Manufacturing method of integral herringbone gear shaft

The invention discloses a manufacturing method of an integral herringbone gear shaft, which comprises the following steps that: material preparation: a center hole is drilled on one end of a work piece; primary machining; primary detection; heat treatment; secondary machining; secondary detection; rough milling; chamfering at the gear end; coating anti-carburizing layers on both ends of the herringbone gear shaft so that the depth of a carburized layer is 3.55 to 3.95mm, and quenching so as to enable the hardness of a gear part to reach HRC58 to 62, and to enable the hardness of the heart to reach HRC28 to 33; carrying out shoot peening on a gear surface; tertiary machining; gear shaping; external grinding; fine milling; and inspection. The manufacturing method of the integral herringbone gear shaft has the advantages of improving the bending strength of the gear root, reducing the manufacturing cost and improving the manufacturing precision.