Orifice chamfering cutter of mold cooling runner

The invention provides an orifice chamfering tool for a mold cooling runner, and belongs to the technical field of mold machining. The orifice chamfering tool solves the problems that an existing orifice chamfering tool for a mold cooling runner is low in machining precision and metal chippings remain. The orifice chamfering tool of the mold cooling runner comprises a tool cylinder and a tool bar, a tool bit is fixed to the lower end of the tool bar, a positioning head is fixed to the lower end face of the tool bit, a chip storage cavity is formed in the tool cylinder, a chip removal opening is formed in the side wall of the tool cylinder, an air inlet channel is formed in the tool bar, a plurality of air injection holes are formed in the positioning head, and a plurality of purging holes are formed in the tool bar. A switching head is further rotationally inserted into the positioning head, and when the switching head rotates to enable the air inlet channel and the air spraying hole to be disconnected, the s