Patent ID: 6668867
Filing Date: 2003-12-30
Classification: F16L

Abstract:
A flexible metal tube having a longitudinal axis, the tube comprising at least one strip of approximately constant thickness wound helically in turns about the axis, the strip having opposite first and second edges,the strip having at least one closed box element extending along the length of the strip and along the first edge, the box element having walls formed by portions of the same turn of the strip, the walls including an upper wall and a lower wall, the other second edge of the strip terminating in a free edge, the box element having a trapezoidal cross-section; a radial bulge directed radially towards the upper wall of the box element and located between the box element and the second free edge of the strip; and the turns of the strip are wound so that the free second edge of the strip in each turn is curved and is housed in the radial bulge of the adjacent turn of the strip.