... electric control system. Xkd21 series CNC gantry Boring & Milling machine is of double-column beam gantry lifting structure and consists ... machine bed, the workbench, the columns, the beam, the slide carriage box, the headstock, the ram, the milling head, the accessory ... adopted for the X-axis of the gantry boring and milling machine series, ensuring minimum friction coefficient, easy lubrication, the ...