Watermelon mill with replaceable cutting structure

Patent metadata

Field	Value
Publication number	US-10081997-B2
Application number	US-201514944995-A
Country	US
Kind code	B2
Filing date	Nov 18, 2015
Priority date	Nov 18, 2015
Publication date	Sep 25, 2018
Grant date	Sep 25, 2018

Abstract

A watermelon mill has a cutting structure mounted on a removable sleeve. The mandrel can be in two pieces threaded together to trap a ring or lug extending internally from the sleeve. Alternatively the sleeve can serve as a coupling holding together opposed threaded components that then make up the mandrel. The mandrel can have a radial external shoulder to act as a sleeve travel stop and another sleeve can be pushed into the first sleeve that has the cutting structure on it for proper axial fixation. The second sleeve that does not have cutting structure is pushed into position by making up an adjacent pin and box combination at a nearby connection to the cutting structure. What results is a flexible assembly that assembles without welding and retains greater flexibility in the larger sizes due to the assembly method. The sleeve can be tossed when the cutting structure is spent or redressed and remounted for another use.

First claim

We claim:

1. A milling tool for subterranean use, comprising:
a mandrel having a mandrel axis and multiple selectively separable components;
a sleeve having a sleeve axis coinciding with said mandrel axis, said sleeve surrounding and removably mounted with separation of said mandrel components within said sleeve to said mandrel and further comprising a cutting structure fixed on an outer surface thereof, said cutting structure having a cutting structure axis aligned with said mandrel axis, and said cutting structure adapted to enlarge a window in a wall of a tubular;
said mandrel, said sleeve and said cutting structure on the outer surface of said sleeve all rotate in tandem.

2. The tool of claim 1 , wherein:
said mandrel retains said sleeve from shifting axially.

3. The tool of claim 1 , wherein:
said mandrel retains said sleeve from relatively rotating with respect to said mandrel.

4. The tool of claim 1 , wherein:
said mandrel is secured to each other with a thread.

5. The tool of claim 4 , wherein:
said sleeve comprising an extending member retained on said mandrel.

6. The tool of claim 5 , wherein:
said extending member engaging a recess on one part of said mandrel for rotational locking as another part of said mandrel is rotated to make up said thread.

7. The tool of claim 5 , wherein:
said components squeeze said extending member in opposed axial directions for fixation of said sleeve.

8. The tool of claim 5 , wherein:
said extending member is retained under said sleeve and adjacent said thread that holds components of said mandrel to each other.

9. The tool of claim 5 , wherein:
said extending member comprises a continuous or segmented ring or spaced lugs extending from an inner surface of said sleeve.

10. The tool of claim 1 , wherein:
said mandrel, sleeve and cutting structure flexibly bend without relative rotation when cutting through the tubular to make the window.

11. The tool of claim 1 , wherein:
said mandrel has a thread with an adjacent shoulder at an end thereof.

12. A milling tool for subterranean use, comprising:
a mandrel having a mandrel axis and at least one component;
a sleeve having a sleeve axis coinciding with said mandrel axis, said sleeve surrounding and removably mounted to said mandrel and further comprising a cutting structure fixed on an outer surface thereof, said cutting structure having a cutting structure axis aligned with said mandrel axis, and said cutting structure adapted to enlarge a window in a wall of a tubular;
said mandrel, said sleeve and said cutting structure on the outer surface of said sleeve all rotate in tandem;
said mandrel are secured to said sleeve with threads.

13. The tool of claim 12 , wherein:
said sleeve comprising an extending member retained on said mandrel.

14. The tool of claim 13 , wherein:
said mandrel comprising components that squeeze said extending member in opposed axial directions for fixation of said sleeve.

15. The tool of claim 13 , wherein:
said extending member is retained between spaced threads on said sleeve.

16. The tool of claim 13 , wherein:
said extending member comprises a continuous or segmented ring or spaced lugs extending from an inner surface of said sleeve.

17. A milling tool for subterranean use, comprising:
a mandrel having a mandrel axis and at least one component;
a sleeve having a sleeve axis coinciding with said mandrel axis, said sleeve surrounding and removably mounted to said mandrel and further comprising a cutting structure fixed on an outer surface thereof, said cutting structure having a cutting structure axis aligned with said mandrel axis, and said cutting structure adapted to enlarge a window in a wall of a tubular;
said mandrel, said sleeve and said cutting structure on the outer surface of said sleeve all rotate in tandem;
said mandrel is more flexible to bend under said sleeve than on either side of said sleeve.

18. The tool of claim 17 , wherein:
said mandrel has a passage therethrough with a larger dimension for said passage under said sleeve for flexibility under said sleeve than the dimension of said passage at other portions of said mandrel away from said sleeve.

19. A method of milling a tubular wall at a subterranean location, comprising:
providing a mandrel comprising multiple selectively separable components and a mandrel axis;
removably mounting a sleeve surrounding said mandrel, said sleeve further comprising a cutting structure fixed on an outer surface thereof, wherein said sleeve is removable by separation of said selectively separable components from within said sleeve;
aligning a cutting structure axis with said mandrel axis, said cutting structure adapted to enlarge a window in a wall of a tubular;
connecting said mandrel, said sleeve and said cutting structure on the outer surface of said sleeve to rotate in tandem;
cutting with said cutting structure.

Assignees

• Baker Hughes Inc
• Baker Hughes A Ge Co Llc

Inventors

• Hern Gregory L
• Hern Christopher R

Classifications

• E21B17/042

  Threaded · CPC title

• E21B29/06 Primary

  Cutting windows, e.g. directional window cutters for whipstock operations ({E21B29/005 and} E21B29/08 take precedence) · CPC title