280results about "Fluid pressure control with auxillary non-electric power" patented technology

A flow control device may include an inlet for passing fluid into the device, an outlet for passing fluid from the device, a pneumatic pressure controlling portion, a fluid flow control valve actuated by pneumatic pressure supplied via the pneumatic pressure controlling portion, a flow meter configured to measure flow rate of the fluid, and a controller configured to control the pneumatic pressure controlling portion at least according to the flow rate measured by the flow meter. Actuation of the fluid flow control valve may cause adjustment of the flow rate.

The present invention provides a method and apparatus for substantially eliminating destructive transients of pressure or flow rate which can degrade the efficiency and useful lifetime of chromatography columns. The present invention enables a substantially constant flow of mobile phase liquid to be maintained through the chromatography system by eliminating the flow blockage interval associated with the actuation of sample injection valves. The present invention further provides a method to reduce the pressure and flow rate transients associated with pressurization of the sample loop contents when the sample loop is introduced to chromatography system delivery pressure.

A valve with a shuttle for use in a flow management system is capable of bypassing a backflow.

A starter air valve assembly includes a valve body, a flow control valve, a rate control servo mechanism, and a valve actuator. The valve body defines a flow passage having at least an inlet port and an outlet port. The valve is disposed at least partially within the flow passage and is moveable between an open position and a closed position. The rate control servo mechanism is adapted to receive pressurized fluid and is configured, upon receipt of the pressurized fluid, to supply a controlled flow of the pressurized fluid. The valve actuator is coupled to the valve and is in fluid communication with the rate control servo to thereby receive the controlled flow of the pressurized fluid. The valve actuator is configured, upon receipt of the controlled flow of the pressurized fluid, to move the valve between the closed position and the open position at a substantially controlled rate.

The invention provides a method for controlling goaf air leakage in the exploitation process of a shallow buried close-range coal seam. The method mainly comprises technologies such as plugging of earth surface air leaking fractures and detecting and plugging of downhole air leaking channel, namely, first, the widths of earth surface mining-induced fractures are measured and the speed of fracture air leaking is calculated; the fractures with the widths and the air leaking air speeds being out of gauge are plugged, an air inlet roadway and an air outlet roadway which are difficult to cave by a roof in a goaf is caved by a manual way, and air leaking toward the goaf is reduced; next, a beam tube monitoring system is used for monitoring the concentration of O2 in the goaf, and whether air leaking exists or not in the goaf is judged according to the concentration of O2; then, a tracer gas method is used for detecting air leaking channels of downhole coal pillars, the air inlet roadway, the air outlet roadway and the like, and corresponding plugging measures are adopted; and at the time of plugging, a fan-air-window combined pressure regulating method is used for balancing air pressure of the goaf and a working face, goaf air leaking is reduced, and coal spontaneous combustion in the goaf is avoided.

A system for hydraulically managing fluid pressure in a fluid distribution system between pressure set points includes a main valve having a fluid inlet and outlet. The main valve is configured to open to increase fluid flow therethrough and to close to reduce the fluid flow therethrough. A variable orifice assembly is coupled to the main valve and has fluid apertures formed in a housing thereof to create a fluid flow pathway therebetween. A valve stem is variably positioned within the housing to alter the fluid flow between the fluid apertures. A first control pilot is in fluid communication with the main valve and a first fluid aperture of the variable orifice assembly. A second control pilot is in fluid communication with the main valve and a second fluid aperture of the variable orifice assembly. The valve position and fluid flow are variable as the main valve opens and closes.

The invention discloses a pressure control system of a transmission chamber and a method thereof. The transmission chamber is equipped with a charging air passage and an evacuating air passage, wherein the evacuating air passage is provided with an evacuating speed control device, and pressure in the transmission chamber is controlled through controlling evacuating speed of the evacuating air passage in the transmission chamber. The evacuating speed control device is connected with a controller, the transmission chamber is equipped with a pressure sensor connected with the controller, firstly detecting pressure signals in the transmission chamber, then comparing the pressure signals with the set pressure parameters, and on-line adjusting the evacuating speed of the evacuating air passage in real time through closed-loop control algorithms such as PID and the like, finally, the purpose of control pressure in the transmission chamber is achieved. Besides, the system is stable in pressure control and low in nitrogen consumption.

There is provided a pilot valve (50), suitable for use in water and gas supply systems, the valve including biassing means (57), to control a gate (55), for controlling fluid flow through a control chamber (51), and a second chamber (52), which is sealed by a diaphragm (53), the second chamber (52), in use, receiving a control pressure for controlling the operation of the gate (55), such that an increase in control pressure acts to reduce fluid flow through the gate (55). The side of the diaphragm (53), against which the control pressure is not applied, is in fluid communication with the control chamber (51).

The invention provides a chamber pressure control method, which comprises: step 100, acquiring air delivery target flow required when a chamber is in a target pressure according to a corresponding relationship between the pressure of the chamber and the air delivery flow; and step 200, setting the air delivery target flow as a flow setting value of a mass flow controller, wherein the mass flow controller implements air delivery operation on the chamber based on the flow setting value and controls the pressure of the chamber within the target pressure range. The method for controlling the pressure of the chamber also comprises a step of acquiring the corresponding relationship between the pressure of the chamber and the air delivery flow. In addition, the invention also provides a chamber pressure control device, a chamber pressure control system using the method and the chamber pressure control system using the device. An expensive pressure control valve is replaced by adopting the cheaper mass flow controller and the simple control step, and the cost of the process/equipment is saved while effectively controlling the pressure of the chamber.

Cartridge-style fluid control devices are provided that are static pressure independent and capable of repeatable, reliable, particulate insensitive performance in service conditions typical of downhole intervention environments.

A low pressure and high-low temperature test box capable of controlling humidity comprises a test box body (1), a first heater (2) and a first evaporator (3) which are installed in the test box body (1), a humiture sensor (4) for detecting the humiture inside the test box body (1) and a vacuum manometer (5) for detecting the pressure inside the test box body (1) which are both installed on the test box body (1), an air circulation device (6) for circulating the air inside the test box body (1), and a humidity adjusting device (7) which is connected to the test box body (1) and used for adjusting the humidity inside the test box body (1). A vacuum pump (8) for vacuumizing the test box body (1) is also provided on the test box body (1).

There are provided a flow control valve and a flow control device suitable for allowing flow control of a fluid with high accuracy. Diaphragms 8 and 9 are mounted to upper and lower openings, respectively, of an air chamber 6. The upper diaphragm 8 and the lower diaphragm 9 are connected by a connecting shaft 10 and have pressurized surfaces with different areas that receive pressure of the air chamber 6. This causes a difference between forces applied to the two diaphragms 8 and 9, and the difference causes the connecting shaft 10 and a valve body 2 mounted to an outer surface of the lower diaphragm 9 to slide and be separated from a valve seat 23.

An inflating module adapted to an inflatable object includes an air pump assembly selectively operable to deflate and inflate the inflatable object and a supplemental air pressure providing device automatically activated to provide supplemental air pressure to the inflatable object when the air pressure of the inflatable object is down and below a predetermined level so as to maintain air pressure of the inflatable object in a predetermined range.

A gas pressure regulator has an inlet for connection to an upstream gas line for flow of gas into the regulator under pressure and an outlet for connection to a downstream gas line for flow of gas out of the regulator at a reduced pressure. A pilot mechanism delivers a desired pilot gas pressure through a pilot passage. A main valve mechanism regulates the flow of gas through a main flow passage connecting the inlet and outlet of the regulator. The regulator has a piston chamber, and a piston operatively connected to the main valve mechanism and movable in the piston chamber. The main valve mechanism has a passageway between the piston chamber and the pilot passage whereby the pilot gas pressure is adapted to move the piston and thereby position the main valve mechanism to regulate the gas pressure at the outlet of the regulator.

A dual flow check valve having a check valve body with an interior chamber. There is a first inlet in open communication with the chamber and a second inlet in open communication with the chamber. There is also an outlet in open communication with the chamber. A pressure responsive valve element to permit one-way flow of a fluid through the first inlet into the chamber is mounted in the body.

A pressure regulating valve, in particular a proportional pressure regulating valve, includes a valve body (1) with at least a pump connection (P), a use connection (A) and a tank connection (T). A piston (19), capable of being displaced by a controllable actuating device (29), is guided in the valve body (1). At the periphery of the piston, a recess (45) is formed and defines a peripheral annular gap (47) delimited by the control edges (49, 51) of the piston (19). In the piston (19), a passage (55) provides fluid communication between the front surface of the piston (19), subjected to the use connection (A) pressure, and the rear surface (35) of the piston (19), adjacent to a pressure chamber (37) located behind. The passage (55) of the piston (19) has, in the region proximate to the piston front surface, a restriction zone (57). In a region away from the restriction zone (57) towards the rear of the piston surface (35), an orifice (59) faces the peripheral annular gap (47), and has a second restriction zone (61).

A pressure control valve is provided, which can variably control the set pressure of a relief valve in accordance with pilot signal pressure that is controlled in an operator's seat and so on when the set pressure of the relief valve required in a replaced working device is changed. The pressure control valve includes a sleeve having an inlet port and a tank path, a poppet opening/closing a flow path between the inlet port and the tank path, a poppet spring elastically supporting the path between the inlet port and the tank path in a closed state, a valve sheet installed to face the poppet so that a set pressure is formed in a pressure chamber of the sleeve, a pilot poppet draining the hydraulic fluid in the pressure chamber to the hydraulic tank when high pressure that exceeds the set pressure is generated in the pressure chamber, a pilot poppet spring elastically supporting the path of the valve sheet in a closed state, a plug coupled to the sleeve and having a pilot port to receive the pilot signal pressure from an outside, a main piston slidably coupled within a guide coupled to the plug to variably control the set pressure in the pressure chamber in accordance with the pilot signal pressure, and a control plug movably coupled to the guide to control a set pressure of a spring supporting the main piston.

Control systems include various combinations of pressure regulators, pilots, and pressure stabilizers to provide systems with adjustable deadbands for over pressure protection, adjustable deadbands for under pressure protection, adjustable deadbands for both over pressure and under pressure protection, pressure assisted closure for over pressure protection, pressure assisted closure for under pressure protection, pressure assisted closure for both over pressure and under pressure protection, or spring assisted closure for over pressure and under pressure protection.