Abstract: A flexible metal tube with closed section and a flexible pipe comprising such a metal tube, comprising a strip with substantially constant thickness and wound helically around an axis, the strip includes at least a closed section having walls formed by portions of a common turn of the strip, the closed section includes an upper wall and a lower wall and the section is arranged at one end of said strip while the other end terminates in a free edge. The closed section is trapezoidal in cross-section. A bulge radially oriented towards the upper wall of the closed section is provided between the closed section and the free edge of the stirrup. The invention is in particular applicable to flexible tubular pipes.