A system for preventing over pressure in a flexible tank when connected to a water grid that includes the flexible tank and a control unit. An inlet of the tank is connected to the water grid through the control unit. The control unit includes a closed box, an inlet that is connected to the water grid, an outlet that is connected to the inlet of the tank, and a float valve. The user place the flexible tank and set the float so that it will be opened or closed in a certain height of activating water level in the control unit and to place the control unit in a way that the activating water level is at the same level of a desired water level of the flexible tank.

A system for preventing over pressure in a flexible tank when connected to a water grid that includes the flexible tank and a control unit. An inlet of the tank is connected to the water grid through the control unit. The control unit includes a closed box, an inlet that is connected to the water grid, an outlet that is connected to the inlet of the tank, and a float valve. The user place the flexible tank and set the float so that it will be opened or closed in a certain height of activating water level in the control unit and to place the control unit in a way that the activating water level is at the same level of a desired water level of the flexible tank.

A pressure measuring system is provided in which a closing element supported in the pressure fitting channel is activated or displaced by a pressure surge or a pressure wave and thereby seals the channel to the measuring element and thus prevents an outflow of the fluid.

A pressure measuring system is provided in which a closing element supported in the pressure fitting channel is activated or displaced by a pressure surge or a pressure wave and thereby seals the channel to the measuring element and thus prevents an outflow of the fluid.

A cam assembly for use in a slam-shut safety valve includes a cam having an elongated first cam arm, and the cam is pivotable about a rotational axis. The cam assembly also includes a torsional spring having a pair of stationary outer arms and a pair of pivotable inner arms, wherein the pair of stationary inner arms is coupled to a portion of the first cam arm. The pair of inner arms is adapted to act on the first cam arm to bias the cam into a position that allows the cam to be relatched in a valve rearming process. The pair of inner arms is symmetrically disposed about the first cam arm to prevent lateral displacement of the cam.