, circuit boards, diaphragm capillaries and pressure valves. And appropriately replace the equipment components and open the equipment pressure valve in time.
During the measurement, the two-color cylindrical magnetic float inside the device will change under the influence of the magnetic field, and the float junction is the actual liquid level of the storage tank.
In the process of installing the equipment, it is necessary to avoid magnetic materials around the equipment, and determine the heating temperature according to the medium condition. In the case of large gas-liquid-phase opening connections, a flange needs to be installed in the middle of the level gauge.
In the process of equipment debugging, a magnetic steel corrector is needed to adjust the magnetic column to white, and then open the gas phase stop valve and the liquid phase stop valve successively, and observe the liquid level rise and fall.
The magnetic flap level gauge can measure the liquid level and interface of any medium, and the equipment itself has the characteristics of convenient and intuitive installation.
However, if there are too many impurities in the medium, the magnetic column will not flip and the measurement will fail.
At the same time, the application of this device is prone to the problem of magnetic column jamming, which will lead to the failure of remote transmission instructions. However, the price of this equipment is low, and installation holes need to be reserved during installation.
The magnetic flap level gauge is prone to problems such as no signal output from the transmitter, no change in the output signal and the range cannot be adjusted to the corresponding value during the application process. In the application process, the power supply voltage, cables, terminal pins and safety barriers need to be checked.
Cable guided wave radar liquid level sensor
The application of the cable guided wave radar level gauge follows the principle of travel time, and it is necessary to measure the distance from the reference point to the surface of the liquid ammonia by transmitting and receiving high-frequency pulse signals.
When installing the equipment, it is necessary to avoid the liquid ammonia inlet to prevent false reflections from the equipment.
When installing the sensor, it cannot be installed in the center of the tank, and the sensor must be kept away from the tank wall.
When installing the cable probe, the distance between the probe and the smooth metal wall should be greater than 50mm, the distance between the end of the probe and the bottom of the container should be greater than 0mm, and the diameter of the short tube should not be greater than 0mm. In addition, depending on the installation position, the offset of the cable probe may increase.
Guided wave radar is a measuring instrument based on the principle of time travel. The radar wave runs at the speed of light. The operating time can be converted into level signals by electronic components. The probe emits high-frequency pulses and propagates along the cable or rod probe. When the pulse meets the surface of the material, it is reflected back and received by the receiver in the instrument. And convert the distance signal into level signal. SIRD-701 Guided Wave Radar Level Sensor is suitable for liquid and Bulk Solids measurement, and complex process conditions.
The cable-type guided wave radar level gauge has the characteristics of direct contact with the medium and small measurement blind area, and the measurement accuracy is high.
However, this equipment is not suitable for measuring pressure vessels, and the price is relatively high. It is necessary to reserve mounting holes on the top of the equipment during installation.
From the point of view of application failures, the equipment may have failures such as incorrect DCS system configuration, cable probe failure, and unstable DCS display value.
In the application process, it is necessary to carry out on-site measurement before calibration, and it is not necessary to check whether the DCS configuration data is consistent with the actual measurement result in order to obtain the real data.
Before measurement, you need to clean the probe and increase the height of the empty tank appropriately to eliminate the effect of echo.
Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.
Differential Pressure Level transmitter for Continuous tank level measurement.
A liquid level measurement solution that prevents the measured medium from directly acting on the transmitter.itle
In the chemical production, the medium often encounters problems such as impurities, crystal particles or agglomeration. It is easy to block the connecting pipeline. At this time, a flange-type differential pressure transmitter is required.
Silicone oil is filled in the closed system composed of the bellows, capillary tube and measuring chamber as the pressure transmission medium. The measured medium does not enter the capillary tube and the transmitter to avoid blockage.
Differential Pressure Level transmitters are divided into single flange type and double flange type according to their structure.
Only a flange between the container and the transmitter is called a single flange differential pressure transmitter.
As for the closed container whose upper end is isolated from the atmosphere, the upper space and atmospheric pressure are mostly different. Two flanges must be used to guide the liquid and gas phase pressure to the differential pressure transmitter. This is the double flange differential pressure transmitter.
Differential Pressure Level transmitter for open containers
Open tank level measurement means that the tank is open to the atmosphere. Any change in atmospheric pressure will affect the process fluid pressure in the tank. In this liquid level measurement application, the low pressure side of the transmitter can measure the atmospheric pressure. This eliminates the influence of atmospheric pressure on the tank liquid level. The high-pressure side of the transmitter is connected to the tank. Therefore, the actual liquid level in the tank can be measured.
A single flange is used to measure the liquid level of an open tank.
Differential pressure range calculation method: Need to measure the height of the liquid level (unit: m) × acceleration of gravity (9.8) × measured medium density (unit: g/cm3) differential pressure range (unit: KPa).
The selection must know the measurement medium, measuring range, medium temperature, the size and pressure rating of the process connection flange, and the flange standard.
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
Differential pressure level transmitter working principle
When using Differential pressure (DP) level transmitter to measure the liquid level as shown in the figure below. The measured liquid density in the figure is ρ. The working medium density in the capillary of the double flange differential pressure transmitter is ρ0. The measuring range of the measured liquid level is H. The center distance of the sampling tube of the measured liquid level is h. It can be seen from the figure that the maximum measurement range of the liquid level △ P = P + —P- = H × ρ × g-h × ρ0 × g.
It can be seen from the formula that the dual-flange differential pressure transmitter should perform negative migration. The migration amount S is h × ρ0 × g. And the installation position of the double flange differential pressure transmitter has no effect on the migration amount and the measurement result.
The dual-flange differential pressure transmitter requires negative migration.
When the measured liquid level is 0, the pressure difference between the positive and negative measurement chambers of the remote differential pressure transmitter is the largest. The output current of the double flange differential pressure transmitter is 4mA.
As the measured liquid level rises, the pressure difference between the positive and negative measurement chambers of the transmitter gradually decreases.
When the measured liquid level rises to the highest Hmax. The pressure difference between the positive and negative measurement chambers of the transmitter is the smallest. The output current of the double flange differential pressure transmitter is 20mA.
Sino-Inst offers overs 100 DP transmitters for liquid level, pressure, flow, temperature measurement. Differential pressure (dp) level transmitters suit to measeure water and other liquid level.
A wide variety of DP level transmitters are available to you. Such as SMT3151LT Differential pressure level transmitter.
You can also choose from liquid flow meter and pressure transmitters, not specified. We are differential pressure level transmitter suppliers, located in China. The top supplying country is China(Mainland), which supply 100% of DP transmiters respectively.
Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.
The external ultrasonic tank level sensors is the first choice for measuring liquid level and material level on various industrial tanks.
The intelligent ultrasonic tank level sensor installs the ultrasonic probe directly under the tank when measuring. No need to open holes, easy to install. Does not affect on-site production. It can measure various toxic substances and pure liquids in high temperature and high pressure airtight containers. The instrument adopts explosion-proof design to meet explosion-proof requirements. The Internet of Things can be realized through GPRS and Wifi.
Sino-Inst offers a variety of ultrasonic level meters for tank level measurement. If you have any questions, please contact our sales engineers.
The probe is external, no need to open a hole to the container under test.. Really realize non-contact measurement.
It is suitable for accurate measurement of the liquid level of toxic, volatile, flammable, explosive, and highly corrosive liquid media in various closed containers.
The instrument has no mechanical moving parts and has a long life. No corrosion, no pollution, wide use area.
The instrument has built-in ASIC (Intelligent Ultrasonic Special Hardware Integrated Circuit), which makes the instrument small in size, stable and reliable in measurement results. It can be suitable for all kinds of liquids and containers to be tested, and it is easy to install on site without complicated on-site calibration.
The instrument has built-in various calibration functions such as automatic temperature correction and automatic fixed distance calibration. The measurement results are more accurate and reliable.
The instrument has complete functions, with RS485 output, 4-20mA output, and switch output.
Multiple power supply methods available
Backup and restore configuration parameters
The analog output can be adjusted arbitrarily
With digital filtering and echo recognition functions
Fixed interference filtering function can be manually set
Support Bluetooth, GPRS communication, GPS satellite positioning, etc. (Order to buy)
Support custom serial data format
Support custom main display interface
Support MiniSD card data collection (order option)
the liquid cannot be filled with dense bubbles. A large amount of solids, such as crystals, cannot be suspended in the liquid.The bottom of the container cannot deposit a large amount of sand and sediment.
Medium Viscosity
When the dynamic viscosity is less than 10mPaS, it is measured normally. When 10mPaS<dynamic viscosity<30mPaS, the range of the instrument may be reduced. It cannot be measured when the dynamic viscosity is >30mPaS.
note: As the temperature increases, the viscosity decreases, and most high-viscosity liquids are more affected by temperature. Therefore, pay attention to the effect of liquid temperature when measuring viscous liquids.
Container Under Test
Material: The container wall where the measuring probe is installed is required to be made of hard materials that can transmit signals well. Examples: carbon steel, stainless steel, various hard metals, glass steel, hard plastics, ceramics, glass, hard rubber and other materials or their composite materials. If the container wall where the measuring probe is installed is of multilayer material, the layers should be in close contact with no bubbles or gas interlayers. The inner and outer surfaces of the container wall should be flat. Examples: vulcanized hard rubber lining, stainless steel lining, titanium lining Floor.
Wall thickness: 1-100mm
Tank type: spherical tank, horizontal tank, vertical tank, etc.
Probe Installation Requirements:
For iron containers, you can apply silicone grease to the working end of the probe and stick it directly to the bottom of the container with a magnetic suction cup; if the container shell is made of glass or other materials, you can use glue to fix the probe or use a bracket to fix it. The bottom of the container. The probe point must be on the same straight line as the measured distance.
There are no obstructions such as coils directly above the probe;
Keep away from the liquid inlet at the bottom of the tank to avoid the influence of the violent flow of the liquid on the measurement;
Keep away from the position below the liquid inlet on the top of the tank to avoid the impact of the liquid inlet and the violent fluctuation of the liquid level to affect the measurement;
It is higher than the liquid outlet or the sewage outlet to avoid the influence of long-term deposits on the bottom of the tank on the measurement. If the conditions are not met, measures should be taken to ensure that the bottom of the tank is regularly removed;
When the liquid level measuring head is installed by magnetic or welding/adhesive fixing method, the installation surface size on the container wall should not be less than the round surface of Ф80, the surface roughness should reach 1.6, and the inclination should be less than 3°(bypass pipe exce
Ultrasonic level meter is a high-tech product that integrates ultrasound, electronics and software. The various indicators of the ultrasonic level meter have reached the advanced level of similar products in the world. and it is the first-choice instrument for measuring liquid level and material level on various industrial sites.
How Do External Ultrasonic Tank Level Sensors Work?
Install the ultrasonic probe directly below the outer wall of the container under test. No need to open holes, easy to install, and does not affect on-site production. It can accurately measure various toxic substances and various pure liquids in high temperature and high pressure airtight containers.The instrument has built-in ASIC (Intelligent Ultrasonic Special Hardware Integrated Circuit), which makes the instrument small in size, stable and reliable in measurement results, and can be suitable for various liquids and containers to be tested. It is easy to install on site and does not require complex on-site calibration.
The instrument has built-in various calibration functions such as automatic temperature correction and automatic fixed distance calibration to make the measurement results more accurate and reliable. The Internet of Things can be realized through GPRS and Wifi.
How Do You Mount An External Ultrasonic Tank Level Sensor?
The probe is installed externally, no need to open a hole in the container to be tested, and truly realize non-contact measurement.It is suitable for accurate measurement of the liquid level of toxic, volatile, flammable, explosive, strong pressure, strong corrosive and other liquid media in various closed containers.The instrument has no mechanical moving parts and has a long life. No corrosion, no pollution, wide use area.
What Are The Benefits?
Safe : No valves, connecting pipes, joints, no leaks, no contact with the liquid and gas in the tank, very safe, when measuring toxic, corrosive, pressure, flammable, volatile, and easy to leak liquids
Hygiene: liquid level detection and monitoring projects in brewing, beverages, milk production, storage tanks, pipelines, etc. do not come in contact with liquids and cause pollution.
Convenient installation and maintenance: no fire or tank cleaning during installation and maintenance will not affect production.
When measuring the External Ultrasonic Tank Level Sensor, install the ultrasonic probe directly under the outer wall (bottom) of the container under test. No need to open holes, easy to install, and does not affect on-site production. It can be used to treat various toxic substances in high temperature and high pressure airtight containers. Accurate measurement of a pure liquid.
The External Ultrasonic Tank Level Sensor adopts explosion-proof design to meet explosion-proof requirements. The probe is installed externally, no need to open a hole in the container to be tested, real non-contact measurement, suitable for accurate liquid level of toxic, volatile, flammable, explosive, strong pressure, strong corrosive and other liquid media in various closed containers measuring.
The External Ultrasonic Tank Level Sensor has no mechanical moving parts and has a long life. No corrosion, no pollution, wide use area. More about Top 5 Ultrasonic Level Sensor Applications.
In the design work, a reasonable and optimized External Ultrasonic Tank Level Sensor selection scheme was made according to each project. Judging from the production and application, the effect is very good.
1.Field application of butadiene
In a rubber project, it is necessary to measure the level of butadiene in the spherical tank. Butadiene is prone to self-polymerization to produce high molecular polymers, and the selection of ordinary liquid level meters is limited. According to the requirements of “Tank Area Automation System Design Regulations”, “Each pressure storage tank should be equipped with two sets of independent and different types of liquid level measuring instruments”. If the conventional contact liquid level gauge is selected for this project, butadiene is at the dead corner of the detection port The possibility of self-aggregation is very large, so the non-contact type should be given priority to the selection of the level gauge. Finally, a set of non-contact radar level gauges were installed on the top of the tank, and a set of External Ultrasonic Tank Level Sensors were installed on the bottom of the tank. After the field application, the externally attached ultrasonic level gauge measures accurately and the effect is very good.
2.Field application of liquid ammonia
In the design of a certain liquid ammonia spherical tank, the External Ultrasonic Tank Level Sensor also has a good application. The liquid ammonia in the storage tank is a colorless, pungent odor and toxic liquid, which is corrosive to a certain extent. Because the density of liquid ammonia is greatly affected by temperature, the differential pressure level gauge is not applicable in this project, and the external ultrasonic level gauge is finally used for detection.
3.Field application of high pressure storage tank
In a high-pressure hydrogenation plant, due to the unstable parameters of the original level gauge on the high-pressure storage tank, the owner wanted to add a level gauge to compare with it. However, the installation space of the high-pressure vessel was small on site, and the conditions for reopening were not available. After negotiation, it was decided to adopt an external ultrasonic level gauge, which not only avoided the economic loss caused by the shutdown of the device, but also prevented new pressure vessels. Increase the safety hazards of leakage points, simple installation, accurate and reliable, can be described as three birds with one stone.
4.Ultrasonic sensor for Oil/fuel level measurement
The External Ultrasonic Tank Level Sensor adopts explosion-proof design to meet explosion-proof requirements. The probe is installed externally, no need to open a hole in the container to be tested, real non-contact measurement, suitable for accurate liquid level of toxic, volatile, flammable, explosive, strong pressure, strong corrosive and other liquid media in various closed containers measuring. Therefore, the External Ultrasonic Tank Level Sensor is the best level measurement sensor for diesel, gasoline and other oil tanks. More about Diesel Fuel Level Sensor Types.
5. Other field applications
The External Ultrasonic Tank Level Sensor can be a good substitute for radar level gauges in some occasions where the dielectric constant is low, such as liquefied gas (dielectric constant <1.9) or the liquid surface contains a lot of bubbles and other radar level gauges are not suitable for use; For some highly corrosive acid and alkali storage tanks, such as liquid chlorine storage tanks, the External Ultrasonic Tank Level Sensor is also very useful.
External Ultrasonic Tank Level Sensor common available media include liquid chlorine, liquefied gas, liquid ammonia, ethylene, butadiene, gasoline, diesel, benzene, liquid bromine, hydrochloric acid, lye, nitric acid, methanol, vinyl chloride, hydrofluoric acid, ethylene Glycol, propane, naphtha, ethylene oxide, dimethyl ether.
Can External Ultrasonic Tank Level Sensors Detect Water Level?
Ultrasonic liquid level sensor can be used for water level measurement. The principle of ultrasonic reflection used. According to the contact between the sound wave emitted by the pool ultrasonic liquid level gauge and the liquid surface. According to the length of time it reflects back. To measure the height of the liquid level in the tank. Liquid level sensors are used in many sites to detect some conditions that require liquid level monitoring. It is well known that the liquid level of some sewage treatment tanks, the liquid level on the tank, the liquid level on the river channel and so on.
What is an ultrasonic level sensor?
Ultrasonic level sensor is a monitoring instrument for measuring liquid height, tank height, and material position.
Ultrasonic level sensor can adopt two-wire, three-wire or four-wire technology.
The two-wire system is: power supply and signal output are shared. The three-wire system is: the power supply circuit and the signal output circuit are independent. When using DC 24v power supply, a 3-core cable can be used, and the negative terminal of the power supply and the negative terminal of the signal output share a core wire. The four-wire system is: when using AC 220v power supply, or when using DC 24v power supply, when the power supply circuit and the signal output circuit are required to be completely isolated, a 4-core cable should be used. DC or AC power supply, 4~20mADC, high and low switch output.
There are 7 main types of level transmitters that Sino-Inst offers for water level indicate. Each type of transmitter works in a different way, and makes it useful for different types of processes.
Sino-Inst offers over 10 External Ultrasonic Tank Level Sensors and transmitters for level measurement. About 50% of these are liquid level meters, 40% is the level switches.
A wide variety of External Ultrasonic Tank Level Sensors and transmitters options are available to you, such as free samples, paid samples.
Sino-Inst is a globally recognized supplier and manufacturer of External Ultrasonic Tank Level Sensors and transmitters instrumentation, located in China.
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Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.
The ultrasonic liquid level sensor is a non-contact measuring device. That can send and receive high-frequency sound waves to measure the distance to the surface of liquid-based materials.
The ultrasonic liquid level measurement uses the non-contact principle. It is most suitable for level measurement of hot, corrosive, and boiling liquids. It is used to measure liquid levels. Ultrasonic equipment that converts it into electrical signals to send to other instruments.
Sino-Inst offers a variety of ultrasonic liquid level sensors and transmitters for continuous, non-contact tank level measurement. If you have any questions, please contact our sales engineers.
The liquid level sensor is a pressure sensor that measures liquid level. The static pressure input type liquid level transmitter is based on the principle that the measured liquid static pressure is proportional to the height of the liquid. It uses an isolated diffused silicon sensor or a ceramic capacitive pressure sensitive sensor to convert the static pressure into an electrical signal. Temperature compensation and linear correction are converted into standard electrical signals (usually 4~20mA/1~5VDC)
The working principle of the ultrasonic level gauge: The high-frequency pulse sound wave emitted by the ultrasonic transducer is reflected on the surface of the measured level, and the reflected echo is received by the transducer and converted into an electrical signal. The propagation time of the sound wave is proportional to the distance from the sound wave to the surface of the object. The relationship between sound wave transmission distance S and sound speed C and sound transmission time T can be expressed by the formula: S=C×T/2.
According to the characteristics of ultrasound, it is actually more suitable for occasions where the accuracy requirements are not high and the working environment is not harsh.
Water treatment industry.
Water treatment industry, including sewage treatment, tap water, pure water manufacturing and other occasions.
The measured medium is basically sewage and clean water, which does not require high measurement accuracy. And the working environment is basically not corrosive, there is no electromagnetic interference, and most of them work in the open air. At most, large waves are encountered where the water enters, or there is a small amount of foam on the water surface.
Water conservancy and hydrology Water conservancy and hydrology industry.
In the early years, it was mainly used to measure water level changes at the gate. In recent years, because the state has increased its investment in the water conservancy industry. Flash flood warnings and water level and rainfall monitoring must be carried out in small and medium river basins.
These occasions basically need 24VDC power supply and RS485 output.
Because they are all measured on the water surface, there is no requirement for the launch angle of the ultrasonic level gauge. There will be no volatility and foam influence.
It is generally carried out on a relatively wide channel. Small channels generally do not need to be measured.
The common channel width is more than 1 meter.
4. Chemical companies mainly need anti-corrosion and explosion-proof ultrasonic level gauges.
Liquids in chemical companies are measured by ultrasonic waves, which are basically in storage tanks.
For example: sulfuric acid, hydrochloric acid, liquid caustic soda, toluene, xylene, olefin, ammonia, acetone, etc. These occasions can be solved with an ultrasonic level gauge. If it is in the reactor, it will be affected by stirring.
There should be no obstacles under the sound wave. Because the ultrasonic level sensor uses the principle of sound wave reflection to achieve liquid level measurement. If there are obstacles, it will affect the ultrasonic emission. It will cause signal loss and affect the measurement effect.
The measurement of ultrasonic level sensor is prone to blind spots. This is because in the ultrasonic pulse transmission process. Because the mechanical inertia occupies the transmission time. Therefore, the small area near the ultrasonic transducer cannot receive the sound wave. The area that cannot be measured is called the blind zone. The size of the blind zone is related to the ultrasonic measurement distance. The smaller the measuring distance, the smaller the blind zone. The larger the measuring distance, the larger the blind zone.
The measurement of ultrasonic level sensor is easily affected by temperature. In actual measurement, changes in temperature will cause changes in the speed of sound. This will lead to errors in the measurement.
It is not suitable to measure pressure vessels. Because the pressure mainly affects the probe. And there is a certain relationship between pressure and temperature. Pressure changes will affect the temperature changes, which in turn affects the speed of sound. The accuracy of the measurement is affected.
Radar Level Transmitter is an application of microwave (radar) positioning technology in level measuring instruments. It transmits energy waves through a device that can emit energy waves (usually pulse signals). The energy waves are reflected when they encounter obstacles, and the reflected signals are received by a receiving device.
According to the time difference of the energy wave movement process, the level change can be determined. The microwave signal is processed by the electronic device. Finally, the microwave signal is converted into an electrical signal related to the level.
The basic principle of ultrasonic measurement of liquid level is: the ultrasonic pulse signal sent by the ultrasonic probe propagates in the gas, and is reflected after encountering the interface of air and liquid. After receiving the echo signal, calculate the propagation time of the ultrasonic wave. Convert the distance or liquid level height.
Common Applications for Ultrasonic Liquid Level Sensors
Ultrasonic liquid level sensor integrates three functions of non-contact switch, controller and transmitter. Suitable for small storage tanks. In integrated systems or replace float switches, conductivity switches and static pressure sensors. It is also suitable for integrated applications in fluid control and chemical supply systems. for machinery, brakes and other equipment The application of small storage tanks is also a good choice.
Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.
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.
Liquefied petroleum gas is one of the most widely used fuels in civil and industrial production. During the storage and transportation of liquefied petroleum gas, liquid level measurement is an important task of the project. It is required not only to have high accuracy for liquid level measurement. It must also be able to adapt well to the working conditions of closed pressure vessels. At the same time, in order to meet the needs of remote monitoring and management. It must also require the measurement data to have the function of long-distance transmission.
Featured Level Sensors for Tank Level Measurement
Comparison of the common detection methods for the Tank Level Measurement
There are 7 main types of level transmitters that Sino-Inst offers for Tank Level Measurement. Each type of transmitter works in a different way, and makes it useful for different types of processes.
(1) Optical fiber level gauge Based on optical technology. Use optical fiber as the sensor unit. Take out the sensitive state as an optical signal. Then photoelectric conversion. So it is easy to match with highly developed electronic control devices.
Compared with other conventional sensors, optical fiber sensors have high sensitivity, fast response speed, and strong resistance to electromagnetic interference. Corrosion resistance, good electrical insulation, small size and easy to form a remote monitoring network with optical fiber transmission system. Especially in the harsh environment of flammable and explosive, it is widely used.
Cause the bridge to be unbalanced. The circuit outputs a voltage corresponding to the liquid level height. In order to obtain the liquid level signal. It has the characteristics of high precision (0.7%), small drift and strong anti-overload capability.
But when the density of the medium changes with the temperature, pressure and composition of the medium, the differential pressure level gauge will produce a false level.
(3) Servo level gauge. The servo liquid level gauge controls the float to follow the liquid level or interface changes through the servo motor. The servo float level gauge is subjected to different buoyancy forces on the liquid surface, in the liquid and on the interface through the float.
The gravity sensor is used to measure the weight of the float. It can send out long-distance signals at the same time. Use microcomputer for remote control. Its dynamic tracking error can reach 0.1mm.
At the same time, it can also compensate for the additional weight error caused by the low liquid level. The measurement accuracy of the liquid level can reach 0.7mm. The sensitivity can reach 0.1mm.
In addition, it also has self-diagnosis and communication functions. The level gauge has high reliability. But the price is relatively high.
(4) Radar level gaugeThe use of radar waves to measure the liquid level is a technology that has been paid close attention at home and abroad in recent years. It uses a horn-shaped waveguide to emit low-power microwaves (tens of microwatts).
After encountering the tested interface, part of the microwave is reflected back. Received by the transmitter and receiver combination level gauge system. Indirectly measure the liquid level by measuring the time difference between transmission and reception.
The biggest feature of the radar level gauge is that it is suitable for the environment where the application effect of the ultrasonic level gauge is not ideal.
Advantages of stainless steel magnetostrictive level sensor for oil Tank Level Measurement:
High precision: the magnetostrictive liquid level gauge uses waveguide pulse to work. During the work, the measured displacement is determined by measuring the time of the start pulse and the end pulse. Therefore, its measurement accuracy is high. The resolution is better than 0.01% FS. This is an accuracy that is difficult to achieve with other sensors.
Strong reliability: Because the magnetostrictive liquid level gauge uses the waveguide principle. There are no mechanically movable parts. So there is no friction and no wear. The entire converter is enclosed in a stainless steel tube and does not contact the measuring medium. The sensor works more reliably and has a longer life.
Facilitate system automation: The secondary instrument of the magnetostrictive liquid level gauge adopts standard output signal. Help the computer to process the signal. It is easy to work on the Internet. Improve the automation of the entire measurement system.
Tank level measurement is a general term for measuring the static storage of liquid products in large storage tanks. It can be used for inventory measurement, which is to determine the total amount of products in the storage tank.
It can also be used for transmission and transfer measurement, that is, as a basis for product purchase, sale and tax payment. There are two main methods: volume-based and mass-based measurement.
Pressure level sensors can be used to establish levels in rivers, tanks, wells or other liquids. The pressure at the bottom of the liquid-filled container is directly related to the height of the liquid.
The transmitter measures this hydrostatic head and provides a final level. In order to obtain an accurate reading, the measuring device must be located at the lower point where you want to measure; it is usually installed or placed at the bottom of the container.
When measuring the liquid level, the specific gravity must be considered. Consider the following equation:
H = P / SG or P = SG? H
H-the height of the measured liquid. It is usually measured in inches, centimeters, meters, feet, etc. P-Hydrostatic head at the bottom of the tank. Usually in inches of water column, feet of water column, horizontal bar, psi, Pascal’s, etc. SG-the proportion of the medium. The dimensionless number is calculated from: measured medium density ÷ water density at 4 ° C. For example, the density of kerosene is equal to 0.82 g / cm 3. Therefore, the kerosene of SG is 0.82g / cm 3 · 1.00g / cm 3 = 0.82.
These transmitters work on the principle of a radar by using radio wave emissions. Mounted at the top of a tank filled with a liquid. The transmitter sends a radar signal into the liquid, and receives a reflection of the signal. The transmitters then analyze the current fill level of the tank based on the time taken by the transmitted signal to return.
Unaffected by sludge and biomass, dust, foam, oil, grease and other coatings, uneven surfaces, turbulence, pressure, and vacuum
Single frequency radar level sensors for liquid sensing, dual frequency radar level sensors for level measurement of aggregates, gravel, sand, coal, asphalt, and other solids
The water level sensor of your water tank is an essential component. If not repaired or replaced, a sensor can become damaged over time and fail entirely. Too much water can cause a malfunction and too little water means inadequate water pressure. Either way, repairing or replacing holding tanks is an expensive task you shouldn’t have to undertake because of sub-par sensors. With Sino-Inst’s water tank level sensors, there’s nothing to break down or rust and our models have a 99% success rate! In the high unlikely event that you experience any issues with your product, call us and we’ll replace or repair it immediately at no charge.
How do I test my water level?
Water pressure transducers also called a water pressure sensor, are pressure transmitters that can measure water pipe pressure. For the water level/water depth measurement, in the tank, or in the well, we can use electrical transmitters, stainless steel body, IP65-IP6, 4-20ma output.
Sino-Instrument offers over 10 level transmitters for tank level measurement. About 50% of these are liquid level meters, 40% is the tank level sensor.
A wide variety of level meters options are available to you, such as free samples, paid samples.
Sino-Instrument is a globally recognized supplier and manufacturer of level measurement instrumentation, located in China.
Request a Quote
Please enable JavaScript in your browser to submit the form
Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.
Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.