Large-pipe-diameter combined type machine head device

The utility model belongs to the technical field of pipeline heat preservation, and particularly relates to a large-pipe-diameter combined type machine head device. A core rod expansion sleeve is arranged at the discharging end of an inner spiral body in the device, and a core rod is arranged at the end, away from the inner spiral body, of the core rod expansion sleeve; the outer side of the inner spiral body is sleeved with an outer spiral body, the discharging end of the outer spiral body is communicated with the discharging end of the inner spiral body, the outer side of the outer spiral body is sleeved with a die body, the outer side of the core rod expansion sleeve is sleeved with a mouth die expansion sleeve, and the outer side of the core rod is sleeved with a mouth die; a gap A with an unadjustable size exists between the core rod expansion sleeve and the mouth mold expansion sleeve, the gap A is communicated with the discharging end of the outer spiral body, the outer diameter of the gap A is gradual