Development of Self-braking Nozzle for Steel Slab Continuous Casting Process

摘要

The Submerged Entry Nozzle (SEN) is used to pour molten steel from the tundish into the mold during steel continuous casting process. The nozzle is a one of the few control parameters that is relatively inexpensive to change, yet has a profound influence on the flow pattern and thus on quality. Nozzle parameters include bore size, port angle and opening size, nozzle wall thickness, port shape (round vs square vs oval), number of ports (bifurcated vs multiport), and nozzle bottom design (well vs. flat vs. sloped), and submergence depth. Both too large and too small submergence depth increases problems with longitudinal cracks and transverse depressions. [4] However, there are demands for the improvement of the SEN structure to achieve a more desirable flow pattern in the mold. There are several new techniques at SEN reported to improve the fluid flow pattern and inclusion removal for the slab continuous casting process, such as swirl nozzle, annular step nozzle, multiports nozzle, oval offset bore throttle plate, and "MOGUL" Lined SEN.