There are many types of liquid level measuring instruments, and the most suitable measuring instrument can only be selected based on the process medium and its operating conditions, combined with the operating principle of the instrument. The types of commonly used level gauges are as follows:
1、 Magnetic flap level gauge
Magnetic flap level gauge is also known as magnetic column level gauge. Its structure is mainly designed and produced based on the principles of buoyancy and magnetic force. The position of a float with a magnet (referred to as a magnetic float) in the measured medium is affected by the effect of buoyancy. The change in liquid level leads to a change in the position of the magnetic float, and the static and magnetic coupling between the magnetic float and the magnetic turnover column (also known as the magnetic turnover plate) causes the magnetic turnover column to flip at a certain angle (the outer surface of the magnetic turnover column is coated with different colors), thereby reflecting the situation of the liquid level in the container.
2、 Magnetic float level gauge (level switch)
The structure of a magnetic float level gauge (level switch) is mainly designed and produced based on the principles of buoyancy and static magnetic field. The position of a floating ball with a magnet (referred to as a floating ball) in the measured medium is affected by the effect of buoyancy: changes in the liquid level lead to changes in the position of the magnetic float. The magnet in the float ball and the sensor (magnetic spring switch) act to change the number of components (such as fixed resistance) connected in series to the circuit, thereby changing the electrical quantity of the instrument circuit system. That is, the change in the position of the magnetic float causes a change in the electrical quantity. The liquid level in the container is reflected by detecting changes in electrical quantities.
3、 Explosion-proof float level switch
Explosion-proof float level switch, also known as explosion-proof float level controller. A liquid level control instrument specially designed and manufactured for use in explosive environments. This product is designed based on the principle of buoyancy and lever. When the liquid level in the container changes, the position of the float ball will change with the change of the liquid level. This displacement of the float ball will act on the microswitch through the lever, and then the microswitch will generate a switching signal.
4、 Glass plate level gauge
This level gauge is designed based on the principle of a communicator. The liquid path composed of a glass plate and the main body of the level gauge is connected to the container under test through a connecting pipe flange or tapered pipe thread to form a communicator. The liquid level is the same as the liquid level in the container when observed through the glass plate, that is, the liquid level height. The needle valves at both ends of the level gauge not only serve as stop valves, but also have a check valve function inside the steel ball. When the level gauge is accidentally damaged or leaked, the steel ball can automatically close the liquid channel under the pressure of the medium, preventing a large amount of liquid from flowing out for safe maintenance. The liquid level gauge can achieve functions such as corrosion prevention, heat preservation, frost prevention, lighting, etc. by changing the information of the parts or adding some auxiliary components.
5、 Glass tube level gauge
The liquid level gauge is a liquid path composed of glass tubes designed based on the principle of communicators. The passage is connected to the container under test through a connecting flange or tapered pipe thread to form a communicator, and the liquid level is observed to be the same as the liquid level in the container through a glass tube, that is, the liquid level height. The tubular level gauge mainly consists of glass tubes, maintenance sleeves, upper and lower valves, and connecting flanges (or threads). The function of anti-corrosion or thermal insulation can be achieved by changing the information of parts or adding some auxiliary components to the level gauge.
6、 Steel tape level gauge
Steel tape level gauge is a traditional level gauge. Designed and manufactured using the principle of mechanical balance, it consists of a liquid level detection device, a high-precision displacement transmission system, a constant force device, a display device, a transmitter device, and other peripherals.
7、 Heavy hammer detection level gauge
The heavy hammer detection level gauge is designed and produced based on the principle of mechanical balance. When the steel belt is immersed and floating in a certain position in the liquid and stationary, the gravity exerted on the float, steel wire rope (or steel belt), the weight and pointer, the buoyancy exerted on the steel belt by the liquid, and the system friction force are in a balanced state.
8、 Ultrasonic level meter
The working principle of this product: It is to transmit energy waves through a device that can transmit energy waves (usually pulse signals). The energy waves are reflected by obstacles, and a receiving device receives the reflected signal. The level change is determined by measuring the time difference of the energy wave movement process. Microwave signals are processed by electronic devices and ultimately converted into electrical signals related to material levels. The primary probe emits an ultrasonic pulse signal to the surface of the measured medium, and the ultrasonic wave is reflected when encountering the measured medium (obstacle) during transmission. The reflected ultrasonic signal is detected by an electronic module and processed through dedicated software. The time difference between the emitted ultrasonic wave and the echo is analyzed. Combining the transmission speed of the ultrasonic wave, the path of the ultrasonic wave propagation can be accurately calculated, thereby reflecting the level of the object.
Intelligent radar level meter
Intelligent radar level meter is a microwave level meter, an application of microwave (radar) positioning technology. Energy waves are emitted through a device that can emit energy waves (typically pulse signals). Energy waves are reflected by obstacles, and a receiving device receives the reflected signal. The level change is determined by measuring the time difference of the energy wave movement process. Microwave signals are processed by electronic devices and ultimately converted into electrical signals related to material levels.
10、 Guided wave radar level meter
Guided wave radar level meter is a microwave level meter, an application of microwave (radar) positioning technology. Energy waves are emitted through a device that can emit energy waves (typically pulse signals). Energy waves are transmitted in a waveguide, and they are reflected by obstacles. The reflected energy waves are transmitted from the waveguide to the receiving device, which then receives the reflected signal. The level change is determined by measuring the time difference of the energy wave movement process. Microwave signals are processed by electronic devices and eventually converted into electrical signals related to material levels.
11、 Capacitive level meter
The measurement principle of a capacitive level meter is that the oscillation frequency of an oscillating circuit is related to the capacitance value. Changes in the level of material cause changes in the system capacitance, which in turn changes the oscillation frequency of the oscillating circuit. The oscillating circuit in the sensor can convert the capacitance change caused by the material level change into a frequency change, and send it to the electronic module. After calculation, analysis, and processing, it can be converted into engineering quantities for display, thereby achieving continuous measurement of the material level.
12、 RF admittance level controller
Radio frequency admittance level controller is a new type of level measuring instrument designed and manufactured using radio frequency admittance level control technology. RF admittance measurement technology is simply a method of measuring the admittance of a system using high-frequency current measurements. Point based RF admittance technology is different from capacitive technology in that it uses a three terminal technology to diversify the measurement parameters. Due to the introduction of measurement parameters other than capacitance, especially resistance parameters, radio frequency admittance technology improves the signal-to-noise ratio of the instrument measurement signal, greatly improving the resolution, accuracy, and reliability of the instrument; The diversity of measurement parameters has also greatly expanded the reliable application field of instruments. A level control technology that makes the product better resistant to hanging (the material adhered to by the sensor is called hanging) performance, more reliable operation, more accurate measurement, and wider applicability.
13、 Tuning fork level controller
The tuning fork level controller is a new type of level switch. The sensing rod base of a tuning fork level switch is designed and fabricated using the principle of tuning fork vibration. The tuning fork rod is driven by a piezoelectric wafer, and another piezoelectric wafer receives the vibration signal, allowing the vibration signal to circulate and causing the sensing rod to resonate. When the material comes into contact with the sensing rod, the vibration signal gradually decreases until resonance stops, and the control circuit outputs an electrical contact signal. Due to the natural principle that the sensitivity of the sensing rod decreases sequentially from the front end to the rear seat, no error signal will occur when materials in the tank and around the barrel accumulate upward, touching the sensing rod base (rear) or discharging.
14、 Magnetostrictive level meter
The working principle of the magnetostrictive liquid level sensor: An initial pulse occurs in the electronic circuit in the electronic compartment. When the initial pulse is transmitted in the waveguide wire, a rotating magnetic field advancing in the direction of the waveguide wire occurs. When this magnetic field meets the permanent magnetic field in the magnetic ring or floating ball, the magnetostrictive effect occurs, causing the waveguide wire to twist, This twisting is sensed by the energy pickup installed in the electronic chamber and converted into corresponding current pulses. The time difference between the two pulses is calculated through the electronic circuit, and the measured displacement and liquid level can be accurately measured.
Post time: 22-03-23