For the deep hole machining of slender shaft, the key point is the concentricity between the hole and the outer diameter. From the analysis of the part structure, it is not feasible to process deep holes in one clamping, so it is more reasonable to use the processing method of turning over and secondary clamping in one clamp and one support. The special damping turning tool bar is used to finish the inner hole, and the corresponding processing parameters are studied to ensure that the roughness is within ra3.2.
(1) adopt the secondary clamping method of turning over with one clip and one support to determine the alignment datum of 3 places evenly distributed on the outer circle, align and record the data. After turning over and clamping, align with the same alignment datum of 3 places to ensure that the alignment accuracy is not lower than that before turning over.
(2) adopt φ Finish machining the vibration damping turning tool bar, control the feed rate at the end of the finishing process, and observe the chip state through the test. In case of chaotic chips and bad chip breaking, adjust the chip parameters in time, so as to ensure the machining effect of the vibration damping turning tool bar, and the machining length on each side shall be greater than L / 2. See table for the test results of inner hole processing parameters.
| Cutting speed, m / min | Feed rate, mm / min | Cutting capacity, mm | Blade material |
| 130 | 0.2 | 0.15 | KCU10 |
(3) auxiliary control measures: the inner hole grinding device grinds the inner hole, and the effective length of the device is 1738mm, which can meet the requirements of deep hole grinding.