Abstract:
A pressure activated bendable tool assembly having a longitudinal centerline, the tool assembly comprising an adapter sub for connection to an end of a tubular member having a bore extending longitudinally therethrough and a plurality of bend elements positioned in a serial relationship also having a bore extending longitudinally therethrough, the bore being in fluid communication with the bore of the adapter sub and each adjacent bending element. The bend elements are axially retained by a plurality of retainer sleeves. The retainer sleeves limit the amount the bend elements may be longitudinally displaced from each other about a preselected side of the retainer sleeve element. A head-sub forms a distal end of the tool assembly opposite of the adapter sub. The tool assembly bends with respect to the longitudinal centerline a preselected amount upon inducing a pressure differential between the respective bores of the adapter sub, the bend elements, and the head-sub and the ambient pressure of the tool assembly.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Not Applicable 
     MICROFICHE APPENDIX 
     Not Applicable 
    
    
     FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
    
    
     BACKGROUND OF THE INVENTION 
     This invention generally relates to tools used in the exploration and production of oil and gas, and relates more particularly to downhole well tools capable of being bent, or deflected, to a pre-selected angle with respect to a longitudinal reference line upon internal pressurization of the tool to achieve or enhance certain downhole operations. 
     BRIEF SUMMARY OF THE INVENTION 
     A pressure a activated bendable tool assembly having a longitudinal centerline, the tool assembly comprising an adapter sub for connectedly adapting the tool assembly to an end of a tubular member, the adapter sub having a bore extending longitudinally therethrough and having a means for providing a fluid connection between the tubular member and the tool assembly. A first bend element having a bore extending longitudinally therethrough, the bore being in fluid communication with the bore of the adapter sub. A second additional bend element having a bore extending therethrough for accommodating a portion of a bend element positioned longitudinally proximate to the second additional bend element. At least one retainer sleeve for axially retaining the first and second bend elements, the retainer sleeve further having a means for limiting the amount the first and second bend elements may be longitudinally displaced from each other about a preselected side of the retainer sleeve element. A head-sub means for forming a distal end of the tool assembly opposite of the adapter sub. Wherein the tool assembly bends with respect to the longitudinal centerline a preselected amount upon inducing a pressure differential between the respective bores of the adapter sub, the bend elements, and the head-sub and the ambient pressure of the tool assembly. 
     A preselected number of bending elements and retainer sleeves may be installed to achieve the desired total amount of arc in which the tool is to bend upon being pressurized. 
     The head-sub may be replaced with a jetting sub containing a jet nozzle for performing jetting operations. The subject tool assembly is particularly suitable for use in carrying out jetting operations or entry operations in multilateral wellbores or horizontal wellbores when connected to coiled tubing or composite coiled tubing. 
     Preferably the bend elements have external shoulders which coact with internal tangs on the sleeve retainers to axially restrain the bending elements along a preselected side to cause the bend elements to form an arc about the longitudinal axis of the tool assembly upon being pressurized. Preferably the shoulders have notches therein to allow the tangs of the retainer sleeves to slip about the bending elements and to be rotatably positioned thereabout. 
     Preferably set screws or other lock means are provided for non-bindingly securing the retainers about their respective bend elements, and adaptor and head sub if appicable, to prevent the retainer sleeves from rotating out of position by engaging the slots in the shoulders of the bending elements. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a cross-sectional front view of an embodiment of the disclosed bending tool assembly having a jetting head. 
     FIG. 2A is an end view of an end-sub forming a jetting head shown in the assembly illustrated in FIG.  1 . 
     FIG. 2B is a cross-sectional view of the end-sub taken along line  2 B— 2 B as illustrated in FIG.  2 A. 
     FIG. 3A is an end view of a bend element shown in the assembly illustrated in FIG.  1 . 
     FIG. 3B is a cross-sectional view of the bend element taken along line  3 B— 3 B as illustrated in FIG.  3 A. 
     FIG. 4A is an end view of a retainer sub shown in the assembly illustrated in FIG.  1 . 
     FIG. 4B is a cross-sectional view of the retainer-sub taken along line  4 B— 4 B as illustrated in FIG.  4 A. 
     FIG. 5 is a conceptual view of a bending tool assembly in a primary wellbore and being deflected to allow it to enter a secondary laterally-oriented wellbore. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to FIG. 1 of the drawings showing an embodiment of a pressure activated bending tool assembly  2 . Assembly  2  includes a jetting-sub  4 , a bend element  20 , two retainer-subs, alternatively referred to as sleeve retainers,  40 , and an adapter  50  for connecting the assembly to another tool or to a connector that has been attached to a section of coiled tubing. The components can be machined or fabricated of steel, stainless steel, or any material having adequate chemical resistance and structural strength to survive conditions expected to be encountered in subterranean wells. Only one bend element  20 , also referred as a bend unit, has been depicted to simplify the illustration. However, it is contemplated that a plurality of bend elements would be installed in a serial sequence in order to obtain the desired amount of bend, or lateral deflection upon the tool assembly being pressurized. 
     Jetting head  4  has a jet-receiving bore  6  for accommodating commercially available jetting nozzles. Such jetting nozzles are available in a wide variety of configurations and sizes and therefore the receiving bore will be designed to sealingly engage and secure such jetting nozzles. Jet receiving bore  6  is in communication with jet passage  7  which in turn is in communication with internal bore  8  which provides a flow path for the fluid medium to be used for jetting, typically water. Within internal bore  8 , proximate to opposite end face  18 , are O-rings  10  installed within respective grooves  12 . The exterior of jetting head  4  has a relieved outer diameter portion  14  and a larger outer diameter shoulder  16 . 
     Bend element  20  is provided with a mandrel  22  sized to be slidably accommodated by internal bore  8  of jetting head  4  and to be sealed thereabout by O-rings  10 . Adjacent first face  26 , which is designed to abut face  18  of jetting head  4 , there is a slight groove  24  about mandrel  22  which allows for mandrel  22  to better clear the edge of mandrel receiving bore  30  when multiple bend elements are utilized and the tool assembly is pressurized to induce a bending of the components. The exterior of bend element  20  is provided with a reduced outer diameter  28  that resides between a pair of raised circumferential shoulders  25  in which end face  26  defines the outer end of one shoulder and a second end face  36  which in turn defines the outer end of the second shoulder. Extending generally longitudinally through bend element  20  is a fluid passage bore  38  of at least one pre-selected internal diameter. The fluid passage bore has an enlarged portion  30  beginning at end face  36  and extending toward mandrel  22 . Within enlarged bore  30  is at least one and preferably two grooves  34  for receiving respective O-rings  32 . 
     Adapter sub  50  is provided with a mandrel  52  having a longitudinal fluid passage bore  56  extending throughout adapter sub  50 . Opposite mandrel  52 , a bore  56  is preferably provided with a threaded portion  54  in order for the adapter to be attached to another tool, or to a connector that has been installed upon the end of a section of coiled tubing. A reduced outer diameter region  59  is located approximately midway of adapter  50 . An increased outer diameter defining a shoulder  58  is positioned between region  59  and mandrel  52 . Mandrel  52  is sized and configured, preferably essentially identical to mandrel  22  of bend element  20  and mandrel  52  is received and sealed within bore  30  of bend element  20 . 
     Retainer-sub  40  is designed to be slidably installed about, at least a large portion of the entire exterior of bend element  20 , portions of jetting head  4 , and adapter  50 . Retainer-sub  40  is essentially a hollow cylinder having an internal bore  42 . Retainers, such as set screws  44  are removably installed within threaded retainer receptacle bores  46 . As can be seen, retainers  44  protrude into internal bore  42  and are essentially flush with the outside surface of retainer-sub  40  when fully installed. Located diametrically opposite of retainers  44  are preferably rectangular-shaped tangs  43  which protrude into internal bore  42 . 
     Referring now to FIGS. 2A and 2B which show more detail of representative jetting head  4  shown in FIG.  1 . Jetting head  4  is particularly suited for liquid, or slurry, jetting operations conducted with the subject bendable tool. Typically threaded jet receiving bore  6  is positioned at a pre-selected angle α from a longitudinal reference line for accommodating a pre-selected jet of a particular orifice diameter and spray profile that are well known in the art and commercially available generically illustrated as jet nozzle  5 . An angle between 35° to 45° is commonly -used, however any angle can be used to best suit the operation being undertaken. Furthermore, more than one such bore  6  may be provided in order to accommodate jets in a plurality of locations so as to provide jetting from preselected locations within jetting head  4 . For example, jetting bores/jets may be located on the same side of the jetting head or, jetting bores may be positioned on sides opposite from each other, or at any other circumferential and/or longitudinal location with respect to each other as deemed appropriate. Also multiple jetting bores/jets may be strategically provided to counteract reactive forces generated by spray exiting the primary working jets which causes the jetting head, as well as the attached tubing string, to move away from the targeted work area in the absence of such counteracting jets. 
     An arcuate notch  15  of a predetermined angle β, or alternatively a slot or channel of pre-selected width, is provided from face  18  through shoulder  16  to the smaller relieved shoulder  14 . Notch  15  is for allowing the passage of tang  43  when installing retainer sub  40  shown in FIGS. 1,  4 A, and  4 B. The function and interaction of tang  43  and shoulder  16  will be described in further detail in due course. 
     Referring now to FIGS. 3A and 3B which shows bend element  20  of FIG. 1 in more detail. As mentioned previously, bend element  20  is designed to be used singularly as shown in FIG. 1 or to be used in a group of several such elements to form a string of bend elements of a pre-selected number to provide the total desired bend, or total lateral reach, that the jetting head, or the lower most component of the tool assembly, needs to travel in a lateral direction with respect to the longitudinal centerline of the tool in order to perform a given operation upon pressurizing the tool assembly. 
     Dimension A is the length of the tapered portion of mandrel  22 . Dimension B is the I.D. of receiving mandrel receiving bore  30 . Dimension C is the O.D. of the free end of mandrel  22  and dimension D is the O.D. of the fixed end of mandrel  22 . Dimension E is the length of shoulders  25 . Dimension F is the spacing between shoulders  25 . Dimension K is the O.D. of shoulders  25 . 
     An essential feature of bend element  20  is hollow mandrel  22  and its co-action with receiving bore  30  of an adjacent bend element  22  in a string of bend elements is that the mandrel has a taper about its outside diameter. The inside diameter of the bore passing through mandrel  22  is not critical beyond it having a large enough bore to provide a desired fluid flow rate needed in relation to the pressures to be used. The taper preferably begins in the proximity of groove  24  of the fixed end of the mandrel and decreases in diameter as it extends outwardly toward the free end of mandrel  22 . Dimension D of the fixed end is the largest O.D. of the taper and Dimension C of the free end is the smallest O.D. of the taper. That is the largest portion of the taper begins at Dimension D and the outside diameter of mandrel  22  gradually decreases until reaching the minimum outside diameter of mandrel  22  designated as Dimension C. Angle β in FIG. 3 is the angle of arc of notches  15  in shoulders  25 . Such notches serve the same function as notch  14  of jetting head  4  in that it allows a tang  43  located within bore  42  of retainer-sub  40  (shown in FIGS. 4A and 4B) to pass through the notch when installing retainer-subs  40  about a pair of adjacent bend elements. 
     Such a taper thereby allows the bend element  22  to laterally deviate a pre-selected amount of arc, typically 3° per bend segment  20 , from an imaginary longitudinal reference line extending through bore  38 , or several sequentially positioned bores  38  when a multiplicity of such bend elements are used, and/or bore  8  in the case of mandrel  22  of the last bend element  20  installed into bore  8  of jetting head  4 . 
     Referring now to FIGS. 4A and 4B which are more detailed views of retainer-sub  40 . Retainer-sub  40  has a pre-selected O.D.  48 . Internal bore  42  has a nominal I.D. of dimension I which does not include tang  43  that protrudes into bore  42  by the distance denoted by dimension J. Tang  43  has a pre-selected circumference corresponding to angle φ. As mentioned earlier, retainer receptacle bores  46  preferably are threaded to accommodate retainers such as brass set screws  44 , not shown in FIG. 4, see FIG. 1, that when installed are preferably flush to the outer diameter of retainer sub  40 . Screws  44  need not be a threaded brass screw, and can be made of any material having sufficient strength to secure retainer-sub  40  about: a pair of bend elements  20 ; a bend element  20  and a jetting sub  4 ; or a bend element  20  and an adapter sub  50  as shown in FIG.  1 . Depending on the particular application in which the subject tool is to be used, the screws may need to be of steel or similar high strength material. As can also be seen in FIG. 1, the region between tangs  43  accommodates shoulder  16  of jetting head  4  adjacent shoulder  25  of bend element  20 , and the other shoulder  25  of bend element  20  and adjacent shoulder  58  of adapter sub  50 . The sizing of the above components is such that installation of retainer-sub  40  is easily achieved while maintaining the desired amount of clearance to allow for a predetermined amount of lateral movement of bend element  20  upon pressurization of the tool assembly. 
     In order to assemble a tool assembly having a pre-selected number of bend elements, a jetting head for example is selected and the mandrel of the bend element is installed into receiving bore  8  of the jetting head. Notch  15  of the jetting head and notches  27  of the bend element are aligned with each other, then a retainer-sub is slipped over the bend element and partially over the jetting sub by aligning tang  43  of the retainer sub with the notches  15  and  27 . Upon the tangs clearing the notches the retainer-sub is rotated 180° with respect to the longitudinal axis so that the retaining screws are now aligned with and positioned above the notches. 
     The retaining screws are installed so as to project into notches  15  and  27 . However, the screws are not bottomed out against the bend elements but are positioned such that the bend elements have a requisite amount of movement yet do not bind the elements. The lower most section of the retaining screws reside at least partially within the notches so that the retainer sub can not rotate about the longitudinal axis. The top most section of the retaining screws are preferably flush with the outside diameter to prevent snagging of the tool when being run downhole. The retaining screws can be made of brass or any suitable material and are preferably secured with a suitable commercially available thread locking compound. Means other than set screws can be used to retain the retainer sub in positions such as engagement dogs or dowel pins for example. Regardless, of the retaining means selected, care should be exercised in not allowing the installation to bind the subs and thus interfere with the desired amount of movement of the retainer and jetting subs. One tang  43  of the retainer sub is now positioned in portion  14  of the jetting sub and the other tang  43  of the retainer sub is positioned in the reduced outside diameter portion  28  of the bending element wherein shoulder  16  and shoulder  25  are sandwiched between the two tangs as shown in FIG.  1 . The installation process is repeated until the pre-selected number of bending elements and retainer subs have been assembled with the last component usually being the adapter sub thereby completing the tool assembly. 
     After the tool assembly has been installed onto a section of coiled tubing, such as tubing  60  shown in FIG. 5, the tool assembly is run downhole through, for example, a casing  70  having a packer  80  to seal the annulus between the casing and the wellbore. Upon reaching the desired depth, the tool assembly  2  is pressurized by way of surface pumps pressurizing a working fluid such as water and routing it through the coiled tubing through the internal bores of the tool assembly. Upon tool assembly  2  being pressurized internally, for example around 5000 pounds per square inch gauge, the individual bend segments will make an arc, or bend, toward wellbore  82  and jetting of the casing or well bore can begin. The bending is the result of the pressurization imparting forces that tend to move the individual bending elements away from each other longitudinally, but tangs  43  longitudinally retain adjacent shoulders  25  as well as shoulder  16  of the jetting sub  4  and shoulder  58  of the adapter sub. Because the tangs inhibit longitudinal motion on such respective sides of the bending elements, the opposite sides of the bending elements, the sides where retaining screws  44  are located, are forced longitudinally away from each other and due to the clearance between the tapered mandrel  22  and the respective bore which tapered mandrel  22  resides within. This results in an arc of approximately 3° per each bend element when the bend elements and the other components are constructed with the dimensions given in the example below. Thus, jetting head  4  is caused to move toward wellbore  82  by the cumulative amount of bend, or arc, of all the bend elements installed in tool assembly  2  upon sufficient internal pressurization of tool assembly  2 . 
     An example of a tool assembly  2  for jetting was constructed wherein the geometry of the tool was as shown in the drawings with the various dimensions being as follows: 
     Dimension A—1.00 inch (25.4 mm) 
     Dimension B—0.75 inch (19.1 mm) 
     Dimension C—0.72 inch (18.3 mm) 
     Dimension D—0.74 inch (18.8 mm) 
     Dimension E—0.50 inch (12.7 mm) 
     Dimension F—1.00 inch (25.4 mm) 
     Dimension G—0.49 inch (12.3 mm) 
     Dimension H—1.03 inch (26.2 mm) 
     Dimension I—1.51 inch (38.4 mm) 
     Dimension J—0.10 inch (2.5 mm) 
     Dimension K—1.50 inch (3.8 mm) 
     Dimension L—1.50 inch (3.8 mm) 
     Dimension M—3.00 inch (7.6 mm) 
     Dimension N—1.75 inch (44.5 mm) 
     Dimension O—1.13 inch (28.7 mm) 
     Dimension P—2.02 inch (51.31 mm) 
     Angle α—45° 
     Angle β—39.5 to 40.0° 
     Angle φ—38.5 to 39.0° 
     When constructing the various components of the tool assembly to the above dimensions, each bend element being approximately 3 inches in overall length, provided approximately 3° of bend, or arc, per bend element within the bending tool assembly. The arc is primarily determined by the outside diameter and the taper of mandrel  22 , the inside diameter and length of bore  30 , and the distance between the end of bore  30  and the tip of mandrel  22 , which in the embodiment shown in the drawings corresponds with the length of fluid passage bore  38 . By considering these dimensions when constructing the bend elements, the arc and therefore the reach of each bending segment can be pre-calculated. Thereafter, a proper number of bend elements can be combined in order to obtain the total reach needed for the tool assembly to conduct a given job. Of course a tool assembly be could built using bend elements having differing bend characteristics, but it somewhat complicates the calculation of what the total reach would be for the tip of that tool assembly after having pre-selected the number of each differing bend elements. Table  1  shows the corresponding top angle, side reach, and tool length for each number of bend elements and retainer subs that could form a tool assembly as shown and described herein and having the dimensions set forth below. Although Table  1  shows  10  bend elements and  11  retainer subs, more could be added to form a bending tool assembly of a desired length provided limitations due to reactive forces from jetting are observed or compensated for. 
     
       
         
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                 NUMBER 
                 NUMBER 
                   
                   
                   
               
               
                 OF 
                 OF 
                 TIP BEND 
                 SIDE 
                 TOOL 
               
               
                 BEND 
                 RETAINER 
                 ANGLE 
                 REACH 
                 LENGTH 
               
               
                 ELEMENTS 
                 SUBS 
                 (DEGREES) 
                 inches (mm) 
                 inches (mm) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 0 
                 1 
                 3 
                 0.10 (2.5)  
                  5 
                 (127) 
               
               
                 1 
                 2 
                 6 
                 0.32 (8.1)  
                  7 
                 (177) 
               
               
                 2 
                 3 
                 9 
                 0.63 (16.0)  
                  9 
                 (228) 
               
               
                 3 
                 4 
                 12 
                 1.06 (26.9)  
                 11 
                 (279) 
               
               
                 4 
                 5 
                 15 
                 1.59 (40.3)  
                 13 
                 (330) 
               
               
                 5 
                 6 
                 18 
                 2.24 (56.9)  
                 15 
                 (381) 
               
               
                 6 
                 7 
                 21 
                 3.01 (76.4)  
                 17 
                 (431) 
               
               
                 7 
                 8 
                 24 
                 3.90 (99.0)  
                 19 
                 (483) 
               
               
                 8 
                 9 
                 27 
                 4.92 (124.9) 
                 21 
                 (533) 
               
               
                 9 
                 10 
                 30 
                 6.07 (139.6) 
                 23 
                 (584) 
               
               
                 10 
                 11 
                 33 
                 7.37 (187.2) 
                 25 
                 (635) 
               
               
                   
               
             
          
         
       
     
     if radial jetting is not being conducted, such as when jetting axially or when using the subject bending tool for other operations such as a means for entering laterally-orieted wellbores as shown in FIG. 5, any number of bend elements can be used if an adequate internal hydraulic working pressure is achievable to overcome the effective weight of the tool assembly which is dependent upon the vertical and horizontal force components due to gravity acting upon the tool assembly. 
     When jetting or performing operations in which the exiting of liquids from a jetting nozzle, for example, causes a reaction force that tends to move the tip of the tool assembly away from the target surface. This back thrust can be quite powerful depending on the operating pressure, flow rate, and density of the working fluid as well as any fluid that may be present in the area surrounding the tool assembly. Therefore, it is recommended to calculate the maximum number of bend elements that can be installed within a tool assembly before the back thrust becomes great enough to move at least the jetting portion of the tool assembly away from the target surface. Furthermore, the orientation of the tool assembly in the wellbore, or more accurately the positions of the jetting nozzles when using the tool assembly in jetting operations, as well as the horizontal orientation of the well bore in non-vertical wells, often referred to as lateral or horizontal wellbores, has an effect on the amount of back thrust that a tool assembly can withstand prior to the tool assembly being forced away from the target when jetting. The following equations offer a practical prediction of the maximum number of bend units of a given length that can be assembled to form a bending tool assembly for a given operating pressure and a pre-selected jetting nozzle: 
     
       
           F= 0.052{square root over (P)} 
       
     
             N   =     15.104                 RS          P       Ql                 sin                   α   °                                  Q= 25.36{square root over (P)} 
     
       
         
           
             N 
             = 
             
               0.596 
                
               
                   
               
                
               S 
                
               
                 R 
                 
                   dl 
                    
                   
                       
                   
                    
                   sin 
                    
                   
                       
                   
                    
                   
                     α 
                     ° 
                   
                 
               
             
           
         
                 
         
             
         
      
     
     Where: 
     N=Number of Bend Elements or Units 
     P=Operating Pressure (psi) 
     S=Average Diameter of Tapered Mandrel (inches) 
     l=Length of Bend Sections Including Jet Tips (inches) 
     R=½ I.D. of Sleeve (inches) 
     α=Angle of Jet Nozzle 
     Q=Flow Rate of Fluid (gal/min) 
     d=I.D. of Jet Nozzle (inches) 
     F=Backthrust (lbs) 
     In light of the above calculations, it can be appreciated that the effective weight of the tool assembly can become quite significant when the tool assembly is being used in horizontal, or highly deviated, well bore applications and operating pressure, design criteria, and the number of bend elements must be considered and selected as appropriate for the direction in which the active jetting nozzle, or nozzles are positioned and are to be directed. For example, if the jetting head is laying essentially in a horizontal position and the jetting nozzle is directed upward at a 90 degree angle with respect to longitudinal center line of the tool assembly, the reactive forces of jetting could quite easily push the jetting head away from the targeted work area at a given pressure due to the gravitational forces acting on the tool assembly in the same direction as the reactive force from the jetting in a more pronounced fashion than if the tool assembly were positioned in a vertical wellbore. 
     A bending tool assembly constructed in accordance with the data set forth in the preceding Table 1 will when having a single jet with a liquid having the characteristics set forth in Table 2 below, will provide an exemplary bending tool that can be used to demonstrate the desired qualities and benefits offered by the subject bending tool assembly. 
     
       
         
               
               
               
             
               
               
               
               
             
           
               
                   
                 TABLE 2 
               
               
                   
                   
               
               
                   
                 # of Jet Nozzles 
                 1 
               
               
                   
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Fluid Weight 
                 8.3 lbs/gal 
                 (1.00 kg/l) 
               
               
                   
                 Jet Nozzle Diameter 
                 0.092 inches 
                 (2.337 mm) 
               
               
                   
                 Discharqe Coefficient 
                 0.95 
               
               
                   
                 Pressure Differential 
                 5000 psig 
                 (351.5 kg/cm 2 ) 
               
               
                   
                 Q 
                 17.0104 gpm 
                 (64.38 1/min) 
               
               
                   
                 Thrust 
                 62.5464 lbs 
                 (278.21 N ) 
               
               
                   
                 Weight Link 
                 1.5 lbs 
                 (6.67 N ) 
               
               
                   
                 Angle of Jet 
                 40° 
               
               
                   
                 Diameter of pressured area 
                 0.75 in 
                 (19.05 mm) 
               
               
                   
                 Diameter of Links 
                 1.5 in 
                 (38.10 mm) 
               
               
                   
                 Bends per unit 
                 3 
               
               
                   
                 Length of unit 
                 2 in 
                 (50.80 mm) 
               
               
                   
                   
               
             
          
         
       
     
     Referring now again to FIG. 5 of the drawings, the subject bending tool need not be used solely to downhole jetting purposes but can also be used to guiding a tool string into a lateral or horizontal wellbore. In FIG. 5, a production casing  70  secured by a packer  80  set in vertical or main wellbore  82  is shown. Located below packer  80  is lateral wellbore  84  which joins main wellbore  82  at juncture  86 . Coiled tubing  60 , or other type of tubular conduit, has a pre-selected orienting tool  62  attached thereto. A bending tool assembly  2  having a jetting sub  4 , or in addition to or in the alternative, having a miscellaneous tool  64  being attached to the end of tool assembly  2  is shown. 
     In practice, the tool string is run downhole through casing  70  until reaching such a depth that the orienting tool is activated to radially rotate the end of the tool so as to properly orient the bottom of the tool string for entry into lateral wellbore  84 . Coiled tubing  60  is then internally hydraulically pressurized to a sufficient pressure so as to cause bending tool  2  to bend or curve sufficiently to cause the bottom of the tool string to enter lateral wellbore  84  at the juncture  86  upon further running the tool string deeper. Such bending can be achieved without the need to raise or lower the workstring longitudinally, or to weight and unweight the workstring, in order to activate the bending of the tool assembly as such bending is done with internal hydraulic pressure and not physical manipulation of the tool string. This makes the subject tool assembly very attractive when the use of coiled tubing is called for in operations to be conducted within either horizontal or vertical wellbores. 
     It will be appreciated and understood that variations of the disclosed and illustrated embodiments of the subject invention may be made without departing from the spirit and scope of the invention as claimed.