QTZ31.5(TC4207)is the horizontal jib frame, trolleying structure, slew on the top tower crane. It adopts the double wire winding electromotor series resistance velocity modulation. And the operating performance is reliable. The tower crane foundation may be press heavily-like or fixed type, energy conservation and environmental protection. This machine all necessary select the domestic famous brand product, the main electrical part is selected from imported completely, the safety device is reliable. It is widely adapted in each kind of large-scale architectural construction.