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BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to tools for cleaning a wellbore and, more particularly, to a cleaning tool system that brushes, scrapes and selectively sprays, with high-velocity jet sprays, matter from the interior wall of a wellbore.  
         [0003]     2. General Background  
         [0004]     Cleaning a wellbore with scraping and brushing has been employed in the oil field drilling and exploration industry. The cleaning out of the wellbore is essential so, for example, the flow of drilling fluid to the annulus of the wellbore remains unobstructed between tool casings and the interior wall of the wellbore.  
         [0005]     Drilling operations use drilling fluid (sometimes referred to as drilling fluid mud) that cakes onto the wellbore. The mud is very thick and may mix with any oil residue in the wellbore annulus. Pipe scale and cement sheath can also be found adhering to the wellbore casing or liner. When cleaning the unwanted mud cake from the wellbore, the scraped or brushed mud cake (having a natural tendency to stick and adhere to surfaces) can stick, adhere and glob on surfaces of the scrapers and brushes. The scrapping and brushing is performed by metal blades and steel bristles, respectively. The mud cake may coat the blades and steel bristles and build-up thereon such that the efficiency of the scrapping and brushing is diminished.  
         [0006]     Another of the disadvantages of known wellbore cleaning devices is the accumulation of round trip delays to journal the cleaning device down hole and to remove the cleaning device, such as each time the device needs cleaning, replacing broken parts, or before, during and after drilling operations. The roundtrip delay time extends the time to complete drilling operations which increases the cost of operations.  
         [0007]     Furthermore, known wellbore cleaning devices require repeated cleaning of the brushes and scraper, thus adding additional round trip delays.  
         [0008]     In view of the above, there is a continuing need for a wellbore cleaning tool system that employs wellbore cleaning devices and a convenient and cost-effective means for cleaning said devices and the interior wall surface of the wellbore while said devices remain in the wellbore.  
         [0009]     In view of the above, there is a continuing need for a wellbore cleaning tool system that employs brushes, scrapers and a convenient and cost-effective means for cleaning the brushes, the scrapers and the interior wall surface of the wellbore while said brushes, scrapers remain in the wellbore.  
         [0010]     In view of the above, there is a continuing need for a wellbore cleaning tool system that employs brushes, scrapers and selectively actuated high-velocity jet sprays wherein the jet sprays clean the brushes, the scrapers and the interior wall surface of the wellbore while said wellbore cleaning tool remains in the wellbore.  
         [0011]     Another continuing need is for a wellbore cleaning tool system that can selectively actuate jet sprays without interrupting drilling operations.  
         [0012]     A still further need is for a wellbore cleaning tool system that can selectively actuate jet sprays during drilling operations or while allowing a continuous flow of fluid to the bottom of the wellbore and/or drill string.  
         [0013]     A still further need is to provide a wellbore cleaning tool and cleaning tool system that permits fewer trips in and out of the wellbore.  
         [0014]     A still further need is to provide a wellbore cleaning tool and cleaning tool system that can, without removing the drill string from the wellbore, select between wellbore cleaning operations and wellbore drilling operations.  
         [0015]     As will be seen more fully below, the present invention is substantially different in structure, methodology and approach from that of other cleaning tools.  
       SUMMARY OF THE PRESENT INVENTION  
       [0016]     The preferred embodiment of wellbore cleaning tool apparatus of the present invention solves the aforementioned problems in a straight forward and simple manner.  
         [0017]     The present invention contemplates a wellbore cleaning tool system for cleaning an interior surface of the wellbore comprising: a wellbore cleaning tool apparatus operable to clean a section in a wellbore with brushes, scrapers and selectively actuated high-velocity jet sprays and operable to continuously communicate fluid through a hollow center; and, a jet spray triggering tool apparatus having a jet spray triggering mechanism which is selectively operable to restrict a flow of the fluid in the jet spray triggering tool apparatus at a location below the wellbore cleaning tool apparatus wherein the restriction causes the fluid to take a path of least resistance to selectively turn on the high-velocity jet sprays while simultaneously permitting a limited amount of fluid to flow below the jet spray triggering tool apparatus.  
         [0018]     An object of the present invention is to provide a wellbore cleaning tool system with high velocity jet sprays arranged in close proximity to the brushes and the scraper and being operable to clean off and release matter built-on or accumulated on any one brush or any one scraper wherein a limited amount of the fluid is operable to flow to a drill bit (whether or not said drill bit is drilling) in the wellbore when the high velocity jet sprays are on.  
         [0019]     A further object of the present invention is to provide a wellbore cleaning tool system wherein the section being cleaned comprises one of many sections of a wellbore (for example, but not limited to, a blow-out preventer section, a wellhead wear bushing section, a liner top section, an orifice collar section or a wellbore casing wall section).  
         [0020]     A still further object of the present invention is to provide a wellbore cleaning tool system with a jet spray triggering tool apparatus that comprises a casing body having a cradle therein; and, a ported ball seat operable to be cradled in said cradle and having a cylindrical structure with a hollow center, a seat area and a plurality of through holes formed in a wall of said cylindrical structure to permit said limited amount of the fluid to flow therethrough  
         [0021]     A still further object of the present invention is to provide a wellbore cleaning tool system wherein the jet spray triggering mechanism comprises a ball operable to be circulated through the wellbore cleaning tool apparatus to said seat area to restrict the flow of the fluid.  
         [0022]     A still further object of the present invention is to provide a wellbore cleaning tool system wherein each of the high-velocity jet sprays comprise a spray head with at least one jet spray orifice; and, an internal check valve subassembly having a spring biased plunger to automatically seal close a fluid inlet port to said jet spray orifice wherein said restriction causes the fluid to take the path of least resistance which pushes said plunger from said fluid inlet port to selectively turn on the high-velocity jet spray through said at least one jet spray orifice.  
         [0023]     A still further object of the present invention is to provide a wellbore cleaning tool system wherein the internal check valve subassembly is operable to shut off automatically said fluid inlet port when pressure in said wellbore exceeds pressure of the restricted fluid.  
         [0024]     The present invention further contemplates a method of cleaning an interior surface of the wellbore comprising the steps of: communicating fluid down hole in a drill string in the wellbore; brushing matter from said interior surface while continuously communicating the fluid down hole in the wellbore; scrapping said matter from said interior surface while continuously communicating the fluid down hole in the wellbore; and, selectively spraying via jet sprays said interior surface to clean, loosen and release said matter from the interior wall of the wellbore while continuously communicating the fluid down hole in the wellbore.  
         [0025]     An object of the present invention is to provide a method for wellbore cleaning which, simultaneously, sprays brushes during the brushing step and sprays scrapers during the scraping step to loosen and release matter sticking on or adhering to or otherwise accumulating on said brushes and said scrapers.  
         [0026]     An object of the present invention is to provide a method for wellbore cleaning which further comprises the step of: drilling in said wellbore during the communicating, brushing, scraping and spraying.  
         [0027]     A still further object of the present invention is to provide a method for wellbore cleaning which floats in said wellbore, during the communicating, brushing, scraping and spraying steps, debris from a bottom of said wellbore.  
         [0028]     A still further object of the present invention is to provide a wellbore cleaning tool apparatus that is centralized in a wellbore with top and bottom non-rotating stabilizers and is adapted to be fully rotational enabling long hours of rotating and reciprocation typically associated with drilling fluid exchange operations.  
         [0029]     A still further object of the present invention is to provide a wellbore cleaning tool apparatus that provides a means for automatically cleaning the brushes and scrapers of any build-up or matter sticking or adhering to or otherwise accumulating on such brushes and scrappers.  
         [0030]     A still further object of the present invention is to provide a wellbore cleaning tool apparatus that includes a safety shut-off for shutting off the jet sprays.  
         [0031]     A still further object of the present invention is to provide a wellbore cleaning tool system that can stay in the wellbore longer.  
         [0032]     A still further object of the present invention is to provide a wellbore cleaning tool system that requires less round-trips into and out of the wellbore during drilling operations.  
         [0033]     A still further object of the present invention is to provide a wellbore cleaning tool apparatus that minimizes the number of moving parts.  
         [0034]     A still further object of the present invention is to provide a wellbore cleaning tool apparatus that includes easily replaceable brushes and scrapers.  
         [0035]     A still further object of the present invention is to provide a single wellbore cleaning tool apparatus designed for multi-use washing applications including, without limitation, washing the blowout preventer, washing the wellhead wear bushing, washing the liner top, washing the orifice collar, washing the casing&#39;s inner diameter wall.  
         [0036]     A still further object of the present invention is to provide a wellbore cleaning tool apparatus that employs an internal check valve subassembly and creates pressure differentials in the casing body of the tool apparatus to trigger the valve plunger to turn on the jets, such jets being essentially biased to a closed mode of operation.  
         [0037]     In view of the above objects, it is a feature of the present invention to provide a wellbore cleaning tool system that is relatively simple structurally and easy to use.  
         [0038]     Another feature of the present invention is to provide a wellbore cleaning tool system that is easy to install and that is selectively activated in a wellbore.  
         [0039]     Another feature of the present invention is to provide a wellbore cleaning tool system that is selectively activated in a wellbore and permits drilling operations without removing the drill string or wellbore cleaning tool from the wellbore.  
         [0040]     Another feature of the present invention is to provide a wellbore cleaning tool and wellbore cleaning system that is self-cleaning.  
         [0041]     Another feature of the present invention it to provide a wellbore cleaning tool and wellbore cleaning system that cleans during drilling operations.  
         [0042]     The above and other objects and features of the present invention will become apparent from the drawings, the description given herein, and the appended claims. 
     
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0043]     For a further understanding of the nature and objects of the present invention, reference should be had to the following description taken in conjunction with the accompanying drawings in which like parts are given like reference numerals and, wherein:  
         [0044]      FIG. 1  illustrates a partially exploded view of the wellbore cleaning tool apparatus in accordance with the present invention;  
         [0045]      FIG. 2  illustrates a cross-sectional view along the plane  2 - 2  of  FIG. 1 ;  
         [0046]      FIG. 3  illustrates a side view of the jet spray head of the wellbore cleaning tool apparatus of  FIG. 1 ;  
         [0047]      FIG. 4  illustrates a front view along the plane  4 - 4  of  FIG. 3 ;  
         [0048]      FIG. 5  illustrates a rear view along the plane  5 - 5  of  FIG. 3 ;  
         [0049]      FIG. 6  illustrates an end view along the plane  6 - 6  of  FIG. 4 ;  
         [0050]      FIG. 7  illustrates a perspective view of the jet spray head of  FIG. 3 ;  
         [0051]      FIG. 8  illustrates a side view of a valve seat;  
         [0052]      FIG. 9  illustrates a front view of the valve seat of  FIG. 8 ;  
         [0053]      FIG. 10  illustrates a cross-sectional view along the plane  10 - 10  of  FIG. 9 ;  
         [0054]      FIG. 11  illustrates an exploded view of the jet spray assembly of the wellbore cleaning tool apparatus of  FIG. 1 ;  
         [0055]      FIG. 12  illustrates a cross-sectional view along the plane  12 - 12  of  FIG. 1 ;  
         [0056]      FIG. 13  illustrates an exploded view of a set of brushes and a set of scrapers;  
         [0057]      FIG. 14  illustrates an exploded view of the wellbore cleaning tool system;  
         [0058]      FIG. 15  illustrates a side view of the ported ball seat of the wellbore cleaning tool system of  FIG. 14 ;  
         [0059]      FIG. 16  illustrates a cross-sectional view along the plane  16 - 16  of  FIG. 15 ;  
         [0060]      FIG. 17  illustrates a top view of the ported ball seat along the plane  17 - 17  of  FIG. 15 ;  
         [0061]      FIG. 18  illustrates a ball for use with the ported ball seat;  
         [0062]      FIG. 19  illustrates a perspective view of the ported ball seat of the wellbore cleaning tool system;  
         [0063]      FIG. 20  illustrates a cross sectional view of the jet triggering tool apparatus of the wellbore cleaning tool system of  FIG. 14 ;  
         [0064]      FIG. 21  illustrates a cross-sectional view along the plane  2 - 2  of  FIG. 1  with the valve plunger in a closed position;  
         [0065]      FIG. 22  illustrates a cross sectional view of the jet triggering tool apparatus of  FIG. 20  with the ball seated to trigger the jet spray assembly and with intermediate positions of the ball shown in phantom;  
         [0066]      FIG. 23  illustrates a cross-sectional view along the plane  2 - 2  of  FIG. 1  with the valve plunger in an open position as a result of the ball being seated as shown in  FIG. 22 ;  
         [0067]      FIG. 24  illustrates a diagram of a wellbore, drilling fluid pumping system, fluid flow and wellbore cleaning tool system outline for performing the method of cleaning in accordance with the present invention; and,  
         [0068]      FIG. 25  illustrates a diagram of a wellbore. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0069]     Referring now to the drawings and in particular  FIGS. 1 and 14 , the wellbore cleaning tool apparatus of the present invention will generally be referenced by the numeral  10  with the wellbore cleaning tool system being referenced by the numeral  100 . The wellbore cleaning tool apparatus  10  includes, in general, a casing body  20  adapted to be centralized in the wellbore  5  ( FIG. 24 ) via top and bottom stabilizers (NOT SHOWN), a plurality of sets of brushes  30   a  and  30   b , a plurality of sets of scrapers  40   a  and  40   b  and a plurality of sets of jet spray assemblies  50   a  and  50   b  for high-velocity jet spraying of the interior wall of the wellbore  5  for an added cleanout effect. As will be seen from the description provided below, the high-velocity jet sprays also aid in cleaning the plurality of sets of brushes  30   a  and  30   b  and the plurality of sets of scrapers  40   a  and  40   b  during cleaning operations so that any build-up of the mud cake, cement sheath, etc., when being brushed or scraped from the interior wall, on the a plurality of sets of brushes  30   a  and  30   b  and the plurality of sets of scrapers  40   a  and  40   b  can be continuously sprayed or cleaned off and released to the fluid in the annulus of the wellbore  5 .  
         [0070]     The casing body  20  includes top and bottom ends  15   a  and  15   b  for connecting the apparatus  10  in the drill string  7  to other tools, devices, such as the stabilizers (NOT SHOWN) or more drill string  7 . The top and bottom ends  15   a  and  15   b , in the exemplary embodiment are shown as threaded. Thus, apparatus  10  may be directly connected to jet triggering assembly  80  (with apparatus  10  directly on top of jet triggering assembly  80  as shown in  FIG. 14 , in which case  207  does not represent drill string or any other element but is merely a drawing convention intended to show that apparatus  10  is connected (threaded) to jet triggering assembly  80  at threads  83   a ) or apparatus  10  may be directly connected to drill string  207  interposed between apparatus  10  and jet triggering assembly  80  (again, with apparatus  10  on top (but not directly on top due to the interposed drill string  207 ) as shown in  FIG. 14 ). Also, a plurality of the apparatus  10  may be installed at various spots in a drill string yet only one jet triggering assembly  80  is required so long as the jet triggering assembly  80  is installed in the drill string below all of the plurality of apparatus  10 .  
         [0071]     Referring also to  FIGS. 1, 2 ,  12  and  13 , the plurality of sets of brushes  30   a  and  30   b , the plurality of sets of scrapers  40   a  and  40   b  and the plurality of sets jet spray assemblies  50   a  and  50   b  are slid in, affixed to and embedded in, respectively, the casing body  20 . The casing body  20  includes a cylindrically shaped structure dimensioned to be journalled down the annulus of wellbore  5  and has a linearly straight hollow center C for communicating fluid therethrough. The cylindrically shaped structure has first (top and bottom) sections  22  with a first wall thickness T 1  and second (top and bottom) sections  24  with a second wall thickness T 2  wherein the hollow center C maintains, essentially, the same diameter along the length of the casing body  20 . The ends of the second sections  24  transitioning from or to the wall thickness T 1  of the first sections  22  transition at a 45° angle.  
         [0072]     The second sections  24  have a length of approximately 8.000 inches and a diameter of approximately 5.127 inches. The first sections  22  have a length of approximately 18.000 inches and a diameter of approximately 4.370 inches. The diameter of the hollow center C is approximately 1.250 inches. In the second sections  24 , the plurality of sets of jet spray assemblies  50   a  and  50   b  are embedded or recessed in a respective cavity  25  formed in the casing body  20 .  
         [0073]     The cylindrically shaped structure further includes third (top and bottom) sections  26  and a fourth section  28 . The third sections  26  have a third wall thickness T 3  smaller than the first wall thickness T 1 . The top third section  26  is positioned immediately adjacent the top end of the fourth section  28 . The bottom third section  26  is positioned immediately adjacent the bottom end of the fourth section  28 . The third section  26  has a diameter of 3.120 inches.  
         [0074]     Since each set of brushes  30   a  and  30   b  are identical, only one such set of brushes will be described in detail. The set of brushes  30   a  includes a plurality of brush units  32   a ,  32   b ,  32   c  and  32   d  where each brush unit is essentially identical. Thus, only one such brush unit  32   a  will be described in detail. Brush unit  32   a  includes an array  35  of bristle clusters  37   a ,  37   b ,  37   c ,  37   d ,  37   e  and  37   f . The brush unit  32   a  further includes a brush chassis  33  with a plurality of holes  34  formed therein, where each hole  34  receives a respective one of the bristle clusters  37   a ,  37   b ,  37   c ,  37   d ,  37   e  and  37   f . Each bristle cluster includes a band  39  which bundles together the bristle cluster and is received or secured in hole  34 . The brush chassis  33  includes a guide or flange  36  projecting laterally from the side of the brush chassis  33 . In the exemplary embodiment, the longitudinal length of slots  42  are angled, arched or curved. Furthermore, in the preferred embodiment, a plurality of brush units  32   a ,  32   b ,  32   c  and  32   d  when installed form a 45° left hand brush array  35  and are contoured to fit in the annulus of the interior wall of the wellbore  5  without bending or crushing of the bristles of the bristle clusters  37   a ,  37   b ,  37   c ,  37   d ,  37   e  and  37   f . In the exemplary embodiment, the bristles of the bristle clusters are made of steel or other durable metal.  
         [0075]     The set of brushes  30   b  are identical to the set of brushes  30   a . However, slot  42 ′ is oriented to curve in a right handed counterclockwise direction. On the other hand, slot  42  is oriented to curve in a left handed clockwise direction. Hence, the set of brushes  30   b  are installed to create a 45° right hand brush array  35 ′.  
         [0076]     Returning again to the casing body  20 , in a top end of the fourth section  28 , a top set of slots  42  are formed therein for installation of the set of brushes  30   a  around the circumferential perimeter of the fourth section  28 . In the bottom end of the fourth section  28 , a second set of slots  42 ′ are formed therein. The second set of slots  42 ′ receive the set of brushes  30   b . The top end of the fourth section  28  has a top edge  29   a  while the bottom end has a bottom edge  29   b . Moreover, the opening of each slot  42  is along the top edge  29   a  while the opening of each slot  42 ′ is along the bottom edge  29   b.    
         [0077]     The slot  42  is contoured to track the shape of the brush chassis  33  and includes a recessed groove  43 . The recessed groove  43  receives and mates with the guide or flange  36 . Thereby, the brush chassis  33  is cradled in the slot  42  and does not fall through the slot  42 .  
         [0078]     When assembling or replacing one or more of the brush units  32   a ,  32   b ,  32   c  and  32   d , the brush chassis  33  can be easily slid in and out of its respective slot  42  via the opening. As will be seen from the description provided below, in the exemplary embodiment, the brush units  32   a ,  32   b ,  32   c  and  32   d  of the set of brushes  30   a  are locked into their respective slot  42  via the bracelet clamp  45  of the set of scrapers  40   a  clamped to the top third section  26 . Likewise, the brush units of the set of brushes  30   b  are locked into their respective slot  42 ′ via the bracelet clamp  45  of the set of scrapers  40   b.    
         [0079]     Referring still to  FIGS. 12 and 13 , since each set of scrapers  40   a  and  40   b  are identical, only one such set of scrapers  40   a  will be described in detail. The set of scrapers  40   a  includes a two-piece bracelet clamp  45  having integrated thereon an array of circumferentially spaced blade units  44   a ,  40   b ,  44   c ,  44   d ,  44   e  and  44   f . The two-piece bracelet clamp  45  clamps together the spaced-apart blade units  44   a ,  40   b ,  44   c ,  44   d ,  44   e  and  44   f  around the top third section  26 . Likewise, the set of scrapers  40   b  are clamped circumferentially around the bottom third section  26 .  
         [0080]     The bracelet clamp  45  includes two separate semi-circular sections  46   a  and  46   b . The bracelet clamp  45  when secured or fastened together has an inner circumference that tracks the outer circumference of the third section  26  of the casing body  20 . The two semi-circular sections  46   a  and  46   b  includes first and second (right and left) aligned hole sets  47   a  and  47   b  intended to receive fasteners  48   a  and  48   b , respectively, such as a screw or bolt, to fasten or clamp together the two semi-circular sections  46   a  and  46   b . Loosening and removing the fasteners  48   a  and  48   b  allow the set of scrapers  40   a  to be removed and/or replaced when worn or damaged. The length of the bracelet clamp  45  extends from the bottom of the second section  24  to the top edge  29   a  of the fourth section. In view of the foregoing, fastening or clamping the bracelet clamp  45  locks the brush units  32   a ,  32   b ,  32   c  and  32   d  of the set of brushes  30   a  by closing the opening to slot  42  and serves as a retainer cap to maintain the brush units  32   a ,  32   b ,  32   c  and  32   d  in their respective (angled) slot  42 .  
         [0081]     In the preferred embodiment, the scrapers are not spring loaded. Standard scrapers used in the industry often use spring loaded scrapers; and, spring loaded scrapers could be used with this tool  10 .  
         [0082]     Referring now to  FIGS. 2-11 , the sets of jet spray assemblies  50   a  and  50   b  will now be described in detail. However, since each of the jet spray assembly of the set  50   a  and the set  50   b  is identical, only one such jet spray assembly  50   a  will be described. The jet spray assembly  50   a  comprises a spray head  51  having two jet spray orifices  52   a  and  52   b  and an internal check valve subassembly  60 . The spray head  51  includes two (top and bottom) recessed holes  54   a  and  54   b  adapted to receive fasteners  56   a  and  56   b , respectively. The fasteners  56   a  and  56   b  are screws or blots with heads that are adapted to be recessed in the holes  54   a  and  54   b . In the exemplary embodiment, the spray head  51  has rearwardly projecting guide prongs  58  intended to align with holes formed in a valve seat  62  nestled in the second section  24  behind the spray head  51 . The spray head  51  further includes a center aperture  59  between the two jet spray orifices  52   a  and  52   b.    
         [0083]     The internal check valve subassembly  60  includes the valve seat  62  having a front side mated with the spray head  51  and a back side dimensioned to be seated in the cavity  25  in the second section  24 . The back side has a fluid inlet port  64  has a coupler  64   a  adapted with a recessed groove  66  for receipt of an O-ring  68 . The front side of the valve seat  62  has an elongated opening  70  with a gasket  72  placed between the spray head  51  and such front side. The center axis of the elongated opening  70  is aligned with the center axis of the fluid inlet port  64 . The center axis of the fluid inlet port  64  is also aligned with the center aperture  59 . The fluid inlet port  64  is aligned with a fluid exchange port in the casing body  20  (section  24 ). The fluid inlet port  64  is shown as one with the fluid exchange port which is not separately numbered.  
         [0084]     The internal check valve subassembly  60  further comprises a valve plunger  74  having a plunger head  75  and a plunger shaft  76 . The valve plunger  74  is spring biased to a closed position ( FIGS. 2 and 21 ) via spring  78  wound around plunger shaft  76  and presses against the surface around the center aperture  59 . The plunger shaft  76  is adapted to be received in the center aperture  59 . The valve plunger head  75  is generally shaped as a pyramid. The apex of the pyramid when in the closed position is received in the fluid inlet port  64  such that fluid flowing in the hollow center of the casing body  20  is prevented from passing out of the fluid inlet port  64  and into the valve seat  62 . The internal check valve subassembly  60  will remain closed so that the jet spray orifices  52   a  and  52   b  will remain closed, as well.  
         [0085]     In the preferred embodiment, a first set of jet spray assemblies  50   a  are embedded in the casing body  20  at a location above the set of brushes  30   a  and the set of scrapers  40   a . In the exemplary embodiment, the first set of jet spray assemblies  50   a  includes two jet spray assemblies  50   a  spaced  1800  from the other. On the other hand, the second set of jet spray assemblies  50   b  are embedded in the casing body  20  at a location below the set of brushes  30   b  and the set of scrapers  40   b . In the exemplary embodiment, the second set of jet spray assemblies  50 S includes two jet spray assemblies  50   b  spaced  1800  from the other. However, the second set of jet spray assemblies  50   b  are offset from the first set of jet spray assemblies  50   a  by 90°. Thus, the plurality of sets of jet spray assemblies  50   a  and  50   b  project high velocity jet sprays from the casing body  20  at 0° (360°), 90°, 180°, and 270°. As can be appreciated, additional jet spray assemblies may be included.  
         [0086]     When moving from drilling to completion, the wellbore  5  needs to be cleaned. Commonly, jets are placed on every tool body for each transition. However, this becomes a problem when going down hole.  
         [0087]     Referring now to  FIG. 14 , the wellbore cleaning tool system  100  is shown. The system  100  includes the wellbore cleaning tool apparatus  10  and the jet triggering assembly  80  coupled at a location in the drill string  7  below the wellbore cleaning tool apparatus  10 . In the embodiment of  FIG. 14 , the jet triggering tool apparatus  80  is preferably positioned anywhere along the drill string  7  below the wellbore cleaning tool apparatus  10  but before the drill bit  110 . In operation, the jet triggering tool apparatus  80  is constructed and arranged to selectively trigger the opening or closing of the internal check valve subassembly  60  which turns the high-velocity jet sprays ON or OFF, respectively. In  FIG. 23 , the internal check valve subassembly  60  is open to permit the flow of fluid through the fluid inlet port  64  (and, it is open due to the ball  105  being seated in the jet triggering assembly  80  as shown in  FIG. 22  and the back pressure created thereby when fluid flows in C in the direction shown in  FIG. 23 ). In  FIG. 21 , the internal check valve subassembly  60  is closed to stop the flow of fluid through the fluid inlet port  64  (and it is closed as the ball  105  is not seated in the jet triggering assembly  80  as shown in  FIG. 20 ).  
         [0088]     Referring now to  FIGS. 15-20 , the jet triggering tool apparatus  80  comprises casing body  82  having a hollow center C′ adapted to allow fluid to flow therethrough down to the drill bit  110  before, during and after cleaning operations. In other words, the jet triggering tool apparatus  80  is constructed and arranged to allow for a continuous flow of fluid to the drill bit  110  or other tools located down stream, as needed. The casing body  82  (for illustrative purposes) is shown to have a top-end coupler  83   a  which is threaded, as shown in the cut-away portion, in a manner to mate with the bottom end coupler  15   b  of the wellbore cleaning tool apparatus  10  or the bottom end coupler of any interposed drill string  7 . Below the top-end coupler  83   a , the casing body  82  has a cradle  85  formed therein for receipt of a ported ball seat  90 . The casing body  82  (for illustrative purposes) is shown to have a bottom-end coupler  83   b  which is threaded, as shown in the cut-away portion, for attachment of another tool. In the example, the drill bit  110  is shown immediately below the casing body  82  or more drill string  7 .  
         [0089]     The ported ball seat  90  provides a means for triggering the internal check valve subassembly  60  from the first mode of operation to the second mode of operation when ball  105  is seated therein, as best seen in  FIG. 22 . The ported ball seat  90  includes a cylindrical structure  94  having a hollow center C 2  formed in the center of its longitudinal length or axis. The ball  105  may be a float Baker-Lite ball. The cylindrical structure  94  has a plurality of circumferential grooves  94   a  formed therein. The plurality of circumferential grooves  94   a  receive O-rings  99  ( FIG. 22 ).  
         [0090]     The top end inner diameter ID T  of the hollow center C 2  gradually tapers at approximately 30° from 2.062 to 0.9375 inches. Thereafter, the inner diameter  11 D of the hollow center C 2  is the same (0.9375 inches) until a predetermined distance D 1  from the bottom end. At the bottom end, the inner diameter slopes approximately 45° for slightly less than 0.2000 of an inch from 0.9375 to approximately 0.7500 inches. The bottom end inner diameter ID B  is approximately 0.7500 inches. The gradually tapering inner diameter provides a ball seat area  96  for seating the ball  105  therein, as best seen in  FIG. 22 . The length of the cylindrical structure  94  is approximately 5.000 inches and the outer diameter OD is approximately 2.406 inches.  
         [0091]     Additionally, the wall structure of the cylindrical structure  94  has formed therein a plurality of spaced apart through holes  98  each having a longitudinal axis that is parallel with the longitudinal axis of the cylindrical structure  94 . The through holes  98  extend from the top end to the bottom end of the cylindrical structure  94  and permit the flow of fluid in the hollow center C to flow therethrough. The through holes  98  are spaced apart approximately 45° with a diameter of 0.2500 to 0.2450 inches. In the preferred embodiment, the inner diameter of the through holes  98  is significantly smaller than the inner diameter ID of hollow center C 2 .  
         [0092]     In the exemplary embodiment, there are eight (8) through holes  98  which are constructed and arranged to permit a sufficient amount of drilling fluid to flow though the ported ball seat  90  down to drill bit  110  such as during drilling operations. Therefore, the wellbore cleaning tool apparatus  10  does not need to be removed. Hence, any delays for trips in and out of the wellbore to install or de-install the wellbore cleaning tool apparatus  10  is effectively eliminated. Moreover, the amount of fluid flowing downstream through the through holes  98  can be controlled by closing one or more of the through holes  98  before installing system  100  down hole.  
         [0093]     The jet triggering tool apparatus  80  may include a float valve (NOT SHOWN) directly below the ported ball seat  90  to allow for reverse circulating.  
         [0094]     The operation of the internal check valve subassembly  60  in combination with the jet triggering tool apparatus  80  will now be described.  
         [0095]     In a first mode of operation, the internal check valve subassembly  60  is closed as best seen in  FIGS. 2 and 21 . The bias spring force exerted by the spring  78  biases the apex of the pyramid of the plunger head  75  in the fluid inlet port  64  such that fluid flowing in the hollow center C of the casing body  20  is prevented from passing out of the fluid inlet port  64  and into the valve seat  62 . Thereby, the internal check valve subassembly  60  is closed and the high velocity jet sprays through orifices  52   a  and  52   b  are OFF. The first mode of operation maintains the jet sprays OFF.  
         [0096]     It should be noted, the spring biasing force is stronger than a first predetermined PSI (pressure per square inch) in the hollow center C of casing body  20 . Thereby, fluid flowing in the casing body  20  is not squirted, jetted, streamed or sprayed out through the orifices  52   a  and  52   b  until the pressure in the hollow center C exceeds the first predetermined PSI. In this mode, the ball  105  is not seated in ported ball seat  90  of the jet triggering tool apparatus  80 .  
         [0097]     In a second mode of operation, once the first predetermined PSI is exceeded, the fluid in the hollow center C exerts a sufficient counter force to push (trigger the transition of) the plunger head  75  out of the fluid inlet port  64  such that some fluid flowing in the hollow center C of the casing body  20  flows from the fluid inlet port  64  and into the valve seat  62 . Thereby, the internal check valve subassembly  60  is open and the high velocity jet sprays through the orifices  52   a  and  52   b  are ON.  
         [0098]     The PSI in the hollow center C is increased above the first PSI by floating ball  105  down casing body  20  to the jet triggering tool apparatus  80  such that ball  105  is seated in the ball seat area  96 . When the ball is seated in the ball seat area  96 , a restriction is created causing some of the fluid to take the path of least resistance through the internal check valve subassembly  60  (noting that some of the fluid can still flow through holes  98 ). The internal check valve subassembly  60  remains ON until the pressure in the annulus of wellbore  5  outside of the casing body  20  is greater than the second predetermined PSI or the pressure in the casing body  20  is below the second predetermined PSI whereby the spring biasing force closes the fluid inlet port  64  with the plunger head  75 .  
         [0099]     In the second mode, fluid from the center C of casing body  20  is squirted, jetted, streamed or sprayed out at a high velocity through the orifices  52   a  and  52   b . For example, upon completion of the jetting application, the ball  105  may be extracted by reverse circulation. Thus, the high-velocity jet sprays are selectively turned OFF. The ball  105  serves as the jet spray triggering mechanism to restrict the fluid flow to turn the sprays ON and to un-restrict the fluid flow to turn the sprays OFF.  
         [0100]     In a third mode of operation, if the second predetermined PSI in hollow center C is exceeded in the annulus of the wellbore  5 , the internal check valve subassembly  60  is constructed and arranged to immediately shut OFF by exerting pressure though the center aperture  59  on plunger shaft  76 . The valve plunger  74  is thereby pushed (triggering the transition of) the plunger head  75  to a closed position ( FIGS. 2 and 21 ). The apex of the pyramid when in the closed position is received in the fluid inlet port  64  However, in the third mode, fluid in the annulus of the wellbore  5  is prevented from reaching in the hollow center C. The third mode of operation is a safety shut-off feature to prevent a reversed flow of the jet stream.  
         [0101]     If all internal check valve subassembly  60  are constructed and arranged to trigger or transition between modes on the same first predetermined PSI and second predetermined PSI, then all jet sprays would be effectively turned on and off essentially simultaneously with a single jet spray triggering mechanism (ball  105 ).  
         [0102]     In view of the foregoing, the design described above can be varied. For example, the spring  78  can be replaced by removing the spray head  51 . Therefore, the strength of the spring  78  can be varied, as needed for different wellbore  5  characteristics, to increase or decrease the biasing force proportionately to at least the first predetermined PSI. The number and size of the through holes  98  may also be varied.  
         [0103]     The number and size of jet spray orifices  52   a  and  52   b  in the spray head  51  may be varied. Furthermore, the casing bodies  20  and  82  may be varied by changing the scheduled pipe size. In most applications, a 9⅝ inch schedule pipe and a 7 inch schedule pipe will be used.  
       Cleaning Operations  
       [0104]     Referring now to  FIG. 24 , the wellbore  5  (through which drilling operations occur) includes a plurality of sections wherein the top section is a riser section  6   a  which in turn is followed by a blow-out preventer section  6   b . The blow-out preventer (BOP) section  6   b  is followed by an intermediate casing  6   c  which in turn is followed by a casing liner  6   d.    
         [0105]     The wellbore cleaning tool system  100  brings a third dimension of cleaning to scraping and brushing when cleaning out the wellbore  5  including below the blow-out preventer  6   b  or  8   b . The wellbore cleaning tool apparatus  10  is effective in removing mud cake, oily residue, cement sheath, and pipe scale (hereinafter referred to as “matter”). The wellbore cleaning tool apparatus  10  is designed to provide superior contact at all angles of inclination and may be oriented pin-up or pin-down. Furthermore, the wellbore cleaning tool apparatus  10  is fully rotational and centralized by non-rotating top and bottom stabilizers (NOT SHOWN) to protect the wellbore from wear and enabling long hours of rotating and reciprocation typically associated with drilling fluid exchange operations.  
         [0106]     During normal drilling operations, the drilling fluid path  120  is shown. Drilling fluid from fluid tank  122  is pumped via pump source  124  using pump gauges  126 , in the direction of ARROWS A, down the wellbore  5  through a preliminary length of drill string  7  to the wellbore cleaning tool system  100 . At the wellbore cleaning tool system  100 , the fluid further flows down the hollow center C, through center C′ of the jet triggering tool apparatus  80  (with the ported ball seat  90 ), then out of the drill bit  110  and up the annulus of the wellbore  5 , in the direction of ARROWS B, without any restrictions. In general, the fluid is pumped by the pump source  100  such that, at the wellbore cleaning tool apparatus  10 , the PSI is below the first predetermined PSI. During the normal drilling operation, the internal check valve subassembly  60  will remain closed so that the jet spray orifices  52   a  and  52   b  are OFF.  
         [0107]     The fluid flowing in the direction of ARROWS B is recycled by circulating the fluid, in the direction of ARROWS C, out through the annulus of the wellbore  5  through shale shackers  128  and a filter unit  130 . The fluid flowing through the filter unit  130  is sent back to the fluid tank  122  where it is stored until recycled.  
         [0108]     As can be ready seen, the wellbore cleaning tool system  100  does not interrupt or restrict the flow of the drilling fluid during normal operations. Thus, one (or more) of well bore cleaning tool  10  of the wellbore cleaning tool system  100  can be installed in the wellbore  5  until needed.  
         [0109]     The drilling fluid path described herein in relation to  FIG. 24  is for illustrative purposes only. The production of drill fluid and the circulation thereof has been well established in the oil field exploration industry and does not require further explanation. In  FIG. 25  another wellbore arrangement is shown. The wellbore  5 ′ includes a riser section  8   a  followed by a blow-out preventer (BOP) section  8   b . The blow-out preventer (BOP) section  8   b  is followed by a wellhead wear bushing  8   c  where the inner diameter of the wellbore decreases immediately below the bushing  8   c . The section below the wellhead wear bushing  8   c  terminates at a liner top  8   d . The liner top  8   d  is followed by a section of casing wall  8   e  having a inner diameter smaller than the liner top  8   d . The casing wall  8   e  has an orifice collar  8   f . In operation, the system  100  is operable to clean and wash one or more of the BOP section  8   b , the wellhead wear bushing  8   c , the liner top  8   d , the orifice collar  8   f  and casing wall  8   e  while allowing fluid to continuously flow all the way to the end of the drill string or bottom of the wellbore  5 .  
         [0110]     Cleaning of the wellbore  5  with scraping and brushing can take place essentially continuously during drilling operations since system  100  can be installed anywhere on the drill string above the drill bit  110 . Accordingly, two-dimensional cleaning, via brushing and scraping, can take place continuously. The continuous flow of fluid floats removed (brushed and/or scraped) debris to the top of the wellbore  5 . Even if not drilling, the cleaning operations can take place in the wellbore  5  with the benefits of the drilling fluid recirculated up the annulus to assist in washing the “matter” being knocked off of the scrapers, brushers and inner wellbore  5 .  
         [0111]     To add the third dimension of cleaning, high-velocity jet sprays through orifices  52   a  and  52   b  are turned ON. To turn the high-velocity jet sprays ON, the ball  105  is pumped down, in the direction of ARROWS A, with the fluid flowing through the hollow center C of the casing body  20  to ported ball seat  90 . Since the ball  105  has an OD greater than the ID of the ball seat area  96 , the ball  105  is seated or cradled in the recessed area of the ball seat area  96  restricting or sealing off the flow of fluid through hollow center C 2 . The restriction causes some of the fluid to take the path of least resistance which is through the internal check valve subassembly  60  and the jet spray orifices  52   a  and  52   b  as the force (PSI) exerted by the fluid is stronger than spring  78  (again, noting that some of the fluid can flow through the holes  98 ). Thereby, plunger head  75  is moved out of the fluid inlet port  64 , which then becomes open. As can be appreciated, the restriction increases the PSI of the fluid flowing in hollow center C above the first predetermined PSI, thereby triggering the transition from the first mode to the second mode.  
         [0112]     In the preferred embodiment, limited fluid flow through the ported ball seat  90  via the plurality of spaced apart through holes  98  to the drill bit  110  is permitted after the ball  105  has been seated in the ball seat area  96 . The application of the ball  105  seated in ball seat area  96  and the fluid being re-directed through the jets spray orifices  52   a  and  52   b  is observed remotely by the operator via pump gauges  126 . Flow rates are established before the ball  105  is pumped down to the ported ball seat  90 . After the ball  105  is pumped down the same flow rate will be used. An increase in fluid pressure (PSI) occurs when the ball  105  is seated in the ported ball seat  90 .  
         [0113]     In the preferred embodiment, no more than 20 bbls. per minute and no more than 3000 PSI is applied.  
         [0114]     During cleanout operations, the wellbore cleaning tool apparatus  10  brushes via the sets of brushes  30   a  and  30   b  and scrapes via the sets of scrapers  40   a  and  40   b  the “matter” on the interior wall of the wellbore  5 . Thereby, “matter” may buildup or stick on the brushes and scrapers. The third dimension of cleaning by the jet spray orifices  52   a  and  52   b  to produce high-velocity jet sprays loosen and clean “matter” on the interior wall and on the sets of brushes  30   a  and  30   b  and the sets of scrapers  40   a  and  40   b.    
         [0115]     Upon completion of the cleanout operations, the ball  105  is extracted from the ported ball seat  90 . The ball extraction takes place by reverse circulating the ball  105  up the tool apparatus  10  and casing  7 . Alternately, the ball  105  can be extracted by allowing the ball  105  to float up the tool apparatus  10  and drill string  7  when a float valve (NOT SHOWN) is used in the tool apparatus  10  which will not allow for reverse circulation.  
         [0116]     While not wishing to be bound by theory, a ball  105  of 0.875 is pumped down at approximately 11 feet per second as per pumping  10  bbls. minute. Once the ball  105  is seated, approximately two-thirds of the fluid will still flow through the through holes  98  down to the drill bit  110  allowing for debris to be pushed up the annulus from the bottom of the wellbore  5  or drill bit  10 . The projected restriction in the fluid is approximately 5 ft. per second as per pumping bbls. minute.  
         [0117]     Because many varying and differing embodiments may be made within the scope of the inventive concept herein taught and because many modifications may be made in the embodiment herein detailed in accordance with the descriptive requirement of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.

Summary:
A wellbore cleaning tool system includes a plurality of brushes and scrappers supported by or mounted to a casing body to clean an interior wall of a wellbore. The cleaning tool system includes selectively actuated high-velocity jet sprays to aid the cleaning of the interior wall of a wellbore by enhance the loosening and releasing of mud cake, oily residue, cement sheath, and pipe scale. The jet sprays also aid in the cleaning operation performed by and efficiency of the brushes and scrappers by spraying, loosening and releasing matter (mud cake, oily residue, cement sheath, and pipe scale) adhering to or sticking on the brushes and scrapers.