The invention relates to an ultrasonic tubular transducer to propagate acoustic waves in a fluid medium, and comprising:                an electromechanical conversion device with active elements associated with at least one metal tube transmitting the vibrations to the fluid medium,        a transmission system of the vibrations between the conversion device and the tube,        and a device for pre-stressing the active elements of said conversion device.        
Tubular ultrasonic transducers enable radial vibrations to be created and waves able to cause cavitation to be propagated in media, in particular fluid media, and find their applications in precision cleaning or sonochemistry, such as extraction of substances or of particle deposition. Their purpose is in particular to generate ultrasounds:                within the fluid and in proximity to the surface to be treated to maximize the efficiency of the installation,        over the whole of the surface to be treated, which may have a length of up to several metres,        with an amplitude that is as uniform as possible for the surface treatment to be homogeneous,        in a direction perpendicular to the surface to be treated to limit losses and to maximize the efficiency.        