An expansion tank includes a tank body mounted inside a housing forming a sump, where the tank body defines an internal expansion volume. A fluid inlet tube on the tank body has an upper end open to the sump and a lower end open to the internal expansion volume. A single 2-way check valve is located at the lower end of the tube, and fluid enters the expansion volume when the pressure in the sump exceeds the pressure in the expansion volume by a first predetermined amount, and fluid exits the expansion volume to the sump when the pressure in the expansion volume exceeds the pressure in the sump by a second predetermined amount. The check valve may be a combination duckbill valve and umbrella valve. The tank body may include a cover on which the inlet tube is formed.

A vent for selectively sealing an opening of an enclosed chamber includes a body, a first poppet, a second poppet, and a face seal. The body is configured to be coupled to the enclosed chamber. The first poppet is disposed within the body and is biased by a first biasing member. The first poppet includes a first surface. The second poppet is disposed within the body and includes a second surface. The second poppet is biased toward the first poppet such that the second surface is biased toward engaging the first surface. The face seal is positioned between the first surface and the second surface.

A valve for removing gases during the startup of liquid handling facilities and/or the filling of liquid storage facilities includes a housing and internal parts which include a highly buoyant float, a pivotal linkage member, a valve guiding member, and a poppet valve. The poppet valve includes a passage there through that allows for degassing of the liquid handling facility or liquid storage facility. The valve also provides for degassing of such facilities when gases build up therein, and provides for vacuum relief when an internal vacuum is produced in such facilities due to removal of liquid.

A valve for removing gases during the startup of liquid handling facilities and/or the filling of liquid storage facilities includes a housing and internal parts which include a highly buoyant float, a pivotal linkage member, a valve guiding member, and a poppet valve. The poppet valve includes a passage there through that allows for degassing of the liquid handling facility or liquid storage facility. The valve also provides for degassing of such facilities when gases build up therein, and provides for vacuum relief when an internal vacuum is produced in such facilities due to removal of liquid.

A liquid storage tank has a breathing valve that vents the tank's headspace at a high-pressure value and admits an ambient gas at a low-pressure value. A controller generates a first control signal when the percentage of the catalyst gas is less than a catalyst threshold, a second control signal when the percentage of the catalyst gas exceeds the catalyst threshold, and a third control signal when the pressure in the headspace is equal to a low-pressure threshold between the breathing valve's low-pressure value and high-pressure value. The first valve is only opened to output inert gas at a discharge pressure greater than the breathing valve's high-pressure value in response to the second control signal. The second valve is only opened to output inert gas at a discharge pressure that is between the breathing valve's low-pressure value and high-pressure value in response to the third control signal.

A P/V valve that can be positioned at a working height above grade (i.e., a height reachable by a service technician positioned at grade) while still providing appropriate resistance to fire and explosion by venting to atmosphere at an appropriate height above grade (e.g., 12 feet) is disclosed. In certain exemplifications of the present disclosure, the P/V valve features a diaphragm actuated two-way poppet valve actuatable by a valve piston. In alternative exemplifications of the present disclosure, the P/V valve is positioned intermediate grade and the distal end of a P/V valve riser pipe and is contained in a vault fluidly connected to the P/V valve riser pipe, the P/V valve locally venting in the vault, which is hermetically sealed to the P/V valve riser pipe.

A P/V valve that can be positioned at a working height above grade (i.e., a height reachable by a service technician positioned at grade) while still providing appropriate resistance to fire and explosion by venting to atmosphere at an appropriate height above grade (e.g., 12 feet) is disclosed. In certain exemplifications of the present disclosure, the P/V valve features a diaphragm actuated two-way poppet valve actuatable by a valve piston. In alternative exemplifications of the present disclosure, the P/V valve is positioned intermediate grade and the distal end of a P/V valve riser pipe and is contained in a vault fluidly connected to the P/V valve riser pipe, the P/V valve locally venting in the vault, which is hermetically sealed to the P/V valve riser pipe.

A hydraulic system comprises a valve distributor comprising one or more sections connectable to respective uses, a supply apparatus comprising a pump and a supply channel, a discharge channel connected to a low-pressure tank, a use signal channel coming from the section of the valve distributor and further comprises a hydraulic regulating device connected via said channels which includes a 2-position 3-way proportional valve configured so as to provide operative fluid at a conditioned pressure, different with respect to the pressure that is characteristic of the operative condition of use, to the supply apparatus and at least one proportional pressure reducing valve.

A hydraulic system comprises a valve distributor comprising one or more sections connectable to respective uses, a supply apparatus comprising a pump and a supply channel, a discharge channel connected to a low-pressure tank, a use signal channel coming from the section of the valve distributor and further comprises a hydraulic regulating device connected via said channels which includes a 2-position 3-way proportional valve configured so as to provide operative fluid at a conditioned pressure, different with respect to the pressure that is characteristic of the operative condition of use, to the supply apparatus and at least one proportional pressure reducing valve.

A wind turbine having a nacelle, with at least one liquid circuit with a coolant, a cooling section for cooling a component of the wind turbine using the coolant, a cooler for cooling the coolant, a piping system for conveying the coolant and an expansion tank for obtaining an operating pressure of the liquid circuit, wherein the expansion tank establishes a pressure in the liquid circuit using static pressure of a liquid column.