Radar Level Gauge Selection and Method
Radar level gauge selection is the 20th century, the mid-60s began to use the production of new technology products, is a use of microwave measurement technology, non-contact level measurement instruments. In the early days, it was mainly used for tanker tank level measurement.
Radar level gauge selection to overcome the previous use of mechanical contact level instrumentation of many shortcomings, such as the difficulty of cleaning and maintenance of inconvenience and so on. Subsequently, the radar level gauge was used for the measurement of the tank level on the shore and the measurement of the liquid level in the oil refining unit. With the continuous development of the petrochemical industry, the application of radar level gauge is increasingly widespread, especially the high-precision characteristics of the international measurement agencies have been certified to meet the material requirements of trade transfer materials.
Radar level gauge selection is the use of ultra-high frequency electromagnetic waves through the antenna to the measured liquid level of the container, when the electromagnetic wave reaches the surface after the reflection back, received by the same antenna and detect the difference between the emission wave and echo, Surface height. There are two kinds of radar level gauge selection mode, corresponding to two measurement principle, this approach is a "top-down" time travel measurement system, the measurement system through the antenna to a fixed bandwidth periodically to launch a fixed frequency The microwave pulse is received by the radar system after reflection of the material table.
Radar level gauge selection Antenna to receive the reflected microwave pulses and pass it to the electronic circuit, the microprocessor for processing this signal to identify the microwave pulse in the material table and the resulting echo, and thus calculate the liquid level, Will be measured liquid level distance is proportional to the time and then converted into electrical signals. Radar level meter selection of the microwave source is the x-band travel control oscillator, the antenna is the microwave frequency is linear modulation of the continuous wave, when the echo is received by the antenna, the microwave transmission frequency has changed. The frequency difference between the transmitted wave and the echo is proportional to the distance from the antenna to the liquid level, thereby calculating the liquid level.
Radar level gauge selection mainly by the electronic control unit and antenna, no moving parts, there is no mechanical wear, and mechanical parts of the liquid level measuring instruments compared to a longer service life, truly maintenance-free, can be used for most of the liquid Bit of the level of measurement, the issue of microwave can pass through the vacuum, do not need to transfer the media, by the atmosphere, steam, tank the impact of small fog. Radar level gauge selection using non-contact measurement, from the tank level density, concentration and other physical properties. Measuring range, strong anti-corrosion ability.
Easy to install, easy to maintain, high precision and high reliability, the digital level and the analogue output are adopted. It can be configured by single bus or multiple buses. The computer is connected. Radar level gauge selection of a wide range of selection of a first to consider the measured medium temperature, pressure, density, viscosity and corrosive properties such as the impact of its performance. Therefore, in the selection of a medium for a specific conditions under the characteristics of the appropriate antenna and the selected header.
Radar level gauge selection For small size, complex shape of the tank or the need to measure a variety of liquid interface applications, it is recommended to use guided-wave antenna radar level gauge; more complex measurement environment of the tank, such as media The use of non-contact radar level gauge selection, the liquid level gauge and the media does not touch, you can avoid the physical and chemical properties of the media affect its measurement accuracy or level gauge itself The damage.
Selection of radar level gauge with different measurement accuracy according to the purpose of media measurement. If only for internal cost accounting, accuracy requirements do not need to be too high; if used for trade handover, you must choose high-precision radar level gauge selection. In order to save investment, in the measurement accuracy to meet the needs of the premise of the choice of cost-effective products, due to the accuracy of radar level gauge selection, routine maintenance and service life directly affect the production efficiency and economic efficiency, so excellent quality and satisfaction After-sales service is essential for users.