摘要:
A valve device for controlled pressurization of a pressure fluid system (35). The device comprises two coaxial valve bodies (9, 13), one (11) for controlling flow communication between inlet port (5) and outlet port (6) and the other (9) for controlling flow communication between outlet port (6) and drain port (7). The coaxial build-up gives short and direct channels and thus small dimensions for a given flow capacity.
摘要:
Methods and apparatus for bypassing a positioner in an active control loop are described. An example actuator assembly includes a pneumatic actuator and a transfer station. The transfer station includes a body defining flow paths that enable fluid to flow between a supply pressure, a valve positioner, and the pneumatic actuator and between the supply pressure and the pneumatic actuator to bypass the valve positioner without disrupting a process loop including the valve positioner. The transfer station also includes a plurality of fluid flow control devices to control the fluid flow through the flow paths.
摘要:
An aircraft gas transport system (110) includes a high pressure gas supply line (115) having a supply valve (120). The gas transport system also includes an equilibrium gas line (150) joined at junctions with the high pressure gas supply line upstream and downstream from the supply valve, and in flow communication with the high pressure gas supply line. The equilibrium gas line has an equilibrium valve (140) and a flow restrictor (135). The equilibrium valve has an exit orifice (173), and the flow restrictor is offset from the exit orifice of the equilibrium valve. A method for pressurizing a gas transport system (110) after a flow of gas through the gas transport system has been prevented (400) comprises: opening (410) an equilibrium valve (140) while maintaining a supply valve (120) closed to allow a flow of gas (GFA) through a flow restrictor (135) that controls a rate of change of a pressure downstream of the equilibrium valve; determining (420) that the pressure downstream of the equilibrium valve or supply valve is stabilized; and opening (430) the supply valve to provide a flow of gas (GFB) through the supply valve at an operating pressure.
摘要:
A soft start valve device (21) is proposed which has a main valve (24) which controls the fluid connection between a primary channel (1) and a secondary channel (2). In order to switch over the main valve (24) into the open position, an opening force is exerted on the valve. In an operating mode that is controlled by a secondary pressure, said force is derived from the secondary pressure which prevails in the secondary channel (2) and, in a time-controlled operating mode, is derived from a pressure medium which flows through a throttling device (39). A particular advantage results from the fact that the two operating modes are carried out simultaneously in a superimposed manner.
摘要:
The invention relates to a valve device (6) which is equipped with a soft start valve (21) in order to provide a soft start function. Said soft start valve (21) comprises main valve means (25) which are positioned to selectively block or release the connection between a primary channel (4) subjected to a primary pressure, and a secondary channel (1). Also, the soft start valve is positioned so that the secondary channel (1) is subjected, at least initially, to lower soft start pressure than the primary pressure which is generated in a soft start channel (2). A control slide (33) of the main valve means (25) is positioned so that it controls the connection between the secondary channel (1) and the soft start channel (2) or the primary channel (4) and comprises an actuation surface (57) which is subjected to soft start pressure for changing the control slide (33).
摘要:
Bei einer Softstartvorrichtung für Druckluftsysteme mit einem Primäreinlass (P1), an dem Druckluft unter Primärdruck zuführbar ist, wobei der Primäreinlass (P1) mit einem, mit wenigstens einem Verbraucher koppelbaren Sekundärauslass (P2) über eine Ventilschaltung verbunden ist, an dem Druckluft unter Sekundärdruck abführbar ist, wobei der Sekundärdruck kleiner oder gleich dem Primärdruck ist, wobei zwischen Primäreinlass (P1) und Sekundärauslass (P2) ein Hauptventil vom Typ 2/2-nc (normaly closed) eingeschaltet ist, das mittels eines Bypasses (17) umgehbar ist, wobei im Bypass (17) eine Drosseleinrichtung (13) eingeschaltet ist, wobei Hauptventil (WV5) und Drosseleinrichtung (13) zusammen mit weiteren Ventilen (WV1, WV2, WV3, WV4; WV6; RV) der Ventilschaltung miteinander verschaltet sind und die Ventilschaltung in eine derartige Standard-Entlüftungsschaltstellung versetzbar ist, dass der Sekundärauslass (P2) entlüftet wird, sind die Ventile (WV1, WV2, WV3, WV4, WV5; WV6; RV) der Ventilschaltung derart miteinander verschaltet, dass zusätzlich zur Standard-Entlüftungsschaltstellung mehrere weitere Entlüftungsschaltstellungen möglich sind, wobei sich jeweils eine der weiteren Entlüftungsschaltstellungen ergibt, wenn bei dem normalerweise die Standard-Entlüftungsschaltstellung hervorrufenden Betätigungsvorgang ein beliebiges einzelnes der vorhandenen Ventile (WV1, WV2, WV3, WV4, WV5; WV6; RV) eine Fehlfunktion aufweist.
摘要:
A progressive-starting unit for pneumatic circuits comprises a line inlet (112) and a line outlet (211) interconnected with each other by a regulating valve (212) that is piloted by a pneumatic piloting inlet (213). The piloting inlet is controlled by the outlet (226) of a progressive-starting device (216) having an inlet (217) connected upstream of said regulating valve (212). In this manner a progressive-starting unit is obtained which is insensitive to the conditions downstream of its line outlet.