Large demension bellow is a component part of launch vehicle fuel system. Its desing perceives the loading of hydraulic hammer at the moment of propulsion system initiation. This work concerns the improvement of technology providing increasing of performance characteristics and constructional reliability. Using in product desing jointless bellow realized by hydraulic forming from weldless round billet instead of bellow realized by welding from separate stamped terms (stocks), allows greatly increase its reliability at the expense of runs reduction, such as: welding of separate stocks, fettling and weld seams X-raying. The purpose of work is a method of receiption of large demension bellow by hydraulic forming from weldless round billet.