The traditional approach to level measurement in a pressurised vessel, such as a boiler, has been to use a conventional differential pressure (DP) transmitter with external water-filled ‘wet’ legs connecting both the high and low pressure sides of the transmitter to the drum. The use of DP transmitters for drum level is ideal because of their low cost, ease of installation and high reliability. However, the output of a conventional DP transmitter in this application will have inaccuracies caused by changes in static pressure, the densities of the water in each leg, and the densities of the steam and water in the drum.
The Foxboro solution
The Foxboro IMV31 density-compensated level transmitter provides a new approach to drum level measurement. While maintaining all the advantages of DP transmitters, it uses multiple measurements and on-board level calculations to provide a more accurate measurement. This eliminates the need to make similar level calculations in the control system.
The new instrument is based on Foxboro’s proven multivariable transmitter technology, which was originally developed for flow measurement. The heart of the device is its ability to conduct on-board level calculations based on multiple measurements and fluid density calculations. The transmitter has a pressure sensor and a differential pressure sensor, as well as two internal temperature sensors. It also has the ability to power and monitor an external RTD temperature sensor.
The transmitter continuously calculates the unique fluid densities, based on measured pressures and temperatures, and uses this information along with the DP measurement to calculate an accurate density-compensated liquid level. The densities of both the water and steam are calculated separately, based on the pressure measurement and vessel temperature. The transmitter has an RTD input and can also use the saturation stream table’s temperature corresponding to the measured vessel pressure in calculating water and steam densities.
Results
Regardless of the size of the drum and the saturation pressure, the IMV31 significantly improves the accuracy of drum level measurement over conventional DP transmitters and automatically provides dynamic compensation for varying pressures and temperatures.
Level measurement in oil storage VEGA Controls SA
Level Measurement & Control
Measuring the level of crude oil in storage is essential for safe and efficient operations. VEGA offers solutions that effectively address the challenges, ensuring precise and consistent level measurements in crude oil storage facilities. VEGA’s sensors offer reliable data on the volume, level and pressure of all types of media. Accurate level measurement is complicated by crude oil thermal expansion properties, particularly in lighter oil grades.
Read more...Cloud-based inventory management Endress+Hauser South Africa
Level Measurement & Control
Netilion is an award-winning cloud-based IIoT ecosystem designed for industrial processes. It connects the physical and digital worlds to send valuable information from the field straight to your phone, tablet or other device.
Read more...Smart solutions for tabletting VEGA Controls SA
Level Measurement & Control
The manufacturing of pharmaceuticals is considered to be one of the most challenging production environments. Pharmaceutical manufacturers across the globe have opted for VEGA sensors in their production facilities.
Read more...Magnetostrictive level transmitter WIKA Instruments
Level Measurement & Control
WIKA’s new model FLM-Tx-FLEX magnetostrictive level transmitter is used for high-accuracy, continuous level detection of liquids, including those with long insertion lengths.
Read more...Superhero vision for hazardous waste environmental control VEGA Controls SA
Level Measurement & Control
VEGA understands that in the world of hazardous waste management, ensuring both safety and efficiency is crucial. With the disposal of chemicals requiring conscientious attention to ethical and ecological standards, innovative solutions are mandatory. Among these solutions, non-contact level sensors emerge as a game changer, offering increased safety in environments laden with dangerous substances.
Read more...Copper mining powered by VEGA VEGA Controls SA
Level Measurement & Control
VEGA sensors are an integral part of the continuous monitoring and control systems across the board in mining and beneficiation processes. The robustness, reliability and precision of VEGA instruments make them a good choice for managing liquid levels and ensuring the smooth operation of the production process.
Read more...Cloud-based inventory management software Endress+Hauser South Africa
Level Measurement & Control
Netilion is an award-winning cloud-based IIoT ecosystem designed for industrial processes. It connects the physical and digital worlds to send valuable information from the field straight to your phone, tablet or other device.
Read more...Level sensing, conveyor control and grid resistors DRH Components
Editor's Choice Level Measurement & Control
DRH Components is a specialist electric component and systems supplier with a focus on the control of electric motors. As part of its wide variety of products, the company markets the entire Bindicator range. Bindicator manufactures sensors for dry bulk and liquid level measurement.
Read more...Level measurement under extreme plant processing conditions VEGA Controls SA
Level Measurement & Control
Level measurement in LNG and LPG processes is about answering the simple question: “How much product is in the tank?” However, obtaining an exact value is not easy. The products are often under pressure, cryogenic, and highly explosive. Sensors from Vega have been operating successfully in all stages of the LNG/LPG process for many years.
Read more...Grounding of hydrostatic level sensors WIKA Instruments
Level Measurement & Control
Hydrostatic level sensors are very often installed in outdoor applications, primarily in the water and wastewater industries. A good connection to ground is essential when installing hydrostatic level sensors, since no grounding or poor grounding can result in destruction or damage to the level sensor.
printer friendly version