Through shaft assembly device

The utility model discloses a through shaft assembly device for a crane. The through shaft assembly device comprises a support plate (1), a connection rod (2) penetrating through the support plate (1) transversely, at least two large bolts (4) and a wrenching part. The at least two large bolts penetrating through the support plate (1) transversely are matched with the support plate (1) and driven by the wrenching part to be wrenched. A fastener is arranged at one end of the connection rod (2) to fixedly connect a through shaft to be assembled with the connection rod (2). The through shaft assembly device further comprises a detachable location unit to fix the relative position of the connection rod (2) and the support plate (1). According to the through shaft assembly device, the through shaft is moved by the acting force between the at least two large bolts (4) and a rotary table, too much human input is not needed in the through shaft assembly process, and accordingly, the assembly efficiency and the assembly accuracy are improved.