Thread cutting machine for sleeve

The utility model discloses a thread cutting machine for sleeves, which comprises a shaft core of a machine tool making reciprocating movement, an inner support which is used for supporting processed steel tubes and is composed of an inner supporting claw and an inclined sliding block, a core sleeve of the inner support, which is sheathed on the exterior of the core shaft of the machine tool and is used for fixing the inner support, and a compression spring. The inner supporting claw forms a staircase-shaped structure, the end face of the high end of the supporting claw is a supporting face for supporting the processed steel tubes. And the end face of the short end is a spring supporting face. The bottom face commonly shared by the high end and the short end is an inclined face which keeps sliding fit with the inclined sliding block. Because the utility model uses the structure, the cross-sectional area of the inner support of the thread cutting machine for sleeves is large, and the support forms double-row support. As a consequence, the utility model enhances supporting stability of inner holes of the steel tubes and raises thread machining quality and production efficiency. The utility model has the advantages of simple and convenient machining and strong process.