Adjustable pilot operated flow control valve
First Claim
1. A flow control valve for controlling flow through a conduit characterized by an inlet pipe and an outlet pipe comprising:
- a main valve (2) having an inlet 4 and an outlet 7, said main valve operable to throttle fluid flow through a conduit (41, 42);
a pilot valve (3) operable to control a position of the main valve (2), said pilot valve having a control fluid chamber (33), wherein the pressure of control fluid in the control fluid chamber determines a pressure set point of the pilot valve;
a high pressure sensing port (21) disposed in a high pressure region proximate the inlet of the main valve (2), and in fluid communication with the pilot valve (3);
a low pressure sensing port (22) disposed in a low pressure region downstream of the high pressure sensing port (21), and in fluid communication with the pilot valve (3);
means for pressurizing the control fluid in the control fluid chamber (37), said means for pressurizing the control fluid operable from the outside of the conduit after the valve is installed in the conduit.
1 Assignment
0 Petitions
Accused Products
Abstract
A flow control valve including a main valve and a pilot valve for controlling a piston of the main valve. The pilot valve is controlled in part with relatively high pressure fluid ported from a high pressure port of a flow sensor and relatively low pressure fluid ported from a low pressure port of a flow sensor, and also controlled with a control fluid applied to a control plate acting on a compression spring to bias the pilot valve. The pressure in the control fluid is controlled by pressurizing a control fluid reservoir with a mechanism accessible from outside the valve and the piping in which the valve is installed. The flow sensor and the reservoir are preferably disposed within the flange of the valve.
11 Citations
9 Claims
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1. A flow control valve for controlling flow through a conduit characterized by an inlet pipe and an outlet pipe comprising:
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a main valve (2) having an inlet 4 and an outlet 7, said main valve operable to throttle fluid flow through a conduit (41, 42); a pilot valve (3) operable to control a position of the main valve (2), said pilot valve having a control fluid chamber (33), wherein the pressure of control fluid in the control fluid chamber determines a pressure set point of the pilot valve; a high pressure sensing port (21) disposed in a high pressure region proximate the inlet of the main valve (2), and in fluid communication with the pilot valve (3); a low pressure sensing port (22) disposed in a low pressure region downstream of the high pressure sensing port (21), and in fluid communication with the pilot valve (3); means for pressurizing the control fluid in the control fluid chamber (37), said means for pressurizing the control fluid operable from the outside of the conduit after the valve is installed in the conduit. - View Dependent Claims (2, 7, 8)
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3. A flow control valve for controlling flow through a conduit characterized by an inlet pipe and an outlet pipe comprising:
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a main valve (2) having an inlet 4 and an outlet 7, said main valve operable to throttle fluid flow through a conduit (41, 42); a pilot valve (3) operable to control a position of the main valve (2), said pilot valve having a control fluid chamber (33), wherein the pressure of control fluid in the control fluid chamber determines a pressure set point of the pilot valve; a high pressure sensing port (21) disposed in a high pressure region proximate the inlet of the main valve (2), and in fluid communication with the pilot valve (3); a low pressure sensing port (22) disposed in a low pressure region downstream of the high pressure sensing port (21), and in fluid communication with the pilot valve (3); means for pressurizing the control fluid in the control fluid chamber (37), said means for pressurizing the control fluid operable from the outside of the conduit after the valve is installed in the conduit; a flange (5) secured to the main valve;
whereinthe means for pressurizing the control fluid (37) is disposed at least partially within the flange, and a control fluid reservoir (36) disposed within the flange (5);
whereinthe means for pressurizing the control fluid (37) comprises a screw or plunger disposed within the reservoir, with a head accessible from the outer surface of the flange. - View Dependent Claims (4, 5)
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6. A flow control valve for controlling flow through a conduit characterized by an inlet pipe and an outlet pipe comprising:
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a main valve (2) having an inlet 4 and an outlet 7, said main valve operable to throttle fluid flow through a conduit (41, 42); a pilot valve (3) operable to control a position of the main valve (2), said pilot valve having a control fluid chamber (33), wherein the pressure of control fluid in the control fluid chamber determines a pressure set point of the pilot valve; a high pressure sensing port (21) disposed in a high pressure region proximate the inlet of the main valve (2), and in fluid communication with the pilot valve (3); a low pressure sensing port (22) disposed in a low pressure region downstream of the high pressure sensing port (21), and in fluid communication with the pilot valve (3); means for pressurizing the control fluid in the control fluid chamber (37), said means for pressurizing the control fluid operable from the outside of the conduit after the valve is installed in the conduit; and a flange (5) secured to the main valve (2);
whereina bore of the flange forms the inlet (4) of the main valve, and said bore is configured as a Venturi nozzle (20), and the high pressure sensing port (21) is disposed in an upstream face of the flange; and the low pressure region in which the low pressure sensing port (22) is disposed is proximate the outlet of the Venturi nozzle (20).
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9. A flow control valve for controlling flow through a conduit characterized by an inlet pipe and an outlet pipe, said flow control valve comprising:
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a main valve operable to throttle fluid flow through a conduit, said main valve comprising an inlet configured as a Venturi nozzle, an outlet tube with a bore providing a fluid pathway to an aperture in the outlet tube, a piston translatably disposed within the outlet tube to occlude the aperture to a varying extent, and an everting diaphragm operably secured to the piston, and a main valve operating chamber disposed on a side of the everting diaphragm; a high pressure sensing port disposed in a high pressure region of the inlet, and a low pressure sensing pot disposed in a low pressure region of the inlet; a pilot valve having a pilot valve output communicating with the main valve operating chamber, operable to port high pressure fluid to the main valve operating chamber to force the piston to translate within the tube, said pilot valve having a plunger and a diaphragm operable to move the plunger into and out of occlusion with the pilot valve output, and a high pressure chamber on a first side of the diaphragm and a low pressure chamber on a second side of the diaphragm, a biasing plate forming a boundary of the low pressure chamber and positioned to exert a biasing force on the diaphragm, and a biasing spring disposed between the biasing plate and the diaphragm, and a control fluid chamber for applying control fluid to the biasing plate on a side of the plate outside the low pressure chamber; a high pressure port communicating with the high pressure chamber, in fluid communication with the high pressure sensing port in the flange; a low pressure port communicating with the low pressure chamber, in fluid communication with the low pressure sensing port in the flange; a control fluid reservoir disposed in the flange, in fluid communication with the control fluid chamber of the pilot valve, and a mechanism for pressurizing the control fluid reservoir, to thereby pressurize the control fluid in the control fluid chamber; and a high pressure PT port, disposed on the flange, in fluid communication with the high pressure sensing port and a low pressure PT port, disposed on the flange, in fluid communication with the low pressure sensing port.
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Specification