Method for manufacturing rigid tubular pipes having double casing, and facility dedicated to manufacture of said pipes

A method of manufacturing a rigid tubular pipe having a double casing for transporting hydrocarbons, the method comprising:

• providing an internal rigid tube and an external rigid tube wherein the internal tube is to be engaged in the external tube;
• providing a holding frame for holding an inlet end of the external rigid tube;
• providing an apron equipped with an activatable grasping device for grasping the rigid internal tube, wherein the apron is mobile in translation between a position near the holding frame and a position far from the holding frame;
• the method further comprising activating the grasping device and driving the apron toward the near position to engage the internal rigid tube in the interior of the external rigid tube and also leaving an annular space between the rigid tubes;
• then deactivating the grasping device to release the internal rigid tube while driving the apron in reverse toward the far position;
• providing heating cables for defining a lengthwise heating cable portion and applying the cable portion along the internal rigid tube when the apron is being driven in movement;
• and
• driving of the apron toward the near position, while the lengthwise heating cable portion that is applied along the internal rigid tube is engaged in the interior of the annular space.