A valve includes a basic body, control spool, sealing ring, and control cover. The control spool is received in the basic body to be movable along a longitudinal axis. The basic body includes a counter-sealing surface, connecting channel, and tank channel having at least one first annular groove surrounding the control spool. The control cover and at least one end face of the control spool facing toward the longitudinal axis delimits, at least in part, a control space. The control cover includes a sealing surface that abuts the counter-sealing surface of the basic body. At least one of the sealing surface and the counter-sealing surface includes a sealing groove that surrounds the control space in ring-like fashion. The sealing ring is received in the sealing groove. The connecting channel opens out into the tank channel and into the sealing groove.

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.

An irrigation management system is disclosed and positionable in-line with an irrigation pipe for monitoring and controlling a flow of fluid therethrough. In at least one embodiment, the system provides an inlet pipe and an opposing outlet pipe in serial fluid communication with the irrigation pipe. At least one fluid control valve is in serial fluid communication between the inlet pipe and outlet pipe for selectively controlling the flow of fluid therebetween. The fluid control valve provides a main valve and a hydraulic actuator for selectively moving the main valve between open and closed positions. The hydraulic actuator is also in serial fluid communication between a pair of actuator valves for moving the hydraulic actuator between open and closed positions. The system also provides at least one sample collection tank configured for temporarily storing a volume of fluid diverted from the irrigation pipe in order to be tested.

A fluid distribution system includes a mass flow controller and a first manifold assembly. The mass flow controller includes first and second end ports each extending from a lower end of the mass flow controller, proximate corresponding first and second sides of the mass flow controller, for lateral flow through the mass flow controller from the first end port to the second end port. The first manifold assembly includes a first end connection coupled to the first end port of the mass flow controller. The first manifold assembly includes a first manifold body extending parallel to the first side of the mass flow controller, and a plurality of first valve subassemblies retained in the first manifold body and arranged across a plane extending substantially parallel to the first side of the mass flow controller, with valve movement perpendicular to the first side of the mass flow controller.

Systems, devices, and methods of modulating a pressure relief valve are provided. A modulating pilot valve assembly can receive an inlet pressure of an inlet of a pressure relief valve and can receive a dome area pressure of a dome area of the pressure relief valve. The modulating pilot valve assembly and the pressure relief valve can be configured to maintain a leak-tight seal until reaching a pilot valve pressure set point, at which the modulating pilot valve assembly instantly reduces the dome area pressure instantly, via a biasing mechanism of the modulating pilot valve assembly causing the pressure relief valve to initially open and thereafter to progressively reduce the dome area pressure in proportion to an increase in the inlet pressure and to cause the pressure relief valve to open in proportion to the increase in the inlet pressure.

A manifold body includes a body block, with one or more end connections each extending laterally outward from a first surface of the body block, one or more lower valve cavities each recessed laterally inward from the first surface, one or more upper valve cavities each recessed laterally inward from the first surface and connected with a corresponding one of the one or more lower valve cavities by a vertically extending second passage, one or more lower end ports each extending laterally outward from a second surface of the body block and connected with a corresponding one of the one or more lower valve cavities by a laterally extending third passage, and one or more upper end ports each extending laterally outward from the second surface and connected with a corresponding one of the one or more upper valve cavities by a laterally extending fourth passage.

A waterproof cover includes an operation unit for pressing a manual button of a solenoid valve main body. The operation unit includes a flexible cap, a pin guide interposed between the cap and the solenoid valve main body, and an operation pin that is inserted in guide hole of the pin guide so as to be displaced freely. The cap includes a flexible pressing portion for a pressing operation. One end of the operation pin is in contact with or close to the pressing portion, and the other end of the operation pin is in contact with the manual button.

A valve with an internal member is disclosed which allows exhaled carbon dioxide to escape from a breathing circuit when the circuit gas pressure drops below a threshold pressure. The valve operates by occluding one or more ports under a relatively high pressure and opening the one or more ports under a relatively low pressure. The internal member is attached to the body of the valve at two or more locations on the internal member. The internal member moves in a direction perpendicular to the gas flow through the valve.

A lubrication pumping system for an oil lubricated engine is provided that includes a pump with an outlet and inlet. A relief valve is included having a housing with a multidimensional bore having a first diameter section axially intersecting with a second different diameter section. Slidably mounted in the first section is a spring biased primary piston have a first landing for metering flow between a pump discharge connection and a pump inlet connection. A secondary piston is provided in a second different diameter section of the valve housing bore. The inventive system allows for multiple modes of operation of oil pressure versus engine speed relationships by control of the pilot pressure to minimize parasitic loads exerted by the oil pump on the vehicle engine.

A control valve for a fluid treatment apparatus is provided, including a valve body having a control portion and a treatment portion, the portions being separated from each other so that fluid in the control portion is isolated from fluid in the treatment portion. The treatment portion includes a plurality of piston valves reciprocating in corresponding openings defined in a corresponding number of cylinders for controlling water to be treated in the apparatus. Each of the cylinders has a plurality of peripherally spaced, vertically-extending guide ribs configured for facilitating engagement of the piston valves with the openings and for reducing unwanted cavitation.