Hydraulic fracturing process and corresponding equipment

Abstract

The present invention relates especially to a hydraulic fracturing equipment of the rock of a well (A), characterised in that it comprises, on the one hand: a conduit ( 1 ) provided along its external face with at least one pair of expandable metallic tubular sleeves ( 2 ) fixedly, connected to the conduit ( 1 ), this conduit having opposite each sleeve ( 2 ) at least one opening ( 10 ) known as “first opening” to put the internal space of the conduit ( 1 ) in communication with the space delimited by the latter and each sleeve ( 2 ), and opposite the space separating the two sleeves ( 2 ) of a same pair at least one other opening ( 3 ), known as “second opening” for putting the internal space of the conduit ( 1 ) in communication with the interior of the well (A); a tubular element ( 4 ) of diameter provided to allow it to be engaged in said conduit ( 1 ), such that there is a free annular space between them; the wall of this tubular element ( 4 ) comprising at least one first through-hole ( 42 ); the wall being also provided externally with at least two deformable rings ( 6 ) located on either side of said first orifice ( 42 ), capable of being applied hermetically against the internal face of said conduit ( 1 ).

1 . Hydraulic fracturing equipment of the rock of a well, wherein it comprises, on the one hand:
 a conduit provided along its external face with at least one pair of expandable metallic tubular sleeves fixedly, connected to the conduit, this conduit having opposite each sleeve at least one opening known as “first opening” to put the internal space of the conduit in communication with the space delimited by the latter and each sleeve, and opposite the space separating the two sleeves of a same pair at least one other opening, known as “second opening” for putting the internal space of the conduit in communication with the interior of the well;   a tubular element of diameter provided to allow it to be engaged in said conduit, such that there is a free annular space between them;   the wall of this tubular element (4) comprising at least one first through-hole (42);   the wall being also provided externally with at least two deformable rings located on either side of said first orifice, capable of being applied hermetically against the internal face of said conduit ( 1 ).   
     
     
         2 . The equipment as claimed in  claim 1  wherein the distance between the deformable rings is greater than the distance separating said first openings of said conduit. 
     
     
         3 . The equipment as claimed in  claim 1 , wherein it comprises at least two first through-holes which are arranged in the longitudinal direction of the element according to two zones whereof the mutual distance is substantially equal to that of the first openings of said conduit. 
     
     
         4 . The equipment as claimed in  claim 1 , wherein the means which prevent said fluid which is funnelled into said second opening from terminating in the space separating the two sleeves consist of a sleeve with sealed ends, fixed on the external wall of said conduit, sleeve which is capable of breaking under predetermined pressure known as “breaking pressure”. 
     
     
         5 . The equipment as claimed in  claim 1 , wherein said tubular element comprises at least one second orifice and two pairs of rings, the second orifice being located between the rings opposite the two pairs of rings. 
     
     
         6 . The equipment as claimed in  claim 5 , wherein two rings are arranged on either side of said first orifices. 
     
     
         7 . The equipment as claimed in  claim 6 , wherein the rings of a same pair are separated longitudinally by a distance greater than that which separates the first and the second openings of said conduit 
     
     
         8 . The equipment as claimed in  claim 1 , wherein said tubular element comprises means capable of blocking its downstream end on request. 
     
     
         9 . The equipment as claimed in claim,  8 , wherein said means comprise a valve. 
     
     
         10 . The equipment as claimed in  claim 1 , wherein said conduit and said tubular element have mutual immobilisation means. 
     
     
         11 . The equipment as claimed in  claim 8  said valve is coupled with said mutual immobilisation means such that said valve blocks said end only when said immobilisation means cooperate. 
     
     
         12 . The equipment as claimed in  claim 1 , wherein said second orifice is provided with a closing member directed axially, which moves from a closing position to an opening position under the effect of a rise in pressure without opposing the longitudinal passage of fluid. 
     
     
         13 . The equipment as claimed in  claim 12 , wherein said member comprises a hollow piston retracted into a closing position by elastically deformable means such as a spring. 
     
     
         14 . The equipment as claimed in  claim 1 , wherein said conduit and said tubular element have mutual immobilisation means in two distinct positions offset longitudinally. 
     
     
         15 . The equipment as claimed in  claim 10 , wherein said means are arranged so as to allow passage from one to the other of the distinct positions by sliding of said tubular element relative to said conduit ( 1 ).