Pipeline connecting structure

The utility model belongs to the technical field of pipeline connection, and discloses a pipeline connection structure which comprises a fixing ring fixedly sleeved on an elbow connection pipe, the fixing ring is screwed and fixed with the elbow connection pipe through threads, and the input end of the elbow connection pipe is fixedly connected with one end of a pressure vessel connection pipe in a sealing mode. A connecting groove is formed in the inner edge of the output end of the pressure vessel connecting pipe, the input end of the elbow connecting pipe protrudes out of the fixing ring, the outer surface of the output end of the elbow connecting pipe is sleeved with the sealing gasket, and the output end of the elbow connecting pipe is further sleeved with a connecting sleeve which is provided with a limiting end and an entering end. The connecting sleeve inlet end sleeves the outer side of the output end of the pressure vessel connecting pipe and is screwed and fixed with the output end of the pressure