Reduced torque gate valve with roller screw

• US 20030038266A1
• Filed: 08/23/2002
• Published: 02/27/2003
• Est. Priority Date: 08/24/2001
• Status: Active Grant

• Current Assignee: FMC Technologies Incorporated (TechnipFMC, plc)
• Original Assignee: FMC Technologies Incorporated (TechnipFMC, plc)
• Inventors: Glidden, Gregory L., Cain, David E., Hallden, Donald F., Scott, William L.
• Granted Patent: US 6,918,574 B2
• Time in Patent Office: Days
• US Class Current: 251/266
• CPC Class Codes: F16K 3/0254 being operated by particular means
• CPC Class Codes: F16K 31/508 the actuating element being rotatable, non-rising, and driving a non-rotatable axially-sliding element

Abstract

A gate valve is disclosed which comprises a valve body which includes a flow bore that extends completely therethrough and a gate cavity that extends partially therethrough and intersects the flow bore, a bonnet which is connected to the valve body over the gate cavity, a gate which is disposed in the gate cavity across the flow bore and includes a transverse opening that extends completely therethrough, a valve stem which includes a first portion that is connected to the gate and a second portion that extends through the gate cavity, a handwheel, and a roller screw assembly which is connected between the handwheel and the second portion of the valve stem and which converts rotation of the handwheel into translation of the valve stem. In this manner, translation of the valve stem raises or lowers the gate to bring the opening into or out of alignment with the flow bore to either open or close the gate valve, respectively.

Claims

1. A gate valve which comprises:

a valve body which includes a flow bore that extends completely therethrough and a gate cavity that extends partially therethrough and intersects the flow bore;

a bonnet which is connected to the valve body over the gate cavity;

a gate which is disposed in the gate cavity across the flow bore and includes a transverse opening that extends completely therethrough;

a valve stem which includes a first portion that is connected to the gate and a second portion that extends through the gate cavity;

a handwheel; and

a roller screw assembly which is connected between the handwheel and the second portion of the valve stem and which converts rotation of the handwheel into translation of the valve stem;

wherein translation of the valve stem raises or lowers the gate to bring the opening into or out of alignment with the flow bore to either open or close the gate valve, respectively.

2. The gate valve of claim 1, wherein the roller screw assembly comprises:

a roller screw nut which is connected to the handwheel; and

a roller screw shaft which connected to the valve stem;

wherein the roller screw shaft is rotatably received within the roller screw nut.

3. The gate valve of claim 2, further comprising:

a roller thrust bearing which is secured to the roller screw nut; and

a roller adapter shaft which includes a lower portion that is secured to the roller screw nut and an upper portion that is connected to the handwheel;

wherein rotation of the handwheel rotates the roller adapter shaft, the roller screw nut and the roller thrust bearing in unison.

4. The gate valve of claim 3, wherein the roller screw nut includes a radially extending flange which is disposed between the roller thrust bearing and the roller adapter shaft, and the roller screw nut is secured to the roller thrust bearing and the roller adapter shaft through the flange.

5. The gate valve of claim 3, further comprising:

a bonnet cap which is secured to the bonnet;

wherein the roller screw nut, the roller thrust bearing and the lower portion of the roller adapter shaft are positioned in the bonnet cap.

6. The gate valve of claim 5, further comprising a lower roller bearing which is positioned between the roller thrust bearing and the bonnet cap.

7. The gate valve of claim 6, further comprising an upper roller bearing which is positioned between the roller adapter shaft and the bonnet cap.

8. The gate valve of claim 6, further comprising a thrust bushing which is positioned between the lower roller bearing and the bonnet.

9. The gate valve of claim 5, further comprising means for exerting rotational drag on the roller adapter shaft.

10. The gate valve of claim 9, wherein the drag means comprises a packing which is positioned between the roller adapter shaft and the bonnet cap.

11. The gate valve of claim 1, wherein the gate comprises a lower end and an upper end and the opening extends through the gate proximate the lower end.

12. The gate valve of claim 11, further comprising:

a first backseat surface which is integral with the valve stem;

a second backseat surface which is integral with the bonnet;

wherein translation of the valve stem from the closed position to the open position will bring the first and second backseat surfaces into engagement to thereby form a backseat seal between the valve stem and the bonnet.