Tubular body making device and tubular body making method

The invention relates to a tubular body making device which can change the internal diameter of a made tubular body without changing a cooling part. The tubular body making device comprises an extrusion part extruding melted resin materials downwards in a tubular way through a die; a drawing part drawing the tubular resin materials extruded from the die through the extrusion part; a cooling part having a conical face with a reducing diameter downwards and making the inner peripheral faces of the resin materials drawn from the drawing part contact wih the conical face so as to cool the resin materials; and a moving mechanism making the cooling part move vertically and changing the contact position of the cooling part conical face relative to the inner peripheral faces of the resin materials.