Abstract: A vent system for a fuel storage tank and a pressure vacuum valve (PVV) module for use with such a vent system are disclosed. The vent system defines a vent path from the fuel storage tank to atmosphere. An elongate vent pipe extends vertically to a rain cap located at the upper end of the vent pipe. A pressure vacuum valve (PVV) is located in the vent path between the lower end of the vent pipe and the tank. The pressure vacuum valve maintains the vent path in a closed condition unless the pressure in the tank is above or below a predetermined pressure. By separating the PVV from the rain cap and placing it between the lower end of the vent pipe and the tank, it is possible to site the PVV at an accessible level for maintenance.

Abstract: A vent system for a fuel storage tank and a pressure vacuum valve (PVV) module for use with such a vent system are disclosed. The vent system defines a vent path from the fuel storage tank to atmosphere. An elongate vent pipe extends vertically to a rain cap located at the upper end of the vent pipe. A pressure vacuum valve (PVV) is located in the vent path between the lower end of the vent pipe and the tank. The pressure vacuum valve maintains the vent path in a closed condition unless the pressure in the tank is above or below a predetermined pressure. By separating the PVV from the rain cap and placing it between the lower end of the vent pipe and the tank, it is possible to site the PVV at an accessible level for maintenance.

Abstract: A float valve is mounted within the ullage of a liquid storage tank and is fitted to a lower end of a vapour vent line. The float valve includes a generally tubular vent body having an opening arrangement which allows vapour to escape from the tank into the vent line, and a float assembly which undergoes damped upward movement in response to the liquid level within the tank exceeding a threshold level. The float assembly comprises a sleeve and a float arrangement separated from each other by an adjustable distance. In this way, the volume of liquid required in the tank to make the float assembly move upward can be changed. The float valve may include a relief valve or a plug with a bleed orifice to permit vapour flow from the tank to the vapour vent line in the event that the pressure within the tank exceeds a predetermined value.

Abstract: A flow diffuser adapted to be fitted to the exit end of the fill tube of a fuel tank having slot like apertures which are arranged to extend substantially at right angles to the axis of the fill. A deflector is fitted into the base of the diffuser and is formed with an opening to allow the passage of a dipstick.

Abstract: A fuel storage tank includes an overfill protection device for shutting off the flow of fuel into the tank via a fuel fill tube when the contents of the tank reach an intended maximum fill level. The overfill protection device includes a butterfly valve located within the fuel fill tube and a float, slidably mounted outside the fuel fill tube and operatively linked to the butterfly valve. The float rotates the butterfly valve towards the closed position in response to an increasing fuel level in the tank.

Abstract: A flow diffuser adapted to be fitted to the exit end of the fill tube of a fuel tank having slot like apertures which are arranged to extend substantially at right angles to the axis of the fill. A deflector is filled into the base of the diffuser and is formed with an opening to allow the passage of a dipstick.