Ring-back type spiral cooling conveyor

The invention discloses a loopback type spiral cooling conveyor which comprises an inner ring flow channel, an outer ring flow channel, a butt joint channel, a feeding flow channel and a discharging flow channel, the inner ring flow channel is of an ascending spiral structure, the outer ring flow channel is of a descending spiral structure, the inner ring flow channel is coaxially arranged on the inner side of the outer ring flow channel in a sleeved mode, and the butt joint channel is arranged between the inner ring flow channel and the outer ring flow channel. The top end of the inner ring flow channel is horizontally connected with the top end of the outer ring flow channel through a butt joint channel, the bottom end of the inner ring flow channel is horizontally in butt joint with the feeding flow channel, and the bottom end of the outer ring flow channel is horizontally in butt joint with the discharging flow channel. By means of the mode, the loopback type spiral cooling conveyor not only can achieve s