This invention relates to the connection of thin wall stainless steel tubes which are sleeved with internal screw nuts and matched external screw lead coil inner holes separately with vertical turned-edges at the tube ends in which the former is mounted with a packing washer and an inner expanded packing gland of complete stainless steel for the latter between the two turned edges, the packing gland is composed of two taper tubes and a base connecting with double seal loops or a seal ring and a taper tube. The turned edge and washer are used for the former to ensure roundness of the port to bear the pressure for over 10 MPa suiting tube connection of shorter than 50mm and for the latter, tubes guarantee packing reliability of thin wall large tubes of over 50mm. |