Abstract: Seal comprising annular baseplate 5, carried on the surface of shaft 7, and main annular body 2, with annular metal reinforcement 3, comprising a continuous spring cast into the body, said annular body 2 being connected to baseplate 5 via flexible neck 4, and extended by lip 1, the exterior annular surface of which bears on the bore sidewall of tube 6, so that when an axial thrust, exerted by mobile actuator part 9, is applied to said annular body 2, the body is straightened, pivoting with respect to baseplate 5, and lip 1 bears on the sidewall of tube 6.Applications in the petroleum industry, in particular for the repair of pipes, and testing tubes at high pressures.