Stainless steel pipe welding cooling device and cooling welding method thereof

The stainless steel pipe welding cooling device is provided with a first blocking plate and a second blocking plate, the first blocking plate and the second blocking plate are connected and fixed through two or more long-strip-shaped connecting plates, one end of each connecting plate is welded and fixed to the first blocking plate, and the other end of each connecting plate is movably connected with the second blocking plate through a connecting piece. A leading-in mechanism is fixed to the center of the first blocking plate and comprises a fastening base and a rotating body, and an inlet pipeline and a discharge pipeline penetrate through the center of the rotating body to enter the first blocking plate. The device is located in the pipe fitting to be welded, argon enters the sealed space at the flow rate of 10 L/min-15 L/min, when the purity of the argon in the sealed space is not larger than 50 ppm, welding is carried out, cooling water is input into the sealed space after welding is carried out for 2-3 w