Pipe handling apparatus

Information

  • Patent Grant
  • 6533519
  • Patent Number
    6,533,519
  • Date Filed
    Thursday, July 20, 2000
    24 years ago
  • Date Issued
    Tuesday, March 18, 2003
    22 years ago
Abstract
A pipe handling apparatus for transporting a joint of pipe between a position adjacent a pipe storage rack and a rig floor elevated above the pipe storage rack is provided. The pipe handling apparatus includes a support frame, substantially horizontally disposed platform supported by the support frame having a pipe receiving groove formed therein for receiving the joint of pipe, a carriage member, and a pusher member. The carriage member is movable from a lowered position wherein the joint of pipe which is positioned in the pipe receiving groove of the platform is supported in a substantially horizontal position and a raised position wherein the carriage member supports a first end of the joint of pipe at an elevated position relative to an opposed second end of the joint of pipe. The pusher member is movable along the pipe receiving groove between a retracted position and an extended position. In the retracted position, the pusher member is positioned near the second end of the pipe receiving groove to laterally support the joint of pipe when the first end of the joint of pipe is elevated relative to the second end. In the extended position, the pusher member is moved a selected distance away from the second end of the pipe receiving groove toward the first end of the pipe receiving groove so as to cause the second end of the joint of pipe to move through the pipe receiving groove towards the first end of the pipe receiving groove along a substantially horizontal plane and thereby cause the first end of the joint of pipe to be moved to a position overlying the rig floor.
Description




CROSS-REFERENCE TO RELATED APPLICATIONS




Not applicable.




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates generally to materials lifting apparatuses, and more particularly, but not by way of limitation, to an improved pipe handling apparatus for transporting pipe between a pipe storage rack and a rig floor which is elevated above the pipe storage rack.




2. Brief Description of the Related Art




In the drilling of a well, tubular members such as drill pipe, casing, and production tubing must be transported between a pipe storage rack and a drilling rig floor. For instance, it is necessary periodically to pull the drill string out of the well bore (“tripping out”) to replace the drill bit and in turn run the drill string back into the well bore. This process involves a series of repetitive steps in which joints of pipe are withdrawn from the well bore, disconnected, and stored on the pipe storage rack. The process is then repeated in reverse order to replace the drill string in the well bore. Due to the fact that the drilling rig floor can be as much as 20 to 30 feet above ground level, numerous devices have been previously proposed to assist in the movement of the tubular members between the pipe storage rack and the rig floor. Such devices are generally complex in construction, designed for use with a particular drilling rig, and not easily transported from one drilling rig to another.




As with the drilling process, the servicing of a well involves a series of repetitive steps to replace production tubing or maintenance downhole equipment. Rigs used for servicing wells are often referred to as “workover” rigs. Workover rigs generally have a rig floor positionable over the surface equipment of the well and a mast which supports the elevators. The elevators are used to raise and lower the production tubing into and out of the well bore and to handle the individual joints of pipe once they are on the rig floor.




The rig floor of a workover rig can be elevated as much as 6 to 15 feet above ground level depending on the amount of surface equipment utilized with the well. However, unlike with drilling rigs, it has been the practice to manually transport the pipe between the rig floor and the pipe rack. This involves a worker rolling a joint of pipe off the pipe rack onto a platform known as a “catwalk”. The worker then drags of the pipe toward the rig and raises one end of the pipe toward the rig floor to the point where the elevators of the rig can latch onto the end of the pipe. The process is reversed when removing pipe from the rig. This practice is extremely labor intensive, time consuming, and dangerous.




To this end, a need exists for an improved pipe handling apparatus which is simple in construction, easy to transport and operate, and which is adapted to be used with a variety of different rigs. It is to such an apparatus that the present invention is directed.




BRIEF SUMMARY OF THE INVENTION




The present invention is directed to a pipe handling apparatus for transporting a joint of pipe between a position adjacent a pipe storage rack and a rig floor elevated above the pipe storage rack. The pipe handling apparatus includes a support frame, a horizontally disposed platform, a carriage member, and a pusher member. The platform has a pipe receiving groove formed therein for receiving the joint of pipe. The pipe receiving groove has a first end and an opposing second end.




The carriage member is positioned near the first end of the pipe receiving groove and is connected to the support frame. The carriage member is movable from a lowered position wherein the joint of pipe which is positioned in the pipe receiving groove of the platform is supported in a substantially horizontal position and a raised position wherein the carriage member supports a first end of the joint of pipe at an elevated position relative to an opposed second end of the joint of pipe. The elevated position of the first end of the joint of pipe is at a height at least the height of the rig floor while the second end of the joint of pipe remains positioned in the pipe receiving groove.




The pusher member is in alignment with the pipe receiving groove so as to be engageable with the second end of the joint of pipe when the joint of pipe is positioned in the pipe receiving groove. The pusher member is movable along the pipe receiving groove between a retracted position and an extended position. In the retracted position, the pusher member is positioned near the second end of the pipe receiving groove to laterally support the joint of pipe when the first end of the joint of pipe is elevated relative to the second end. In the extended position, the pusher member is moved a selected distance away from the second end of the pipe receiving groove toward the first end of the pipe receiving groove so as to cause the second end of the joint of pipe to move through the pipe receiving groove towards the first end of the pipe receiving groove along a substantially horizontal plane and thereby cause the first end of the joint of pipe to be moved to a position overlying the rig floor.




The features and advantages of the present invention will become apparent from the following detailed description when read in conjunction with the accompanying drawings and appended claims.











BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS





FIG. 1

is a side elevational view of a pipe handling apparatus constructed in accordance with the present invention having a carriage member shown in a lowered position.





FIG. 2

is a side elevational view of the pipe handling apparatus of the present invention shown with the carriage member in a raised position.





FIG. 3

is an end elevational view of the pipe handling apparatus of the present invention shown positioned adjacent a pipe storage rack and aligned with the center of a floor of a workover rig.





FIG. 4

is an enlarged side elevational view of a portion of the pipe handling apparatus of the present invention shown with the carriage member in the raised position.





FIG. 5

is a side elevational view of a portion of the pipe handling apparatus of the present invention illustrating the raised end of the pipe moved to a position overlying the rig floor.





FIG. 6

is a perspective view of a first end of the platform and the carriage member shown in the lowered position.





FIG. 7

is a perspective view of a lower portion of the platform showing the carriage assembly in the lowered position.





FIG. 8

is a perspective view of a portion of the platform and a pusher assembly.





FIG. 9

is a cross sectional view taken along line


9





9


of FIG.


8


.





FIG. 10

is a cross sectional view taken along line


10





10


of

FIG. 8

showing an end view of the pusher assembly.





FIG. 11

is a side elevational view of the pusher assembly.





FIG. 12

is a perspective view of a jack assembly of the present invention.











DETAILED DESCRIPTION OF THE INVENTION




Referring now to the drawings and more particularly to

FIGS. 1-5

, a pipe handling apparatus


10


constructed in accordance with the present invention is shown. The pipe handling apparatus


10


adapted to be positioned adjacent a pipe storage rack


12


(

FIG. 3

) for facilitating the transport of a joint of pipe


14


between the pipe storage rack


12


and a rig floor


16


(

FIGS. 3 and 5

) which is typically elevated a distance above the pipe storage rack


12


. The pipe handling apparatus


10


includes a support frame


18


, a platform


20


, a carriage assembly


22


, a pusher assembly


24


, a pair of jack assemblies


26


, and a hydraulic assembly


28


.




The support frame


18


is an elongated rectangular structure having a first end


30


, a second end


32


, a first side


34


, a second side


36


, an upper side


38


, and a lower side


40


. The support frame


18


is constructed of a plurality of rigid tubular members interconnected to one in a suitable manner, such as by welding. The support frame


18


is provided with a stairway


42


to facilitate a worker's movement between the upper side


38


and the lower side


40


of the support frame


18


.




The platform


20


is secured to the upper side


38


of the support frame


18


so that the platform


20


is substantially horizontally disposed when the pipe handling apparatus


10


is in use. As best shown in

FIGS. 8-10

, the platform


20


is provided with a longitudinally extending pipe receiving groove


44


. As shown in

FIGS. 8 and 9

, the pipe receiving groove


44


is configured to hold the joint of pipe


14


to be transported to the rig floor


16


.




The pipe receiving groove


44


has a first end


46


(

FIG. 6

) and an opposing second end


48


(

FIG. 8

) and is formed by angling opposing portions


50


of the platform


20


in a downward direction (FIG.


9


). The platform


20


further includes an elongated slot


51


extending through the platform


20


and running the length of the pipe receiving groove


44


. The slot


44


is defined by the downwardly angled portions


50


of the platform


20


. As shown in

FIG. 6

, the platform


20


is provided with an elongated opening


52


in communication with the first end


46


of the pipe receiving groove


44


for receiving a portion of the carriage assembly


22


in a manner to be discussed below.




Returning to

FIGS. 1

,


2


and


8


, the platform further includes a hand rail


5


.


4


which is adapted to be positioned on either side of the platform


20


, and the platform includes a plurality of holes


56


on either side of the pipe receiving groove


44


for positioning a pair of stop members


58


(only one shown in

FIG. 8

) adjacent the pipe receiving groove


44


of the platform


20


for preventing the joint of pipe


14


from rolling through the pipe receiving groove


44


and across the platform


20


.




Referring now to

FIGS. 4-7

, the carriage assembly


22


includes a carriage member


60


and a cylinder


62


. The carriage member


60


is secured to the support frame


18


such that the carriage member


60


is positioned near the first end


46


of the pipe receiving groove


44


within the opening


52


of the platform


20


. The cylinder


62


functions to move the carriage member


60


from a lowered position (

FIGS. 1

,


6


, and


7


) wherein the joint of pipe


14


which is positioned in the pipe receiving groove


44


of the platform


20


is supported in a substantially horizontal position and a raised position (

FIGS. 2

,


4


, and


5


) wherein the carriage member


60


supports a first end


64


of the joint of pipe


14


at an elevated position relative to an opposing second end


66


of the joint of pipe


14


while the second end


66


of the joint of pipe


14


remains positioned in the pipe receiving groove


44


.




The carriage member


60


includes a V-shaped trough portion


68


which is positioned within the opening


52


of the platform


20


and configured to substantially correspond with the shape and size of the pipe receiving groove


44


such that the upper surface of the trough portion


68


functions as an extension of the pipe receiving groove


44


when the carriage member


60


is in the lowered position. The carriage member


60


further includes a bracket portion


70


extending from the lower side of the trough portion


680


.




As shown in

FIG. 5

, the trough portion


68


has a first end


72


and an opposing second end


74


. The bracket portion


70


has a proximal end


76


connected to the first end


72


of the trough portion


68


, a medial portion


78


pivotally connected to a pair of brackets


80


of the support frame


18


at a pivot point


82


located below the platform


20


, and a distal end


84


. The trough portion


68


is further supported in the lowered position by a pair of V-shaped support members


85


(

FIG. 7

) extending from the lower side of the platform.


20


in alignment with the opening


52


of the platform


20


. The second end


74


of the trough portion


68


of the carriage member


60


is provided with a pair or rollers


87


for rollingly supporting the first end


64


of the joint of pipe


14


in a manner to be discussed below.




The cylinder


62


has a first end


86


, a second end


88


, and a reciprocating rod


90


extending from the second end


88


of the cylinder


62


. The first end


86


of the cylinder


62


is pivotally secured to the support frame


18


below the platform


20


, and the distal end of the reciprocating rod


90


is pivotally connected to the distal end


84


of the bracket portion


70


of carriage member


60


, as shown in

FIGS. 4 and 5

.




Referring now to

FIGS. 1

,


2


,


8


,


10


, and


11


, the pusher assembly


24


includes a pusher member


92


and a cylinder


94


. The pusher member


92


is positioned in alignment with the pipe receiving groove


44


so as to be engageable with the second end


66


of the joint of pipe


14


when the joint of pipe


14


is positioned in the pipe receiving groove


44


. The cylinder


94


functions to move the pusher member


92


along the pipe receiving groove


44


between a retracted position and an extended position. In the retracted position, the pusher member


92


is positioned near the second end


48


of the pipe receiving groove


44


to laterally support the joint of pipe


14


when the first end


64


of the joint of pipe


14


is elevated relative to the second end


66


. In the extended position, the pusher member


92


is moved a selected distance away from the second end


48


of the pipe receiving groove


44


toward the first end


46


of the pipe receiving groove


44


so as to cause the second end


66


of the joint of pipe


14


to move through the pipe receiving groove


44


towards the first end


46


of the pipe receiving groove


44


along a substantially horizontal plane and thereby cause the first end


64


of the joint of pipe


14


to be moved to a position overlying the rig floor


16


(FIG.


5


).




The pusher member


92


includes a semi-circular shaped pipe engaging portion


96


positioned above the platform


20


and a bracket


98


extending from the pipe engaging portion


96


down through the slot


51


of the platform


20


. The pusher member


92


further includes a pair of rollers


100


for rollingly supporting the pusher member


92


on the platform


20


.




The cylinder


94


has a first end


102


, a second end


104


, and a reciprocating rod


106


extending from the second end


104


of the cylinder


94


. The cylinder


94


is secured to the support frame


18


below the platform


20


in a parallel relation to the pipe receiving groove


44


and the distal end of the reciprocating rod


106


is rigidly connected to a lower end of the bracket


98


of the pusher member


92


.




Referring now to

FIGS. 1

,


2


and


12


, each of the jack assemblies


26


is connected to the support frame


18


for selectively adjusting the height of the platform


20


relative to the height of the pipe storage rack


12


(FIG.


3


). Each of the jack assemblies


26


includes a hydraulic cylinder


108


with a foot


110


provided on the end of a reciprocating rod


112


of the cylinder


108


. The foot


110


is pivotally attached to the reciprocating rod


112


and includes a base member


114


and a pair of guide plates


116


extending upwardly therefrom. The foot


110


of the jack assemblies


26


swivels on the end of the reciprocating rod


112


and the guide plates


116


support the foot


110


between a pair of transverse support members


118


of the support frame


18


. The jack assemblies


26


permit the platform


20


to be raised and lowered as desired. The height of the platform


20


is adjusted so that the platform


20


is lower than the level of the pipe racks


12


when the joint of pipe


14


is being rolled onto the platform


20


and the platform


20


is positioned above the level of the pipe racks


12


when the joint of pipe


14


is being rolled from the platform


20


to the pipe racks


12


.




The cylinders


62


,


94


, and


108


can be any suitable cylinders known in the art, such as double-acting hydraulic cylinders. To this end, the hydraulic assembly


28


includes a hydraulic tank


119


, an engine


120


, and a control panel


122


which includes corresponding control valves for actuating each of the cylinders


62


,


94


. The cylinder


108


of jack assembly


26


is operated by a valve


124


mounted on the support frame


18


(FIG.


12


). A


20


horsepower engine with a 9 gallon per minute capacity has been found to be suitable. The control panel


122


is preferably portable whereby a workman can position the control panel


122


in a convenient and safe location at the work site. Because the use of operation of hydraulic circuits are well known in the art, as well as their various components, the hosing used in the present invention has been omitted from the drawings for the sake of clarity.




Operation




The pipe handling apparatus


10


can be transported to the work site by any suitable means, such as a low-bed trailer or truck (not shown). With the pipe handling apparatus


10


transported to the work site, the pipe handling apparatus


10


is unloaded and positioned adjacent the pipe storage rack


12


in a parallel relationship to the joints of pipe


14


on the pipe storage rack


12


and adjacent the rig floor


16


with the pipe receiving groove


44


of the platform


20


in a substantially perpendicular relationship thereto. The height of the pipe handling apparatus


10


may then be adjusted, if necessary, to position the platform


20


at a height level with or slightly below the height of the pipe storage rack


12


to permit the joints of pipe


14


on the pipe storage rack


12


to be easily transported onto the platform


26


and into the pipe receiving groove


44


merely by rolling the individual joints of pipe


14


. The height of the pipe handling apparatus


10


is adjusted by an operator actuating the cylinders


108


of the jack assemblies


26


so as to cause the reciprocating rods


112


and thus the foot


110


to be extended and thus raise the support frame


18


and the platform


20


. Suitably sized support or blocking members (not shown), such as timbers, may then be positioned under the lower side


40


of the support frame


18


. The reciprocating rods


112


of the jack assemblies


26


are then retracted so that the support frame


18


is supported on the support members. It will be appreciated that if the pipe handling apparatus


10


is being utilized to transport joints of pipe


14


from the rig floor


16


to the pipe storage rack


12


, it will be desirable to position the platform


20


at a height level with or slightly above the height of the pipe storage rack


12


to permit the joints of pipe


14


on the platform


20


to be easily transported onto the pipe storage rack


12


merely by rolling the individual joints of pipe


14


.




To transport a joint of pipe


14


from the pipe storage rack


12


to the rig floor


16


, the carriage member


60


is positioned in the lowered position and the pusher member


92


is positioned in the retracted position. An operator then rolls the joint of pipe


14


(as shown in

FIG. 3

) onto the platform


20


and into the pipe receiving groove


44


so that the first end


64


of the joint of pipe


14


is positioned in the trough portion


68


of the carriage member


60


(FIG.


6


). The operator then causes the cylinder


62


of the carriage assembly


22


to be actuated to extend the rod


90


and cause the carriage member


60


to be rotated about the pivot point


82


as represented by arrow


126


in

FIGS. 2 and 4

and thus the trough portion


68


of the carriage member


60


to move to the raised position (

FIGS. 2

,


4


, and


5


) whereby the first end


64


of the joint of pipe


14


is elevated to a height at least the height of the rig floor


16


while the second end


66


of the joint of pipe


14


remains positioned in the pipe receiving groove


44


.




The operator then causes the cylinder


94


of the pusher assembly


24


to be actuated to retract the rod


106


and cause the pusher member


92


to be moved along the pipe receiving groove


44


from the retracted position to the extended position, as represented by arrow


128


in

FIG. 2

, and thus cause the second end


66


of the joint of pipe


14


to move through the pipe receiving groove towards the first end


46


of the pipe receiving groove


44


along a substantially horizontal plane and thereby cause the first end


64


of the joint of pipe


14


to be moved to a position overlying the rig floor


16


(FIG.


5


). With the first end


64


of the joint of pipe


14


overlying the rig floor


16


, the carriage member


60


may be moved to the lowered position thereby lowering the first end


64


of the joint of pipe


14


onto the rig floor


16


where operators on the rig floor


16


can latch onto the first end


64


of the joint of pipe


14


with the elevators (not shown) of the rig and lift the joint of pipe


14


onto the rig floor


16


. The pusher member


92


is then returned to the retracted position to receive another joint of pipe


14


.




When the pipe handling apparatus


10


is employed to remove a joint of pipe


14


from the rig floor


16


, the first end


64


of the joint of pipe


14


is positioned on the carriage member


60


with the carriage member


60


in the raised position and the second end


66


of the joint of pipe


14


is positioned in engagement with the pusher member


92


with the pusher member


92


in the extended position. The pusher member


92


is then moved to the retracted position whereby the weight of the joint of pipe


14


causes the joint of pipe


14


to slide along the pipe receiving groove


44


and over the rollers


87


of the carriage member


60


toward the second end


48


of the pipe receiving groove


44


. The carriage member


60


is the moved to the lowered position and the joint of pipe


14


transferred to the pipe storage rack


12


.




From the above description it is clear that the present invention is well adapted to carry out the objects and to attain the advantages mentioned herein as well as those inherent in the invention. While presently preferred embodiments of the invention have been described for purposes of this disclosure, it will be understood that numerous changes may be made which will readily suggest themselves to those skilled in the art and which are accomplished within the spirit of the invention disclosed and as defined in the appended claims.



Claims
  • 1. A pipe handling apparatus for transporting a joint of pipe between a position adjacent a pipe storage rack and a rig floor elevated above the pipe storage rack, the joint of pipe having a first end and an opposing second end, the apparatus comprising:a support frame having a first end, a second end, a first side, a second side, an upper end, and a lower end; a platform secured to the upper end of the support frame such that the platform is fixed in a substantially horizontal position and extends continuously between the first and second sides of the support frame and the first and second ends of the support frame, the platform having a pipe receiving groove formed therein for receiving the joint of pipe, the pipe receiving groove having a first end and an opposing second end, the platform forming a substantially flat, continuous surface extending along each side of the pipe receiving groove from the first end of the platform to the second end of the platform so as to permit an individual to walk along the length of the pipe receiving groove on either side of the pipe receiving groove while the joint of pipe is being transported between the pipe storage rack and the rig floor; a carriage member positioned near the first end of the pipe receiving groove and connected to the support frame, the carriage member movable from a lowered position wherein the joint of pipe which is positioned in the pipe receiving groove of the platform is supported in a substantially horizontal position and a raised position wherein the carriage member supports the first end of the joint of pipe at an elevated position relative to the second end of the joint of pipe, the elevated position of the first end of the joint of pipe being at a height at least the height of the rig floor while the second end of the joint of pipe remains positioned in the pipe receiving groove; and a pusher member in alignment with the pipe receiving groove so as to be engageable with the second end of the joint of pipe when the joint of pipe is positioned in the pipe receiving groove, the pusher member movable along the pipe receiving groove between a retracted position and an extended position, in the retracted position the pusher member is positioned near the second end of the pipe receiving groove to laterally support the joint of pipe when the carriage member is in the raised position supporting the first end of the joint of pipe in an elevated position relative to the second end and in the extended position the pusher member is moved a selected distance away from the second end of the pipe receiving groove toward the first end of the pipe receiving groove so as to cause the second end of the joint of pipe to move through the pipe receiving groove towards the first end of the pipe receiving groove along a substantially horizontal plane when the carriage member is in the raised position supporting the first end of the joint of pipe in an elevated position relative to the second end of the joint of pipe and thereby cause the first end of the joint of pipe to be moved to a position overlying the rig floor.
  • 2. The pipe handling apparatus of claim 1 wherein the platform further has an elongated slot extending through the plate and in a parallel relationship with respect to the pipe receiving groove, wherein the pusher member includes a pipe engaging portion positioned above the platform and a bracket extending from the pipe engaging portion down through the slot, and wherein the pipe handling apparatus further comprises:a first cylinder having a first end, a second end, and a reciprocating rod extending from the second end of the cylinder, the first cylinder secured to the support frame below the platform in a parallel relation to the pipe receiving groove and the reciprocating rod connected to the bracket of the pusher member; and means for selectively actuating the rod of the first cylinder between a first position wherein the pusher member is positioned in the retracted position and a second position wherein the pusher member is positioned in the extended position.
  • 3. The pipe handling apparatus of claim 2 wherein the pipe engaging portion is rollingly supported on the platform.
  • 4. The pipe handling apparatus of claim 1 wherein the platform further has a carriage receiving opening in communication with the pipe receiving groove, wherein the carriage includes a trough portion positioned in the carriage receiving opening when the carriage is in the lowered position and a bracket portion, the trough portion having a first end and an opposing second end, the bracket portion having a proximal end connected to the first end of the trough portion, a medial portion pivotally connected to the support frame at a location below the platform, and a distal end, and wherein the pipe handling apparatus further comprises:a second cylinder having a first end, a second end, and a reciprocating rod extending from the second end of the cylinder, the second cylinder pivotally secured to the support frame below the platform and the reciprocating rod pivotally connected to the distal end of the bracket portion of carriage; and means for selectively actuating the rod of the second cylinder between a first position wherein the carriage is positioned in the lowered position and a second position wherein the carriage is rotated so as to cause the second end of the trough portion of the carriage to be moved to raised position.
  • 5. The pipe handling apparatus of claim 4 wherein the trough portion is substantially V-shaped.
  • 6. The pipe handling apparatus of claim 4 wherein the second end of the trough portion is provided with a pair of rollers for rollingly supporting the joint of pipe when the carriage is in the raised position and the pusher member is being moved from the retracted position to the extended position.
  • 7. The pipe handling apparatus of claim 1 further comprising:a plurality of jack assemblies connected to the support frame for selectively adjusting the height of the platform relative to the height of the pipe storage rack.
  • 8. The pipe handling apparatus of claim 1 wherein the platform further comprises a hand rail extending upwardly from at least one of the first and second sides of the platform.
  • 9. The pipe handling apparatus of claim 1 wherein the platform further has a plurality of holes adjacent the pipe receiving groove on each side of the pipe receiving groove, and wherein the pipe handling apparatus further comprises:a plurality of stop members positioned in the holes of the platform on the side of the pipe receiving groove opposite the pipe storage rack and extending upwardly from the platform to prevent the joint of pipe from rolling through the pipe receiving groove.
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