2.The cage consists of a gearbox, a seamless tube hollow spindle, a winch, a wire tray frame and a pneumatic brake device. There are 48 synchronous tubes arranged in the main shaft of the second section of the 36 disc cage, and there are 72 steel wire preconditioning devices before the cage. Each section of the main engine is made of a seamless tube hollow spindle through the support of the front support, which is very rigid, so that the beats are small and the speed of the cage can be improved. The axle center line of the wire tray frame and the main shaft center line are parallel to each other. The back of the winch is equipped with a gear back torsion mechanism, and the back torsion is realized by this mechanism.