A flush valve apparatus comprising a main body, an outer cover, an inner cover, a valve assembly, and a back-pressure chamber, wherein the outer cover is coupled to an upper end of the main body, the inner cover is positioned over the valve assembly and under the outer cover, the valve assembly comprises a valve body and is positioned at an interior of the main body, the back-pressure chamber is defined by a lower surface of the inner cover and an upper surface of the valve assembly, and wherein one or more springs are positioned substantially vertically in the back-pressure chamber. The one or more springs are effective towards minimizing flush water variation between flush cycles and towards attenuation flush valve erratic behavior.

A flush valve apparatus comprising a main body, an outer cover, an inner cover, a valve assembly, and a back-pressure chamber, wherein the outer cover is coupled to an upper end of the main body, the inner cover is positioned over the valve assembly and under the outer cover, the valve assembly comprises a valve body and is positioned at an interior of the main body, the back-pressure chamber is defined by a lower surface of the inner cover and an upper surface of the valve assembly, and wherein one or more springs are positioned substantially vertically in the back-pressure chamber. The one or more springs are effective towards minimizing flush water variation between flush cycles and towards attenuation flush valve erratic behavior.

It is described a subsea electric actuator (100) operating a linear valve (200), the actuator (100) comprising a roller-screw (2) for translating a rotational movement of a motor (3) to a linear movement of a gate rod (4) operating the valve (200), the actuator (100) comprising: —an actuator housing (101); —an outer roller screw part (2′) rotationally connected to the motor (3) and comprising internal threads forming a first part of a first connection (10), —an inner roller screw part (2″) comprising external threads forming a second part of the first connection (10) and being arranged inside the outer roller screw part (2′), a surface of the inner roller screw part (2″) having a first interface forming a first part of a second connection (20′; 20″) connecting the inner roller screw part (2″) to a non-rotational part of the actuator (100), the second connection (20′, 20″) is configured to rotationally lock the inner roller screw part (2′) giving linear movement of the inner roller screw part (2″) when the outer roller screw (2′) is rotated, —a gate rod (4) arranged axially movable inside the inner roller screw part (2″), the external surface of the gate rod (4) comprising an interface forming a first part of a third connection (30′; 30″), —an override housing (6) arranged outside the gate rod (4) and adjacent the inner roller screw part (2″) forming an axial stop for the inner roller screw part (2″), the override housing (6) comprising an interface forming a second part of the third connection (30′; 30″), and wherein, when the third connection (30′; 30″) is connected, the inner roller screw part (2″) is locked to the gate rod (4) such that the gate rod (4) follows any axial movement of the inner roller screw part (2″), and when the third connection (30′; 30″) is disconnected, the gate rod (4) is allowed to move in the axial direction relative the inner roller screw part (2″) such that the linear valve (200) can be operated independently of the motor (3), outer roller screw part (2′) and inner roller screw part (2″). It is further described a method of performing override of a subsea electric actuator (100).

It is described a subsea electric actuator (100) operating a linear valve (200), the actuator (100) comprising a roller-screw (2) for translating a rotational movement of a motor (3) to a linear movement of a gate rod (4) operating the valve (200), the actuator (100) comprising: —an actuator housing (101); —an outer roller screw part (2′) rotationally connected to the motor (3) and comprising internal threads forming a first part of a first connection (10), —an inner roller screw part (2″) comprising external threads forming a second part of the first connection (10) and being arranged inside the outer roller screw part (2′), a surface of the inner roller screw part (2″) having a first interface forming a first part of a second connection (20′; 20″) connecting the inner roller screw part (2″) to a non-rotational part of the actuator (100), the second connection (20′, 20″) is configured to rotationally lock the inner roller screw part (2′) giving linear movement of the inner roller screw part (2″) when the outer roller screw (2′) is rotated, —a gate rod (4) arranged axially movable inside the inner roller screw part (2″), the external surface of the gate rod (4) comprising an interface forming a first part of a third connection (30′; 30″), —an override housing (6) arranged outside the gate rod (4) and adjacent the inner roller screw part (2″) forming an axial stop for the inner roller screw part (2″), the override housing (6) comprising an interface forming a second part of the third connection (30′; 30″), and wherein, when the third connection (30′; 30″) is connected, the inner roller screw part (2″) is locked to the gate rod (4) such that the gate rod (4) follows any axial movement of the inner roller screw part (2″), and when the third connection (30′; 30″) is disconnected, the gate rod (4) is allowed to move in the axial direction relative the inner roller screw part (2″) such that the linear valve (200) can be operated independently of the motor (3), outer roller screw part (2′) and inner roller screw part (2″). It is further described a method of performing override of a subsea electric actuator (100).

A valve override assembly, comprising: a housing comprising a first portion including a cavity and a second portion. The first portion and the second portion arranged along an axial direction. A core arranged at least partially within the cavity of the first portion of the housing, wherein the core is movable with respect to the housing along the axial direction and comprises a first engagement portion. An override member arranged at least partially within the second portion of the housing such that the override member is movable with respect to the housing along the axial direction.

The present invention discloses an executive system for driving a valve to open and close, comprising a first housing, a linkage block, a first drive rod and a drive mechanism. Wherein, the first housing has a first inner cavity; a medium channel is provided in a side wall of the first housing; an outer peripheral wall of the linkage block is arranged on a wall of the first inner cavity in a slidable and sealed manner, and the linkage block partitions the first inner cavity into an upper cavity and a lower cavity; the medium channel is communicated with the upper cavity; a bottom part of the first drive rod sequentially passes through a top part of the first housing and the linkage block and extends into the lower cavity; a position-limiting part on the bottom part of the first drive rod blocks the linkage block within a region between the position-limiting part and the top part of the first housing; the drive mechanism is provided on top of the first drive rod. The degree of friction between an outer peripheral wall of the linkage block and an inner surface of the first housing is reduced, and the probability of a gap being produced between the peripheral wall of the linkage block and the inner wall of the first housing is reduced, so that the first drive rod can drive the valve stem to move into position, thereby increasing the reliability of the executive system controlling the valve to open and close.

The present invention discloses an executive system for driving a valve to open and close, comprising a first housing, a linkage block, a first drive rod and a drive mechanism. Wherein, the first housing has a first inner cavity; a medium channel is provided in a side wall of the first housing; an outer peripheral wall of the linkage block is arranged on a wall of the first inner cavity in a slidable and sealed manner, and the linkage block partitions the first inner cavity into an upper cavity and a lower cavity; the medium channel is communicated with the upper cavity; a bottom part of the first drive rod sequentially passes through a top part of the first housing and the linkage block and extends into the lower cavity; a position-limiting part on the bottom part of the first drive rod blocks the linkage block within a region between the position-limiting part and the top part of the first housing; the drive mechanism is provided on top of the first drive rod. The degree of friction between an outer peripheral wall of the linkage block and an inner surface of the first housing is reduced, and the probability of a gap being produced between the peripheral wall of the linkage block and the inner wall of the first housing is reduced, so that the first drive rod can drive the valve stem to move into position, thereby increasing the reliability of the executive system controlling the valve to open and close.

It is described a subsea electric actuator (100) operating a linear valve (200), the actuator (100) comprising a roller-screw (2) for translating a rotational movement of a motor (3) to a linear movement of a gate rod (4) operating the valve (200), the actuator (100) comprising: —an actuator housing (101); —an outer roller screw part (2′) rotationally connected to the motor (3) and comprising internal threads forming a first part of a first connection (10), —an inner roller screw part (2″) comprising external threads forming a second part of the first connection (10) and being arranged inside the outer roller screw part (2′), a surface of the inner roller screw part (2″) having a first interface forming a first part of a second connection (20′; 20″) connecting the inner roller screw part (2″) to a non-rotational part of the actuator (100), the second connection (20′, 20″) is configured to rotationally lock the inner roller screw part (2′) giving linear movement of the inner roller screw part (2″) when the outer roller screw (2′) is rotated, —a gate rod (4) arranged axially movable inside the inner roller screw part (2″), the external surface of the gate rod (4) comprising an interface forming a first part of a third connection (30′; 30″), —an override housing (6) arranged outside the gate rod (4) and adjacent the inner roller screw part (2″) forming an axial stop for the inner roller screw part (2″), the override housing (6) comprising an interface forming a second part of the third connection (30′; 30″), and wherein, when the third connection (30′; 30″) is connected, the inner roller screw part (2″) is locked to the gate rod (4) such that the gate rod (4) follows any axial movement of the inner roller screw part (2″), and when the third connection (30′; 30″) is disconnected, the gate rod (4) is allowed to move in the axial direction relative the inner roller screw part (2″) such that the linear valve (200) can be operated independently of the motor (3), outer roller screw part (2′) and inner roller screw part (2″). It is further described a method of performing override of a subsea electric actuator (100).

It is described a subsea electric actuator (100) operating a linear valve (200), the actuator (100) comprising a roller-screw (2) for translating a rotational movement of a motor (3) to a linear movement of a gate rod (4) operating the valve (200), the actuator (100) comprising: —an actuator housing (101); —an outer roller screw part (2′) rotationally connected to the motor (3) and comprising internal threads forming a first part of a first connection (10), —an inner roller screw part (2″) comprising external threads forming a second part of the first connection (10) and being arranged inside the outer roller screw part (2′), a surface of the inner roller screw part (2″) having a first interface forming a first part of a second connection (20′; 20″) connecting the inner roller screw part (2″) to a non-rotational part of the actuator (100), the second connection (20′, 20″) is configured to rotationally lock the inner roller screw part (2′) giving linear movement of the inner roller screw part (2″) when the outer roller screw (2′) is rotated, —a gate rod (4) arranged axially movable inside the inner roller screw part (2″), the external surface of the gate rod (4) comprising an interface forming a first part of a third connection (30′; 30″), —an override housing (6) arranged outside the gate rod (4) and adjacent the inner roller screw part (2″) forming an axial stop for the inner roller screw part (2″), the override housing (6) comprising an interface forming a second part of the third connection (30′; 30″), and wherein, when the third connection (30′; 30″) is connected, the inner roller screw part (2″) is locked to the gate rod (4) such that the gate rod (4) follows any axial movement of the inner roller screw part (2″), and when the third connection (30′; 30″) is disconnected, the gate rod (4) is allowed to move in the axial direction relative the inner roller screw part (2″) such that the linear valve (200) can be operated independently of the motor (3), outer roller screw part (2′) and inner roller screw part (2″). It is further described a method of performing override of a subsea electric actuator (100).

A pneumatic trip valve that may include a valve structure, a switch plate air path and an internal check valve. In various aspects, the pneumatic trip valve may be connected to a valve positioner, an actuator, or a combination thereof to control the operation of a fluid process control valve. In operation, the Pneumatic trip valve acts to put the actuator in a preset fail-safe position when the actuator loses sufficient pressure or communication from a main air supply, stored pressurized air from an actuator air reservoir, and/or an external air reservoir.