Crankshaft machining method and special tool for crankshaft machining

The invention relates to a crankshaft machining method and a special tool for crankshaft machining, and belongs to the technical field of machining. The method includes: producing the special tool and performing rough machining; finishing two ends of a crankshaft by positioning through basic central holes made at the ends of the crankshaft; covering the two ends of the crankshaft with end covers; limiting relative angular positions of the end covers by a positioning former; fixing the end covers; positioning through corresponding eccentric central holes of the end covers; and machining front and rear corresponding eccentric segments of the crankshaft. The simple end cover tools are used for positioning, so that the technical problems that the crankshaft with the ends unavailable for central holes is difficult to clamp and low in positioning precision are solved ingeniously, no special machining equipment is needed, and the efficient high-precision machining method is provided for machining of the crankshafts, especially the crankshaft with a splined journal and small ends.