The device has an extrusion device (1) extruding a pipe body (2) from a thermoplastic plastic. A calibrating device (8) i.e. laser boring device, calibrates the extruded body to a desired outer shape. A pre-cooling chamber (5) and a main cooling chamber (9) cool the extruded body by coolants. A boring device (7) attaches outlet openings for water in an area of dosing elements (4). An additional chamber (6) is arranged in the pre-cooling chamber. The main cooling chamber is arranged in the additional chamber. The calibrating device is inserted between the additional and main cooling chambers.
