portions on a first tube with the second enlarged portion near an end of the second tube a first shoulder is provided between the first enlarged portion and the main body of the first tube a second annular shoulder is provided at the junction between the first and second enlarged portions the end of the second tube slips into the first enlarged portion of the second tube and the second tube is then axially compressed so as to form an annular bead which acts against and is contained by the second enlarged portion of the first tube this axial compression provides both a mechanical interconnection so that the tubes will not axially separate despite fluid pressure or mechanical force and also provides a fluid tight seal at the annular bead and the second shoulder or second enlarged portion the foregoing abstract is merely a resume of one general application is not a complete discussion of all principles of operation or applications and is not to be construed as a limitation on the scope of the claimed subject matter application_number US 26349381 A description the fig1 5 show the succession of steps in the method of forming a tube joint 11 shown completed in fig5 except that it is not removed from first die means 13 which grip a first tube 15 and from second die means 14 which grip a second tube 16 the first die means 13 includes a pair of dies 13a and 13b shown in fig1 these may have generally semicylindrical cavities therein to be clamped on the first tube 15 the first die means 13 when closed as shown in fig1 has a first enlarged cavity 17 and a second enlarged cavity 18.