Removable fracturing plug of particulate material housed in a sheath set by expansion of a passage through the sheath
The removable plug features a solid material that is housed in a porous container that has its shape changed to transition from the run in shape to the set shape. A swage is moved through a passage in the container to enlarge the passage and move the container to a borehole wall. The passage is then closed such as with a flapper valve or by moving in a mandrel into the expanded passage and lodging the mandrel in the expanded passage. Various release techniques are described.
1. A plug for subterranean use between zones where flow between said zones is to be minimized, comprising:
a porous sheath having a toroidal shape said sheath defining a volume containing a fill material therein and said toroidal shape further defining an interior void that forms a passage through said toroidal shape, said passage having a first and second end and a longitudinal axis extending through said ends, said passage isolated from fill material contained in said toroidal shape;
said sheath having a run in configuration when said first and second ends are spaced apart from each other with said passage open to flow and a set position when a swage is moved through said passage increasing and then retaining the passage dimension in a direction perpendicular to said axis by virtue of compaction of said fill material while pushing fluid through said sheath.
2. The plug of claim 1 , wherein:
said sheath is compressed as a result of passing of said swage through said passage.
3. The plug of claim 2 , wherein:
said passage is closed after said swage passes through said passage.
4. The plug of claim 3 , wherein:
said passage is closed with a valve mounted to said sheath or with an object contacting a seat located on a mandrel in said passage.
5. The plug of claim 4 , wherein:
said valve comprises a flapper.
6. The plug of claim 5 , wherein:
said flapper is biased to a closed position.
7. The plug of claim 6 , wherein:
the force of said bias is released upon the movement of said swage out of said passage.
8. The plug of claim 1 , wherein:
said sheath is placed in tension as said swage expands said passage.
9. The plug of claim 8 , wherein:
said swage is released or retrieved through said passage after said passage has been expanded.
10. The plug of claim 9 , wherein:
said passage is closed after said swage passes through said passage.
11. The plug of claim 10 , wherein:
said passage is closed with a valve mounted to said sheath or with an object contacting a seat located on a mandrel in said passage.
12. The plug of claim 11 , wherein:
said valve comprises a flapper.
13. The plug of claim 12 , wherein:
said flapper is biased to a closed position.
14. The plug of claim 13 , wherein:
the force of said bias is released upon the movement of said swage out of said passage.
15. The plug of claim 1 , wherein:
said sheath comprises a mesh.
16. The plug of claim 1 , wherein:
said sheath degrades with exposure to subterranean conditions or to changed conditions at the subterranean location from a remote location.
17. The plug of claim 16 , wherein:
said swage further comprises a releasably attached mandrel that is deposited in said passage as said swage moves through said passage;
said mandrel degrades with exposure to subterranean conditions or to changed conditions at the subterranean location from a remote location, which results in failure of said sheath and release of said fill material.
18. The plug of claim 17 , wherein:
said mandrel is made from a controlled electrolytic material.
19. The plug of claim 1 , wherein:
said sheath is made of Kevlar, nylon, a controlled electrolytic material or a woven textile material.
20. The plug of claim 1 , wherein:
said material comprises at least one of sand, controlled electrolytic material, rubber chips or coated proppant.
21. A wellbore treatment method using the plug of claim 1 , wherein said treatment method involves fluid delivery under pressure to a formation.