Machining tool and machining method for step long shaft

The invention relates to the technical field of turning in the technical field of machining and manufacturing, in particular to a machining tool and method for a stepped long shaft. According to the technical scheme, the stepped long shaft machining tool comprises a lathe, a tailstock is arranged on one side of the lathe, a main shaft is installed in the other side of the lathe, and a triangular chuck is fixedly installed at the output end of the main shaft; the middle of the main shaft is of a hollow structure, a conical hole is formed in the hollow part close to the left end of the main shaft, and first external threads are formed in the outer wall of the left end of the main shaft; the tool and the machining process have the beneficial effects that the tool and the machining process can be used for machining on a common lathe of 1000 mm, the universality of the used lathe is high, and due to the fact that the long shaft is located in the main shaft in the machining process, safety is enhanced; through the