Patent Publication Number: US-9896891-B2

Title: Top drive operated casing running tool

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation-in-part of U.S. patent application Ser. No. 14/056,362, for “Top Drive Operated Casing Running Tool”, filed on Oct. 17, 2013, and claims the benefit of priority from the aforementioned application. 
    
    
     FIELD OF THE INVENTION 
     The field of the invention is tools that assemble and deliver tubular strings into a borehole and more particularly top drive driven tools that allow circulation, makeup and movement of the string as it is assembled into the borehole. 
     BACKGROUND OF THE INVENTION 
     In the past manipulation, threading and circulation of casing or tubulars was done with a variety of tools such as fill up and circulation tools that featured a seal to the inside or the outside of the tubular to be able to pump fluid as the tubular string was lowered into the borehole or to initially fill that last segment that was added to the string before running in. Typically the handling of a joint to be added to a string was done with elevators and the threading was accomplished with tongs. Such tools are illustrated in U.S. Pat. Nos. 6,578,632; 5,971,079; 7,028,769; 7,065,515 and 6,173,777. 
     More recently systems have been developed that employ the top drive for rotation and axial movement of a tubular joint to be made up to an existing string and advanced into the borehole. These are rather complex devices that rely on cam pairs to convert rotation to axial movement of slips that cams the slips radially outwardly or inwardly to grip the inside or the outside of a tubular. They feature opposed cam pairs to allow slip actuation with bi-directional rotation and a lock position in between to allow for release. These designs are highly complex and expensive to produce and present complications that could require significant downtime for maintenance. The design is illustrated in in U.S. Pat. Nos. 8,424,939 and 7,909,120. 
     In a first embodiment of the present invention enables selective grip and release of a tubular joint to thread a connection and to rotate a string while facilitating release to get the next joint in the string connected. The device may include a lower end seal preferably in the form of a cup seal and slips in a housing that respond to axial movement of an actuating member. The actuating member is connected to a clutched drive that is engaged for power delivery and disengaged with set down weight from the top drive. Drive rotation turns a thread that is engaged to the actuating member to move the actuating member axially in one of two opposed direction for radial extension or retraction of the slip segments. With the slips engaged the string can be rotated while lowered or lifted. With the string supported from the rig floor the top drive can radially allow the slips to retract with rotation. Those skilled in the art will have a better understanding of the present invention from the description of the preferred embodiment and the associated drawings while recognizing that the full scope of the invention is to be found in the appended claims. 
     In an alternative embodiment the components are rotationally locked to the housing of the tool as it is inserted into the casing as well as when weight is set down after the slips are extended to grab the casing. In between is a position that allows one or more parts to be rotated that engage with another part that is limited to axial movement so that a multi-ramped mandrel extends the slips to grip. When the slips are set with the needed torque the relatively rotating components are rotationally locked to the housing such that top drive rotation of the housing will turn the string rather than further trying to extend the slips, this avoiding potential damage to the casing from slip overextension. 
     SUMMARY OF THE INVENTION 
     A casing running tool is connected to a top drive with a clutch that operates with set down weight against a spring resistive force. Setting down weight with rotation in a first direction raises an actuation member that pushes the slips out radially. The weight of the string then keeps the slips in position so that the string can be picked up and the rig floor slips removed followed by lowering the string while circulating and rotating. With slips set inside the joint and the string hanging free rotating the top drive rotates the string as the string is lowered. With slips again supporting the string on the rig floor the top drive can be rotated in an opposed direction with weight set down to back off the slips and to remove it from the top joint. 
     In an alternative embodiment, spring loaded dogs can be attached to the housing to engage the casing internally or externally to facilitate extension or retraction of the slips that selectively grab the topmost of a string of casing. When the tool is suspended from the top drive, its components are rotationally locked to facilitate insertion into the casing stand on top of a string being run in the hole. Some set down weight allows top drive rotation to move a multi-ramped mandrel axially because that mandrel is rotationally locked to the housing that is held fast by the spring loaded dogs bearing on the casing. Once the slips are extended with a specified torque applied from the top drive, further setting down weight locks the components and the housing so that applied rotation with setting down weight will turn the casing string but will not torque up the slips beyond their set position which could cause stress cracks to the casing. A return spring returns the components to a rotationally locked position with respect to the housing so the process can be repeated after the slips get retracted with rotation in an intermediate position between hanging and weight fully set down. Components can be rotationally locked when driving in the string into the borehole with backpressure from circulating fluid employed to hold the components in a rotationally locked relation so that the string can be manipulated as it is inserted without slip radial movement in opposed directions. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows the device in the run in position; 
         FIG. 2  is the view of  FIG. 1  with weight set down before the spring is compressed; 
         FIG. 3  is the view of  FIG. 2  with the spring compressed just before rotation that will extend the slips; 
         FIG. 4  shows the actuating member having moved up as a result of rotation that sets the slips; 
         FIG. 5  shows the slips extended on the multiple ramps of the actuating member; 
         FIG. 6  is a close up showing three of four slips in the set position; 
         FIG. 7  is the view of  FIG. 6  with the slips in the retracted position; 
         FIG. 8  is a detailed view of the spline inside the housing wall which acts as a rotational lock when there is no set down weight from the top drive; 
         FIG. 9  is a section view of an alternative embodiment shown in the suspended position and inserted into the casing; 
         FIG. 10  is the view of  FIG. 9  with weight set down to then allow slip extension with rotation; 
         FIG. 11  is the view of  FIG. 10  after rotation that has extended the slips against the casing; and 
         FIG. 12  is the view of  FIG. 11  showing setting down weight after setting the slips to allow pushing on the casing string and rotated when running in the casing without further extending the slips. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIG. 1  a top drive TD is schematically illustrated as supporting a top sub  3  at threads  30 . The top sub  3  is rotationally locked to driving nut  1  that is captured above shoulder  32  leaving an exposed annular surface  34  on which spring  5  exerts and upward force. Driving nut  1  is rotationally locked to top sub  3  with locking balls  9  although other ways to rotationally lock can be used. Drive nut  1  has an exterior gear pattern or splines  36  that in the  FIG. 1  position are engaged with an internal gear or splines  38  on driven nut  2  and with splines  39  on an interior wall of the housing  7  when subjected to the force of spring  5 . Splines  39  are best seen in  FIG. 8  when the driving gear  1  is pushed down to expose splines  39 . Driven nut  2  is mounted to rotate in housing components  6  and  7 . Driven nut  2  is connected to actuator  10  at thread  40  such that rotation of the driven nut  2  by driving nut  1  through meshed splines  36  and  38  result in axial translation of actuator  10  into or out of the coils of spring  5 . As better seen in  FIG. 5  ramps  42  on actuator  10  engage a parallel pattern of inclined ramps  44  on slip segments  11  that are mounted for radial extension into casing  14  for contact with the interior of a casing joint  48  that is shown in  FIG. 6 . A flow passage  51  leads to outlets  55  for circulating fluid as the casing string is lowered into a borehole. A cup seal  12  has a downward orientation to hold pressure in the casing string  14  with returns coming back to the surface outside the casing string  14 . 
     To make the actuator  10  move axially, weight is set down with the top drive TD pushing the ring  50  against the top 52 of the driving nut  1 , as shown in  FIG. 2 . Further setting down weight compresses spring  5  and moves the splines  36  out of splines  39  and only into splines  38  to create meshing engagement as shown in  FIG. 3 . Note that in this position the actuator  10  is about even with the spring support surface  54 . At this point rotation of the top drive TD in one direction raises actuator  10  which pulls ramps  42  axially which results in radial movement of the slip segments  11  out until the wickers or grip profile  56  engages the tubular  14  on surface  48 . With the slips segments  11  wedged into the tubular  14 , the top drive TD is raised up so that the support slips in the rig floor that support the balance of the string below the tubular just threaded to the string, can be removed so that the top drive TD with slip segments  46  engaged to the tubular  48  now supports the string but splines have reengaged due to the return force of spring  5  and the fact that weight is no longer being set down as the entire string is hanging on the slip segments. At this point the splines on the driving nut  1  are engaged to splines  39  on the upper housing  7  so that top drive TD rotation simply turns the housing  6 ,  7  and with it the slip  11  that is secured to the housing  6 ,  7 . The top drive TD can be turned in either direction with the string weight hanging without risk of release of the slips. The driller can watch the weight indicator to determine that the hanging condition of the string is maintained before operation of the top drive TD in rotation. 
     It should be noted that spring  5  is optional and the same result can be obtained by moving a precise distance in either or both opposed directions with the top drive to get the desired engagement that allows slip extension or tubular rotation with the weight of the string hanging off the top drive as well as the release of the slips from the string when needed. 
     In order to release from the string  14  after filling and circulating through the string  14  as it is advanced into the borehole, slips on the rig floor (not shown) are set to support the string  14  from the rig floor and allow weight to be set down by lowering the top drive TD so that the  FIG. 3  position is resumed. At this point the top drive TD is made to rotate driving nut  1  and the driven nut  2  in the opposite direction than the direction that set the slip segments  46  to make the actuator  10  move back axially in a downhole direction to allow the slip segments to radially retract. When the actuator  10  moves down it will pull the slip segments  46  inward for a grip release. 
     Those skilled in the art will appreciate that spring  5  can take different forms such as a sealed volume with compressible gas inside or a stack of Bellville washers for example. The top sub  3  can be a guide for the axial movement of the actuator  10  while conducting flow through the cup seal  12 . The rotational lock with balls  9  can be splines or other structures. The design is simple and can be built economically for reliable operation. Setting down weight allows extension or retraction of the slips when accompanied by rotation from the top drive. Without setting down weight and rotating the top drive with the slips extended the tubular supported by the slips turns in tandem with the housing  6 , 7  and the slips  11  that is non-rotatably attached to it. 
     Referring now to  FIGS. 9-12  similar parts will have the same number as the above described embodiment.  FIG. 9  shows the tool inserted into the tubular  14  to the point of the travel stop  200  being positioned just above the top 202 of the tubular  14 . Actuator  10  is in a down position so that the slips  11  are retracted. Spring  18  pushes up on driving nut  1  which is rotationally locked at splines  39  to the housing  7 . Drag block housing  120  is attached to housing  7  and has drag blocks  121  biased by springs  122  against the outer wall  204  of the tubular  14 , which can be the topmost stand of a string of casing being run in or removed into or from a borehole that is not shown. Alternatively housing  120  can be inserted into the tubular  14  while still mounted to the housing  7  so that the inside wall  206  can be contacted by the drag blocks  121 . The force of springs  122  on drag blocks  121  hold the housing  7  as the top sub  3  is put into position to rotate by a downward force to release from driving nut  1  as shown in  FIG. 2 . This setting down weight compresses spring  18  to release parts for relative rotation as a kind of clutch. The top sub  3  in the  FIG. 10  position will turn in tandem with driving nut  1  and driven nut  2  and relative to the housing  7 . That rotation raises the actuator  10  that is rotationally locked but axially movable due to the presence of thread  208 . As the actuator  10  rises the ramps  42  push out the slips  11  against the tubular  14  until the needed grip torque is sensed at the top drive that is not shown. Further setting down weight on top sub  3  will engage splines  101  and  102  so that all the parts  1 ,  2  and  3  are again locked to the housing  7  which means they all turn together and further force to extend the slips against the tubular  14  is precluded. This avoid overstressing the tubular  14  after setting the slips in it during efforts to advance the tubular string and rotate it to advance the string into a borehole should there be some resistance to running in the hole such as a deviation, or hole partial collapse or other reasons to resist the advancement of the string associated with tubular  14 .  FIG. 12  shows advancing and rotating the string in a manner that will not further extend the slips  11  when setting down weight. 
     Those skilled in the art will appreciate that the drag blocks help to hold the housing fixed with respect to the tubular  14  so as to overcome friction in thread  208  when the slips  11  are extended by rotation of parts  1 ,  2  and  3  in tandem to raise the actuator  10  to extend slips  11 . For insertion in  FIG. 9 , the spring  5  insures that the parts in the housing  7  are locked to it so none of the parts relatively rotate. With some set down weight a second position is assumed where the drag blocks hold the housing  7  to the tubular  14  as items  1 ,  2  and  3  rotate together relative to the actuator  10  that cannot rotate but can move axially due to thread  208 . The slips now can be extended with the top drive to the required torque. Setting down weight further to a third position again locks items  1 ,  2  and  3  to the housing  7  so that rotating housing  7  will just rotate the tubular  14  without extending or retracting the slips  11 . Picking up allows spring  18  to get the parts  1 ,  2  and  3  back to their original positions in  FIG. 9 . 
     The above description is illustrative of the preferred embodiment and many modifications may be made by those skilled in the art without departing from the invention whose scope is to be determined from the literal and equivalent scope of the claims below: