Furnace top ignition manhole structure of blast furnace

The blast furnace top ignition manhole structure is characterized in that an ignition hole is formed in the blast furnace top and selectively covers the ignition hole through a sealing cover, one end of the sealing cover is hinged to the outer side of the ignition hole through a hinge piece, the sealing cover comprises a first telescopic component and a locking assembly, and the first telescopic component comprises a fixed part and a telescopic part connected with the fixed part; the fixing part is hinged to the cross beam, the telescopic part is hinged to the sealing cover, the telescopic part contracts to drive the sealing cover to open the ignition hole, the telescopic part extends to drive the sealing cover to cover the ignition hole, a first locking hole is formed in the sealing cover, the first locking hole is right opposite to the hinge piece, and a second locking hole is formed in the side wall of the ignition hole in a penetrating mode. The locking assembly is arranged on the outer side of the igniti