Sealing apparatus and method

Abstract

An improved sealing apparatus ( 10, 110 ) for use in establishing a seal in an annulus ( 12,112 ) between a mandrel ( 18,118 ) and a bore wall ( 14,114 ) has an annular seal element ( 20,120 ) initially activateable between a first, retracted, configuration and a second, expanded, configuration. The seal element ( 20, 120 ) is disposed around a mandrel ( 18,118 ) and is free to move relative the mandrel ( 18,118 ) such that when the seal element ( 20,120 ) defines the second, expanded, configuration, pressurised fluid from the annulus ( 12;112 ) urges the seal element ( 20,120 ) radially outwards into sealing or enhanced sealing engagement with the bore wall ( 14,114 ).

1 . A sealing apparatus for use in establishing a seal in an annulus between a mandrel and a bore wall, the apparatus comprising:
 a mandrel; and   a seal element disposed on the mandrel, the seal element configured to define a first configuration and a second, expanded, configuration,   the apparatus configured so that fluid from the annulus acts on the seal element to urge at least part of the seal element radially outwards into sealing or enhanced sealing engagement with the bore wall.   
     
     
         2 . The apparatus of  claim 1 , wherein the first configuration comprises a retracted configuration. 
     
     
         3 . The apparatus of  claim 1 , wherein at least one of:
 the seal element comprises an annular seal element;   the seal element is disposed around the mandrel;   the apparatus comprises a plurality of the seal elements extending around the mandrel   
     
     
         4 . The apparatus of  claim 1 , wherein at least one of:
 the seal element is configured to expand in the presence of a selected activation medium;   the activation medium comprises a fluid;   the activation medium comprises fluid from the annulus between the apparatus and the bore wall.   
     
     
         5 . The apparatus of  claim 6 , wherein at least one of:
 the seal element comprises a material which swells in response to oil;   the seal element comprises a material which swells in response to oil, wherein   the seal element comprises an oil-swellable material, such as an oil-swellable elastomer;   the seal element comprises a material which swells in response to water   the seal element comprises a material which swells in response to water, wherein the seal element comprises a water swellable elastomer.   
     
     
         6 . The apparatus of  claim 1 , wherein at least one of:
 the apparatus is configured so that the seal element is moveable relative to the mandrel;   the seal element is in sealing engagement with the mandrel.   
     
     
         7 . The apparatus of  claim 1 , wherein at least one of:
 the apparatus is configured so that, in the second configuration, the annulus fluid is directed between the seal element and the mandrel;   the apparatus is configured so that, in the second configuration, the annulus fluid is directed between the seal element and the mandrel and the annulus fluid impinges on an inner circumferential surface of the seal element.   
     
     
         8 . The apparatus of  claim 1 , wherein at least one of:
 the apparatus is configured to define a fluid-receiving chamber between the seal element and the mandrel;   the fluid-receiving chamber is present when the seal element is in the first configuration;   the fluid-receiving chamber is formed when the seal element expands or moves from the first configuration to the second configuration.   
     
     
         9 . The apparatus of  claim 1 , wherein at least one of:
 the apparatus comprises a fluid passage configured to permit the passage of the pressurised fluid between the seal element and the mandrel;   the fluid passage comprises an axially-extending fluid passage;   the apparatus comprises a plurality of the fluid passages;   the fluid passage is of hemi-cylindrical form;   the apparatus comprises a plurality of the fluid passages and the fluid passages are of hemi-cylindrical form;   the apparatus comprises a plurality of the fluid passages arranged circumferentially.   
     
     
         10 . The apparatus of  claim 1 , wherein at least one of:
 the apparatus is configured so that the seal element engages the bore wall in the second configuration;   the apparatus is configured so that the seal element provides initial sealing engagement with the bore wall in the second configuration.   
     
     
         11 . The apparatus of  claim 1 , wherein at least one of:
 the apparatus defines a third configuration;   the apparatus is configured so that the seal element is urged into sealing engagement with the bore wall in the third configuration;   the seal element is configured to retain the third configuration.   
     
     
         12 . The apparatus of  claim 1 , wherein at least one of:
 the apparatus comprises at least one further seal member;   the further seal member is configured to define a cup seal;   the or each further seal member comprises at least one of: an elastomeric seal member; a compression seal member; a packing member; an expandable member; a swellable member; an oil-swellable member; a water-swellable member; an inflatable member, or any suitable style of seal member.   
     
     
         13 . The apparatus of  claim 12 , wherein at least one of:
 the apparatus comprises a single further seal member;   the apparatus comprises a plurality of further seal members.   the further seal members are of the same construction;   the further seal members are of different construction;   the further seal members are of different construction;   the further seal members are selected and/or arranged in order to provide selected properties to the apparatus   one or more further seal member comprises a material of greater hardness than one or more other seal member;   the apparatus is configured so that the seal element activates the further seal member;   the apparatus is configured so that the further seal member is at least partially activated by expansion of the seal element from the first configuration to the second configuration;   the apparatus is configured so that the further seal member is at least partially activated when the seal element is urged from the second configuration to the third configuration.   
     
     
         14 . The apparatus of  claim 1 , wherein at least one of:
 the apparatus comprises one or more end ring;   the apparatus comprises two end rings disposed at opposing ends of the apparatus;   the fluid passage is formed in one of the end rings;   at least one end ring comprises a radially-extending bore for receiving a retainer;   each end ring comprises a plurality of radially-extending bores, each for receiving a retainer   
     
     
         15 . The apparatus of  claim 1 , wherein at least one of:
 the apparatus is configured so that part of the annulus fluid acts towards retaining the seal element on the mandrel;   the apparatus is configured so that part of the annulus fluid acts towards retaining one or more further seal member on the mandrel.   
     
     
         16 . The apparatus of  claim 1 , wherein at least one of:
 the apparatus comprises a back-up assembly for supporting the seal element in maintaining sealing engagement with the bore wall.   
     
     
         17 . The apparatus of  claim 1 , wherein at least one of:
 the apparatus comprises a downhole packer;   the apparatus comprises a uni-directional downhole packer;   the apparatus comprises a cup seal packer.   
     
     
         18 . The apparatus of  claim 1 , wherein the apparatus is configured so the fluid from the annulus acts on the seal element when the seal element is in the second configuration. 
     
     
         19 . The apparatus of  claim 1 , wherein the seal element comprises a recess, groove or flute. 
     
     
         20 . A method comprising:
 providing an apparatus comprising a mandrel and a seal element for establishing a seal in an annulus between the mandrel and a wall of a bore;   disposing the apparatus in the bore,   activating the seal element from a first configuration to a second, expanded, configuration; and   urging at least part of the seal element radially outwards into sealing engagement or enhanced sealing engagement with the wall of the bore using fluid from the annulus between the mandrel and the wall of the bore.   
     
     
         21 . The method of  claim 20 , wherein the seal element may be initially activated from the first configuration to the second configuration prior to being urged into sealing engagement or enhanced sealing engagement with the wall of the bore.