Control valve with low noise and enhanced flow characteristics

• US 6,973,941 B2
• Filed: 11/03/2004
• Issued: 12/13/2005
• Est. Priority Date: 12/19/2002
• Status: Active Grant

• Current Assignee: Fisher Controls International LLC (Emerson Electric Company)
• Original Assignee: Fisher Controls International LLC (Emerson Electric Company)
• Inventors: Baumann, Hans D.
• Primary Examiner(s): FOX, JOHN C
• Application Number:
  US10/980,726
• Publication Number:
  US 20050061375A1
• Time in Patent Office: 405 Days
• Field of Search: 137/625.3, 137/625.33, 137/625.37, 137/625.38, 251/362
• US Class Current: 137/625.37
• CPC Class Codes: F16K 3/267 Combination of a sliding valve and a lift valve F16K3/262, F16K3/265 take precedence
• CPC Class Codes: F16K 47/04 for decreasing pressure or noise level, the throttle being incorporated in the closure member
• CPC Class Codes: Y10T 137/86791 Piston
• CPC Class Codes: Y10T 137/86807 Sequential opening or closing of serial ports in single flow line

Abstract

A control valve that reduces noise and controls flow includes a slotted cylindrical skirt and/or a tapered metal ring. The metal ring has a tapered external surface for engaging a matching tapered bore within a valve housing. One embodiment is directed to a control valve including a housing defining a central orifice in fluid in communication with an inlet port and an outlet port, and a movable valve plug assembly having a skirt portion slidably engaged within the central orifice to control fluid flowing through the housing. The skirt portion defines a plurality of openings, which can be slots, to gradually control the flow of fluid through the housing while reducing cavitation. A method of controlling fluid flow in a process includes receiving fluids via an inlet port of a control valve, and controlling the flow of the fluid via a movable skirted valve plug with a plurality of tapered slots.

Claims

1. A control valve comprising:

a valve housing defining an inlet port and an outlet port;

a metal ring defining a central orifice and being permanently attached to the valve housing, the metal ring connecting the inlet port and the outlet port and including a tapered external surface for engaging a matching tapered bore within the valve housing; and

a movable valve plug disposed between the inlet and the outlet, the moveable valve plug having a cylindrical skirt portion slidably engaged within the central orifice, the cylindrical skirt defining a plurality of tapered openings cooperating with the inlet port and outlet port, the cylindrical skirt portion including a lower terminating end incorporating one or more concave openings wherein at least one of the plurality of openings is a slot that expands from the outside diameter of the cylindrical skirt portion at an angle of no less than approximately 8 degrees and no more than approximately 30 degrees.

3. The control valve of claim 1 wherein the metal ring has a smallest diameter of the tapered external surface at a lower terminating end and wherein the terminating end further incorporates a thinned and deformable portion capable of being pressed against a portion of the housing to secure the orifice to the valve housing.

4. The control valve of claim 1 wherein the taper of the external surface is at least approximately 0.5 degrees.

5. The control valve of claim 1 wherein the taper of the external surface is less than approximately 6 degrees.

6. The control valve of claim 1 wherein angling the taper of the external surface provides a fluid tight press fit between the metal ring and the tapered bore of the housing.

2. A control valve comprising:

a valve housing defining an inlet port and an outlet port;

a metal ring defining a central orifice and being permanently attached to the valve housing, the metal ring connecting the inlet port and the outlet port and including a tapered external surface for engaging a matching tapered bore within the valve housing; and

a movable valve plug disposed between the inlet and the outlet, the moveable valve plug having a cylindrical skirt portion slidably engaged within the central orifice, the cylindrical skirt defining a plurality of tapered openings cooperating with the inlet port and outlet port, the cylindrical skirt portion including a lower terminating end incorporating one or more concave openings such that the plurality of tapered openings are slots having two or more lengths wherein the lengths progressively increase towards the lower terminating end.

7. The control valve of claim 2 wherein the metal ring has a smallest diameter of the tapered external surface at a lower terminating end and wherein the terminating end further incorporates a thinned and deformable portion capable of being pressed against a portion of the housing to secure the orifice to the valve housing.

8. The control valve of claim 2 wherein the taper of the external surface is at least approximately 0.5 degrees.

9. The control valve of claim 2 wherein the taper of the external surface is less than approximately 6 degrees.

10. The control valve of claim 2 wherein angling the taper of the external surface provides a fluid tight press fit between the metal ring and the tapered bore of the housing.