XTK138/5 five-axis process center can be especially used to process impeller, tyre mould and other complicated curved surface. Because turbine and worm technologic patent has been applied to it, the Process Center supplies a kind of turbine and worm backlash eliminator, being simple structure, easy to regulate, effectively to eliminate tooth clearance. Thus, the process can improve stability of gearing greatly. And also, the mill head used by five-axis process center, our patent, is concerned. Especially, a kind of AC-axis linkage mill head, which can realize linkage between A and C axis, two numerical control rotor linking, makes the face cutting edge of tools being vertical to the surface of the workpiece processed, in order to finish processing to elements of complicated curved surface. The patent number ZL200520034312.0, practical new patent, whose aim is to overcome some disadvantages in the present technology, supplies a kind of AC axis linkage mill head, which owns simple structure, good rigidity and high precision. Not only the process center can be used to process single workpiece for the small lot, but also is suitable for processing workpiece in mass production. Single pole structure is used for the lathe to finish five-axis process, therefore, the lathe can own maximal process area in condition of small floor area. The vertical stroke of RAM is 500mm, the gyration angle of mill head is 360 degree, swinging angle is between -90 and 90 degree, and the minimum swing radius is 150 millimeters. All of these provide metal cutting with especially large space. The bearable load of the swiveling table is 800 kilogram, which can clamp large and heavy workpieces. Servodrive and suitable servo-actualor has been applies to cutting feed to realize driving of axes. Meanwhile, the main shaft being variable-speed and RS232 interface also make functions of communication and control program for lathe working.