Special vertical and horizontal boring and milling machine for wind power bearing seat and machining process thereof

When the vertical and horizontal boring and milling machine special for the wind power bearing seat is used for machining a large-size workpiece, vertical end milling heads or transverse side milling heads are installed through a plurality of main shafts on a front portal frame and a rear portal frame on the two sides correspondingly, and the vertical end milling heads or the transverse side milling heads are arranged on the main shafts correspondingly; according to the large-size workpiece machining equipment, the end face and the side face of the upper half portion of a large-size workpiece to be machined are machined, the workpiece to be machined is turned over after the upper half portion is machined, the remaining half portion is machined, when the large-size workpiece is machined, the production and manufacturing cost of the large-size workpiece machining equipment can be effectively saved, the machining technological process of large-size workpiece machining is effectively simplified, and the machining