Temperature-based method for determination of feed increments in crankshaft grinding

The design of a crankshaft-grinding cycle involves determining the radial infeed and axial infeed in each feed increment. A new method for determination of feed increments is developed to increase productivity while avoiding thermal damage. Analyses of the geometry, kinematics and specific-energy characteristic are made to estimate the feed-dependent distribution of maximum surface temperature along the wheel profile. It is discovered that there are two temperature maxima in the grinding zone when feeding both axially and radially. Therefore, the developed method determines the infeeds such that a predetermined burn threshold is matched in these two critical points. The new technology is validated by measurements of Barkhausen noise and residual stress. A comparison is made between the temperature-based method and the radial-plunge method previously used in production. The comparison indicates that lower cycle times are attainable with less risk of thermal damage. Results for material-removal rate and maximum surface temperature are also presented.