Study On Near Net-shape Process Of The Pulley

Near net-shape technique of the pulley is an important plastic processingmethod in the future. Press forging and spin-forming process are advanced nearnet-shape technique. Press forging forming is composite of stamping and forging.The stamping process form the shape of parts，at the same time，Press forgingprocess form the partial volume，and then a large surface，different thickness andminimal rounded parts can be formed. The spin-forming of multi-wedge wheel slotsis specialty spinning，it is depend on the cycloid continuous radial feeding, and thenproducing local plastic deformation form the structure of the wheel groove. Theseprocesses not only effectively reduce the forming force and the molding step，butalso can improve the material utilization.This paper focuses on analyzing forging and Spin-forming process of thepulley parts，obtaining a feasible program. First，the structural characteristics offorging forming parts is analyzed，the shape and size of the parts is determined，thepress forging program combining of thickening process and local loading process isgotten. The structural characteristics of the spinning wheel groove is alsoanalyzed， three times spin-forming program is drawn after simplifying thereasonable model and determining the shape of the parts. Finite element models isestablished with the feasible program by DEFORM Software， and then finiteelement numerical simulation of the forming process is accomplished after settingreasonable parameters，the law of metal flow deformation is gotten，the distributionpattern of equivalent stress and strain in press forging and spinning process are alsoobtained.On the basis of numerical simulation of press forging and spin-formingprocesses，the paper analysis of the influence of different process parameters on theforming. In press forging，the rational mold fillet and die slope are propitious to thethickening forming，Partial load and low friction factor can reduce the forming load.In the flange，pre-rotary teeth and fine-rotary teeth forming of spinning，the rationalfeed speed and the low friction factor can make sure the wheel groove shapeaccuracy and the spin pressure low. These not only enrich near net-shape theory ofthe pulley，but also play a guiding role on the actual production.