CNC floor-type milling and boring machines and machining centers can be divided into two types according to different in intergrated headstock installed. i.e. machines with extended ram and machines with extended boring spindle. For the former type, CNC boring spindle is supplied inside ram to accomplish deep-hole drilling. The steel guide-ways provide the machine with high rigidity and retainability. They can be equipped with optional accessories such as CNC rotary worktable, facing head, right angle milling head and universal milling head, suitable for drilling, boring, reaming, turning, milling, threading etc. processes for large and middle-sized work-piece, in particular, they are the ideal equipments for machining large-sized work-pieces with deep-holes.