How to solve the drift of deep hole machining?

In the process of deep hole machining, due to the symmetry error of the two cutting edges of the drill and the inconsistency of sharpness, etc., it will cause the drift of the hole position during the drilling process. Under normal circumstances, it is difficult to control the drift value of 100mm within 0.1mm. Generally, the more demanding holes will be reamed after drilling. Reaming can control the diameter accuracy of the hole and improve the surface quality. But it cannot correct the drift caused by drilling.

In order to solve this problem, we broke the conventional thinking and believed that although the drift during drilling is unavoidable, the coaxiality requirement can still be ensured by adapting the outer circle to the inner hole. The specific process steps of deep hole machining hole position drift solution are:

(1) Blanking, leave a margin of 2mm for the total length.

(2) The left end of the car is exposed to light, and the outer circle of the rough car is φ35.5mm.

(3) Clamp the outer circle that has been rough-turned at the left end, and finish turning the right end face to ensure that the total length is 80±0.05 mm, and drill and ream through holes of φ4.9±0.05 mm.

(4) Remove the burrs at the two ends of the hole, two holes with φ4.9±0.05 mm, and the outer circle of φ34.9 mm is finely turned.

(5) Then process the remaining dimensions based on the outer circle of φ34.9 mm.

In this way, the φ4.9±0.05 mm hole is processed first, and then the other dimensions are processed on the basis of the φ4.9±0.05 mm hole, so that the drift error during the processing of the φ4.9±0.05 mm hole will be used in the subsequent processing Be corrected.