Micro negative pressure welding repair method for flue gas pipeline leakage

The invention relates to the technical field of smelting flue gas pipeline repair welding, and aims to provide a flue gas pipeline leakage micro-negative pressure repair welding method which comprises the following steps: S1, manufacturing a pipeline leakage micro-negative pressure repair welding device which comprises a smoke hood, an adjusting ball valve and two sections of straight pipes, and mounting an air pipe on the side wall of the straight pipe positioned at the rear end of the adjusting ball valve, an adjusting valve is mounted on the air pipe; s2, the pipeline leakage micro-negative-pressure welding repair device is in butt joint with a flue gas pipeline, an adjusting ball valve and an adjusting valve are opened, and the surrounding environment is in a micro-negative-pressure state; s3, the section, close to the smoke pipeline, of the smoke hood is subjected to rapid welding repair; s4, after welding repair is completed, the adjusting ball valve and the adjusting valve are closed, and the straight