Downhole ball dropping apparatus

• US 20040055753A1
• Filed: 09/24/2002
• Published: 03/25/2004
• Est. Priority Date: 09/24/2002
• Status: Active Grant

• Current Assignee: Baker Hughes Incorporated (Baker Hughes Company)
• Original Assignee: Baker Hughes Incorporated (Baker Hughes Company)
• Inventors: Davis, John P., Lynde, Gerald D.
• Granted Patent: US 7,100,700 B2
• Time in Patent Office: Days
• US Class Current: 166/318
• CPC Class Codes: E21B 21/10 Valve arrangements in drilling-fluid circulation systems
• CPC Class Codes: E21B 34/08 responsive to flow or pressure of the fluid obtained E21B34/10 takes precedence
• CPC Class Codes: E21B 34/142 unsupported or free-falling elements, e.g. balls, plugs, darts or pistons

Abstract

A ball release mechanism is mounted near the intended seat. The ball or balls are kept out of the circulating stream. High circulation rates followed by curtailment of circulation places an outlet port in position to allow the ball or balls to be pushed out by a spring. The spring or one of the balls prevents the return of an ejected ball back into the protected pocket. The ball is delivered to the seat without circulation.

Claims

1. A ball dropping apparatus, comprising:

a housing having an uphole and a downhole end and a passage through it;

at least one obstructing member mounted in said housing;

said obstructing member selectively movable from an initial position where it is located outside of said passage to an obstructing position in said passage.

2. The apparatus of claim 1, further comprising:

a seat in one of said passage and a connected housing to the ball dropping apparatus, said obstructing member allowing pressure buildup at said uphole end of said housing when it is located on said seat.

3. The apparatus of claim 1, further comprising:

said obstructing member is selectively released by virtue of flow through said passage.

4. The apparatus of claim 3, wherein:

said obstructing member is selectively released only by the onset and subsequent cessation of flow through said passage.

5. The apparatus of claim 1, wherein:

said obstructing member in said initial position is disposed in a side compartment selectively accessible to said passage.

6. The apparatus of claim 5, further comprising:

a selectively movable carrier to hold said obstructing member in said side compartment, in a first position, and to allow release of said obstructing member from said side compartment, when placed in a second position.

7. The apparatus of claim 6, wherein:

said carrier further comprises a flow passage therethrough and wherein a primary seat is mounted in one of said flow passage and a housing connected to the ball dropping apparatus to receive said obstructing member.

8. The apparatus of claim 6, wherein:

said carrier is biased in a direction where said obstructing member will be allowed to exit said side compartment.

9. The apparatus of claim 8, wherein:

said carrier is initially secured to said housing with said bias overcome.

10. The apparatus of claim 9, wherein:

said carrier is mounted in said passage;

said initial securing of said carrier is broken with flow through said flow passage.

11. The apparatus of claim 10, wherein:

said obstructing member remains trapped in said side compartment while flow through said passage overcomes said bias on said carrier.

12. The apparatus of claim 11, wherein:

said obstructing member is released from said side compartment when said bias on said carrier shifts it, upon cessation of flow through said passage.

13. The apparatus of claim 12, wherein:

said carrier comprises an outlet opening that shifts into alignment with said obstructing member as a result of its movement under said bias.

14. The apparatus of claim 12, wherein:

said carrier is locked into position after being shifted by said bias.

15. The apparatus of claim 14, wherein:

said bias on said carrier comprises a spring protected from said passage by a sleeve, said sleeve initially covers a detent in said housing, whereupon when said sleeve is biased against said carrier to move it in a first direction, said detent emerges from said housing into said passage to prevent significant movement of said carrier in a second direction opposite said first direction.

16. The apparatus of claim 5, wherein:

said obstructing member is biased toward said passage from within said side compartment.

17. The apparatus of claim 6, further comprising:

a spring in said side compartment, said spring preventing reentry of said obstructing member into said side compartment.

18. The apparatus of claim 6, wherein:

said at least one obstructing member comprises a plurality of balls; and

a second of said balls prevents a first of said balls, that exits said side compartment, from reentering.

19. The apparatus of claim 2, wherein:

said obstructing member enters said passage within 1 meter of said seat.

20. The apparatus of claim 19, wherein:

said obstructing member comprises a ball; and

said housing comprises a backup seat for use if said ball fails to hold pressure against said seat.