Abstract: An overheating and scaling control device for a fluid heating apparatus, such as a domestic water heater, removes the hot fluid in the heater when demand ceases. A piston (46) mobile within a case (28) separates the latter into two compartments (32, 36) respectively connected to the cold water supply pipe (16) and to the hot water discharge pipe (22). In operation, the pressure in pipe (16) is higher than the pressure in pipe (22) and piston (46) is moved to the left. On stopping, the pressures are equal in both pipes and spring (40) moves piston (46) to the right. Cold water is fed into the exchanger tube (20), so that the hot water contained in the latter is discharged into pipe (38) and compartment (36).

Abstract: An improvement to the plate-type heat exchangers/vaporators constituted in per se known manner by a stack of a plurality of rectangular plates each having four orifices in the vicinity of the apices of the rectangle and thus constituting juxtaposed parallelelpipedic racks, alternately traversed in countercurrent by the hot fluid and the cold fluid, said cold racks having at their apex located in the vicinity of the cold fluid intake a strip having flow holes defining a cold fluid supply chamber and an evaporation chamber where the cold fluid evaporates by flowing as thin trickles in contact with the hot wall, the four orifices of each plate serving respectively for the admission and discharge of the cold and hot fluids, wherein the cold fluid intake is provided with a fitting or lining of a thermally insulating material which serves to create, by reducing the intake diameter, a supplementary pressure drop for said cold fluid and brings about a greater thermal gradient between said cold fluid and the hot plate

Abstract: Distillation or concentration of a solution is carried out within a series of chambers C.sub.1, C.sub.2 . . . C.sub.n in which the pressures and the temperatures are of progressively decreasing value. Evaporation of the solution takes place within chamber C.sub.1 by indirect heat exchange with an auxiliary fluid. Evaporation of the solution takes place within each chamber C.sub.2 to C.sub.n by indirect heat exchange on the one hand with the vapor formed within the preceding chamber in order to condense the vapor and on the other hand with the auxiliary fluid which is continuously circulated from chamber C.sub.1 to chamber C.sub.n, the vapor formed within chamber C.sub.n being in turn condensed.

Abstract: The device for providing a leak-tight coupling between a flexible tube and a rigid coupling connector comprises two coaxial components adapted to fit one inside the other. One component is mounted within the flexible tube while the other component is fitted around the tube. Longitudinal ribs formed on one component are adapted to cooperate with longitudinal grooves in the other component at the time of interengagement of the two components. The end of the tube is thus clamped and securely held in position.

Abstract: A primary fluid is circulated within vertical flexible tubes enclosed within a fluid-tight shell and a secondary fluid flows over the external tube walls. A secondary fluid admission chamber is formed in the top portion of the shell by a horizontal tube plate traversed by primary fluid distribution means. The upper end of each tube is fixed on a unit of revolution having a passage for the primary fluid and constituted by a sliding ring and two components. The first component has a frusto-conical external surface which cooperates with the internal wall of the ring. The second component has a cylindrical external surface provided with grooves which define passages for the downflow of secondary fluid with the internal wall of a tube-plate hole.

Abstract: In evaporators for distillation or concentration of solutions, each tube nest consists of non-rigid plastic tubes through which vapor is circulated. Each tube is secured to the fixed structure of the evaporator at the vapor admission end of the tube by means of a standard fastening member and at the vapor discharge end by means of a sliding tubular expansion joint of small cross-sectional area compared with that of the tube.