Machining method for thin-wall shaft sleeve with two ends supported and middle suspended

The invention discloses a machining method for a thin-wall shaft sleeve with the two ends supported and the middle suspended. The machining method comprises the following steps of step 1, alignment, wherein both the runout of the front journal and the runout of the rear journal of an alignment rotor are smaller than 0.01 millimeter; step 2, rough turning, wherein rough turning is carried out on the excircle of a bush, and the single edge margin ranges from 0.10 millimeter to 0.15 millimeter; step 3, finish turning, wherein both the runout of the front journal and the runout of the rear journalof an alignment rotor are smaller than 0.01 millimeter, finish turning is carried out on the excircle of the bush, and the single edge margin of the part with the minimum diameter is 0.015 millimeter; step 4, chamfering, wherein chamfering is carried out on the sharp edge of the bush for 0.2 millimeter to 0.4 millimeter; step 5, checking, wherein both the runout of the front journal and the runout of the rear journal of an alignment rotor are smaller than 0.01 millimeter; step 6, finish grinding, wherein grinding is carried out on the excircle of the bush to the upper deviation; and step 7, precision polishing, wherein the bush is polished with abrasive paper for metallograph to guarantee the dimensions and the roughness of Ra 0.8, and then machining is completed. By adopting the machining method for a thin-wall shaft sleeve, with the two ends supported and the middle suspended, made of difficult-to-machine materials, the problems that a bush is scraped during machining, and measurement errors are large are successfully solved, the percent of pass of machined bushes reaches 100%, the efficiency is improved by 50%, and in a word, the machining method for a thin-wall shaft sleeve with the two ends supported and the middle suspended is high in efficiency and cost performance.