Patent Publication Number: US-10309196-B2

Title: Repeatedly pressure operated ported sub with multiple ball catcher

Description:
FIELD OF THE INVENTION 
     The field of the invention is ported subs capable of multiple cycles in conjunction with downhole ball catchers and more particularly where different sized balls can be diverted to an annular catch volume around a through passage with a diverter in one position and the through passage can be unobstructed with the diverter in a second position. 
     BACKGROUND OF THE INVENTION 
     Ball catchers are known in the art as described in U.S. Pat. No. 7,735,548 and US 2010/0236782. Their purpose is to stop balls blown through ball seats above from going further downhole and preventing operation of equipment further downhole, flow, or the ability to introduce other tools further downhole. One way to accomplish at least some of these objectives is to be able to store the captured balls in a volume outside the main passage. One device that captures a single ball outside a main passage is shown in U.S. Pat. No. 6,920,930, where the ball seat has a swing-away feature with the landed ball that, when swung, gets out of the main passage. A sleeve is then pushed down to trap the ball and the seat in a surrounding annular space while leaving the main passage open. The limitation of this device is that it can handle only one ball so if there are multiple balls involved, then multiple ball catchers each having a seat to accept a different sized ball is needed. In fracturing applications, there can be as many as dozens of balls blown through seats that need to be captured, making this device impractical for space and cost reasons. 
     More recently, another idea is described in U.S. Pat. No. 8,118,101 which can handle multiple balls of different sizes but uses an axially movable biased sleeve with a restriction in the main passage. Smaller balls than the restriction will just go through. The through passage is at all times restricted limiting further downhole operation or the delivery of tools to locations below the catcher. 
     The present invention presents a ball catcher actuated with displacement of a biased sleeve to force a diverter to the diverting position. As applied pressure is relieved by blowing a seated ball through a seat, other balls landed above the seated ball also make the trip through the seat and are diverted into an annular catch volume by a diverter held in a diverting position by continuing flow through the sleeve. As the flow through the sleeve is reduced or removed, a torsion spring returns the diverter to the open main passage position. These and other aspects of the present invention will be more readily apparent from a review of the detailed description of the preferred embodiment and the associated drawings while recognizing that the full scope of the invention is to be determined by the appended claims. 
     SUMMARY OF THE INVENTION 
     A ball seat is integrated with a movable biased sleeve. Movement of the sleeve against its bias moves a diverter from a position outside the through passage to a position across the main passage such that any balls that drop down will be directed by the diverter into an annular retention volume. In treatment of the formation for fluid loss, the movement of a seat with the seated ball opens lateral ports for delivery of sealing material. The shifting of the seat also move the diverter into the main through passage. Smaller balls are then introduced to close lateral ports above the seated ball so pressure can be built extrude the first ball. Once the seated ball blows through, the smaller balls come through the seat and are all diverted to an annular capture volume. The device is resettable for multiple operations. The cessation or reduction of fluid flow reopens the main through passage as the diverter is retracted. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a section view of the tool in a run in position; 
         FIG. 2  is the view of  FIG. 1  with a seated ball and pressure applied to open lateral ports; 
         FIG. 3  is the view of  FIG. 2  with treatment through the lateral ports completed and small balls delivered to close the lateral ports; 
         FIG. 4  is the view of  FIG. 3  where the seated ball is blown through the seat and it and the small balls are captured in an annular capture volume; 
         FIG. 5  is the view of  FIG. 4  where flow is removed allowing a spring to move the seat up to close the lateral ports and retract the diverter from the main passage; 
         FIG. 6  shows resumption of flow through the main passage with the diverter retraced from the main passage; 
         FIG. 7  is another view of the diverter in the  FIG. 1  position; 
         FIG. 8  is an end view of the diverter through the passage in the ball catcher when the diverter is in the  FIG. 4  position. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIG. 1 , the ball catcher B has an upper housing  12  connected to a lower housing  14 . A drill string that is not shown is connected above to connection  16  and below to connection  18 . A through passage  20  extends through housing components  12  and  14 . Arrow  22  shows flow through the ball catcher B in the run in position. A piston  24  has spaced seals  26  and  28  that straddle lateral ports  30  allowing piston  24  to act as a valve member for ports  30 . A spring  32  pushes off a shoulder  34  in upper housing  12  to put an uphole force on surface  36  of piston  24 . A ball seat  38  is supported by piston  24  such that without a seated ball  40  on seat  38  the through passage  20  is open between connections  18  and  16 . Connected to piston  24  is an extension tube  42  that ends at a lower end  44 . Continuing below the lower end  44  is an extending segment  46  that is disposed radially outside of a diverter or flapper  48  that pivots above a pin  50  that has a torsion spring  52  about pin  50  that biases the diverter or flapper  48  toward the  FIG. 1  position where the diverter or flapper  48  is retracted out of the passage  20 . Pin  50  is connected to extension tube  54  that is a part of the upper housing  12 . In the  FIG. 1  position a lateral opening  56  is closed by a flapper  48  but flow through or around the diverter or flapper  48  is possible into annular capture volume  58  defined between extension tube  54  and lower housing  14 . Note that the volume  58  is not sealed so that flow that is diverted through opening  56  as indicated by arrow  60  in  FIG. 4  rejoins flow through passage  20  as indicated by arrow  22 . 
     Referring back to  FIG. 2 , when fluid losses to the formation are detected and there is a need to stop such loss such as during drilling, the ball  40  is landed on seat  38  and pressure is built up on seated ball  40  to move piston  24  against stop  62  so that ports  30  open for flow as indicated by arrows  64 . When the sealant pumping to stop the fluid loss to the formation is concluded, another ball  66  is delivered into the catcher B for each lateral opening  30 . Although two are shown, the amount of the openings  30  can be less or more. Once a ball  66  is in each opening  30 , built up pressure blows ball  40  through seat  38  which sends ball  40  against the now displaced diverter  48  that is in the passage  20  so that passage  56  is open and ball  40  is captured in volume  58 . Looking at  FIG. 4 , when the ball  40  blows through seat  38 , it allows spring  32  to push piston  24  back to the  FIG. 1  position. It also allows the two illustrated balls  66  to release from being up against ports  30  such that balls  66  fall against the diverter  48  and through opening  56  and into capture volume  58 . The movement of piston  24  under force from spring  32  also moves extending segment  46  from the  FIG. 3  position where it forced the diverter  48  to rotate into passage  20  and stay in that position by overcoming the force of torsion spring  52 . On pressure release from blowing ball  40  through seat  38 , the movement of piston  24  and connected extension tube  42  can experience enough of a viscous drag force due to forcing fluid into the spring chamber through a restriction with the upper housing  12  to ensure that the diverter  48  remains in the  FIG. 4  position long enough for the fluid to reach and hold the diverter  48  down into the passage  20 . Alternatively, the movement of the piston  24  and associated tube under the force of spring  32  can also involve pushing oil through an orifice (not shown) as a way to regulate the speed of the movement of piston  24  over a long enough period of time to let the diverter  48  to remain in passage  20  until all balls  66  are diverted.  FIG. 5  shows the piston  24  again blocking ports  30  so that pumping straight through passage  20  can resume as the diverter  48 , now no longer biased by the extending segment  46  that has moved up with the piston  24  or by impinging fluid flow, is returned to a retracted position out of passage  20  due to the action of torsion spring  52 . In  FIG. 6 , as in  FIG. 1 , arrow  22  indicates the straight through flow through passage  20  can resume. The above process can be repeated many times with the limitation being the capacity of volume  58  to store balls without a trip out of the hole to remove the captured balls. Balls  66  can be smaller than ball  40  making the device capable of catching multiple balls of different sizes in a device that does not restrict the drift dimension of the through passage  20 . 
       FIGS. 7 and 8  show different views of the diverter  48 . In  FIG. 7  the  FIG. 1  position is illustrated from a different perspective.  FIG. 8  shows diverter  48  from an end view along passage  20  when the diverter  48  is in the  FIG. 4  position. There can be openings  70  in the diverter and side gaps  72  to allow the diverter  48  to swing through an arc. The minimum ball size to be diverted is larger than openings  70  or gaps  72 . 
     Those skilled in the art will appreciate that what is described is a ported sub with a selectively opened lateral port that is activated by tubing pressure in a drill string while the bit is selectively isolated so that sealer material can be pumped one or more times into a formation just drilled that is taking fluids. After sealant delivery the path to the bit can be reopened and the lateral ports closed so that drilling can resume. Reopening the path to the drill bit occurs from blowing a ball through a seat on a piston that selectively opens the lateral ports. The pressure is built on the seated ball by using smaller balls to seal off the lateral ports so that built up pressure on the seated ball is forced through the piston that selectively opens the lateral ports. A diverter directs the ball blown through the seat to an annular capture volume. The smaller balls can drop through the larger ball seat to be similarly diverted to the annular capture volume. Reducing flow rate allows a return spring to move the piston back to the run in position for more drilling with straight through pumping to the nozzles on the drill bit. 
     Although a drilling application is described, other applications are contemplated. The balls for the lateral ports can be the same size or a different size than the ball that lands on the seat of the piston. The lateral ports can be reopened one or more times by repeating the process with the limit being the size of the capture volume to hold all the balls outside the main passage. 
     The above description is illustrative of the preferred embodiment and many modifications may be made by those skilled in the art without departing from the invention whose scope is to be determined from the literal and equivalent scope of the claims below: