Abstract: An apparatus (5) for controlling a water-pressurization system can be installed in a hydraulic circuit (1). The system includes an electric pump (2) connected to the hydraulic circuit (1) for pumping water therein, and an expansion vessel (3), provided with a valve (4) for controlling the pressure of the chamber containing air inside it, connected to the hydraulic circuit (1), designed to compensate for the variations of pressure to which the hydraulic circuit (1) is subjected in the steps of delivery of water.

Abstract: A water pressurization system is shown having a metal tank with a tank interior which is divided into first and second fluid chambers by a flexible membrane. One side of the tank interior is pressurized by compressed air. The membrane has a special coating applied thereto which decreases the natural permeability of the rubber material which is used to form the membrane. By decreasing the permeability of the membrane material, wear and tear on the membrane is decreased. The possibility of deloading the tank interior of pressurized gas due to the membrane permeability is also lessened.

Abstract: A membrane for autoclaves comprises a hollow elastomeric membrane body including a bottom portion mating with the bottom of the autoclave vessel, and a top portion including upwardly extending tubular lugs, the membrane body being made by any suitable injection molding method.