Die design and experiment for forming the teeth of shafts by rolling

Combining the theory of wedge cross rolling(WCR) with forming gears by rolling,a method was proposed to form teeth simultaneously when rolling gear shafts.The method can not only realize the near net forming of gear shafts,but also improve the mechanical properties and service life of teeth.In the process of forming teeth by rolling,the feed was not continuous but intermittent,and workpieces were compelled to roll in free graduation under the rotation of dies.The calculation method and change law of die tooth pitch,the design of die tooth forms,the calculation method of the minimum feed at the first half circle and the law of feed change in each stage of rolling were presented on the basis of mathematical models and experiments.The rolling process was simulated by numerical software Deform-3D,with which the dies can be correctly designed.A toothed shaft with the module of the gear m=2,the number of teeth z=20 and the pressure angle a'=20° has been successfully formed with the H630 rolling tool.It is proved that forming teeth on gear shafts by wedge cross rolling is feasible.