Quick Change Valve Trim Assembly

• US 20190285188A1
• Filed: 03/15/2018
• Published: 09/19/2019
• Est. Priority Date: 03/15/2018
• Status: Active Grant

• Current Assignee: Fisher Controls International LLC (Emerson Electric Company)
• Original Assignee: Fisher Controls International LLC (Emerson Electric Company)
• Inventors: Qiu, Yan, Chua, Guo Dong
• Granted Patent: US 10,655,745 B2
• Time in Patent Office: Days
• CPC Class Codes: F16K 1/06 Special arrangements for improving the flow, e.g. special shape of passages or casings
• CPC Class Codes: F16K 1/12 with streamlined valve member around which the fluid flows when the valve is opened
• CPC Class Codes: F16K 1/38 of conical shape
• CPC Class Codes: F16K 1/427 Attachment of the seat to the housing by one or more additional fixing elements
• CPC Class Codes: F16K 1/54 Arrangements for modifying the way in which the rate of flow varies during the actuation of the valve
• CPC Class Codes: F16K 27/0254 with conical shaped valve members
• CPC Class Codes: F16K 27/041 cylindrical slide valves
• CPC Class Codes: F16K 3/246 Combination of a sliding valve and a lift valve
• CPC Class Codes: F16K 3/314 Forms or constructions of slides; Attachment of the slide to the spindle
• CPC Class Codes: F16K 39/022 using balancing surfaces
• CPC Class Codes: F16K 41/02 with stuffing-box ; Sealing rings
• CPC Class Codes: F16K 47/08 for decreasing pressure or noise level and having a throttling member separate from the closure member , e.g. screens, slots, labyrinths
• CPC Class Codes: G05D 16/00 Control of fluid pressure

Abstract

A pressure regulator includes a valve body having a fluid inlet and a fluid outlet connected by a fluid passageway. An orifice is disposed between the fluid inlet and the fluid outlet. A valve seat is disposed within the fluid passageway. A movable valve plug is disposed within the fluid passageway, and the valve plug interacts with the valve seat to selectively open or close the fluid passageway. A cage is disposed in the fluid passageway, the cage surrounds the valve plug, and the cage includes a mechanical stop that limits movement of the valve plug within the cage away from the valve seat.

Claims

1. A pressure regulator comprising:

a valve body having a fluid inlet and a fluid outlet connected by a fluid passageway, and an orifice being disposed between the fluid inlet and the fluid outlet;

a valve seat disposed within the fluid passageway;

a movable valve plug, the valve plug being disposed within the fluid passageway, the valve plug interacting with the valve seat to selectively open or close the fluid passageway, the valve plug including an annular ridge; and

a cage disposed in the fluid passageway, the cage surrounding the valve plug, the cage including a mechanical stop, the annular ridge and the mechanical stop sized to engage one another to thereby limit movement of the valve plug relative to the cage in a direction away from the valve seat.

2. The pressure regulator of claim 1, wherein the mechanical stop is an internal ring having a smaller diameter than a widest diameter of the annular ridge, and wherein the annular ridge is disposed a first distance from the valve seat and the mechanical stop is disposed a second distance from the valve seat, the second distance greater than the first distance.

3. The pressure regulator of claim 2, wherein the cage includes a first region having a first diameter and a second region having a second diameter, the first diameter being larger than the second diameter and both the first and second diameters being larger than the internal ring diameter.

4. A pressure regulator comprising:

a valve body having a fluid inlet and a fluid outlet connected by a fluid passageway, and an orifice being disposed between the fluid inlet and the fluid outlet;

a valve seat disposed within the fluid passageway;

a movable valve plug, the valve plug being disposed within the fluid passageway, the valve plug interacting with the valve seat to selectively open or close the fluid passageway; and

a cage disposed in the fluid passageway, the cage surrounding the valve plug, the cage including a mechanical stop that limits movement of the valve plug relative to the cage away from the valve seat;

wherein the mechanical stop is an internal ring having a smaller diameter than a widest diameter on the valve plug;

wherein the cage includes a first region having a first diameter and a second region having a second diameter, the first diameter being larger than the second diameter and both the first and second diameters being larger than the internal ring diameter; and

wherein the first region is located farther from the valve seat than the second region.

5. The pressure regulator of claim 4, wherein the first region accommodates a piston ring and the second region accommodates a bore seal.

6. The pressure regulator of claim 4, wherein the valve plug includes a balance passage.

7. The pressure regulator of claim 4, wherein the valve seat is one of a welded seat, a bolted seat, a clamped seat, and a hung threaded seat.

8. The pressure regulator of claim 4, further comprising a plug seal retainer, the plug seal retainer securing a plug seal against the valve plug, the plug seal forming a seal between the valve plug and the cage.

9. A trim assembly for a pressure regulator, the trim assembly comprising:

a valve seat;

a valve plug, the valve plug being movable relative to the valve seat, the valve plug interacting with the valve seat to selectively open or close the valve seat, the valve plug including an annular ridge; and

a cage disposed in the fluid passageway, the cage surrounding the valve plug, the cage including a mechanical stop, the annular ridge and the mechanical stop sized to engage one another to thereby limit movement of the valve plug relative to the cage in a direction away from the valve seat and

wherein the annular ridge is disposed a first distance from the valve seat and the mechanical stop is disposed a second distance from the valve seat, the second distance greater than the first distance.

10. The trim assembly of claim 9, wherein the mechanical stop is an internal ring having a smaller diameter than a widest diameter on the valve plug.

11. The trim assembly of claim 10, wherein the cage includes a first region having a first diameter and a second region having a second diameter, the first diameter being larger than the second diameter and both the first and second diameters being larger than the internal ring diameter.

12. A trim assembly for a pressure regulator, the trim assembly comprising:

a valve seat;

a valve plug, the valve plug being movable relative to the valve seat, the valve plug interacting with the valve seat to selectively open or close the valve seat; and

a cage disposed in the fluid passageway, the cage surrounding the valve plug, the cage including a mechanical stop that limits movement of the valve plug relative to the cage away from the valve seat;

wherein the mechanical stop is an internal ring having a smaller diameter than a widest diameter on the valve plug;

wherein the cage includes a first region having a first diameter and a second region having a second diameter, the first diameter being larger than the second diameter and both the first and second diameters being larger than the internal ring diameter; and

wherein the first region is located farther from the valve seat than the second region.

13. The trim assembly of claim 12, wherein the first region accommodates a piston ring and the second region accommodates a bore seal.

14. The trim assembly of claim 12, wherein the valve plug includes a balance passage.

15. The trim assembly of claim 12, wherein the valve seat is one of a welded seat, a bolted seat, a clamped seat, and a hung threaded seat.

16. The trim assembly of claim 12, further comprising a plug seal retainer, the plug seal retainer securing a plug seal against the valve plug, the plug seal forming a seal between the valve plug and the cage.

17. A method of removing a trim assembly from a pressure regulator, the method comprising:

removing a bonnet from a pressure regulator;

pulling on a valve stem that is connected to a valve plug to move the valve plug in relation to a cage until the valve plug engages a mechanical stop on the cage; and

continuing to pull on the valve stem until the valve plug and the cage are extracted from a valve body as a unit; and

forming the mechanical stop by an internal ring having a smaller diameter than a largest diameter of the valve plug;

wherein the cage includes a first region having a first diameter and a second region having a second diameter, the first diameter being larger than the second diameter and both the first and second diameters being larger than the internal ring diameter; and

locating the first region farther from a valve seat than the second region.

18-20. -20. (canceled)