Dual-purpose facility of continuous hot-dip coating and continuous annealing

1. A dual-purpose facility of continuous hot-dip coating and continuous annealing which is configured so as to be switched between a continuous hot-dip coated material production line in which a steel strip annealed in an annealing furnace is immersed into a hot-dip coating bath and a continuous annealed material production line in which the steel strip bypasses the hot-dip coating bath and is guided out of the annealing furnace into an air outside the furnace, the dual-purpose facility comprising:

a gas discharge path that discharges atmosphere gas in the annealing furnace from a gas discharge port provided in an outlet side of the annealing furnace out of the annealing furnace;

a path opening and closing unit for opening and closing the gas discharge path; and

a cyclone that is disposed in the gas discharge path and removes metal fumes contained in the atmosphere gas by making the atmosphere gas have a rotational flow,

wherein the path opening and closing unit opens the gas discharge path when the dual-purpose facility is used as the continuous hot-dip coated material production line and closes the gas discharge path when the dual-purpose facility is used as the continuous annealed material production line.

2. The dual-purpose facility of continuous hot-dip coating and continuous annealing according to claim 1 , further comprising

a flow rate regulating unit that is disposed in the gas discharge path; and

a furnace pressure measuring unit for measuring a furnace pressure in the annealing furnace,

wherein a discharge amount of the atmosphere gas, which is discharged out of the annealing furnace through the gas discharge path when the dual-purpose facility is used as the continuous hot-dip coated material production line, is regulated by the flow rate regulating unit based on the furnace pressure which is measured by the furnace pressure measuring unit when the dual-purpose facility is used as the continuous annealed material production line.

3. The dual-purpose facility of continuous hot-dip coating and continuous annealing according to claim 1 or 2 , further comprising

a gas suction unit that is disposed in the gas discharge path, for suctioning the atmosphere gas in the annealing furnace, and for discharging the gas out of the annealing furnace.

4. The dual-purpose facility of continuous hot-dip coating and continuous annealing according to claim 3 ,

wherein the gas suction unit is an ejector.

5. A dual-purpose facility of continuous hot-dip coating and continuous annealing which is configured so as to be switched between a continuous hot-dip coated material production line in which a steel strip annealed in an annealing furnace is immersed into a hot-dip coating bath and a continuous annealed material production line in which the steel strip bypasses the hot-dip coating bath and is guided out of the annealing furnace into an air outside the furnace, the dual-purpose facility comprising:

a gas discharge path that discharges atmosphere gas in the annealing furnace from a gas discharge port provided in an outlet side of the annealing furnace out of the annealing furnace;

a path opening and closing unit for opening and closing the gas discharge path; and

a gas suction unit that is disposed in the gas discharge path, for suctioning the atmosphere gas in the annealing furnace, and for discharging the gas out of the annealing furnace,

wherein the path opening and closing unit opens the gas discharge path when the dual-purpose facility is used as the continuous hot-dip coated material production line and closes the gas discharge path when the dual-purpose facility is used as the continuous annealed material production line,

the gas suction unit is an ejector, and

the ejector suctions the atmosphere gas in the annealing furnace based on a negative pressure which is generated by a non-oxidizing gas supplied to the inner portion of the ejector.

6. The dual-purpose facility of continuous hot-dip coating and continuous annealing according to claim 5 ,

wherein the ejector is disposed to an upstream side of a flow rate regulating unit that is disposed in the gas discharge path.

7. The dual-purpose facility of continuous hot-dip coating and continuous annealing according to claim 1 ,

wherein the cyclone is disposed to an upstream side of a gas suction unit that is disposed in the gas discharge path.

8. The dual-purpose facility of continuous hot-dip coating and continuous annealing according to claim 5 , further comprising

a flow rate regulating unit that is disposed in the gas discharge path; and

a furnace pressure measuring unit for measuring a furnace pressure in the annealing furnace,

wherein a discharge amount of the atmosphere gas, which is discharged out of the annealing furnace through the gas discharge path when the dual-purpose facility is used as the continuous hot-dip coated material production line, is regulated by the flow rate regulating unit based on the furnace pressure which is measured by the furnace pressure measuring unit when the dual-purpose facility is used as the continuous annealed material production line.

9. The dual-purpose facility of continuous hot-dip coating and continuous annealing according to claim 6 , further comprising

a furnace pressure measuring unit for measuring a furnace pressure in the annealing furnace,

wherein a discharge amount of the atmosphere gas, which is discharged out of the annealing furnace through the gas discharge path when the dual-purpose facility is used as the continuous hot-dip coated material production line, is regulated by the flow rate regulating unit based on the furnace pressure which is measured by the furnace pressure measuring unit when the dual-purpose facility is used as the continuous annealed material production line.