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In-line, pilot-operated, differential area, poppet type valve provides both automatic relief of a tank at a precise over-pressure and remote control of tank venting. Relief and vent operations are separate functions incorporated in an integral valve package.
Modified solenoid valve reduces valve seat loading by eliminating off-center operation of the armature, reducing the poppet size and spring-cushioning its impact, and reducing armature impact with a poppet guide stop.
Valve regulates the flow of a fluid over the limits from full flow in one direction to full flow in the opposite direction. At the midpoint valve position both flow paths are closed. Gradually increasing port size on both flow paths results in good throttling characteristics.
Electronic circuit connected to solenoid valve coils visually indicates the position of the valve stem. Transient suppression is provided to prevent damaging voltage spikes.
Valve with embedded fine particles of diamond in the metal surface of the valve seat resists galling, corrosion, erosion, and cold welding. Diamond powder has an average particle diameter of 0.01 micron and is used with a standard fine diamond polishing compound.
Basic relief valve has added safety relief valve capability that relieves overpressure before failure can occur. It may be installed in inaccesible areas with a high degree of reliability, constructed from a variety of materials, and adapted to the user's specific application.
Bistable control valve is selectively switched by direct application of an electrical field to divert fluid from one output channel to another. Valve is inexpensive, has no moving parts, and operates on fluids which are relatively poor electrical conductors.
Ball valve design incorporates modular construction in easy-to-install, easy-to-replace cartridge housing, and a system of cams to lift upstream and downstream seals away from the ball during rotation. Tests conducted on nitrogen tetroxide prove new valve to be more efficient than previous models in preventing leakage.
Valve leakage due to contaminant entrapment and chattering is effectively minimized by a metallic poppet-and-seat check valve designed for use in extreme environmental and fluid temperature conditions.
Leakage elimination occurs by increasing pressure on poppet seat, heating poppet plunger or cooling valve body, and then exerting force between 4.45 and 44.5 kN at poppet seat interface. Valves are useful in handling of corrosive fluids.
Prototype liquid-fuel valve performs on-off and throttling functions in vacuum without component cold-welding or excessive leakage. Valve design enables simple and rapid disassembly and parts replacement and operates with short working stroke, providing maximum throttling sensitivity commensurate with good control.
Proportional pulsed pilot valve using conventional efficient solenoid valve for pilot stage provides proportional thrust control for cold gas thrusters with zero leakage of main stage.
Fabrication and acceptance testing, fluorine compatibility testing, valve refurbishment and testing, environmental testing, and design of space storable oxidizer valve
Apollo service propulsion system rocket engine bipropellant valve improvement program - valve design guide and oxygen-hydrogen technology
Modification of spring-loaded swing-check valve for solenoid operation provides low-vacuum swing-check valve which can be operated remotely.
Threaded rod, mounted in tubular housing which is flanged and expandable at one end, removes valve lifter after removal of valve covers and push rods.
Combination of translating sleeve throttle valve and conventional poppet valve provides capability of shutting off flow completely by poppet and sleeve control of the rate of flow. Integration of the two concepts can be accomplished without difficulty and in a manner that requires a minimum of development.
Development of mechanical device to reduce possibility of damage to motor driven needle valve is discussed. Mechanical clutch is employed to allow slippage when needle valve reaches limit of travel. Operation of system for various conditions is described.