Press-fitting connection structure for pipeline and refrigeration device

A press-fitting connection structure for pipeline, comprising a tubular-shaped connecting body for connecting pipes, wherein

• a first mounting groove and a second mounting groove are defined in an inner surface of the connecting body, arranged in sequence along an axial direction and spaced from each other,
• a sealing ring is mounted in the first mounting groove, a retaining ring is mounted in the second mounting groove, an axial position of the retaining ring is limited by the second mounting groove, a plurality of retaining teeth is provided on an inner surface of the retaining ring, and each of the plurality of retaining teeth comprises a tip end arranged toward an inner side,
• a protective ring is mounted at an end portion of the connecting body for guiding an installation of the one of the pipes into the connecting body, wherein an inner diameter of the protective ring is smaller than a diameter of a circle defined by the tip ends of the retaining teeth of the retaining ring,
• during press-fitting, the connecting body is mounted around and sealed with one of the pipes through the sealing ring, and the retaining teeth of the retaining ring are buried into a wall of the one of the pipes through the tip ends.