Production process and damage mechanism of tundish sizing nozzle
The zirconium sizing nozzle is used as the key refractory material for billet continuous casting, which controls the flow of molten steel, determines the drawing speed of the billet in continuous casting, and is a necessary condition to ensure the normal operation of continuous casting. In addition to cracking, blockage and falling off of the sizing nozzle, it is also required that the diameter expansion speed should not be too fast to meet the requirements of long-term casting. Damage to the sizing nozzle . The damage process of the oxidized sizing nozzle is a complex physical and chemical effect of its interaction with steel slag and molten steel at high temperatures. The specific damage mechanism is divided into two categories: (1) Physical damage: During the use of the sizing nozzle, due to the large temperature difference between before and after pouring steel (the pouring temperature of the steel is 1540C, uneven heating, a huge thermal stress is generated ...