Process Engineering Division – Instrumentation and Automation Section – Daily Question – Question from 2020-08-07

1) Direct-reading level gauge； 2) Differential pressure level gauge ； 3) Float-type level gauge ； 4) Electromagnetic level gauge ； 5) Nuclear radiation type level gauge ； 6) Acoustic level gauge ； 7) Optical level gauge.

Static pressure, ultrasound, radar, float, magnetic flap

Requirements for level measuring instruments in industrial production: The main aspects include accuracy, range, cost-effectiveness, as well as safety and reliability, among which safety and reliability are of primary importance. Based on their working principle, level measurement instruments mainly fall into the following categories: (1) Direct-reading level instruments: These include glass tube level gauges, glass plate level gauges, and similar devices. (2) Differential pressure level gauges: These can be further divided into pressure-type level gauges and differential pressure type level gauges, and they operate on the principle that a liquid column or a pile of material exerts pressure on a specific point. (3) Buoyant level gauges: They operate on the principle that the height of a float changes as the liquid level changes, or that the buoyant force exerted by the liquid on a float (or sinker) submerged in the liquid changes with the liquid level. It can be further divided into types with a float equipped with a steel wire rope or steel strip, types with a float and a lever, and barrel-type types. (4) Electromagnetic level gauges: They convert changes in liquid level into changes in electrical quantities, and the level is determined by measuring these electrical changes. It can be divided into resistive (i.e., electrode-type), capacitive, and inductive level gauges, among others. There are also level gauges that operate using the magnetostrictive effect. (5) Nuclear radiation level gauge: It operates on the principle that the intensity of nuclear radiation decreases as it passes through a material layer, depending on the thickness of that layer. Gamma rays are currently the most widely used. (6) Acoustic property meters: As changes in liquid level cause variations in acoustic impedance, as well as differences in the obstruction of sound waves and their reflection distances, detecting these changes allows for the determination of the liquid level. Therefore, acoustic level gauges can be classified into acoustic interruption type, reflection type, and damping type based on their working principles. (7) Optical level gauge: It operates on the principle of the obstruction and reflection of light waves by the liquid level; the light source it uses can be a regular incandescent lamp or a laser, among others. In addition, there are other types of level gauges as well. Below, the differential pressure level gauge will be discussed in detail, while a brief overview of several other types of level measurement instruments is provided.

Differential pressure type, constant buoyancy type, variable buoyancy type, transmit-receive type, etc

What are the main types of level measurement instruments based on their working principles? I’ll answer. 1 answer. #Announcement# Announcement regarding the early release of the ranking for the high-quality video competition. Xian Ya Qing Yi Yao, 2019-06-27. Known as an answerer; number of answers given: 9654; acceptance rate: 0%; number of people helped: 0. I’ll also answer questions. Visit my personal page. Follow. Expand all. Based on their working principles, the main types of level measurement instruments are: 1. Direct-reading level instruments: These include glass tube level gauges and glass plate level gauges. 2. Differential pressure level gauges: These can be further divided into pressure-type level gauges and differential pressure type level gauges; they operate on the principle that a liquid column or a pile of material exerts pressure on a specific point. 3. Buoyant level instruments: They operate on the principle that the height of a float changes as the liquid level changes, or that the buoyancy exerted by the liquid on a float (or sinker) submerged in the liquid changes with the liquid level. It can be further divided into types with a float equipped with a steel wire rope or steel strip, types with a float and a lever, and barrel-type types. 4. Electromagnetic level gauges: They convert changes in liquid level into corresponding changes in electrical quantities, and the level is determined by measuring these electrical changes. It can be divided into resistive (i.e., electrode-type), capacitive, and inductive level gauges, among others. There are also level gauges that operate using the magnetostrictive effect. 5. Nuclear radiation level gauge: It operates on the principle that the intensity of nuclear radiation decreases as it passes through a material layer, depending on the thickness of that layer. Gamma rays are currently the most widely used. 6. Acoustic-type property meters: As changes in liquid level cause variations in acoustic impedance, as well as differences in the obstruction of sound waves and their reflection distances, by detecting these changes it is possible to determine the liquid level. Therefore, acoustic level gauges can be classified into acoustic interruption type, reflection type, and damping type based on their working principles. 7. Optical level gauge: It operates on the principle of light waves being blocked or reflected by the liquid level; the light source it uses can be an ordinary incandescent lamp or a laser, among others.

See Daily Question 20090303; P

Classification of level measurement instruments according to their working principle: (1) Direct-reading level instruments. These include glass tube level gauges, glass plate level gauges, etc. 　　(2) Differential pressure level gauges can be further divided into pressure-type and differential pressure-type types; they operate on the principle that a liquid column or a pile of material generates a static pressure at a fixed point. 　　(3) Buoyant level gauges operate on the principle that the height of a float changes as the liquid level changes, or that the buoyancy exerted by the liquid on a float (or float tube) submerged in the liquid changes with the liquid level. It can be further divided into several types: those with a float equipped with a steel wire rope (or steel belt), those with a float ball and a lever, and the barrel-type. 　　(4) Electromagnetic level gauges convert changes in liquid level into changes in electrical quantities, and the level is determined by measuring these electrical changes. It can be divided into resistive (i.e., electrode-type), capacitive, and inductive types, etc. There are also level gauges that operate using the magnetostrictive effect. 　　(5) Nuclear radiation level gauges operate on the principle that the intensity of nuclear radiation decreases as it passes through a material layer, with gamma rays being the most commonly used type at present. 　　(6) Acoustic level gauges detect level changes by measuring variations in acoustic impedance, interruptions in sound waves, and differences in the distance at which sound waves are reflected; by identifying these changes, it is possible to determine the level. Therefore, acoustic level gauges can be classified into acoustic interruption type, reflection type, and damping type based on their working principles. 　　(7) Optical level gauges operate on the principle of the level interfering with and reflecting light waves; the light source they use can be an ordinary incandescent lamp or a laser, among others.

Connecting tubes, pressure, reflective, capacitive, etc

(1) Direct-reading level gauge; (2) Differential pressure level gauge; (3) Buoyancy type level gauge; (4) Electromagnetic level gauge; (5) Radiation type level gauge; (6) Acoustic wave level gauge; (7) Optical level gauge.

1) Direct-reading level gauges: These include instruments such as glass tube level gauges and glass plate level gauges. (2) Differential pressure level gauges: These can be further divided into pressure-type level gauges and differential pressure type level gauges, and they operate on the principle that a liquid column or a pile of material exerts pressure on a specific point. (3) Buoyant level gauges: They operate on the principle that the height of a float changes as the liquid level changes, or that the buoyant force exerted by the liquid on a float (or sinker) submerged in the liquid changes with the liquid level. It can be further divided into types with a float equipped with a steel wire rope or steel strip, types with a float and a lever, and barrel-type types. (4) Electromagnetic level gauges: They convert changes in liquid level into changes in electrical quantities, and the level is determined by measuring these electrical changes. It can be divided into resistive (i.e., electrode-type), capacitive, and inductive level gauges, among others. There are also level gauges that operate using the magnetostrictive effect. (5) Nuclear radiation level gauge: It operates on the principle that the intensity of nuclear radiation decreases as it passes through a material layer, depending on the thickness of that layer. Gamma rays are currently the most widely used. (6) Acoustic property meters: As changes in liquid level cause variations in acoustic impedance, as well as differences in the obstruction of sound waves and their reflection distances, detecting these changes allows for the determination of the liquid level. Therefore, acoustic level gauges can be classified into acoustic interruption type, reflection type, and damping type based on their working principles. (7) Optical analog instrument