Manufacturing device and process for inner pipe of double-layer cooling pipe

The invention discloses a manufacturing device and process for an inner pipe of a double-layer cooling pipe. The device mainly comprises magnetic bars, a pipe blank, two portal frames, a cross beam, guide rails, a preheating electrode, a welding electrode, a heat supplementing electrode, extrusion rollers, an infrared camera and the like. The two portal frames are connected through the cross beam. The cross beam is provided with the three sets of guide rails. The preheating electrode, the welding electrode and the heat supplementing electrode are sequentially mounted on the three sets of guide rails. The pipe blank to be welded is arranged below the cross beam. The magnetic bars are coaxially mounted in the pipe blank. The extrusion rollers are symmetrically mounted on the two sides of a point V of the pipe blank. The infrared camera (fixed to the portal frames) is arranged above the point V. The process comprises the specific steps of firstly, preheating a groove of the pipe blank through the preheating elec