&Three dimensional drill is mainly used for three-dimensional drilling processing of large-size H-beam or box girder. It adopts the method of fixed gantry moving, with high processing efficiency and stable precision, and can be widely used in construction, bridge, iron tower and other industries. The three-dimensional drill is mainly composed of bed, gantry, headstock, electrical control system, hydraulic system, cooling chip removal system and detection system. The machine tool adopts the form of gantry moving and worktable fixed, which can reduce the length of bed and save the floor area. The gantry motion (x-axis) is guided by linear roller guide, driven by AC servo motor and low backlash rack and pinion pair. The movement (U, V, w) of the slide board on the crossbeam and two pillars of the gantry is guided by linear ball guide, driven by AC servo motor and lead screw. The feed motion of each drilling head (axis 1,2,3) is guided by linear ball guide, driven by AC servo motor and lead screw. The spindle box of CNC 3D drilling adopts the CNC feed drilling power head produced by our company. There is a flat chain chip conveyor at the lower part of the machine tool, and a water pump and a cooling liquid filtering and circulating device are installed on the chip conveyor. The hydraulic system is mainly used for the positioning and locking of x-axis and the balance of power heads on both sides. The CNC three-dimensional drilling machine is controlled by PLC and equipped with upper computer. The workpiece is input and stored by computer, so it is easy to operate.