A bonnet seal assembly for a gate valve includes a generally cylindrical packing nut positioned in the stem bore around the valve stem. The packing nut includes first and second spaced-apart annular sealing surfaces, and the bonnet seal assembly includes a third annular sealing surface connected to or formed integrally with the valve stem and a fourth annular sealing surface formed concentrically in the stem bore. In a first position of the valve stem, the first annular sealing surface sealingly engages the third annular sealing surface to thereby form a first seal between the valve stem and the packing nut, and the second annular sealing surface sealing engages the fourth annular sealing surface to thereby form a second seal between the packing nut and the stem bore. In this manner, the first and second seals together operate to seal the stem bore from fluid pressure in the gate cavity.

A bonnet seal assembly for a gate valve includes a generally cylindrical packing nut positioned in the stem bore around the valve stem. The packing nut includes first and second spaced-apart annular sealing surfaces, and the bonnet seal assembly includes a third annular sealing surface connected to or formed integrally with the valve stem and a fourth annular sealing surface formed concentrically in the stem bore. In a first position of the valve stem, the first annular sealing surface sealingly engages the third annular sealing surface to thereby form a first seal between the valve stem and the packing nut, and the second annular sealing surface sealing engages the fourth annular sealing surface to thereby form a second seal between the packing nut and the stem bore. In this manner, the first and second seals together operate to seal the stem bore from fluid pressure in the gate cavity.

An expansion tank includes a tank body mounted inside a housing forming a sump, and defining an internal expansion volume. A fluid inlet opening in the tank body is in communication with the sump and the expansion volume. A combination valve may be disposed on a lower end of the tank to control fluid flow between the sump and the expansion volume. The valve may be a combination duckbill valve and umbrella valve. Fluid enters the expansion volume through the umbrella valve when sump pressure exceeds expansion volume pressure by a first predetermined amount, and fluid exits the expansion volume through the duckbill valve to the sump when expansion volume pressure exceeds sump pressure by a second predetermined amount. The tank body may include a cover on which an inlet tube is formed.

An expansion tank includes a tank body mounted inside a housing forming a sump, and defining an internal expansion volume. A fluid inlet opening in the tank body is in communication with the sump and the expansion volume. A combination valve may be disposed on a lower end of the tank to control fluid flow between the sump and the expansion volume. The valve may be a combination duckbill valve and umbrella valve. Fluid enters the expansion volume through the umbrella valve when sump pressure exceeds expansion volume pressure by a first predetermined amount, and fluid exits the expansion volume through the duckbill valve to the sump when expansion volume pressure exceeds sump pressure by a second predetermined amount. The tank body may include a cover on which an inlet tube is formed.

A buffer valve is installed on a pneumatic diaphragm valve. An inner flow channel of the buffer valve includes an inner micro gas hole, an inner chamber, an outer gas hole, and a floating ball. The buffer valve has functions with a high-filling action, a shielding action, a releasing action, a shielding time Δt, and an adjusting mechanism. When inflatable, the floating ball will not block the inner micro hole to be quickly filled with high-pressure gas. when gas discharge, the floating ball will move to the outer gas hole with the gas flow and produce the shielding action to reduce the discharge rate to reduce the vibration and slow down the approach speed of the diaphragm to reduce the impact against the valve seat. When the pressure of the gas decreases, the floating ball is separated from the outer gas hole by the releasing action to accelerate the discharge.

A buffer valve is installed on a pneumatic diaphragm valve. An inner flow channel of the buffer valve includes an inner micro gas hole, an inner chamber, an outer gas hole, and a floating ball. The buffer valve has functions with a high-filling action, a shielding action, a releasing action, a shielding time Δt, and an adjusting mechanism. When inflatable, the floating ball will not block the inner micro hole to be quickly filled with high-pressure gas. when gas discharge, the floating ball will move to the outer gas hole with the gas flow and produce the shielding action to reduce the discharge rate to reduce the vibration and slow down the approach speed of the diaphragm to reduce the impact against the valve seat. When the pressure of the gas decreases, the floating ball is separated from the outer gas hole by the releasing action to accelerate the discharge.

A one-way valve to control the release of pressurized gas from within a sealed container through a venting aperture. The valve comprises a layer of flexible material having an upper and a lower surface with a portion of the upper surface adhered to a surface of the container and overlaying the venting aperture. A channel is defined by a portion of the container and an adjacent portion of the flexible material which has not been adhered to the container. The channel is in communication with the venting aperture and an exhaust gas aperture in the layer of flexible material. The channel is operable between a closed and an open configuration upon gas pressure within the container exceeding a predetermined limit. When open the channel permits gas to flow from said container into the exterior atmosphere. When closed the channel restricts the flow of gas between the venting aperture and exhaust gas aperture.

A one-way valve to control the release of pressurized gas from within a sealed container through a venting aperture. The valve comprises a layer of flexible material having an upper and a lower surface with a portion of the upper surface adhered to a surface of the container and overlaying the venting aperture. A channel is defined by a portion of the container and an adjacent portion of the flexible material which has not been adhered to the container. The channel is in communication with the venting aperture and an exhaust gas aperture in the layer of flexible material. The channel is operable between a closed and an open configuration upon gas pressure within the container exceeding a predetermined limit. When open the channel permits gas to flow from said container into the exterior atmosphere. When closed the channel restricts the flow of gas between the venting aperture and exhaust gas aperture.

The present disclosure pertains to a system configured to protect flows in piping systems using minimal spare components. Some embodiments may provide: a first piping subsystem configured to receive a portion of the input flow; a second piping subsystem configured to receive the portion of the input flow by substituting for the first subsystem; a test subsystem configured to detect whether each of the first and second subsystems is able to vent when at least one, in the each subsystem, of a respective pressure and a respective pressure rate satisfies first and second criteria, respectively; and first and second pilots configured to detect a maximum pressure and a maximum pressure rate, respectively, of the portion of the first and second subsystems.

The present disclosure pertains to a system configured to protect flows in piping systems using minimal spare components. Some embodiments may provide: a first piping subsystem configured to receive a portion of the input flow; a second piping subsystem configured to receive the portion of the input flow by substituting for the first subsystem; a test subsystem configured to detect whether each of the first and second subsystems is able to vent when at least one, in the each subsystem, of a respective pressure and a respective pressure rate satisfies first and second criteria, respectively; and first and second pilots configured to detect a maximum pressure and a maximum pressure rate, respectively, of the portion of the first and second subsystems.