The technical requirements of non-standard machining are generally based on the function and working conditions of the shaft, and generally have the following items:

(a) Surface roughness of precision parts

Generally, the surface roughness of the shaft diameter coordinated with the transmission is Ra2.5~0.63μm, and the surface roughness of the supporting shaft diameter coordinated with the bearing is Ra0.63~0.16μm.

(b) Precision of the orientation of precision parts to each other

The azimuth accuracy of the processing of non-standard parts is mainly determined by the orientation and function of the shaft in the machine. Generally, it should be ensured that the shaft journal of the transmission part of the device is coaxial to the supporting shaft journal, otherwise it will affect the transmission accuracy of the transmission part (gear, etc.) and produce noise. For shafts with general accuracy, the radial runout of the cooperative shaft segment on the supporting journal is generally 0.01~0.03mm, and the high-precision shaft (such as the main shaft) is generally 0.001~0.005mm.

(c) Precision parts geometry accuracy

The geometric accuracy of shaft non-standard machining mainly refers to the roundness and cylindricity of shaft journal, outer cone, Morse cone hole, etc., and its tolerance should generally be restricted within the standard tolerance range. For the surface of the inner circle with higher precision, the allowable deviation should be marked on the drawing.

(d) Non-standard parts processing standard accuracy

In order to determine the orientation of the shaft, CNC machining generally requires a higher standard accuracy (IT5~IT7). The standard accuracy of the journal of the device transmission is generally low (IT6~IT9).

Precision parts centroid CNC lathe (centroid/slitter lathe) is a kind of CNC machine tool mainly used in shaft and non-standard shaft precision machining, non-standard machining it has a qualitative leap in processing power and processing accuracy than CNC lathe, because the use of dual-axis arrangement tools, greatly reducing the processing cycle time, By shortening the tool exchange time between the row tool and the opposite tool table, the stacking function of multiple tool tables, the moving and stacking function of the useful shaft of the threaded chips, and the indexing function of the direct spindle during the secondary processing, the empty travel time is shortened. The chip cutter is always processed at the clamping part of the spindle and the workpiece, ensuring that the accuracy of the processing remains unchanged. At present, the processing diameter of the shopping mall walking machine is 42mm, which has great advantages in the precision shaft processing market. This series of machine tools can be equipped with active feeding equipment, complete the full active production of a single machine tool, reduce labor costs and product defect rate. Non-standard parts machining is suitable for mass production of precision shaft parts.