Maneuverable wellbore tubular makeup and breakout apparatus and method

Information

  • Patent Grant
  • 6431029
  • Patent Number
    6,431,029
  • Date Filed
    Friday, February 2, 2001
    24 years ago
  • Date Issued
    Tuesday, August 13, 2002
    23 years ago
Abstract
A maneuverable powerjaw apparatus for making and breaking joints of well bore tubular is provided for operation on a rig floor. Preferably a plurality of wheels are mounted to a mobile housing in a reverse tricycle orientation that permits high maneuverability of the mobile housing including rotation in position. Preferably, the two forward wheels are individually powered by hydraulic motors. Vertical orientation of the mobile housing is preferably provided by hydraulic struts that, once the mobile housing is positioned adjacent the pipes on the rig floor, permit the power jaws to be positioned at the correct vertical position on the joints for making, breaking, and spinning of the pipes. In one presently preferred embodiment, a pivotal connection is provided between the mobile housing and a frame to which torque arms are attached. In this embodiment, the frame rotates with respect to the well bore tubular as the joints are made or broken while the mobile housing may remain stationary.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates generally to making up and breaking out well bore tubular and, more particularly, to apparatus and methods for a makeup and break out tool that is readily maneuverable in a rig floor environment.




2. Description of the Background




Makeup and break out tools are used to spin, makeup, and break out well bore tubular that may have a wide range of diameters. It has been found by oil companies that separate, manually operated tongs, spinners, and/or chains are often significantly slower in making up and breaking out well bore tubular than a single tool or unit that does all such functions. The speed advantages of a single unit include factors such as eliminating the need to redress tongs when changing from drill pipe to collars and the integration of spinning with makeup and break out functions. Due to the high daily cost of drilling rigs, the time savings can be substantial. Comparison studies between use of traditional separate tongs and spinners as compared with a single unit makeup and break out tool have shown cost savings that may range from one-quarter of a million to more than a million dollars per well. Another time saving advantage is that a self-contained unit can be used to make up or break out pipes at difficult positions in the rig or derrick - a feature that can save a great amount of time especially in certain situations that occasionally occur, e.g., stuck pipe. Furthermore, when desired, pipes can be readily made up or broken out while in the mousehole with the rig otherwise occupied. An exemplary self-contained unit for making and breaking joints in pipe strings is shown in U.S. Pat. No. 5,868,045 and U.S. Pat. No. 5,386,746 which are incorporated herein by reference.




The self-contained system operates more reliably than separate tongs and spinners by providing a central torque regulator that connects to and controls all components to assure consistent makeup. This feature prevents thread damage caused by over tightening and automatically prevents errors that could result in under-torqued connections.




The system eliminates accident conditions associated with separate independent tongs readily exposed on the floor, and the attendant separate cables used to pull on each separate tong, and use of snatch blocks. Safety is also improved because providing a single tool to perform all such functions rather than separate elements permits the use of central safety features such as, for instance, a lockout to prevent spinner operation if the tongs are not engaged, a safe location for the operator to stand and work, a design whereby the operator's hands and feet are safely away from moving parts, elimination of spinning chains, and a lockout to prevent operation of the lift cylinder when any tong is engaged.




Because of the great utility of a self-contained unit to makeup and break out pipes, it has been found desirable to make further improvements. For instance, a support line is normally secured to the top of the unit to support the unit and permit mobility of the unit. Even though the unit actually requires only one line as compared to at least two support lines used to support separate tongs as well as pull lines for pulling on each separate tong, it would nonetheless be desirable to eliminate the support line on some rigs due to limited line availability. Moreover, because a self-contained unit will necessarily have considerable weight, effort is required, usually involving two people, to initially pull the makeup and break out unit to the desired connection. While even these factors are at least on a par or typically better than use of separate tongs and spinners which require at least two support lines and two pull lines and at least two or three people to operate the tongs and pull lines, nonetheless it would be desirable to control a makeup and break out unit with a single operator using automated controls without the need for any lines.




One commercially available system uses two straight tracks wherein motored wheels move the make-up and break-out tool forward and backward. However, this configuration uses rig floor space at all times, may not be used elsewhere on the rig floor, is very limited in operational positioning, and may be difficult to adapt to many rig floor arrangements.




Consequently, there remains a need for a self-contained makeup and break out unit that permits a single operator to perform the function of making and breaking the joints of well bore tubular. It would also be desirable to eliminate the requirement for a support line. However, it would be desirable to maintain the ability to use a line to permit the unit to be used in odd locations when desired and/or for transport purposes. Those skilled in the art have long sought and will appreciate the present invention which provides solutions to these and other problems.




SUMMARY OF THE INVENTION




The present invention was designed to provide more efficient operation to thereby reduce drilling costs, improve reliability of making and breaking pipe joints, permit increased automation to reduce required manpower, improve safety, and to free other rig equipment for other uses.




Therefore, it is an object of the present invention to provide an improved self-contained unit for making and breaking well bore tubular.




Another object of the present invention is to automate most of the functions of making and breaking of pipe joints for more efficient operation.




Yet another object of the present invention is to provide a means for powered 3-dimensional movement of a self-contained pipe making and breaking unit.




Yet another object of the present invention is to free up equipment on a rig such as support lines.




An advantage of the present invention is improved rig safety.




Another advantage of the present invention is faster operation.




Yet another advantage is improved reliability and consistency in making up joints.




These and other objects, features, and advantages of the present invention will become apparent from the drawings, the descriptions given herein, and the appended claims.




Therefore, the present invention provides for a maneuverable powerjaw apparatus for making and breaking joints of well bore tubular which comprises at least two powered torque arms for applying torque to the joints of the well bore tubular. A support member supports the powered torque arms. A mobile frame supports the support member and the two powered torque arms. The support member is preferably movable with respect to the mobile frame. One or more hydraulically movable members are mounted between the support member and the mobile frame. One or more wheels are mounted to the mobile frame.




A first wheel and a second wheel are mounted to the mobile frame with a fixed orientation. A first hydraulic control motor may be used to activate the first wheel, and a second hydraulic control motor may be used to activate the second wheel. Preferably, the two wheels are mounted to the mobile frame such that a straight line passes through each of the two wheels and a respective of the well bore tubular when the at least two power torque arms apply the torque.




In other words, a maneuverable power jaw apparatus is provided for making and breaking joints of well bore tubular such that the maneuverable power jaw apparatus may be operable on a rig floor. A mobile frame supports a support member to which at least two powered torque arms are attached. At least three wheels are mounted to the mobile frame to permit movement of the mobile frame on the rig floor. At least one movable member is mounted to the mobile frame and the support member for affecting movement between the mobile frame and the support member. Preferably the movable member comprises a hydraulic rod for vertically moving the support member with respect to the mobile frame.




In operation, a method is provided for a power jaw apparatus for making and breaking joints of well bore tubular which includes mounting the power torque arms in a housing and steering the housing in a left-hand direction or right-hand direction on the rig floor. Preferably, steering is accomplished by activating a hydraulic motor. Moreover, by controlling power applied to two wheels with a fixed orientation steering may be affected because the wheels are preferably positioned in a reverse tricycle orientation. At least one wheel, at the rear of the housing, has a rotatable orientation and follows movement controlled by the two front wheels. The powered torque arms are preferably hydraulically lifted for vertical engagement with a respective of the joints. Preferably wheel guards are provided on the housing around the plurality of wheels.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of a self-contained makeup and break out unit suspended on a support cable as used in the prior art;





FIG. 2

is a perspective view of a mobility component for a self-contained makeup and break out unit in accord with the present invention;





FIG. 3

is a lower plan view, partially in section, of the mobility component of

FIG. 2

;





FIG. 4

is a partial elevational view, partially in section of the mobility component of

FIG. 2

;





FIG. 5

is an elevational view, partially in section, of an embodiment of the present invention with a swivel section;





FIG. 6

is a top view, partially in section, of the swivel section of

FIG. 5

in a first position; and





FIG. 7

is a top view, partially in section, of the swivel section of

FIG. 5

in a second rotated position as compared to FIG.


7


.




While the present invention will be described in connection with presently preferred embodiments, it will be understood that it is not intended to limit the invention to those embodiments. On the contrary, it is intended to cover all alternatives, modifications, and equivalents included within the spirit of the invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Referring now to the drawings, and more particularly to

FIG. 1

, which shows components


18


,


20


, and


22


, which may be referred to generally as tongs, wrenches, torque arms, jaws, or the like. Torque arms


18


,


20


, and


22


are secured together in a vertical orientation within self-contained unit


10


for making and breaking joints


12


of tubular


14


and


16


. While tubular


14


and


16


are normally substantially vertically oriented, unit


10


and/or other means discussed subsequently will preferably include a tilt mechanism whereby tubular, such as those offset somewhat from the vertical, may be engaged by torque arms


18


,


20


, and


22


. For instance, tubular positioned in the mousehole may be offset from the vertical and unit


10


may still be used to make and break connections of such tubular. A prior art connection


24


to support line


26


is shown as has been used in the prior art. The present invention makes support line


26


optional.





FIG. 2

shows support elements of mobility unit


50


in accord with the present invention. Mobile unit


50


, as shown in

FIGS. 2-4

, preferably provides for individually powered front wheels


52


and


54


to move mobile unit


50


on rig floor


51


(See FIG.


4


). Rig floor


51


includes the operation floor of any type of rig such as drilling rigs and work over rigs, offshore rigs, drill ships, and any other type of well bore drilling or work over operation which has a suitable floor for movement by means of wheels such as wheels


52


and


54


.




Wheels


52


and


54


are preferably mounted in a fixed orientation but are separately controllable by one or more hydraulic motors to make mobile unit


50


highly maneuverable on rig floor


51


. The hydraulic controls are discussed briefly in connection with FIG.


3


. Follower wheel(s)


56


provides support of the rear of mobile unit


50


on swivel mount


55


. Front wheels


52


and


54


provide controllable movement of self-contained unit


10


for placing unit


10


in position for working with the pipe. During the making and breaking operation, unit


10


will typically move circularly typically less than one-quarter turn during final makeup or initial break out as relatively high torque is applied. The rotation is around the drill pipe because the drill pipe is fixed in position with respect to horizontal movement. Therefore front wheels


52


and


54


may be preferably positioned such that rotation is easily permitted. For instance, front wheels


52


and


54


may be positioned substantially in line with pipe


30


as shown in

FIG. 3

such that a straight line can be drawn between front wheels


52


and


54


and pipe


30


when the torque arms are gripping the pipe. With this wheel positioning, rotational movement of unit


10


is easily followed by front wheels


52


and


54


. Moreover, front wheels


52


and


54


may be in a neutral position such that they can roll easily or perhaps roll with damped movement during the makeup and break out rotation. A control may be provided such that wheels


52


and


54


are substantially in a neutral position when two torque wrenches are engaged. The preferred positioning of the wheels permits mobile unit


50


to be highly maneuverable and in fact mobile unit


50


can rotate in position when the wheels are positioned as shown although other wheel positions could be selected as desired.




Rear wheel


56


is preferably a follower wheel that is swivel mounted to follow movement of wheels


52


and


54


. Rear wheel


56


preferably includes one swivel mounted wheel or two swivel mounted wheels


56


as shown to provide additional support. Base


57


is sized to provide an adequate footprint for wheels


52


,


54


, and


56


to sturdily support unit


10


while being small enough to be maneuverable on the rig floor. Preferably base


57


includes wheel guards


59


,


61


, and


63


to protect from feet inadvertently placed in the path of the wheels. The wheel guards


59


,


61


, and


63


may include relatively soft rubber bumper portions if desired. Because mobile unit


50


moves relatively slowly, should a person inadvertently position a foot in the wheels path, the wheel guards would not injure a person upon contact but would give ample notification to permit movement of the person's feet. The operator's position is selected to be away from moving components, preferably in the front of mobile unit


50


. However, it would be possible to provide a control unit adjacent the driller's position whereby a single driller could perform most functions associated with making and breaking the pipes. While a reverse tricycle wheel orientation of the plurality is preferred, other wheel arrangements and numbers of wheels could be used. By reverse tricycle wheel orientation is meant two wheels or two groups of wheels in the front of mobile unit


50


(the side with power arms) and one wheel or group of wheels in the rear. The two front wheels are fixed in position but can be steered in a highly maneuverable manner by individual application of power. The rear wheel is preferably a follower wheel and preferably swivels to follow movement. However, the design could provide that the rear wheel is powered for movement and rotation while the two front wheels are followers. While the reverse tricycle wheel orientation is one wheel orientation that permits rotation in place as well as movement of mobile unit


50


, other wheel orientations that provide the same or similar functions could be used.




Hydraulic supports


58


,


60


, and


62


provide hydraulic means for vertically positioning unit


10


with respect to joint


12


. In this way, the particular tongs or wrenches


18


,


20


, and


22


can be positioned at the desired positions. Preferably vertically oriented hydraulic cylinders


58


,


60


, and


62


drive respective hydraulic rods


64


,


66


, and


68


that is mount lift frame or support member


70


. Lift frame or support member


70


provides members such as side members


72


and


74


and bottom member


76


for connection to unit


10


. Preferably unit


10


is vertically movable with respect to cylinders or supports


58


,


60


, and


62


. Additional support elements


78


and


80


may also be used for connection to unit


10


as desired. It will be understood that lift frame


70


is shown in a conceptual form and that various modifications may be made for a secure connection with respect to unit


10


as desired. Lift frame


70


may be provided as a readily removeable add on component or may be built into the design of unit


10


as desired. Supports


58


,


60


, and


62


may be pivotally mounted, if desired, to permit tilting of unit


10


. While vertically or substantially vertically oriented hydraulic supports are preferred, other mechanical arrangements could conceivably be used such as rotating screws for lifting, folding or expanding frames, and the like whereby either hydraulic forced is applied differently or other means of power such as air or explosion proof electric power devices are used.




Support line connector


82


is provided so that unit


10


may be lifted by support line either during transport or for operation within the rig. For instance, one use of a combined unit


10


allows the positioning at places in the rig which may be elevated with respect to the rig floor to break connections that are well off the rig floor as may occur due to stuck pipe and the like.




FIG.


3


and

FIG. 4

show hydraulic motors


84


and


86


used to operate front wheels


52


and


54


as well as various hydraulic lines. Also shown are hydraulic lines such as hydraulic lines used to operate the hydraulic lift rods, such as hydraulic lift rods


64


,


66


, and


68


. The hydraulic controls permit a single operator to move self-contained unit


10


to engage pipe


30


, and perform the necessary functions. The hydraulic operation eliminates the need for support lines and the unit can be easily moved out of the way when desired. While a preferred embodiment of the invention utilizes hydraulic power, air motors and air lifts may also be used if desired. If desired, it may be possible to use electrical equipment for operation on the rig floor if explosion proof electrical construction is utilized.




In operation, hydraulically controlled wheels


52


and


54


can be used to move unit


10


to engage the pipe joint. Follower wheel(s)


56


follow guidance of controlled wheels


52


and


54


. After unit


10


is positioned adjacently the pipe, hydraulic rods


64


,


66


, and


68


move lift frame


70


up and down as necessary to properly position torque arms


18


,


20


, and


22


with respect to the pipe joint. If the pipe is to be broken, then two torque arms break the connection. During the breaking of the pipe, unit


10


will rotate a few degrees around the pipe. Wheels


52


and


54


are positioned to facilitate such movement and may be in neutral or a damped neutral position that allows such rotation. A spinner unit (not shown) then spins the pipe until the pipe is ready to be separated. As the removed pipe or group of pipes is being positioned, unit


10


may be moved out of the way so that the blocks can pull the next joint to be broken into position above the rig floor. Making up of the pipe proceeds substantially the same in the opposite order.





FIG. 5

,

FIG. 6

, and

FIG. 7

show another embodiment of the present invention which incorporates swivel stand


100


into mobility unit


50


. Due to rotation that is induced by unit


10


as pipes


14


and


16


are broken or tightened, for some drilling rig floor arrangements it may be desirable that wheels


52


,


54


, and


56


do not rotate during tightening or loosening as discussed above. However, unit


10


must still rotate. Therefore swivel stand


100


is incorporated into mobility unit


50


to permit unit


10


to rotate while wheels


52


,


54


, and


56


as well as wheel guards


59


,


61


, and


63


remain stationary or substantially stationary. Swivel stand


100


may built into mobility unit


50


at a desired position therein. For instance, swivel stand


100


may, but not necessarily, can be positioned below supports


78


and


80


which support unit


10


and which may preferably rotate therewith. Swivel stand


100


will be positioned at some position above wheels


52


,


54


, and


56


. Thus in one embodiment, lower swivel plate


102


may be positioned on mobility unit


50


above or adjacent wheel guards


59


,


61


, and


63


as indicated in FIG.


5


. Upper swivel plate


104


will then support unit


10


and will swivel or rotate with respect to lower swivel plate


102


. In this way, wheels


52


,


54


, and


56


may remain substantially stationary as unit


10


rotates as joints of pipe are connected or disconnected.




In one presently preferred embodiment, multiple swivel support wheels may be used between lower swivel plate


102


and upper swivel plate


104


to provide for relative rotation. For instance, a primary track


105


may be provided in which a plurality of primary wheels


108


are positioned. To maintain balance of the weight of unit


10


over primary wheels


108


, a secondary track


106


may be provided with secondary wheels


110


. In a present embodiment, the wheels are mounted by bolts and nuts such as bolt/nut arrangements


112


for secondary wheels


110


and bolt/nut arrangements


114


for primary wheels


108


. To provide additional balance and support of the weight of unit


10


over primary wheels


108


, outer lateral wheels


116


may be used that travel along surface or wall


120


. Outer lateral wheels


116


and wall


120


may be oriented perpendicular or transversely with respect to primary wheels


108


and track


105


. Bolt/nut arrangement


118


may be used to mount outer lateral wheels


116


. Supports


122


and


124


may be used to support outer lateral wheels


116


and move with lateral wheels


116


during rotation. Inner lateral wheels


117


may also be used and travel along inner wall


119


.




Secondary support or wall


126


moves with secondary wheels


110


as secondary wheels


110


are mounted onto support or secondary wall


126


by means of bolt/nut arrangements


112


. Securing block


128


is mounted to lower swivel plate


102


and secures track support


130


which contains track


106


to lower swivel plate


102


. Support or wall


132


provides mounting for primary wheels


108


and moves with primary wheels


108


. Other wheel arrangements and means could be provided to permit relative rotation between lower swivel plate


102


and upper swivel plate


104


.





FIG. 7

shows swivel stand


100


in a rotated position. Thus, secondary wheels


110


, as well as the primary wheels and other wheels discussed herein before have been rotated along their respective tracks, such as track


106


, track


105


, surface


120


, and the like.

FIG. 7

also shows various components of unit


10


to indicate how the various components relate together. Cylinder


134


and cylinder push rod


136


or other means may preferably be used to return unit


10


to the first position shown in FIG.


5


and

FIG. 6

from the second or rotated position as indicated in FIG.


7


. For this purpose, cylinder push rod


136


may be secured through various frame interconnections so as to be affixed with respect to lower swivel plate


102


. On the other hand, cylinder


134


is secured to upper swivel plate


104


. Thus, cylinder


134


and cylinder push rod


136


may be used to control rotation between lower swivel plate


102


and upper swivel plate


104


such as by returning the relative position from the second or rotated position of

FIG. 7

to the first or unrotated position shown by FIG.


5


and FIG.


6


. Cylinder


134


may be hydraulically or pneumatically operated.




The present invention is adaptable to other type of movement control. For instance, instead of hydraulically operated wheels, a telescoping boom could be used to move mobility unit


50


wherein wheels may or may not be hydraulically operated, as desired.




The foregoing disclosure and description of the invention is illustrative and explanatory thereof, and it will be appreciated by those skilled in the art, that various changes in the size, shape and materials, the use of mechanical equivalents, as well as in the details of the illustrated construction or combinations of features of the various coring elements may be made without departing from the spirit of the invention.



Claims
  • 1. A maneuverable power jaw apparatus for making and breaking joints of well bore tubular, comprising:at least two powered torque arms for applying torque to said joints of said well bore tubulars; a support frame for supporting said at least two powered torque arms; a mobile frame for supporting said support frame and said at least two powered torque arms, said support frame being movable with respect to said mobile frame; one or more hydraulically movable members mounted between said support frame and said mobile frame; a swivel stand for supporting the mobile frame and to permit rotational movement of the mobile frame with respect to the rig floor; and at least three wheels mounted to the swivel stand to permit movement of the apparatus on a rig floor.
  • 2. The maneuverable power jaw apparatus of claim 1, wherein said wheels comprise:a first wheel mounted to said mobile frame with a fixed orientation, and a second wheel mounted to said mobile frame with a fixed orientation.
  • 3. The maneuverable power jaw apparatus of claim 2, further comprising:a first hydraulic control for said first wheel, and a second hydraulic control for said second wheel.
  • 4. The maneuverable power jaw apparatus of claim 2, further comprising:a third wheel mounted to said mobile frame.
  • 5. The maneuverable power jaw apparatus of claim 4, wherein said third wheel is swivel mounted with respect to said mobile frame.
  • 6. The maneuverable power jaw apparatus of claim 1, wherein said wheels comprise at least one swivel mounted wheel.
  • 7. The maneuverable power jaw apparatus of claim 1, wherein said wheels comprises at least two swivel mounted wheels.
  • 8. The maneuverable power jaw apparatus of claim 1, wherein said wheels comprise at least two wheels, said two wheels being mounted to said mobile frame such that a straight line passes through each of said two wheels and a respective of said well bore tubular when said at least two power torque arms apply said torque.
  • 9. The maneuverable power jaw apparatus of claim 1, wherein said wheels comprises at least three swivel mounted wheels.
  • 10. A maneuverable power jaw apparatus for making and breaking joints of well bore tubular, said maneuverable power jaw apparatus being operable on a rig floor, comprising:at least two powered torque arms for applying torque to said joints of said well bore tubulars; a mobile frame for supporting said at least two powered torque arms; a swivel stand for supporting the mobile frame and to permit rotational movement of the mobile frame with respect to the rig floor; and at least three wheels mounted to said swivel stand to permit movement of said apparatus on said rig floor.
  • 11. The maneuverable powerjaw apparatus of claim 10, wherein at least one of said at least three wheels is swivel mounted to said mobile frame.
  • 12. The maneuverable power jaw apparatus of claim 10, further comprising:a first hydraulic motor for a first of said at least three wheels.
  • 13. The maneuverable power jaw apparatus of claim 12, further comprising:a second hydraulic motor for a second of said at least three wheels.
  • 14. The maneuverable power jaw apparatus of claim 10, further comprising:a support member for supporting said at least two powered torque arms, said mobile frame supporting said support member such that said support member and said at least two powered torque arms are movable with respect to said mobile frame, and at least one movable member mounted to said mobile frame and said support member for affecting movement between said mobile frame and said support member.
  • 15. The maneuverable powerjaw apparatus of claim 14, wherein said at least one movable member comprises a hydraulic rod.
  • 16. The maneuverable power jaw apparatus of claim 14, wherein said support member is vertically movable with respect to said mobile frame.
  • 17. A maneuverable power jaw apparatus for making and breaking joints of well bore tubular, comprising:at least two powered torque arms for applying torque to said joints of said well bore tubulars; a support frame for supporting said at least two powered torque arms; a mobile frame for supporting said support frame and said at least two powered torque arms; a pivotal connection between said support frame and said mobile frame such that said support frame is pivotal with respect to said mobile frame; a swivel stand for supporting the mobile frame and to permit rotational movement of the mobile frame with respect to the rig floor; and at least three wheels mounted to said swivel stand to permit movement of the mobile frame on a rig floor.
  • 18. The maneuverable power jaw of claim 17, wherein said one or more wheels comprise:a first wheel mounted to said mobile frame with a fixed orientation, and a second wheel mounted to said mobile frame with a fixed orientation.
  • 19. The maneuverable power jaw apparatus of claim 17, wherein said pivot connection further comprises:one or more tracks affixed to said mobile frame, and a plurality of wheels moveably in said one or more tracks.
  • 20. The maneuverable power jaw apparatus of claim 17, further comprising:a cylinder connected between said mobile frame and said support frame, said cylinder being activated for pivoting said support frame with respect to said mobile frame.
  • 21. The maneuverable power jaw apparatus of claim 17, wherein said wheels comprises at least three swivel mounted wheels.
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