OndoSense has developed a measurement system for the level monitoring of molten aluminum, steel or copper inside closed furnaces: The new OndoSense FurnaceProtect radar solution measures the fill level in closed melting, casting and holding furnaces from the outside through a small opening in the furnace lid of only ~50 mm. The radar system offers a measurement accuracy of up to 0.3 mm, even in the presence of dust, steam, smoke, vibrations and metal temperatures of up to 1600 °C.
Significant fluctuations in fill levels during the melting process do not affect the measurement precision or reliability. This is due to the unique combination of a high measurement rate (500 Hz) and smart filter algorithms inherent in OndoSense radar technology. The level monitoring system therefore consistently delivers error-free, highly accurate and rapid measurements, even in the presence of wave motion, bubble formation or other abrupt fill level fluctuations.
Easy integration & highest performance
Based on the OndoSense apex Level Line, the new OndoSense FurnaceProtect radar system not only enables higher productivity in the operation of melting, casting and holding furnaces: It also reduces energy costs, optimizes raw material usage and prevents furnace overfilling.
The new radar-based level measurement solution meets the highest requirements for heat, temperature or pressure resistance and can be integrated into melting or holding furnaces very easily. Thus, the OndoSense FurnaceProtect housing is simply mounted on the furnace lid, with the housing’s protective tube inserted through an opening in the lid measuring just ~50 mm.
The OndoSense FurnaceProtect radar solution is equipped with either an advanced Profinet interface or a proven analog current interface (4–20 mA). It also offers three digital switching outputs (PNP/NPN). The measurement range extends from 0.1 meters to 30 meters. The radar system features a webserver-based configuration software with pre-installed application profiles, ensuring simple and rapid sensor commissioning.
No calibration or radiation protection required
Until now, non-contact level measurement of molten aluminum or steel in closed melting furnaces was only possible using radiometric methods – which come with several drawbacks: Measurements involving radioactive isotopes are subject to strict regulatory approvals, extensive safety training, and rigorous radiation protection requirements. Furthermore, radiometric systems require frequent recalibration based on furnace wall thickness as well as the specific metal or alloy to ensure reliable readings. The new OndoSense FurnaceProtect radar solution eliminates these shortcomings.
Savings costs through determination of energy requirements
The OndoSense FurnaceProtect radar solution enables a more accurate measurement of the energy required for melting metal: "Precise level measurement within the melting furnace allows for a better estimate of the amount of metal inside. Consequently, the energy required to melt the metal can be determined more accurately. This saves energy costs and enables better planning of the melting process. It also helps avoid furnace overfilling – which leads to unnecessary raw material consumption, unplanned downtime, potential accidents, and high additional costs," explains Co-CEO Waltersbacher.
The level control in melting furnaces is required in particular for the recycling of scrap metal such as aluminum, steel or copper to determine exactly when the metal has fully melted. At the start of the melting process, the still solid metal scrap typically forms a pile in the center of the furnace, resulting in a lower level at the furnace rim. As the melting progresses, the level at the rim rises. Once the metal has completely melted, the level readings are uniform throughout.
