Process Research Of High Precision Turning For Small Dimension Inner Sphere

The yield of industrial sewing machine and its parts is very large. Most of these manufactures are joint ventures or exclusively foreign-owned enterprises. Their products are partly sold in the domestic market, and partly sold abroad. Compare with the same products from foreign countries, ours are in a very low quality, because of the machining process is so complicated that our manufacturers can not deal with them easily. So our products have low capability in the international competition, and they are sold only for a very low price: 1/6-1/3 compared with Japanese products.When the paper began, gathered materials indicated that, nowadays most researchers concentrated their attention on how to get ultra precision surfaces, on the machining of tiny dimension parts, and on machining processes just in general machining fields. But a high precision machining for some kind of special products is just a blank. In this field, the dimension maybe several millimeters to more or less a dozen, quality requirements maybe IT2-IT6, surface roughness maybe R_a0.2 or even lower. It seems nothing special when it is judged only from these figures. Actually, their dimension and the large run machining cost limit many machining methods. It is very worthful to work a way out for this kind of machining, to figure out the conflict between the precision and the cost.This paper studies processes of high precision turning for small dimension and complex inner-surface, based on experiments of small inner sphere turning. It analyses some factors which affect the machining precision and the surface roughness. It also brings forward requirements to the equipments and suggests out some conceivable processes. And, it shows a furnishment's design for the machining. At last, it discusses the results of the experiments.