The length of main beam is 105m. To make the landscape orientation of main beam more firm by increasing two saddles in the middle part. Design the legs by stiffness and flexible steel tube. There is reinforcing steel bar in the tube. The legs are firm and the surface of windward is small. There are many safe establishments as frequency conversion control, correct deflection system, wheel side detention and so on. There is overhaul hoist on the saddle and elevator on the stiffness leg.