QUY50 Crawler Crane is designed and developed independently in absorption of foreign advanced technology and combined with China domestic work conditions. It features hydraulic drive, full swing and lattice boom, and also the first one adoption of pilot proportional control in China domestic crawler cranes. This crane is easy operation, stable travel and reasonable arrangement in structure. The maximum lifting capacity is 50t, boom length 13m~52m, jib length 9.15m~15.25m. This crane is suitable for lifting and installation job in construction site, mine, factory and dockside. Optional mechanical grab is available for earth moving and stacking work.