Abstract: Fluid flow control valve comprising a tubular body extending in a longitudinal direction with a fluid inlet and a fluid outlet situated respectively at the two longitudinal ends of the body, the valve comprising a nozzle and a piston connected to the body, the piston being housed in the body, the nozzle being made up of a part provided with a fluid passage having a calibrated dimension, the passage emerging at one end of the nozzle and forming a seat, said seat being situated against a terminal end of the piston forming a shutter preventing the flow of fluid in the closed position of the valve, the piston comprising a body defining a passage for the fluid in the body for the flow of the fluid between the inlet and the outlet, the body of the valve consisting of a material having a different expansion coefficient from the piston or the nozzle, the valve comprising a heating member which, depending on the heating power delivered, makes it possible to separate the end of the nozzle and the piston by differential

Abstract: A tube bundle for a steam condenser in which the projection on a plane perpendicular to the axis of the tubes of the envelope of the tube-containing zones of the bundle forms a trace of the type forming radiating spikes, wherein at least some of the spikes split at least once into branches, and wherein said spikes radiate from a tube-containing area that forms a substantially circular ring.