Apparatus for forming a protecting duct with integrated inner and outer walls, and the duct formed thereby

An apparatus for forming a protecting duct with integrated inner and outer walls, comprising:

• an inner-wall dice for forming a semi-solid inner wall with molding resin,
• an outer-wall dice for forming a semi-solid, unshaped outer wall with molding resin around the outer circumferential surface of the semi-solid inner wall;
• and
• an outer-wall sizing machine which allows the outer wall to be shaped around the outer circumferential surface of the inner wall as the semi-solid inner wall and unshaped semi-solid outer wall pass through the machine,
• wherein a cylindrical sizing machine is located next to the inner-wall dice, which reduces the outer diameter of the inner wall to a desired length as it passes from the entry point, into which the semi-solid inner wall is introduced, to the end point, and a coolant flow path, through which the coolant is supplied from an external source, is formed within the inner-wall dice and the inner-wall sizing machine;
• wherein a guide support rod is installed, extending from the inner-wall dice to the inside of the outer-wall sizing machine in which an inner-wall guide supported by the guide support rod is installed at the position where the shaping occurs within the outer wall, and the semi-solid inner wall passes between the inner-wall guide and the outer wall being shaped for tight integration with the outer wall by means of pressurization;
• and
• wherein inside the outer-wall sizing machine is a cooling unit for cooling the inner wall and the protection duct integrated with the outer wall.