Slab scarfing apparatus and method for controlling the same

A slab scarfing apparatus comprising:

• an upper nozzle unit which comprises an upper surface nozzle which scarfs a corner portion of an upper surface of a slab and a first side nozzle which moves together with the upper surface nozzle while scarfing an upper corner portion of a side of the slab;
• a lower nozzle unit which comprises a lower surface nozzle unit which scarfs a corner portion of a lower surface of the slab and a second side nozzle which moves together with the lower surface nozzle while scarfing a lower corner portion of the side of the slab;
• a movement apparatus which moves the upper nozzle unit and the lower nozzle unit to be closer to or away from a corner portion of the slab;
• and
• a slag chamber which is installed to surround front areas of the upper nozzle unit and the lower nozzle unit which the slab enters and collects slag scattered by scarfing of the slab and a high pressure water injection apparatus disposed in a slag scattering area inside the slag chamber.

A slab scarfing apparatus comprising:

• an upper nozzle unit which comprises an upper surface nozzle which scarfs a corner portion of an upper surface of a slab and a first side nozzle which moves together with the upper surface nozzle while scarfing an upper corner portion of a side of the slab;
• a lower nozzle unit which comprises a lower surface nozzle unit which scarfs a corner portion of a lower surface of the slab and a second side nozzle which moves together with the lower surface nozzle while scarfing a lower corner portion of the side of the slab;
• a movement apparatus which moves the upper nozzle unit and the lower nozzle unit to be closer to or away from a corner portion of the slab;
• a correction device which corrects a posture of the slab on a transfer path before entering a scarfing area in which the upper nozzle unit and the lower nozzle unit are located;
• a width measuring sensor which measures a width of the slab to sense eccentricity of the slab which have passed through the correction device;
• an entry sensor which senses an entry of a fore end of the slab at a position before the scarfing area;
• a pinch roll which transfers the slab to the scarfing area in a clamped state after the entry of the slab;
• and
• a nozzle position sensor which senses elevated positions of the upper and lower nozzle units to prevent a collision of the slab and the upper and lower nozzle units.

A slab scarfing apparatus comprising:

• an upper nozzle unit which comprises an upper surface nozzle which scarfs a corner portion of an upper surface of a slab and a first side nozzle which moves together with the upper surface nozzle while scarfing an upper corner portion of a side of the slab;
• a lower nozzle unit which comprises a lower surface nozzle unit which scarfs a corner portion of a lower surface of the slab and a second side nozzle which moves together with the lower surface nozzle while scarfing a lower corner portion of the side of the slab;
• a movement apparatus which moves the upper nozzle unit and the lower nozzle unit to be closer to or away from a corner portion of the slab;
• a flexure sensor which measures flexure of the slab on a transfer path before the scarfing area entering a scarfing area where the upper nozzle unit and the lower nozzle unit are located;
• and
• a flexure correction device which corrects the flexure of the slab by spraying high pressure cooling water to the upper surface or the lower surface of the slab according to flexure information from the flexure sensor.