Abstract
A downhole apparatus for collecting solids fallback in the tubing of an oil producing borehole comprises two or more baskets to collect the solids fall back, each basket partially occupying a portion of the inner cross section of the tubing, leaving a portion of the inner cross section of the tubing having an unrestricted flow path. The baskets when considered in plan view along longitudinal axis of the tubing are distributed such that together they cover substantially the whole area of the tubing while leaving an unobstructed non-straight flowpath around the baskets.
Claims
1-16. (canceled)
17. A downhole apparatus for collecting solids fallback in a production tubular, comprising: a body; a first connection component disposed at a first end of the body; a second connection component disposed at a second end of the body; and a plurality of baskets disposed longitudinally in the body, wherein each of the plurality of baskets comprises a basket wall provided with openings to permit fluid flow therethrough.
18. The downhole apparatus of claim 17, wherein the basket surface of each of the plurality of baskets comprises a base, and open top and a side wall.
19. The downhole apparatus of claim 18, wherein the side wall is oriented parallel to a primary direction of fluid flow through the solid collection basket apparatus.
20. The downhole apparatus of claim 18, wherein the base is oriented at an angle from a longitudinal reference line following lengthwise along the solid collection basket apparatus.
21. The downhole apparatus of claim 17, wherein at least one of the one or more openings comprises a slot, aperture or mesh opening aligned with the longitudinal axis of the body.
22. The downhole apparatus of claim 18, wherein the base of each basket includes a filter or mesh screen configured to permit fluid flow while retaining solid particles.
23. The downhole apparatus of claim 17, wherein each basket include flow-responsive elements that open under upward flow and restrict reverse flow.
24. The downhole apparatus of claim 17, wherein the check valve is a flapper valve or V-shaped bar and rod assembly.
25. A method of collecting solids fallback in a downhole fluid, comprising: providing a solid collection basket having a longitudinal axis, wherein the solid collection basket allows a fluid to flow along the longitudinal axis in a first direction or separately in a second direction, wherein the second direction comprises a direction which is a reverse of the first direction; flowing a fluid including particulate matter through the solid collection basket at an initial rate of fluid flow, wherein the flowing comprises the fluid flowing through the solid collection basket in the first direction; directing the fluid at least partially through one or more baskets disposed along the longitudinal axis of the solid collection basket, wherein each of the one or more baskets comprises a basket surface comprising one or more openings; trapping at least a portion of the particulate matter in at least one of the one or more baskets when the rate of fluid flow slows or becomes suspended, or the flowing reverses such that the flowing comprises the fluid flowing in the second direction; and cleaning the one or more baskets as the rate of fluid flow is restored to the initial rate of flow or as the flowing returns to comprising the fluid flowing through the solid collection basket in the first direction.
26. The method of claim 25, wherein the flowing further comprises flowing the fluid in the first direction along an alternating, serpentine or circulating path past each of the one or more baskets.
27. The method of claim 26, wherein the flowing further comprises flowing the fluid smoothly upward through and between the one or more baskets.
28. A system for trapping particulate matter disposed in a fluid produced from a wellbore, comprising: production tubing disposed in a wellbore, the production tubing configured to flow a fluid produced from the wellbore; a solid collection basket apparatus connected to the production tubing, the solid collection basket apparatus comprising: a body, a first connection component disposed at a first end of the body, a second connection component disposed at a second end of the body, and a plurality of baskets disposed longitudinally in the body, wherein each of the plurality of baskets comprises a basket surface comprising one or more openings; a pump or lifting mechanism connected to the solid collection basket apparatus, the lifting device configured to flow the fluid at a rate of flow into the production tubing through the solid collection basket apparatus; wherein the solid collection basket apparatus collects particulate matter disposed in the fluid when the rate of flow slows, becomes suspended, or reverses.
29. The system of claim 28, wherein the lifting device comprises an electric submersible pump.
30. The system of claim 28, wherein the solid-collection basket apparatus is installed below a pump inlet in an inverted orientation such that the open ends of the baskets face downhole, thereby collecting solids falling back toward the pump before they enter the pump.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] There will now be described, by way of example only, embodiments of the invention with respect to the following drawings,
[0037] FIG. 1 is a section side view of tubing in a well with one embodiment of the complete apparatus installed inside it.
[0038] FIG. 2 is a section side view of one embodiment of the invention.
[0039] FIG. 3 is a section plan view of FIG. 2.
[0040] FIG. 4 is a section side view of another embodiment of the invention incorporating a flapper valve in the bottom of the basket of the tool.
[0041] FIG. 5 is a section plan view of FIG. 4 with the flapper valve shown closed (the flapper valve having filter flow through passages in its construction.
[0042] FIG. 6 is a section plan view of FIG. 4 with the flapper valve shown open.
[0043] FIG. 7 is a section side view of tubing in a well with another embodiment of the complete apparatus installed inside it deployed on slickline and suspended in the tubing using a commercially available hanger (22).
[0044] FIG. 8 is a section side view through a rod lift pump, with the apparatus installed inside the plunger body.
[0045] FIG. 9 is a section side view of a well bore production tubing with a rod lift string installed inside it.
[0046] FIG. 10a is a similar view to FIG. 9 with the rod lift joint centralised at both ends and solid fall-back baskets located on the rod lift shaft.
[0047] FIGS. 10b, 10c, 10d and 10e show cross sections of the embodiment of FIG. 10a through the lines A-A, B-B, C-C, D-D of FIG. 10a respectively.
[0048] FIG. 11 is a plan view of another embodiment of the invention.
[0049] FIG. 12 is a side view E of FIG. 11.
[0050] FIG. 13 is a side view G of FIG. 12.
[0051] FIG. 14 is a plan view F of FIG. 13.
[0052] FIG. 15 is a table showing details of typical configurations, dimensions, solid fall-back storage volumes etc.
[0053] FIG. 16 is a section side view through another embodiment of the invention.
[0054] FIG. 17 is detail A of FIG. 16.
[0055] FIG. 18 is end section view OD of FIG. 17.
[0056] FIG. 19 is end section view EE of FIG. 17.
[0057] FIG. 20 is a similar view to FIG. 17 with sand fallback being collected in the side basket.
[0058] FIG. 21 is a side view of FIG. 17.
[0059] FIG. 22 is an isometric view of the two shelfs shown in FIG. 17.
[0060] FIG. 23 is a section side view through another embodiment of the invention.
[0061] FIG. 24 is an orthogonal side view of FIG. 22.
[0062] FIG. 25 is an end view of FIG. 24.
[0063] FIG. 26 is a similar view to FIG. 25 in a folded position.
[0064] FIG. 27 is a section side view of two of the components shown in FIG. 23, each orientated 180 degrees with each other.
[0065] FIG. 28 is a rendered view similar to FIG. 27, with the addition of a centraliser.
[0066] FIG. 29 is a blown-up view of detail G.
[0067] FIG. 30 is a section side view through a shelf with another embodiment of the filter.
[0068] FIG. 31 is a similar view to FIG. 30 with flow in the reverse direction.
[0069] FIG. 32 is a plan view of a continuous V wire screen.
[0070] FIG. 33 is a section side view of the continuous V wire screen shown in FIG. 32.
[0071] FIG. 34 is a side view of the continuous V wire screen shown in FIG. 32.
[0072] FIG. 35 is a section side view of the shelf with the screen shown in FIG. 32 inserted into the horizontal slot.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0073] Referring to FIGS. 1 to 6, there is shown production tubing, a check valve 2 and a knock off circulation port 3 Inside the joint of tubing, is mounted modules 4 which consist an upper ring 5 a lower ring 6 an internal bore 7 in lower ring in which the reduced diameter 8 of the upper rig fits, this enables these modules to be stacked together. A basket compartment with an open top 9 into which solids can fall into the basket, and sides of straight cord 10 and circumference 11 and the base 12. The mesh size of the basket is selected to trap the solids in the produced fluid, and could 50 mesh to 100 mesh or any other preferred mesh size. The lower surface of the basket could also incorporate a flapper type valve 13 with ports 14 and a mesh 15 in the port, in normal operation the flapper will be flat to the bottom of the basket, but, in the event of a surge of solid slurry, it would be advantageous for the flapper to open and provide virtually full bore flow area 16 for the slurry to flow through. The normal flow path 17 is always open. To protect the basket from erosion, a deflector 18 could be fitted which would direct flow to the flow passage 17, and protect the lower surface of the basket 19, it would have slots in it so allowing the passage of fluid during solids fallback. Ideally, the modules are stacked on top of each other, and when solids fall back, initially the upper basket 20 fits, any solids that by pass it fill the next basket down 21, and this is repeated to basket 22, 23, 24, 25 etc.
[0074] Referring to FIG. 7, the system could also be deployed riglessly, the modules described above could be connected together and conveyed into a well using slickline and suspended in the well using a commercially available tool 22. This is available from a company called D&D International, it is called a AD-2 tubing stop and can be used in any tubing string. The AD-2 tubing stop can be set any place in the tubing string with a nominal tubing ID. It can also be used as a slick line-retrievable anchor. The AD-2 tubing stop is held in the set position by slips that engage the tubing wall. When installing the AD-2 tubing stop, the appropriate GS pulling tool and the attached stop are lowered into the tubing string using standard slick line methods. The AD-2 tubing stop can be set by simple manipulation of the wireline which shears the pin and the spring forces the slips onto the cone locking the tubing stop in place. The tubing stop body, which contains the slip cone, is driven tightly behind the slips by heavy downward jarring. When removing the AD-2 tubing stop, upward jarring with the appropriate GS pulling tool causes the slips to release and allows the tubing stop to be pulled to the surface.
[0075] It is attached to the upper most module 30 top of assembly via an adaptor 31 which has a threaded box connection 23 on its lower end and a threaded connection 32 on its upper end which attaches it to the AD-2 assembly 22. Passages 33 in the adaptor allow the flow from the module passages 34 into the internal bore 35 of the AD-2 tool and into the production tubing 36 above the AD-2.
[0076] Referring to FIG. 8 there is shown a section side view of a rod lift type pump. The rod 40 from surface attaches to the top of the plunger 41, at the top of the plunger is a series of funnels described in an earlier patent application. The plunger sits inside a static pump barrel, at the lower end of the pump barrel is a static non return valve 43. At the bottom of the plunger piston is a travelling non return valve 44. The modules 4 described earlier could reside inside the plunger piston and could collect the fall-back solids and prevent them from falling onto the travelling non-return valve 44.
[0077] Referring to FIGS. 9 and 10, there is shown a section through the production tubing 50 somewhere between the pump and surface. Inside the production tubing is a rod lift string 51, and this is reciprocated up and down to operate the downhole pump. If ceramic or other material centralisers 52 are placed at the top and bottom of a rod, then for that section of production tubing the rod will be perfectly centralised. Attached to the rod would be simple baskets 53 which would only occupy one side of the tubing/rod annulus 54 while the other side 55 would be clear for production fluid to freely flow. The baskets would be placed on alternate sides 56,57 so as to capture all the solids fall back in the event of a pump shutdown.
[0078] Referring to FIGS. 11 to 14 there is shown another embodiment of the invention. It consists of two side frame members 60,61. The side frames act as a structural member to which everything else is attached. To make a basket, a straight mesh screen 62 encloses the central line, the inner surface of the tubing 63, is the outer surface of the basket, and a flat half circle plate 64 which has a close fit to the tubing 63 and attaches to the frames 60,61 provides the bottom of the basket. The plate 64 could have a fixed mesh screen, or it could have a flapper valve type screen 65 hinged by pins 66, for the reason previous described.
[0079] Referring to FIG. 15, this is a table with different tubing sizes, rod sizes and baskets dimensions providing an indication of the solids storage capability of the device, and for an arbitrary number of baskets what the overall storage capacity is vs what a typical volume of solids are in a production fluid. These figures are only for helpful comparison as real well figures can vary significantly.
[0080] Referring to FIGS. 16 to 22 there is shown another embodiment of the invention. It consists of a lower connection 70 which connects to the discharge side of the pump, an upper connection 71 and a tubular housing 72. Inside the tubular member 72 is a vertical member 73, consisting of three layers, two outer layers 74,75 and an inner sandwich layer 76. Attached to the vertical sandwich layer are crescent shaped shelfs 77, these create a closed chamber 78, at the bottom of this chamber is the shelf 77 and in this shelf is a passage 79 and midway in this passage is a filter 80 of a selected mesh size, this allows the flow of fluid in the upward direction 81 through the chamber 78. Fluid flow up can also flow through the large passage 82 of the vertical sandwich assembly along the crescent flow path with no shelf 83 to another opening in the vertical sandwich 85. In the event of a shut down, fluid above the pump will fall down 86 through this device, through the pump and equalise with the fluid in the tubing annulus. Any solids 87 in the flow will collect in the closed chamber 88 and be stored there, preventing them from going into the pump discharge. Along the vertical side of the chamber are passages and filter material 89, also to help solids flow into the catchment chambers a helical flow generator 91 makes to returning solids flow in a spiral path. When pumping is recommenced, fluid will flow up following the easiest path 90, it will also flush clean the solids stored in the closed chamber 88, by flowing into the filter path 89 and 80. It will be appreciated that the solids produced with the production fluid can be different mesh sizes, so it may be advantageous to have different mesh sizes for the different shelfs, foe example, for a 12 shelf device, the upper two shelfs could be 40 mesh, the next two 60 mesh, the next two 80 mesh, the next two 100 mesh, the next two 120 mesh and last two 140 mesh
[0081] Referring to FIGS. 23 to 29 there is shown another embodiment to the sucker rod pump solids capture device. It consists of an injection moulded part. It has two halves, 100 and 101, which when folded together form a crescent shaped basket 102 which occupies about half the production tubing flow area. At the lower end of the basket thin slots have been created in the bottom of the basket, by the action of the moulding tool. A V shape tool or die from the outside creates V shaped grooves 103 on the outer most lower side of the bottom of the basket, and a V shaped inner die or tool creates V shaped grooves on the inner side of the top face of the bottom of the basket 104. The tips of 103, 104 of the dies touch each over and after the moulding process, the width of the tips equal the size of mesh. i.e 40 mesh is equal to 0.0165, 70 mesh is equal to 0.0083 and 100 mesh is equal to 0.0059. Using such opposing dies with V-shaped section grooves produces a mesh parallel screen bars; a mesh having cross bars may be produced by opposing dies having corresponding truncated pyramid features, the mesh size being determined by the size of the truncated apex of the pyramid portions of the dies.
[0082] An interlocking feature 105 locks the two halves together once folded together. The inner diameter 106 is sized to clip around the sucker rod 107, and once clipped onto the rod, cannot come away freely as it circumference extends beyond the centre line of the rod. At each end of the basket are two long spacers 107,108, which provide a spacing to connect more than one of these assemblies to another. When two or more assemblies are paired together, they are 180 degrees relative to each other, as shown by 110, 111. At there overlap they have a recess that forms a 360 channel 112 into which a clamp 113 can be installed to lock the two parts to the sucker rod. At the top an bottom of the rod a centraliser 114 is fitted to provide a stand off and protect the baskets from rubbing against the internal surface of the production tubing.
[0083] Referring to FIGS. 30 to 34 there are shown some further embodiments to the shelf filter screen. In one embodiment, the screen will consist of triangle shaped bars 120, with round bars 121 situated between them, when flow is coming up from the pump, the round bars 121 lift off from the angular face 122 and provide a large flow area 123 to better flush the basket storage area 124. In flow shut down the rods 121 would fall down and come to rest on the angular surface 122, this could be then zero flow back or have slots or grooves etc (not shown) to allow non or controlled return flow. Alternatively, a frame 130 could allow a continuous triangular wire 131 to be wrapped around it to form a filter screen on both the top side and lower side of the frame. This could be inserted into the slot 132, of the crescent shaped shelf 133.
