Isolation system with integrated slip and extrusion prevention mechanisms and methods of use
An example apparatus includes a rod, an uphole coupling through which the rod extends. An expansion ring is positioned on the rod below the uphole coupling, and an elastomer element is positioned on the rod below the expansion ring. A receptacle is positioned on the rod below the elastomer element and is configured to receive a portion of the elastomer element. A guardian ring is positioned on the rod below the receptacle, and a portion of the receptacle is received in the guardian ring. A cap is positioned on the rod and arranged for contact with the guardian ring, and a barrel to which the cap is connected. The rod is partially received in the barrel, and one of the barrel and the rod is movable with respect to the other of the barrel and the rod to exert a compression load on the elastomer element.
1 . An apparatus, comprising:
a rod;
an uphole coupling through which the rod extends;
an expansion ring positioned on the rod below the uphole coupling;
an elastomer element positioned on the rod below, and in contact with, the expansion ring;
a metal receptacle positioned on the rod below the elastomer element and configured to receive a portion of the elastomer element;
a guardian ring positioned on the rod below the receptacle, and a portion of the receptacle is received in the guardian ring;
a cap positioned on the rod and in contact with the guardian ring; and
a barrel to which the cap is connected, wherein the rod is partially received in the barrel, and one of the barrel and the rod is movable with respect to the other of the barrel and the rod to exert a compression load on the elastomer element.
2 . The apparatus as recited in claim 1 , wherein the guardian ring has a helical configuration that is configured to assume a compressed state, and a relaxed state.
3 . The apparatus as recited in claim 1 , wherein the elastomer element is configured to assume a compressed state in which the elastomer element is elastically deformed, and when the elastomer element is in the compressed state, an outside diameter of the elastomer element is greater than an outside diameter of the elastomer element when the elastomer element is in a relaxed state.
4 . The apparatus as recited in claim 1 , wherein when the apparatus is in a compressed state within a wellbore, the guardian ring and the elastomer element are in annular contact with an interior diameter of the wellbore.
5 . The apparatus as recited in claim 1 , wherein the guardian ring is configured to expand under compression and prevent extrusion of the elastomer element when the apparatus is positioned in a downhole location.
6 . The apparatus as recited in claim 1 , wherein the apparatus comprises a frac plug.
7 . The apparatus as recited in claim 1 , wherein when the guardian ring is positioned in a wellbore, and then compressed, the guardian ring prevents slippage of the apparatus along the wellbore.
8 . The apparatus as recited in claim 1 , wherein the guardian ring is positioned downhole of the elastomer element when the apparatus is in a downhole location, and the apparatus further comprises another guardian ring that is positioned uphole of the elastomer element when the apparatus is in the downhole location.
9 . The apparatus as recited in claim 1 , wherein the guardian ring prevents imposition of a differential pressure across the elastomer element when a frac process is being performed using the apparatus in a compressed state.
10 . The apparatus as recited in claim 1 , wherein the apparatus comprises an electrical conductor passing through the rod.
11 . The apparatus as recited in claim 1 , wherein the expansion ring is elastically deformable and is configured to change shape under compression.
12 . The apparatus as recited in claim 1 , wherein the receptacle comprises a retainer that limits axial travel of the guardian ring relative to the receptacle when the apparatus is compressed.
13 . A method, comprising:
deploying a frac plug to a downhole location in a wellbore; and
using the frac plug to seal a portion of the wellbore by performing operations comprising:
exerting pressure on a portion of the frac plug;
compressing, in response to exertion of the pressure, an elastomer element of the frac plug by, and between, an expansion ring of the frac plug and a metal receptacle of the frac plug,
wherein compression of the elastomer element by, and between, the expansion ring and the metal receptacle causes an outside diameter of the elastomer element to increase relative to a size of the outside diameter of the elastomer element prior to the compression; and
exerting, by the compressed elastomer element, a pressure on a casing disposed in the wellbore, until that pressure reaches a sealing pressure sufficient to seal the portion of the wellbore to prevent flow of fluids and/or solids past the frac plug.
14 . The method as recited in claim 13 , wherein a guardian ring, in contact with the metal receptacle, when compressed, exerts an axial load on the metal receptacle.
15 . The method as recited in claim 13 , wherein an expansion ring positioned between the elastomer element and an uphole coupling of the frac plug prevents extrusion of the elastomer element when the pressure is exerted on the frac plug.
16 . The method as recited in claim 13 , wherein a guardian ring, in contact with the metal receptacle, prevents extrusion of the elastomer element past the guardian ring when the pressure is exerted on the frac plug.
17 . The method as recited in claim 13 , wherein the pressure is exerted on the frac plug by introducing hydraulic fluid into a fluid passageway of a barrel configured and arranged to act on a guardian ring that contacts the metal receptacle.
18 . The method as recited in claim 13 , wherein the method is performed as part of a frac'ing process at one or more stages of the wellbore.
19 . The method as recited in claim 13 , wherein when a first guardian ring in contact with the metal receptacle, and another guardian ring, are both expanded in response to exertion of the pressure, the first guardian ring and the another guardian ring prevent imposition of a differential pressure across the elastomer element.
20 . The method as recited in claim 13 , wherein after the wellbore is sealed, the frac plug is reused to seal another portion of the wellbore.