A fluid flow control device can include an inlet port and an outlet port. The fluid flow control device can also include a rotatable component for rotating about an axis in response to fluid flow from the inlet port. A float component positioned within the rotatable component can move between (i) an open position that enables fluid flow from the inlet port to the outlet port, and (ii) a closed position that restricts fluid flow from the inlet port to the outlet port. The float component can move from the open position to the closed position in response to a fluid from the inlet port having one density. The float component can move from the closed position to the open position in response to the fluid from the inlet port having another density.

A fluid flow control device includes a rotatable component for rotating about an axis in response to fluid flow from an inlet port of the fluid flow control device. A float component is positioned within the rotatable component and connected to the rotatable component by a hinge. The hinge provides for movement of the float component relative to the rotatable component between (i) an open position that enables fluid flow from the inlet port to an outlet port of the rotatable component, and (ii) a closed position that restricts fluid flow through a flow passage from the inlet port to the outlet port.

A fluid flow control device includes a rotatable component for rotating about an axis in response to fluid flow from an inlet port of the fluid flow control device. A float component is positioned within the rotatable component and connected to the rotatable component by a hinge. The hinge provides for movement of the float component relative to the rotatable component between (i) an open position that enables fluid flow from the inlet port to an outlet port of the rotatable component, and (ii) a closed position that restricts fluid flow through a flow passage from the inlet port to the outlet port.

Some embodiments include a fluid valve assembly with an outlet base dimensioned to be positioned through a drain in a fluid tank, and a float assembly including a moveable float. The moveable float can form a fluid-tight seal at a first end when the moveable float is coupled to the outlet base, and a flow opening when the moveable float is at least partially decoupled from the outlet base. Some embodiments include a housing positioned with the moveable float, where the housing encloses a suction device coupled to a moveable piston. Some embodiments include an actuable diaphragm positioned in the outlet base, and a compressed air tube or passageway coupled to one side the actuable diaphragm. In some embodiments, the actuable diaphragm is configured and arranged to be actuated by compressed air to move the moveable piston.

Some embodiments include a fluid valve assembly with an outlet base dimensioned to be positioned through a drain in a fluid tank, and a float assembly including a moveable float. The moveable float can form a fluid-tight seal at a first end when the moveable float is coupled to the outlet base, and a flow opening when the moveable float is at least partially decoupled from the outlet base. Some embodiments include a housing positioned with the moveable float, where the housing encloses a suction device coupled to a moveable piston. Some embodiments include an actuable diaphragm positioned in the outlet base, and a compressed air tube or passageway coupled to one side the actuable diaphragm. In some embodiments, the actuable diaphragm is configured and arranged to be actuated by compressed air to move the moveable piston.

A thermal battery including a storage vessel as well as an inlet pipe and an outlet pipe for a fluid that are connected to a circulation circuit is disclosed. The thermal battery also has at least two shut-off valves placed on the inlet pipe and the fluid outlet pipe, respectively, to isolate the fluid contained in the storage vessel when the circulation circuit of the fluid is shut off. The shut-off valves are automatic and include an enclosure containing the fluid and including an inlet and an outlet for the fluid, and a float that is moveable between: an upper position in which the float floats and obstructs at least the outlet when the circulation circuit is shut off, and a lower position in which the float is submerged and allows the fluid to flow between the inlet and the outlet when the circulation circuit is operational.

A thermal battery including a storage vessel as well as an inlet pipe and an outlet pipe for a fluid that are connected to a circulation circuit is disclosed. The thermal battery also has at least two shut-off valves placed on the inlet pipe and the fluid outlet pipe, respectively, to isolate the fluid contained in the storage vessel when the circulation circuit of the fluid is shut off. The shut-off valves are automatic and include an enclosure containing the fluid and including an inlet and an outlet for the fluid, and a float that is moveable between: an upper position in which the float floats and obstructs at least the outlet when the circulation circuit is shut off, and a lower position in which the float is submerged and allows the fluid to flow between the inlet and the outlet when the circulation circuit is operational.

A float valve assembly includes a cylindrical housing defining an inner flow path and a check valve is positioned within the housing and movable between an open position, where uphole and downhole fluid flow through the inner flow path is allowed, and a closed position, where uphole fluid flow is prevented while downhole fluid flow is allowed. An activation member is movably positioned within the housing between a first position, where the activation member holds the check valve in the open position, and a second position, where the activation member moves axially and out of engagement with the check valve. A drag body is coupled to the activation member and fluid flow in the downhole direction generates a drag force on the drag body that places an axial force on the activation member to move the activation member to the second position.

A float valve assembly includes a cylindrical housing defining an inner flow path and a check valve is positioned within the housing and movable between an open position, where uphole and downhole fluid flow through the inner flow path is allowed, and a closed position, where uphole fluid flow is prevented while downhole fluid flow is allowed. An activation member is movably positioned within the housing between a first position, where the activation member holds the check valve in the open position, and a second position, where the activation member moves axially and out of engagement with the check valve. A drag body is coupled to the activation member and fluid flow in the downhole direction generates a drag force on the drag body that places an axial force on the activation member to move the activation member to the second position.

A water hammer-proof air valve that has a valve body and a bonnet, that are fixedly connected, a valve opening is provided on the valve body, and a high-speed intake and exhaust device is provided in an inner cavity of the valve body. A bonnet opening is provided on the bonnet, an output end of the high-speed intake and exhaust device penetrates the bonnet opening and is communicated with a high-speed exhaust throttling device for limiting an exhaust amount of gas of the high-speed intake and exhaust device, an output end of the high-speed exhaust throttling device is communicated with an outside air, and a trace exhaust device for discharging the gas separated out from the pipeline to the outside through the high-speed exhaust throttling device after the high-speed intake and exhaust device closes the valve is further provided in the high-speed intake and exhaust device.