U.S. Steel Serbia primarily produces sheet products, including tin mill and galvanized products. The production process of cold sheet rolls involves various materials; each contributes differently to the final product's quality. The company strives for continuous improvement of its products' quality and therefore invests greatly in top of the line instrumentation throughout the plant.
The company sought ultrasonic level measurement gauges to monitor rust preventive oil and diluted HCL in three tanks.
Rust preventive oil provides a film of oil for rust protection as well as protection against wrap to wrap gouging during handling and further processing of the steel sheets in the pickle line. The oil is stored in tanks prior its usage in the pickle line. To keep the oil in a liquefied state the tank is warmed to an average temperature of 50C (122F). This temperature creates a warm and humid environment inside the tank which can often cause condensation around the ultrasonic sensor resulting inaccurate measurement results of the oil level.
Hydrochloric Acid (HCL) creates a chemical reaction that removes the surface oxide from the steel strip. Although the HCL solution that the plant uses is diluted, the environment inside the tank is highly corrosive. This kind of corrosive environment requires a durable ultrasonic sensor that will be able to properly function and won't wear in time.