A grinding process method of solid end mills groove with segmented unequal helical angles by cutting edges offset and interference

Solid end mills with variable helical angles within a certain range can effectively mitigate cutting vibration and enhance the machining quality. However, the grinding process for these helical grooves is complex, and the existing disclosed process method cannot grind those helical grooves accurately. This study proposes a two-pass grinding method for the helical groove with variable helical angles. First, a cutting edge model with variable helical angles is established by edge offset to guide the grinding process. Second, to ensure the required cross-section parameters while avoiding overcutting and edge discontinuity, a novel optimization algorithm for determining the grinding wheel posture, and calculation rules of related process parameters for the two-pass grinding process are proposed. Finally, the verification is conducted and the results show that the maximum relative error of cross-section parameters is 1.254 % in simulation machining, which indicates the theoretical modeling of posture optimization and cutting edge are correct, and the two-pass grinding process is effective. Furthermore, this approach can be extended to grinding other complex structures with helical grooves.