With CONGAUGE LB 6755, the initial shell forming can be controlled more effectively because now the actual liquid steel level in the mold is known. This information allows to set up a closed control loop for the automation of the powder feeding system. This makes CONGAUGE LB 6755 a compact Industrie 4.0-application capable of ensuring a constant flux powder level throughout the casting campaign. As a result, the new sensor helps to significantly improve the metallurgical properties of the final product.
In order to achieve a uniform casting behavior in the mold and optimal product quality, both the level of the liquid steel in the mold and the thickness of the flux powder covering the steel must be controlled with greatest accuracy in continuous casting plants. The inflow of steel into the mold is controlled via measurement of the liquid steel level (meniscus). For a stable continuous casting process it is essential that this measurement is reliable, correct and that it provides the results instantly. The flux powder serves many purposes: It protects the liquid steel against oxidation and, in the form of molten slag, it serves as lubricant between the solidified steel shell and the mold, provides thermal insulation of the meniscus and makes for uniform heat exchange between the steel and the mold. Care has to be taken that the flux powder melts appropriately and in sufficient amount. Otherwise the consequences may be severe casting defects or even the need to abort the casting process.
Conventional sensors used so far in mold level gauges have only been able to measure either the level of the liquid steel in the mold or a mixed signal as a combination of the steel and the powder levels in the mold. Measuring both levels separately used to require two independent measuring techniques working on different physical principles. The solutions involving two separate devices, however, entail high costs, increase the maintenance effort and make the evaluation of the measured results a rather cumbersome procedure. The newly developed CONGAUGE LB 6755 sensor solves exactly this problem as it combines both level measurements within one unit. In addition to new plants, the sensor can just as well be retrofitted to existing casting plants. Particularly producers of high-grade steels will benefit from this new development.