Lock ring hold open device for frac sleeve
View Patent ↗A lock ring fits into a housing recess defined by a sliding member such as a sleeve. The lock ring is loosely fitted in the recess when the sleeve is in an initial position. The lock ring is preferably smooth on an outer dimension and has a beveled end. The beveled end engages an internal taper in the housing if a force is placed on the sliding sleeve to return it toward the original position. Preferably the shifting of the sleeve to a ports open position places the ratchet on the sleeve in alignment with the lock ring to hold the sliding sleeve locked in the open position.
1. An assembly for locking return relative movement between components of a borehole tool after allowing an initial relative movement between components, comprising:
a housing:
a member movably mounted to said housing defining a recess in between, said member comprising a part of a selectively meshing ratchet pattern;
said member comprises a sliding sleeve selectively covering at least one port in a wall of said housing; and
a lock ring loosely mounted in said recess and having a cooperatively meshing lock ring ratchet pattern, said lock ring wedging against said housing and said member on an attempt of said return relative movement, said lock ring having a smooth exterior surface opposite said ratchet pattern on an interior surface thereof.
2. The assembly of claim 1 , wherein:
said lock ring comprises an end bevel.
3. The assembly of claim 2 , wherein:
said end bevel selectively contacting a mating bevel on said housing.
4. The assembly of claim 1 , wherein:
said lock ring is guided by said housing to maintain a parallel orientation to said member while loosely mounted in said recess.
5. The assembly of claim 1 , wherein:
said sliding sleeve further comprises a structure in a passage therethrough adapted to accept an object thereon for pressure buildup that translates said meshing ratchet pattern parts over each other.
6. The assembly of claim 5 , wherein:
said housing comprising a flowpath therethrough in alignment with said passage in said sliding sleeve.
7. The assembly of claim 1 , wherein:
said lock ring is continuous for 360 degrees.
8. A treatment method, comprising:
operating at a predetermined location in a borehole an assembly for locking return relative movement between components of a borehole tool after allowing an initial relative movement between said components to open access to a formation, comprising:
a housing comprising at least one port;
a member movably mounted to said housing defining a recess in between, said member comprising a part of a selectively meshing ratchet pattern;
providing a sliding sleeve as said member, said sliding sleeve selectively covering said at least one port in a wall of said housing;
a lock ring loosely mounted in said recess and having a cooperatively meshing lock ring ratchet pattern, said lock ring wedging against said housing and said member on an attempt of said return relative movement;
treating the formation through said at least one port; and
locking said member against closing said at least one port.
9. The method of claim 8 , comprising:
providing a smooth exterior surface on said lock ring opposite said ratchet pattern on an interior surface thereof.
10. The method of claim 8 , comprising:
providing an end bevel on said lock ring.
11. The method of claim 10 , comprising:
selectively contacting said end bevel to a mating bevel on said housing.
12. The method of claim 8 , comprising:
guiding said lock ring with said housing to maintain a parallel orientation to said member while said lock ring is loosely mounted in said recess.
13. The method of claim 8 , comprising:
providing a structure in a passage through said sliding sleeve adapted to accept an object thereon for pressure buildup that translates said meshing ratchet pattern parts over each other.
14. The method of claim 13 , comprising:
providing a flowpath through said housing in alignment with said passage in said sliding sleeve.