Systems, methods, and devices for relieving overpressure associated with thermal expansion of fluid within a closed cavity of a subsea manifold assembly. The subsea manifold assembly may comprise a header bore fluidly connected to one or more branch connections. A unidirectional valve is included at the branch connections to allow fluid leakage from the closed cavity into a header bore of the subsea manifold assembly to thereby reduce a pressure within the cavity while in the closed position.

A valve arrangement for a fluid control system has a housing, comprising a fluid inlet, a fluid outlet, and extending along a central axis. The valve arrangement has a valve component, movable along the central axis between a first position, closing the fluid inlet, and a second position, a maximum valve lift defined therebetween. The valve arrangement has a biasing member, biasing the valve component towards the first position, and an intermediate component movable along the central axis, and relative to the valve component. The valve arrangement has a first stop and a second stop, the intermediate component axially movable therebetween, a range of the relative axial movement being less than the maximum valve lift. During an initial axial movement of the valve component from the first position, the intermediate component moves relative to the first stop and the second stop, and upon the intermediate component reaching the limit of the range of relative axial movement a subsequent movement of the valve component is opposed by an intermediate frictional force generated by the intermediate component.

A valve assembly includes a housing having an interior wall defining a chamber having a longitudinal axis. A piston is disposed in the chamber and is movable between first and second positions along the longitudinal axis, wherein the piston includes a piston head. The piston head has opposite first and second sides, longitudinally spaced first and second peripheral grooves disposed between the first and second sides, wherein the first and second grooves define a space therebetween, and a relief passage extending radially inwardly from the first groove and communicating between the space and the first side of the piston. Longitudinally spaced first and second O-rings are disposed in the first and second grooves and engage the interior wall.

A variable flow check valve device includes an inlet connected with a first pressure fluid reservoir, an outlet connected with a second pressure fluid reservoir, which is separate and/or separable from the first pressure fluid reservoir, a check valve closing member that opens and closes the outlet in response to a pressure difference of the pressure fluid on opposite sides of the check valve closing member, and a spool valve with a movable spool in a flow path of the pressure fluid extending from the inlet to the outlet. The spool valve forms a variable orifice within the flow path of the pressure fluid. The variable flow check valve device includes a force balancing unit in the flow path which creates a balancing force to at least partially counteract a force acting on the spool when the pressure fluid passes the spool valve.

Embodiments of the presently disclosed subject matter relate to systems and methods for a pool pump. The pool pump may comprise an impeller, an inlet for receiving a liquid, an outlet for supplying the liquid, a chamber above the impeller configured to receive air from the liquid. The pool pump may further comprise a buoy or an exhaust plug configured to release exhaust gas from within the pool pump. A seal configured to seal against a sealing surface of a top cover to seal the chamber.

Embodiments of the presently disclosed subject matter relate to systems and methods for a pool pump. The pool pump may comprise an impeller, an inlet for receiving a liquid, an outlet for supplying the liquid, a chamber above the impeller configured to receive air from the liquid. The pool pump may further comprise a buoy or an exhaust plug configured to release exhaust gas from within the pool pump. A seal configured to seal against a sealing surface of a top cover to seal the chamber.

Embodiments of the presently disclosed subject matter relate to systems and methods for a pool pump. The pool pump may comprise an impeller, an inlet for receiving a liquid, an outlet for supplying the liquid, a chamber above the impeller configured to receive air from the liquid. The pool pump may further comprise a buoy or an exhaust plug configured to release exhaust gas from within the pool pump. A seal configured to seal against a sealing surface of a top cover to seal the chamber.

An example refrigerant control valve includes: a modulating plug that is linearly movable to control refrigerant flow rate from a first port to a second port; a first chamber formed at a first side of the modulating plug and fluidly coupled to the first port; a second chamber formed at a second side of the modulating plug, opposite the first side; a first flow restriction that fluidly couples the first chamber to the second chamber, and a second flow restriction that fluidly couples the second chamber to the second port.

Embodiments of the presently disclosed subject matter relate to systems and methods for a pool pump. The pool pump may comprise an impeller, an inlet for receiving a liquid, an outlet for supplying the liquid, a chamber above the impeller configured to receive air from the liquid. The pool pump may further comprise a buoy or an exhaust plug configured to release exhaust gas from within the pool pump. A seal configured to seal against a sealing surface of a top cover to seal the chamber.