Abstract: A spring-operated relief valve can include an adjustable main spring to bias the valve closed and a load cell that is configured to measure a force exerted by the main spring. Measurements from the load cell can be used to determine a set or crack pressure in the spring-operated relief valve, and to monitor operation of the spring-operated relief valve.

Abstract: A pilot-operated relief valve assembly can include a relief valve, and a pressure detection assembly. A valve lift factor or indicator of relief flow can be determined based on pressure measurements gathered by the pressure detection assembly.

Abstract: A clamp assembly to secure a yoke to a valve body of a knife gate valve is provided. The clamp assembly can include a bolt that is configured to extend through a first bushing, a first spring member, a first side wall of the yoke, the valve body, a second side wall of the yoke, a second spring member, and a second bushing. The clamp assembly can be configured to pin the yoke to the valve body, apply a pressure-containing preload to the valve body via the first and second bushings, and compress the first spring member between the first bushing and the first side wall of the yoke and the second spring member between the second bushing and the second side wall of the yoke.

Abstract: A flow arrangement for a pressure relief valve assembly can include a bypass flow path extending from a pressure source to a dome of a relief valve. The bypass flow path can include a valve that is configured to open and close the bypass flow path based on pressure at the pressure source or the dome, or a pressure difference between the pressure source and the dome.

Abstract: A flow arrangement for a control valve can include a plurality of flow-control components that are movable relative to each other and that define at least part of a flow path from a pressure source to a dome of a pressure relief valve. The flow-control components can be movable relative to each other in response to system pressure to selectively increase or decrease the flow capacity of the flow path. In some cases, flow capacity can be increased or decreased during initial loading of the dome, at low pressures, or at higher pressures.

Abstract: Embodiments of the invention provide a knife gate valve for flow along a flow path. The knife gate valve can include a body structure that includes a gate passage, a gate disposed to move within the gate passage between open and closed positions to selectively open or close a fluid aperture, and a gate seat configured to engage a free end and lateral edges of the gate. A transverse element can be formed from resilient material and can extend laterally across the gate passage to form a seal with a first side of the gate and with the gate seat.

Abstract: A pilot-operated relief valve assembly can include a relief valve, and a pressure detection assembly. A valve lift factor or indicator of relief flow can be determined based on pressure measurements gathered by the pressure detection assembly.

Abstract: A clamp assembly to secure a yoke to a valve body of a knife gate valve is provided. The clamp assembly can include a bolt that is configured to extend through a first bushing, a first spring member, a first side wall of the yoke, the valve body, a second side wall of the yoke, a second spring member, and a second bushing. The clamp assembly can be configured to pin the yoke to the valve body, apply a pressure-containing preload to the valve body via the first and second bushings, and compress the first spring member between the first bushing and the first side wall of the yoke and the second spring member between the second bushing and the second side wall of the yoke.

Abstract: A fluid flow control device includes a valve body forming a channel defining a fluid flow path extending from an inlet to an outlet, a shaft having a first portion and a second portion, a flow control member coupled to the first portion of the shaft, and a bearing comprising an elongated body having a first end, a second end, an inner surface defining an interior volume, and an outer surface. The bearing is dimensioned to accommodate the shaft in the interior volume and includes at least one opening extending between the inner surface and the outer surface and at least one elongated channel formed on the outer surface. The elongated channel extends a length between the first end and the second end of the elongated body.