# US 8,739,879 B2 · Hydrostatically powered fracturing sliding sleeve > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,739,879 B2 - Document ID: US8739879B2 - Status: Granted - Kind: B2 - Application number: 13/333,540 - Filed: 2011-12-21 - Published: 2013-06-27 - Granted: 2014-06-03 - Earliest claimed: 2011-12-21 - Assignees: Baker Hughes Incorporated - Applicants: James G. King - Inventors: James G. King - Web page: https://patentgrep.com/patent/US8739879B2 ## CPC - E21B 34/142: {unsupported or free-falling elements, e.g. balls, plugs, darts or pistons} - E21B 34/103: {with a shear pin} - E21B 43/26: by forming crevices or fractures - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract A series of sliding sleeves is actuated by a single ball that lands on a first ball seat and shifts the ball seat. The shifting of the ball seat also allows tubing pressure to communicate to a formerly atmospheric chamber on one side of a piston integrated into the back side of the sliding sleeve. The other side of the piston remains at atmospheric pressure so that the shifting of the ball seat not only releases the ball to go to the next ball seat but also puts a net force on the sliding sleeve to shift it against a travel stop to open a port to allow fracturing, even if there is cement in the annulus around the opened port. ## Claims ### Claim 1 A completion assembly for subterranean use, comprising: a tubular housing having a plurality of axially spaced ports each associated with a sliding sleeve valve such that said sliding sleeve valves are axially spaced from each other; said sliding sleeve valves further comprising a movable seat responsive to a fluid pressure to a predetermined value on an object that sequentially lands on said seats; individual movement of one of said movable seats redirects at least a portion of said fluid pressure to release a boost force to act on a respective said sliding sleeve valve associated with said moving movable seat, to shift said associated sliding sleeve valve and release the object to the adjacent said seat that has yet to shift. ### Claim 2 (depends on 1) The assembly of claim 1, wherein: said sliding sleeve valves defining a piston disposed in an annular space between said housing and said sliding sleeve valve that is subjected to a pressure imbalance to provide said boost force. ### Claim 3 (depends on 2) The assembly of claim 2, wherein: said pressure imbalance derives from access of tubing pressure in said housing to said piston. ### Claim 4 (depends on 3) The assembly of claim 3, wherein: said access of tubing pressure to said piston results from movement of said seat. ### Claim 5 (depends on 4) The assembly of claim 4, wherein: said access of tubing pressure to said piston results from movement of said sliding sleeve valve. ### Claim 6 A completion assembly for subterranean use, comprising: a tubular housing having a plurality of axially spaced ports each associated with a sliding sleeve valve such that said sliding sleeve valves are axially spaced from each other; said sliding sleeve valves further comprising a movable seat responsive to a fluid pressure to a predetermined value on an object that sequentially lands on said seats; individual movement of one of said movable seats redirects at least a portion of said fluid pressure to release a boost force to act on a respective said sliding sleeve valve associated with said moving movable seat, to shift said associated sliding sleeve valve and release the object to the adjacent said seat that has yet to shift; said sliding sleeve valves defining a piston disposed in an annular space between said housing and said sliding sleeve valve that is subjected to a pressure imbalance to provide said boost force; said pressure imbalance derives from access of tubing pressure in said housing to said piston; said access of tubing pressure to said piston results from movement of said seat; said piston defines opposed low pressure chambers; movement of a respective said sliding sleeve valve opens one of said chambers associated with said respective sliding sleeve valve to pressure in said tubing. ### Claim 7 (depends on 6) The assembly of claim 6, wherein: movement of a respective said sliding sleeve valve initiates a gap to pressure in said tubing due to relative movement between a seal and said respective sliding sleeve valve. ### Claim 8 (depends on 7) The assembly of claim 7 wherein: movement of a respective said sliding sleeve valve allows a respective said seat to move radially outward toward said housing to allow the object to pass. ### Claim 9 (depends on 8) The assembly of claim 8, wherein: movement of a respective said sliding sleeve aligns a port on said respective sliding sleeve with a port on said housing. ### Claim 10 (depends on 9) The assembly of claim 9, wherein: movement of a respective one of said seats breaks at least one first shear pin; movement of a respective one of said sliding sleeves breaks at least one second shear pin. ### Claim 11 (depends on 10) The assembly of claim 10, wherein: said first shear pin breaks before said second shear pin. ### Claim 12 (depends on 6) The assembly of claim 6, wherein: said chamber that is exposed to tubing pressure grows in volume while another chamber on the opposed side of said piston shrinks in volume. ### Claim 13 (depends on 12) The assembly of claim 12, wherein: pressure on said piston from exposure to tubing pressure is enhanced by raising the tubing pressure after said exposure. ### Claim 14 A completion assembly for subterranean use, comprising: a tubular housing having a plurality of axially spaced ports each associated with a sliding sleeve valve such that said sliding sleeve valves are axially spaced from each other; said sliding sleeve valves further comprising a movable seat responsive to a fluid pressure to a predetermined value on an object that sequentially lands on said seats; individual movement of one of said movable seats redirects at least a portion of said fluid pressure to release a boost force to act on a respective said sliding sleeve valve associated with said moving movable seat, to shift said associated sliding sleeve valve and release the object to the adjacent said seat that has yet to shift; said sliding sleeve valves defining a piston disposed in an annular space between said housing and said sliding sleeve valve that is subjected to a pressure imbalance to provide said boost force; said pressure imbalance derives from access of tubing pressure in said housing to said piston; said access of tubing pressure to said piston results from movement of said sliding sleeve valve; said piston defines opposed low pressure chambers; movement of a respective one of said sliding sleeve valve opens one of said chambers associated with said piston to pressure in said tubing. ### Claim 15 (depends on 14) The assembly of claim 14, wherein: movement of a respective said sliding sleeve valve initiates a gap to pressure in said tubing due to relative movement between a seal and said respective sliding sleeve valve. ### Claim 16 (depends on 15) The assembly of claim 15 wherein: movement of a respective said sliding sleeve valve allows a respective said seat to move radially outward toward said housing to allow the object to pass. ### Claim 17 (depends on 16) The assembly of claim 16, wherein: movement of a respective said sliding sleeve aligns a port on said respective sliding sleeve with a port on said housing. ### Claim 18 (depends on 17) The assembly of claim 17, wherein: movement of a respective one of said seats breaks at least one first shear pin; movement of a respective one of said sliding sleeves breaks at least one second shear pin. ### Claim 19 (depends on 18) The assembly of claim 18, wherein: said first shear pin breaks before said second shear pin. ### Claim 20 (depends on 14) The assembly of claim 14, wherein: said chamber that is exposed to tubing pressure grows in volume while another chamber on the opposed side of said piston shrinks in volume. ### Claim 21 (depends on 20) The assembly of claim 20, wherein: pressure on said piston from exposure to tubing pressure is enhanced by raising the tubing pressure after said exposure.