Abstract:
Methods and apparatus for spinning a pipe using a flexible belt. The spinner utilizes a single actuation mechanism contained within a rigid body to engage the pipe and tension the belt. The pipe is engaged by one or more pivoting arms that are locked into place by pins attached to the actuation mechanism interfacing with slots in the pivoting arm and spinner body. Once the arms are locked in place, the belt is tensioned and can be driven to rotate the pipe. The single actuation mechanism is preferably embodied by a linear actuator connected between a pivoting arm and a moveable motor. The pivoting arm is spring biased so that the arm pivots before the motor is moved. The spinner may use two pivoting arms, or one pivoting arm and one stationary arm.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     Not applicable.  
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002]     Not applicable.  
       BACKGROUND OF THE INVENTION  
       [0003]     The present invention relates to methods and apparatus for rotating tubular members, such as drill pipe. More particularly, the present invention relates to methods and apparatus for spinning a drill pipe during connection and disconnection of the drill pipe in a drill string.  
         [0004]     In rotary drilling applications, a tubular drill string is formed from a series of connected lengths of drill pipe. The individual lengths of drill pipe are joined by threaded connections. During the drilling and completion of a well, the drill string must occasionally be pulled from the well and reinstalled. The process of pulling or installing the drill string is referred to as “tripping.” During tripping, the threaded connections between the lengths of drill pipe are connected and disconnected as needed. The connecting and disconnecting of adjacent sections of drill pipe (referred to as making or breaking the connection, respectively), involves applying torque to the connection and rotating one of the pipes to fully engage or disengage the threads.  
         [0005]     In modern wells, a drill string may be thousands of feet long and typically is formed from individual thirty foot sections of drill pipe. Even if only every third connection is broken, as is common, hundreds of connections have to be made and broken during tripping. Thus, it can be seen that the tripping process is one of the most time consuming and labor intensive operations performed on the drilling rig.  
         [0006]     Currently, there are a number of devices that seek to speed tripping operations by automating or mechanizing the process of making and breaking a threaded pipe connection. These devices include tools known as power tongs, iron roughnecks, and pipe spinners. Many of these devices are complex pieces of machinery that require two or more people to operate and require multiple steps, either automated or manual, to perform the desired operations. Additionally, many of these devices grip the pipe with teeth that can damage the drill pipe and often cannot be adjusted to different pipe diameters without first replacing certain pieces, or performing complex adjustment procedures.  
         [0007]     Thus, the embodiments described herein are directed to methods and apparatus for gripping and spinning a pipe for making or breaking a connection that seek to overcome these or various other limitations of the prior art.  
       SUMMARY OF THE PREFERRED EMBODIMENTS  
       [0008]     The preferred embodiments include methods and apparatus for spinning a pipe using a flexible belt. The spinner utilizes a single actuation mechanism to engage the pipe and tension the belt. The pipe is engaged by one or more pivoting arms that are locked into place by pins attached to the actuation mechanism and interfacing with slots in the pivoting arm and spinner body. Once the arms are locked in place, the belt is tensioned and can be driven by a motor to rotate the pipe. The single actuation mechanism is preferably embodied by a linear actuator connected between a pivoting arm and a moveable motor. The pivoting arm is spring biased so that the arm pivots and locks into place before the motor is moved. The spinner may use two pivoting arms, or one pivoting arm and one stationary arm.  
         [0009]     In one embodiment, the spinner includes a pair of pivoting arms supported on a rigid body. In this embodiment, a flexible belt is wound around a rotating drive motor and around rollers attached to each arm. The drive motor is slidably mounted to the body. Linear actuators, such as hydraulic cylinders, connect the pivoting arms to the drive motor. As the actuators extend, a spring biases the arms toward a closed position such that the arms close around a pipe before the motor begins to slide and apply tension to the belt. Slots on the arms and the body interface with a pin on the end of the cylinders to prevent the arms from opening when the actuators are extended.  
         [0010]     In another embodiment, the pipe spinner comprises a body, an arm pivotally connected to the body and adapted to engage a pipe with a flexible belt, a drive assembly moveably connected to the body and adapted to engage the flexible belt, and a linear actuator connected to the arm and the drive assembly, wherein the linear actuator is adapted to move the arm to engage the pipe and move the drive assembly to apply tension to the flexible belt. The spinner may also include a locking mechanism adapted to maintain the engagement of the arm and the pipe, where the locking mechanism is actuated by the linear actuator and may include a first slot on the arm, which is adapted to guide a pin attached to one end of the linear actuator, and a second slot on the body, which is adapted to guide the pin. In certain embodiments, the body encloses the pivoting arm, the drive assembly, and the linear actuator. The pipe spinner may also include a pin connecting one end of the linear actuator to the motor assembly, wherein the pin is adapted to slide within a slot on the body, and a spring adapted to urge the pivoting arm to an engaged position with the pipe.  
         [0011]     In an alternate embodiment, a device for rotating a tubular member comprises a body and a pivoting arm connected to the body and having a closed position engaging the tubular with a flexible belt and an open position not engaging the tubular. A moveable drive assembly is connected to the body and has a first position not applying tension the flexible belt and a second position applying tension to the flexible belt. A linear actuator is adapted to move the pivoting arm from the open position to the closed position and the moveable drive from the first position to the second position, wherein the moveable drive is moved to the second position after the pivoting arm is moved to the closed position.  
         [0012]     Another embodiment includes a method for operating a pipe spinner comprising pivoting an arm to surround a pipe with a flexible belt, moving a drive assembly to apply tension to the flexible belt, and activating the drive assembly to drive the belt and rotate the pipe, wherein the arm is pivoted and the drive assembly is moved by a single linear actuator. The method may also include engaging a locking mechanism to maintain the position of the arm, wherein the locking mechanism is engaged by the single linear actuator. In alternative methods, a spring may urge the arm to surround the pipe and the pipe spinner comprises two pivoting arms and two linear actuators.  
         [0013]     Thus, the present invention comprises a combination of features and advantages that enable it to substantially improve the gripping an spinning of a tubular member. These and various other characteristics and advantages of the present invention will be readily apparent to those skilled in the art upon reading the following detailed description of the preferred embodiments of the invention and by referring to the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]     For a more detailed understanding of the present invention, reference is made to the accompanying Figures, wherein:  
         [0015]      FIG. 1  is a schematic view of one embodiment of a dual armed pipe spinner shown in the open position;  
         [0016]      FIG. 2  is a schematic view of the spinner of  FIG. 1  shown in a closed position; and  
         [0017]      FIG. 3  is a schematic view of another embodiment having a single armed pipe spinner shown in the open position.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0018]     In the description that follows, like parts are marked throughout the specification and drawings with the same reference numerals, respectively. The drawing figures are not necessarily to scale. Certain features of the invention may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in the interest of clarity and conciseness.  
         [0019]     The preferred embodiments of the present invention relate to methods and apparatus for rotating a tubular member, such as a pipe. The present invention is susceptible to embodiments of different forms. There are shown in the drawings, and herein will be described in detail, specific embodiments of the present invention with the understanding that the present disclosure is to be considered an exemplification of the principles of the invention, and is not intended to limit the invention to that illustrated and described herein. In particular, various embodiments of the present invention provide a number of different spinner configurations. Reference is made to the application of the concepts of the present invention to rotating drill pipe, but the use of the concepts of the present invention is not limited to these applications, and can be used for any other applications including the rotation of cylindrical bodies and in particular to the manipulation of other members having threaded connections. It is to be fully recognized that the different teachings of the embodiments discussed below may be employed separately or in any suitable combination to produce desired results.  
         [0020]     Referring now to  FIG. 1 , spinner assembly  100  includes body  110  supporting two pivoting arms  120 , slidable motor assembly  130 , linear actuators  140 , bias members  150 , and flexible belt  160 . The structure of spinner assembly  100  is essentially mirrored about its longitudinal centerline. Body  110  includes a substantially flat base  111  having walls  112  substantially surrounding three sides of body  110 . Base  111  includes vertical guide walls  113 , linear slots  114 , motor slot  115 , locking slots  116 , and mounts for pivots  126 . Locking slots  116  have a curved portion  117 , which has an axis of curvature located at pivot  126 , and a straight portion  118  substantially parallel to linear slots  114 . Curved portion  117  and straight portion  118  intersect at transition point  119 . Body  110  also preferably includes a top portion (not shown) which has similar features to base  111  and is mounted to walls  112 , forming a substantially enclosed apparatus.  
         [0021]     Pivoting arms  120  attach to body  110  at pivot  126 . Arms  120  include a substantially flat base  121  having a guard wall  122 , slot  123 , and protruding end portion  124 . Idler rollers  125  attach to base  121  and are free to rotate relative thereto. Slot  123  has a forward end  127  and a rearward end  128 .  
         [0022]     Motor assembly  130  includes sliding plate  131  that supports motor  132 . Motor  132  is preferably a hydraulic or air motor that drives belt sprocket (pulley)  133 . Motor assembly  130  is supported in a slidable relationship with body  110  and is aligned with motor slot  115 . Sliding plate  131  also includes attachment points for pins  134  that move within linear slots  114 .  
         [0023]     Two linear actuators  140 , which may preferably be hydraulic cylinders, include a rod end  141  and barrel end  142 . Rod end  141  accepts rod end pin  134 , which slides in linear slot  114 . Barrel end  142  accepts pin  143 , which slides in locking slot  116  and arm slot  123 . It is understood that actuators  140  may also be reversed where the rod end and barrel end are opposite as shown and described.  
         [0024]     Bias members  150  include spring barrels  151  containing springs  152  that tend to bias arms  120  toward a closed position. Springs  152  exert a force on the protruding end  124  of the arms  120 . This force acts against body  110  and tends to pivot arms  120  about pivot  126  toward the closed position. The force exerted by springs  152  can be overpowered by the force applied by actuators  140 .  
         [0025]     A flexible, flat belt  160 , runs over motor sprocket  133 , idler rollers  125 , and around pipe  170 . Belt  160  is preferably constructed from a flexible, strong material such as Kevlar®, or some other durable, high strength, woven, composite material. In the preferred embodiments, belt  160  grips pipe  170  without damaging the outer surface of the pipe and provides sufficient friction to rotate the pipe as desired.  
         [0026]     Pivoting arms  120  are pivotally attached to body  110  by pivot connections  126 . Motor assembly  130  is adapted to slide back and forth inside the body  110  where its motion is guided by walls  113  and is limited by rod end pins  134  sliding in linear slots  114 . The rod end pins  134  attach to the rod ends  141  of linear actuators  140 . The barrel ends  142  of linear actuators  140  are attached to body  110  and pivoting arms  120  by barrel end pins  143  interfacing with locking slots  116  and arm slots  123 .  
         [0027]     In  FIG. 1 , spinner  100  is shown in the open position with arms  120  fully opened, springs  152  compressed, linear actuators  140  fully retracted, motor assembly  130  in a forward position, and belt  160  fully relaxed and in a position ready to wrap around the pipe  170 .  FIG. 2  shows spinner  100  in a closed position with arms  120  closed, springs  152  extended, linear actuators  140  extended, motor assembly  130  in a rearward position, belt  160  wrapped around pipe  170  and in tension ready to spin the pipe. In this closed position, motor  132  rotates sprocket  133 , which transfers motion through belt  160  to rotate pipe  170 .  
         [0028]     In order for the spinner to move from the open position shown in  FIG. 1  to the closed position shown in  FIG. 2 , a valve (not shown) controlling the supply of fluid to linear actuators  140  is switched to start the extension of the cylinders. At this point (the open position) the rod ends  141  of the actuators  140  with rod end pins  134  are in the forward ends of linear slots  114  and the barrel ends  142  with barrel end pins  143  are in the outside end of the curved portion  117  of locking slots  116  and in the rearward end  128  of arm slots  123 .  
         [0029]     As actuators  140  start to extend, bias members  150  push arm end portions  124  causing the rotation of arms  120  about pivots  126 . This motion rotates actuators  140  about rod end pins  134  and moves barrel end pins  143  through curved portion  117  of locking slot  116  towards transition point  119 . Idler rollers  125  move toward each other as arms  120  rotate toward the closed position. As barrel end pins  143  reach transition point  119 , arm slots  123  align with straight portions  118  of locking slots  116  and are substantially in line with linear slots  114 .  
         [0030]     From this intermediate position, further extension of actuators  140  move barrel end pins  143  through the straight portions  118  of locking slots  116  and from the rearward end  128  to the forward end  127  of arm slot  123 . Once barrel end pins  143  reach the forward end  127  of arm slot  123 , arms  120  are essentially locked in place until actuators  140  are retracted. The forces on arms  120  from belt tensioning and operation of the apparatus will tend to pivot the arms toward the open position, but these forces are resisted by barrel end pins  143  being retained by the straight portion  118  of locking slot  116 .  
         [0031]     Rod end pins  134  move toward the rearward end of linear slots  114 , moving motor assembly  130  rearward and tightening belt  160  around pipe  170 . Belt  160  can tighten around any diameter pipe that can be engaged by arms  120 . No input or adjustment from the operator is required.  
         [0032]     Once fully in the closed position shown in  FIG. 2 , motor  132  can be actuated so as to rotate sprocket  133 , which moves belt  160  that rotates pipe  170 . Locking slots  116  and arm slots  123  constrain barrel end pins  143  to operate as a safety lock preventing arms  120  from opening as pipe  160  is pushed by belt  170  against rollers  125 . Once arms  120  are locked in the fully closed position, they can only open after barrel end pins  143  are retracted by linear actuators  140 .  
         [0033]     Returning spinner assembly  110  to the open position from the closed position, which releases pipe  170 , operates in the opposite sequence. As actuators  140  start retracting, bias members  150  maintain arms  120  in the closed position until rod ends  141  with rod end pins  134  reach the forward ends of linear slots  114 . At this point, motor assembly  130 , including with motor  132  and sprocket  133 , is in a forward position where belt  160  is loose.  
         [0034]     Further retraction of actuators  140  moves barrel ends  142  and barrel end pins  143  through transition point  119  and into curved portion  117  of locking slots  116 . Arms  120  rotate about pivot  126  to their open position and collapse springs  151  into their barrels  152 . Once arms  120  fully open, pipe  160  is released and spinner  100  is ready for a new operation.  
         [0035]     The unique actuation sequence, which closes and locks the pipe in place before tensioning the belt allows the device to handle a wide range of pipe sizes with one belt length and without any additional adjustment by the operator. The arrangement of the slots provide a self-locking feature that eliminates certain complexities found in other belt-type spinners that include a separately engaging lock feature to retain the pipe in the spinner.  
         [0036]     Referring now to  FIG. 3 , an alternative spinner assembly  200  is shown having only one pivoting arm  220  mounted to a rigid body  210 . This simplified device is especially suitable for spinning tubular members that are oriented in a horizontal position, such as would be found in shop conditions, but is also equally adaptable for use on vertically oriented tubular members.  
         [0037]     Spinner assembly  200  includes body  210  supporting one pivoting arm  220 , a slidable motor assembly  230 , a linear actuator  240 , a bias member  250 , and a flexible belt  260 . Body  210  includes a substantially flat base  211  having walls  212  substantially surrounding three sides of body  210 . A single idler puller  213  is mounted to base  211  and acts as a stationary arm. Base  211  also includes linear slots  214  and  236 , motor slot  215 , locking slot  216 , and a mount for pivot  226 . Locking slot  216  has a curved portion  217  with a axis of curvature located at pivot  226  and a straight portion  218  substantially parallel to linear slots  214 . Curved portion  217  and straight portion  218  intersect at transition point  219 . Body  210  also preferably includes a top portion (not shown) which has similar features to base  211  and is mounted to walls  212 , forming a substantially enclosed apparatus.  
         [0038]     Pivoting arms  220  attach to body  210  at pivot  226 . Arms  220  include a substantially flat base  221  having a guard wall  222 , slot  223 , and protruding end portion  224 . Idler roller  225  attaches to base  221  and is free to rotate relative thereto. Slot  223  has a forward end  227  and a rearward end  228 .  
         [0039]     Motor assembly  230  includes sliding plate  231  that supports motor  232 . Motor  232  is preferably a hydraulic or air motor that drives belt sprocket (pulley)  233 . Motor assembly  230  is supported in a slidable relationship with body  210  and is aligned with motor slot  215 . Sliding plate  231  also includes guide pin  235 , which interfaces with linear slot  236 , and an attachment point for rod end pin  234  that move within linear slot  214 .  
         [0040]     Linear actuator  240 , which may preferably be a hydraulic cylinder, includes a rod end  241  and barrel end  242 . Rod end  241  accepts rod end pin  234 , which slides in linear slot  214 . Barrel end  242  accepts pin  243 , which slides in locking slot  216  and arm slot  223 . It is understood that actuator  240  may also be reversed where the rod end and barrel end are opposite as shown and described.  
         [0041]     Bias member  250  includes spring barrel  151  containing spring  152  that tends to bias arm  220  toward a closed position. Spring  252  exerts a force on the protruding end  224  of arm  220 . This force acts against body  210  and tends to pivot arm  220  about pivot  226  toward the closed position. The force exerted by spring  252  can be overpowered by the force applied by actuator  240 .  
         [0042]     A flexible, flat belt  260 , runs over motor sprocket  233 , idler rollers  213  and  225 , and around pipe  270 . Belt  260  is preferably constructed from a flexible, strong material such as Kevlar®, or some other durable, high strength, woven, composite material. In the preferred embodiments, belt  260  grips pipe  270  without damaging the outer surface of the pipe and provides sufficient friction to rotate the pipe as desired.  
         [0043]     Pivoting arm  220  is pivotally attached to body  210  by pivot connection  226 . Motor assembly  230  is adapted to slide back and forth inside the body  210 , where its motion is guided and limited by guide pin  235  in linear slot  235  and rod end pin  134  in linear slot  214 . The rod end pin  234  attaches to the rod end  241  of linear actuator  240 . The barrel end  242  of linear actuator  240  are attached to body  210  and pivoting arm  220  by barrel end pin  243  interfacing with locking slot  216  and arm slot  223 .  
         [0044]     In  FIG. 3 , spinner  200  is shown in the open position with arm  220  fully opened, spring  252  compressed, linear actuator  240  fully retracted, motor assembly  230  in a forward position, and belt  260  fully relaxed and in a position ready to wrap around the pipe  270 . In the open position the rod end  241  of the actuator  240  is in the forward end of linear slot  214  and the barrel end  242  is in the outside end of the curved portion  217  of locking slot  216  and in the rearward end  228  of arm slot  223 . Linear actuator  240  is extended to move spinner  200  from the open position shown in  FIG. 3  to a closed position. Spinner  200  operates in the same manner as spinner  100  of  FIG. 1  and  FIG. 2 .  
         [0045]     As actuator  240  starts to extend, bias member  250  pushes arm end portion  224  causing the rotation of arms  220  about pivot  226 . This motion rotates actuator  240  about rod end pin  234  and moves barrel end pin  243  through curved portion  217  of locking slot  216  towards transition point  219 . Idler roller  225  moves toward idler roller  213  as arm  220  rotates toward the closed position. As barrel end pin  243  reaches transition point  219 , arm slot  223  aligns with straight portion  218  of locking slot  216  and is substantially in line with linear slot  214 .  
         [0046]     From this intermediate position, further extension of actuator  240  moves barrel end pin  243  through the straight portions  218  of locking slot  216  and from the rearward end  228  to the forward end  227  of arm slot  223 . Once barrel end pin  243  reaches the forward end  227  of arm slot  223 , arm  220  is essentially locked in place until actuator  240  is retracted. The forces on arm  220  from belt tensioning and operation of the apparatus will tend to pivot the arm toward the open position, but these forces are resisted by barrel end pin  243  being retained by the straight portion  218  of locking slot  216 .  
         [0047]     Rod end pin  234  moves toward the rearward end of linear slot  214 , moving motor assembly  230  rearward and tightening belt  260  around pipe  270 . Belt  260  can tighten around any diameter pipe that can be engaged by arm  220 . No input or adjustment from the operator is required. Once fully in the closed position, motor  232  can be actuated so as to rotate sprocket  233 , which moves belt  260  and rotates pipe  270 . Locking slot  216  and arm slot  223  constrain barrel end pin  243  to operate as a safety lock preventing arms  220  from opening as pipe  260  is pushed by belt  270  against roller  225 . Once arm  220  is locked in the fully closed position, they can only open after barrel end pin  243  is retracted by linear actuator  240 .  
         [0048]     The embodiments set forth herein are merely illustrative and do not limit the scope of the invention or the details therein. It will be appreciated that many other modifications and improvements to the disclosure herein may be made without departing from the scope of the invention or the inventive concepts herein disclosed. Because many varying and different embodiments may be made within the scope of the inventive concept herein taught, including equivalent structures or materials hereafter thought of, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptive requirements of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.