Combined core rod capable of being rapidly replaced in pipe mold

The utility model discloses a combined core rod capable of being quickly replaced in a pipe mold, and relates to the technical field of pipe extrusion. Comprising a core rod main body positioned in a mouth mold and a core rod head for determining the wall thickness of a pipe, an internal thread groove is formed in the end of the core rod body, an external thread connector used for being matched with the internal thread groove is arranged at the end of the core rod head, an annular groove is formed in the outer side of the end of the core rod body, a sealing sleeve matched with the annular groove is fixedly connected to the end of the core rod head, and the annular groove is sleeved with the sealing sleeve. The sealing sleeve is in interference fit with the annular groove, a chamfer facilitating guiding the sealing sleeve into the annular groove is arranged on the side, close to the core rod head, of the annular groove, and a gap is formed between the side, away from the core rod head, of the annular groove an