Laddle Furnaces
Design
The Hot metal ladle shall be of circular design with all welded construction and reinforced by two stiffener rings with special reinforcement in the area of the trunnions. The bottom of the ladle shall be made of a single plate and shall be dished. The ladle shell and bottom shall be designed for a maximum operating condition of 4000C. After complete welding, the ladle shall be stress relieved.
Trunnion
The trunnion and trunnion plates of the ladle shall be made of forged steel of grade 20 C8 or 30 C8. The trunnion plate shall be annealed after forging and shall be ultrasonically tested for soundness. The forged trunnion pins are welded into the trunnion ring and into the ladle shell. Three ladle foot are welded to the ladle bottom to permit placing on ground floor. The trunnions shall be designed with a minimum factor of safety of 8. Suitable flange shall be welded inside the ladle for retaining the permanent refractory lining.
Tilting Mechanism
The ladle shall be provided with tilting mechanism outside the shell for tilting. A tilting device is provided at the ladle bottom which is designed so that the tilting hook to the crane can be engaged and/or disengaged without manual help. The flat ladle bottom is furnished with an opening for the base plate (by others) for fixing the slide gate.
Seats of suitable design shall be provided under the trunions for placing the ladle on the turret of the continuous casting machine, transfer car and ladle stand.
Vent holes shall be provided at suitable spacing on the shell and bottom plate. Ladle shell and Bottom plate are furnished with deOilsing holes so that humidity and Oils generated during drying of the new lining may escape. The de Oilsing holes (Ø10) shall be placed on a grid.
The ladle is equipped with one bayonet for fixing the porous plugs as well as the piping installation to the porous plugs.
Welding
All weld joints shall be full penetration double groove butt weld with backgauged roots and all butt joints shall be fully radiographed. Electrodes shall be selected in such a way that the strength of the welded joints shall not be less than that of the parent metal. All welds of the charging ladle are 100 % magnaflux-tested (MT). In addition all full penetration welds are 100 % ultrasonic.