Rough machining method for partspan shroud of turbine blade

The present invention discloses a rough machining method for a partspan shroud of a turbine blade. The method comprises the following steps: (1) selecting a cutter which has a radius difference between a cutter bit and a cutter bar equal or greater than the depth of the reversing shaded side of the partspan shroud to be machined; and (2) creating a numerical control machining procedure of the partspan shroud according to the features of the partspan shroud and the selected cutter, and by controlling the gesture of the cutter, machining the sharp curved surface of the partspan shroud and the adapter position of the partspan shroud and the root of the blade profile by a chamfer of the cutter, where the small position of the cutter bar of the cutter avoids the interference part of the shaded side of the partspan shroud. The method uses a cutter to finish the rough machining of the profile and the bottom of the partspan shroud, makes margin for finish machining, and improves the machining quality. It does not need to replace the cutter and does not need supplemental machining. The ineffective cutting time (except feeding and relieving) is short. The load of the machine tool is uniform, and the cutting process is smooth. Therefore, the machining efficiency is greatly improved, and the difficulty and bottleneck of the shroud machining is efficiently overcome.