Method of landing items at a well location

Information

  • Patent Grant
  • 6644413
  • Patent Number
    6,644,413
  • Date Filed
    Wednesday, January 23, 2002
    23 years ago
  • Date Issued
    Tuesday, November 11, 2003
    21 years ago
Abstract
A method of lowering items from a drilling rig to a well located below it through the use of a landing string comprised of drill pipe having an enlarged diameter section with a shoulder, in combination with upper and lower holders having wedge members with shoulders that engage and support the drill pipe at the shoulder of the enlarged diameter section. The shoulder of the drill pipe and the shoulders of the wedge members are rotatable with respect to each other.
Description




STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT




Not applicable




REFERENCE TO A “MICROFICHE APPENDIX”




Not applicable




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a method of lowering items from a drilling rig to a well located below the rig for use in the oil and gas well drilling industry. More particularly, the present invention relates to a method of lowering items from a drilling rig through the use of a landing string comprised of drill pipe having an enlarged diameter section with a shoulder, in combination with upper and lower holders having wedge members with shoulders that engage and support the drill pipe at the shoulder of the enlarged diameter section.




2. General Background




Oil and gas well drilling and production operations involve the use of generally cylindrical tubes commonly known in the industry as “casing” which line the generally cylindrical wall of the borehole which has been drilled in the earth. Casing is typically comprised of steel pipe in lengths of approximately 40 feet, each such length being commonly referred to as a “joint” of casing. In use, joints of casing are attached end-to-end to create a continuous conduit. In a completed well, the casing generally extends the entire length of the borehole and protects the production tubing that conducts oil and gas from the producing formation to the top of the borehole, where one or more blowout preventors or production trees may be located on the sea floor.




Casing is generally installed or “run” into the borehole in phases as the borehole is being drilled. The casing in the uppermost portion of the borehole, commonly referred to as “surface casing,” may be several hundred to several thousand feet in length, depending upon numerous factors including the nature of the earthen formation being drilled and the desired final depth of the borehole.




After the surface casing is cemented into position in the borehole, further drilling operations are conducted through the interior of surface casing as the borehole is drilled deeper and deeper. When the borehole reaches a certain depth below the level of the surface casing, depending again on a number of factors such as the nature of the formation and the desired final depth of the borehole, drilling operations are temporarily halted so that the next phase of casing installation, commonly known as intermediate casing, may take place.




Intermediate casing, which may be thousands of feet in total length, is typically made of “joints” of steel pipe, each joint typically being in the range of about 38 to 42 feet in length. The joints of intermediate casing are attached end-to-end, typically through the use of threaded male and female connectors located at the respective ends of each joint of casing.




In the process of installing the intermediate casing, joints of intermediate casing are lowered longitudinally through the floor of the drilling rig. The length of the column of intermediate casing grows as successive joints of casing are added, generally one to four at a time, by drill hands and/or automated handling equipment located on the floor of the drilling rig.




When the last intermediate casing joint has been added, the entire column of intermediate casing, commonly referred to as the intermediate “casing string”, must be lowered further into its proper place in the borehole. The task of lowering the casing string into its final position in the borehole is accomplished by adding joints of drill pipe to the top of the casing string. The additional joints of drill pipe are added, end-to-end, by personnel and/or automated handling equipment located on the drilling rig, thereby creating a column of drill pipe known as the “landing string.” With the addition of each successive joint of drill pipe to the landing string, the casing string is lowered further and further.




During this process as practiced in the prior art, when an additional joint of drill pipe is being added to the landing string, the landing string and casing string hang from the floor of the drilling rig, suspended there by a holder or gripping device commonly referred to in the prior art as “slips.” When in use, the slips generally surround an opening in the rig floor through which the upper end of the uppermost joint of drill pipe protrudes, holding it there a few feet above the surface of the rig floor so that rig personnel and/or automated handling equipment can attach the next joint(s) of drill pipe.




The inner surface of the prior art slips has teeth-like grippers and is curved such that it corresponds with the outer surface of the drill pipe. The outer surface of prior art slips is tapered such that it corresponds with the tapered inner or “bowl” face of the master bushing in which the slips sit.




When in use, the inside surface of the prior art slips is pressed against and “grips” the outer surface of the drill pipe which is surrounded by the slips. The tapered outer surface of the slips, in combination with the corresponding tapered inner face of the master bushing in which the slips sit, cause the slips to tighten around the gripped drill pipe such that the greater the load being carried by that gripped drill pipe, the greater the gripping force of the slips being applied around that gripped drill pipe. Accordingly, the weight of the casing string, and the weight of the landing string being used to “run” or “land” the casing string into the borehole, affects the gripping force being applied by the slips, i.e., the greater the weight the greater the gripping force and crushing effect.




As the world's supply of easy-to-reach oil and gas formations is being depleted, a significant amount of oil and gas exploration has shifted to more challenging and difficult-to-reach locations such as deep-water drilling sites located in thousands of feet of water. In some of the deepest undersea wells drilled to date, wells may be drilled from a rig situated on the ocean surface some 5,000 to 10,000 feet above the sea floor, and such wells may be drilled some 15,000 to 20,000 feet below the sea floor. It is envisioned that as time goes on, oil and gas exploration will involve the drilling of even deeper holes in even deeper water.




For many reasons, including the nature of the geological formations in which unusually deep drilling takes place and is expected to take place in the future, the casing strings required for such wells must be unusually long and must have unusually thick walls, which means that such casing strings are unusually heavy and can be expected in the future to be even heavier. Moreover, the landing string needed to land the casing strings in such extremely deep wells must be unusually long and strong, hence unusually heavy in comparison to landing strings required in more typical wells.




For example, a typical well drilled in an offshore location today may be located in about 300 to 2000 feet of water, and may be drilled 15,000 to 20,000 feet into the sea floor. Typical casing for such a typical well may involve landing a casing string between 15,000 to 20,000 feet in length, weighing 40 to 60 pounds per linear foot, resulting in a typical casing string having a total weight of between 600,000 to 1,200,000 pounds. The landing string required to land such a typical casing string may be 300 to 2000 feet long which, at about 35 pounds per linear foot of landing string, results in a total landing string weight of 10,500 to 70,000 pounds. Hence, prior art slips in typical wells have typically supported combined landing string and casing string weight in the range of between about 610,500 to 1,270,000 pounds.




By way of contrast, extremely deep undersea wells located in 5,000 to 10,000 feet of water, uncommon today but expected to be more common in the future, may involve landing a casing string 15,000 to 20,000 feet in length, weighing 40 to 80 pounds per linear foot, resulting in a total casing string weight of 600,000 to 1,600,000 pounds. The landing string required to land such casing strings in such extremely deep wells may be 5,000 to 10,000 feet long which, at 70 pounds per linear foot, results in a total landing string weight of about 350,000 to 700,000 pounds. Hence, the combined landing string and casing string weight for extremely deep undersea wells may be in the range of 950,000 to 2,300,000 pounds, instead of the 610,500 to 1,270,000 pound range generally applicable to more typical wells. In the future, as deeper wells are drilled in deeper water, the combined landing string and casing string weight can be expected to increase, perhaps up to as much as 4,000,000 pounds or more.




Under certain circumstances, prior art slips have been able to support the combined landing string and casing string weight of 610,500 to 1,270,000 pounds associated with typical wells, depending upon the size, weight and grade of the pipe being held by the slips. In contrast, prior art slips cannot effectively and consistently support the combined landing string and casing string weight of 950,000 to 2,300,000 pounds associated with extremely deep wells, because of numerous problems which occur at such extremely heavy weights.




For example, prior art slips used to support combined landing string and casing string weight above the range of about 610,500 to 1,270,000 pounds have been known to apply such tremendous gripping force that (a) the gripped pipe has been crushed or otherwise deformed and thereby rendered defective, (b) the gripped pipe has been excessively scored and thereby damaged due to the teeth-like grippers on the inside surface of the prior art slips being pressed too deeply into the gripped drill pipe and/or (c) the prior art slips have experienced damage rendering them inoperable.




A related problem involves the uneven distribution of force applied by the prior art slips to the gripped pipe joint. If the tapered outer wall of the slips is not substantially parallel to and aligned with the tapered inner wall of the master bushing, that can create a situation where the gripping force of the slips in concentrated in a relatively small portion of the inside wall of the slips rather than being evenly distributed throughout the entire inside wall of the slips. Such concentration of gripping force in such a relatively small portion of the inner wall of the slips can (a) crush or otherwise deform the gripped drill pipe, (b) result in excessive and harmful strain or elongation of the drill pipe below the point where it is gripped and (c) cause damage to the slips rendering them inoperable.




This uneven distribution of gripping force is not an uncommon problem, as the rough and tumble nature of oil and gas well drilling operations cause the slips and/or master bushing to be knocked about, resulting in misalignment and/or irregularities in the tapered interface between the slips and the master bushing. This problem is exacerbated as the weight supported by the slips is increased, which is the case for extremely deep wells as discussed above.




BRIEF SUMMARY OF THE INVENTION




The present invention does away with the use of prior art slips and provides for the use of upper and lower holders which support the drill pipe without crushing, deforming, scoring or causing elongation of the drill pipe being held. The present invention includes the use of wedge members which can be raised out of and lowered into the holders.




The present invention provides for the use of the holders in combination with an enlarged diameter section of the drill pipe which is spaced apart from the ends of the drill pipe.




The enlarged diameter section has a shoulder which corresponds to a shoulder on the movable wedge members of the holders. The engagement of such shoulders provides support for the drill pipe being held without any of the problems associated with the prior art slips, regardless of the weight of the landing string and casing string.




The corresponding shoulders are so configured that they are fully rotatable with respect to each other. Hence, no specific radial alignment of the shoulders is required prior to or during engagement between said corresponding shoulders.











BRIEF DESCRIPTION OF THE DRAWINGS




For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein:





FIG. 1

is an overall elevational view of a drilling rig situated on a floating drill ship, said drilling rig supporting a landing string and casing string extending therefrom in accordance with the present invention toward the borehole that has been drilled into the sea floor.





FIG. 2

is an elevational view of drill pipe in accordance with the present invention.





FIGS. 3 and 4

are fragmentary, sectional, elevational views of drill pipe in accordance with the present invention.





FIG. 5

is a perspective view of a first embodiment of the wedge members of the lower and upper holders of the present invention, hinged together and closed.





FIG. 6

is a cross sectional view taken along lines


6





6


in FIG.


5


.





FIG. 7

is a perspective view of the first embodiment of the individual, unconnected wedge members of the lower and upper holders of the present invention.





FIG. 8

is a perspective view of the first embodiment of the wedge members of the lower and upper holders of the present invention hinged together in an open position.





FIG. 9

is a fragmentary, sectional, elevational view of an alternative embodiment of drill pipe in accordance with the present invention, along with a side view of a wedge member used with the alternative embodiment in both the upper and lower holders of the present invention.





FIG. 10

is an elevational view of the drill pipe and a first embodiment of the upper and lower holders in accordance with the present invention, in which the lower holder is supporting the landing string extending from the drilling rig, and the auxiliary upper holder is supporting the weight of the joints of drill pipe being added to or removed from the landing string.





FIG. 11

is an elevational view of the drill pipe and the first embodiment of the holders in accordance with the present invention, wherein the landing string is being supported by the lower holder, and wherein additional joints of drill pipe have either been just added to or are about to be removed from the landing string being held by the lower holder.





FIG. 12

in an elevational view of the drill pipe and the first embodiment of the holders in accordance with the present invention, wherein the landing string is supported by the upper holder, and wherein the upper holder and the wedges of the lower holder are being raised slightly so as to clear the wedge members of the lower holder from around the drill pipe prior to lowering the joints of drill pipe which have been added, or, alternatively, where the upper holder has just been used to pull several joints of landing string up as in “tripping out” of the hole.





FIG. 13

is a perspective view showing the first embodiment of the upper holder without its wedge members and without the auxiliary upper holder.





FIG. 14

is a cross sectional view taken along lines


14





14


of FIG.


13


.





FIG. 15

is an elevational view of the drill pipe and the first embodiment of the upper and lower holders of the present invention wherein the upper holder has just lowered the drill pipes that were added and wherein the weight of the landing string is about to be transferred from the upper holder to the lower holder.





FIG. 16

is an elevational view of the drill pipe and the first embodiment of the upper and lower holders of the present invention wherein the lower holder is supporting the weight of the landing string and wherein the upper holder is about to be hoisted up so that additional joints of drill pipe may be added to the landing string or, alternatively, wherein the upper holder is about to engage and support the landing string in preparation for “tripping out” of the hole.





FIG. 17

is an elevational view of an alternative embodiment of the drill pipe in accordance with the present invention.





FIG. 18

is a cross sectional view taken along lines


18





18


of FIG.


17


.





FIG. 19

is an elevational view of an alternative embodiment of drill pipe in accordance with the present invention.





FIG. 19A

is a cross sectional view taken along lines


19


A—


19


A of FIG.


19


.





FIG. 20

is an elevational view of an alternative embodiment of the present invention in which the joints are run with the female end down and the male end up.





FIG. 21

is an elevation view of another alternative embodiment of drill pipe in accordance with the present invention.





FIG. 21



a


is a cross sectional view taken along lines


21




a





21




a


of FIG.


21


.





FIG. 22

is an elevation view of yet another alternative embodiment of the present invention.





FIG. 23

is an elevational side view of a second embodiment of wedge members in accordance with the present invention.





FIG. 24

is an elevational view of the preferred embodiment of the upper and lower holders in accordance with the present invention.





FIG. 25

is a fragmentary elevational view of the preferred embodiment of the lower holder of the present invention showing the wedge members of the lower holder in a disengaged or removed position.





FIG. 25A

is a fragmentary elevational view of the preferred embodiment of the lower holder of the present invention showing the wedge members of the lower holder in an engaged position.





FIG. 26

is a plan view taken along lines


26





26


of FIG.


25


.





FIG. 27

is a partial perspective view of the preferred embodiment of the lower holder of the present invention showing the wedge members of the lower holder in a removed position.





FIG. 28

is a partial elevational view of the preferred embodiment of the upper holder of the present invention showing the wedge members of the upper holder in a disengaged position.





FIG. 29

is an elevation view taken along lines


29





29


of FIG.


28


.





FIGS. 30 through 33

depict a further alternative embodiment of the apparatus of the present invention showing a conduit or umbilical cord running along the outside of the drill pipe wherein said conduit is accommodated by a groove in the lower holder, but which in all other respects corresponds to the views shown in

FIGS. 24 through 27

, respectively.





FIG. 34

is an elevational view of a cross section taken through the center of the lower holder, showing the preferred embodiment of the wedge members in accordance with the present invention, with the wedge members in a disengaged position.





FIG. 35

is an elevational view of a cross section taken through the center of the lower holder, showing the preferred embodiment of the wedge members in accordance with the present invention, with the wedge members in an engaged position about the drill pipe.





FIG. 36

is an elevational view of the cross section of the preferred embodiment of the wedge members shown in FIGS.


34


and


35


.











DETAILED DESCRIPTION OF THE INVENTION





FIG. 1

depicts generally the present invention


5


in overview. As shown in

FIG. 1

, drill ship


10


has drilling rig


8


that is situated above ocean surface


12


over the location of undersea well


14


that is drilled below sea floor


16


. Numerous lengths or “joints” of drill pipe


18


in accordance with the present invention, attached end-to-end and collectively known as “landing string”


19


, extend from rig


8


. Numerous lengths or “joints” of casing


34


, attached end-to-end and collectively known as “casing string”


35


, extend below landing string


19


and are attached to landing string


19


via crossover connection


36


. The landing string


19


, crossover connection


36


and casing string


35


are situated longitudinally within riser


17


which extends from the rig


8


to undersea well


14


.





FIG. 2

shows a drill pipe


18


in accordance with the present invention. In addition to a female or “box” end


20


and a male or “pin” end


22


, drill pipe


18


of the present invention also has an enlarged diameter section


21


which is spaced apart from box end


20


and pin end


22


. Enlarged diameter section


21


has a shoulder


21




a


which is preferably tapered as shown in

FIGS. 2 and 3

. Shoulder


21




a


surrounds at least a part and preferably all of the circumferential perimeter of drill pipe


18


.




Also in accordance with the present invention,

FIG. 10

shows lower drill pipe holder


100


for supporting the landing string


19


during the addition or removal of one or more joints of drill pipe


18


to or from landing string


19


. Lower holder


100


is preferably located at the drilling rig floor


9


, where it may be situated in or adjacent to the floor.




As also shown in

FIG. 10

, lower holder


100


includes main body


104


which generally surrounds an opening


11


in rig floor


9


through which landing string


19


protrudes. Main body


104


has an opening


103


and a tapered inner face


105


which defines a tapered bowl generally surrounding landing string


19


which protrudes therethrough.




Lower holder


100


also includes one or more wedge members


106


, as depicted in

FIGS. 10

,


11


and


12


. As shown in

FIG. 7

, the wedge members


106


of the present invention can be three in number and may be connected by hinges


108


as shown in

FIGS. 5 and 8

. Wedge members


106


have a tapered outer face


107


, as shown in

FIGS. 5 and 7

, which corresponds with the tapered inner face


105


of main body


104


, as shown in

FIGS. 11 and 12

. The tapered bowl in main body


104


which is defined by its tapered inner face


105


receives wedge members


106


as best depicted in

FIGS. 10 and 11

.




As shown in

FIGS. 6 and 7

, the inner side of wedge member


106


has a tapered shoulder


109


. Tapered shoulder


109


corresponds with tapered shoulder


21




a


of enlarged diameter section


21


of drill pipe


18


, as best shown in

FIGS. 11 and 12

. Tapered shoulder


109


of wedge member


106


is curved, as shown in

FIGS. 7 and 8

, to correspond with the curved, circumferential shape of shoulder


21




a


of enlarged diameter section


21


. The inner side of wedge member


106


also has a curved surface


106




a


, as best shown in

FIGS. 7 and 8

, which corresponds with and accommodates the curved outer surface


18




a


of drill pipe


18


. The inner side of wedge member


106


also has curved surface


106




b


, as best shown in

FIGS. 7 and 8

, which corresponds with and accommodates the curved outer surface


21




b


of enlarged diameter section


21


of drill pipe


18


.




When wedge members


106


are in place in main body


104


, as shown in

FIGS. 10 and 11

, the wedge members form an interface between body


104


and the joint of drill pipe


18


being held by holder


100


, the engagement between shoulder


109


of wedge member


106


and shoulder


21




a


of enlarged diameter section


21


providing support for the drill pipe


18


being held by the holder


100


.




It should be understood that lower holder


100


of the present invention provides support for landing string


19


by the engagement of shoulder


109


of wedge member


106


with shoulder


21




a


of enlarged diameter section


21


of drill pipe


18


. Accordingly, unlike prior art slips, it is not necessary for the curved inner surface


106




a


of wedge member


106


to have teeth-like grippers or bear against the drill pipe


18


being supported by the holder. Hence, the present invention overcomes the problems associated with crushing, deformation, scoring and uneven distribution of gripping force associated with prior art slips.




It should be understood that drill pipe


18


, depicted in

FIG. 10

as being supported by lower holder


100


, is the uppermost length or “joint” of drill pipe in landing string


19


depicted in FIG.


1


. It should also be understood that lower holder


100


of the present invention supports not only drill pipe


18


which appears in

FIG. 10

, but also the entire attached landing string


19


and casing string


35


extending from rig


8


, as best shown in FIG.


1


. In extremely deep wells drilled in extremely deep water for which the present invention is particularly suited, the combined weight of landing string


19


and casing string


35


may range from 950,000 to 2,300,000 pounds. In the future, as deeper wells are drilled in deeper water, it is expected that the present invention may be supporting combined landing string and casing string weight of 4,000,000 pounds or more.





FIG. 1

depicts the installation or “running” of intermediate casing string


35


, which will be lowered longitudinally, through blowout preventors


15


and surface casing


32


, into position in borehole


24


. Although

FIG. 1

shows surface casing


32


already cemented into position in borehole


24


, it should be understood that the present invention may not only be used to run intermediate casing, but surface and production casing as well. It should also be understood that the present invention, in addition to being used to land casing strings, may also be used to land any other items on or below the sea floor such as blow out preventors, subsea production facilities, subsea wellheads, production strings, drill pipe and drill bits. It should be specifically understood that drill pipe


18


of the present invention may be used in the drilling operation, with drilling fluid being circulated through the lumen


23


of drill pipe


18


.




In order to lower casing string


35


from the position shown in

FIG. 1

into borehole


24


, additional joints of drill pipe


18


are added, usually 1 to 4 at a time, above the joint of drill pipe


18


being held by holder


100


, as shown in FIG.


10


.

FIG. 10

shows three additional joints of drill pipe


18


about to be added, although it should be understood that the number of joints of drill pipe added at a time may vary.




After the additional joint or joints of drill pipe


18


have been attached, as shown in

FIG. 11

, landing string


19


and attached casing string


35


may be lowered by a distance roughly equivalent to the length of the newly added joints of drill pipe. This is accomplished via upper holder


200


of the present invention, as depicted in FIG.


11


. Upper holder


200


is supported by elevator bails or “links”


210


which in turn are attached to the rig lifting system (not shown). Upper holder


200


includes a main body


204


having an opening


203


which may accommodate the passage of drill pipe


18


therethrough. The opening


203


of main body


204


has a tapered inner face


205


which defines a tapered bowl, as best shown in FIG.


13


.




Upper holder


200


also includes one or more wedge members


206


having a tapered outer face


207


which corresponds with the tapered inner face


205


of main body


204


. The tapered bowl in main body


204


defined by its tapered inner face


205


receives wedge members


206


as shown in

FIGS. 11 and 12

. Wedge members


206


of the present invention may be three in number and may be connected by hinges, similar to wedge members


106


as depicted in

FIGS. 5 and 7

.




Wedge members


206


of upper holder


200


may be shaped and configured similar to wedge members


106


of lower holder


100


, although there may be slight variations in size and/or dimensions between wedge members


106


and


206


. Similar to tapered shoulder


109


of wedge member


106


as depicted in

FIGS. 6 through 8

, the inner side of wedge member


206


has a tapered shoulder


209


. As shown in

FIG. 11

, tapered shoulder


209


of wedge member


206


corresponds with tapered shoulder


20




a


of box end


20


of drill pipe


18


. Similar to tapered shoulder


109


of wedge member


106


, tapered shoulder


209


of wedge member


206


is curved to correspond with and accommodate the curved, circumferential shape of shoulder


20




a


of box end


20


.




When wedge members


206


are in place in main body


204


, as shown in

FIG. 12

, the engagement between shoulder


209


of wedge member


206


and shoulder


20




a


of box end


20


of drill pipe


18


being held by holder


200


provides support for said drill pipe


18


being held by holder


200


. Similar to curved surface


106




a


on the inner side of wedge member


106


as shown in

FIGS. 7 and 8

, the inner side of wedge member


206


also has a curved surface


206




a


which corresponds with and accommodates the curved outer surface


18


A of drill pipe


18


. Similar to curved surface


106




b


on the inner side of wedge member


106


as best shown in

FIGS. 7 and 8

, the inner side of wedge member


206


also has a curved surface


206




b


which corresponds with and accommodates the curved outer surface


20




b


of box end


20


of drill pipe


18


.




When wedge members


206


are in place in main body


204


of upper holder


200


, as shown in

FIG. 12

, said wedge members form an interface between body


204


and the joint of drill pipe


18


being held by holder


200


. In that position, as depicted in

FIG. 12

, the rig lifting system (not shown) can be used to slightly lift upper holder


200


. When that happens, upper holder


200


is supporting the entire load including the landing string


19


and casing string


35


, thereby taking the load off wedge members


106


of lower holder


100


. Wedge members


106


can then be disengaged, i.e., wholly or partially moved up and away from drill pipe


18


, providing sufficient clearance for the landing string


19


to pass unimpeded through the opening


103


in main body


104


of lower holder


100


.




The rig lifting system may then be used to lower upper holder


200


, along with the landing string and casing string it is supporting, by a distance roughly equivalent to the length of the newly added joints of drill pipe. More specifically, upper holder


200


is lowered until the uppermost enlarged diameter section


21


of newly added drill pipe


18


is located a distance above main body


104


of holder


100


sufficient to provide the vertical clearance needed for reinsertion of wedge members


106


in main body


104


, as shown in FIG.


15


. At that point, wedge members


106


of lower holder


100


may be placed back into position in main body


104


of holder


100


. Upper holder


200


may then be slightly lowered further so as to bring into supporting engagement shoulder


109


of wedge members


106


with shoulder


21




a


of the uppermost enlarged diameter section


21


of newly added drill pipe


19


, as shown in FIG.


16


. In this fashion, the entire load including the landing string and the casing string is transferred from upper holder


200


to lower holder


100


.




Upper holder


200


can then be cleared away from the uppermost end of the landing string. This is accomplished by lowering holder


200


slightly such that wedge members


206


can be disengaged, i.e., moved up and away from box end


20


that was previously being held by holder


200


, as shown in FIG.


16


. Holder


200


can then be hoisted up by the rig lifting system, permitting clearance for yet additional joints of drill pipe to be added to the upper end of the landing string.




As this process is repeated over and over again, casing string


35


is lowered further and further. This process continues until such time as casing string


35


reaches its proper location in borehole


24


, at which point the overall length of landing string


19


spans the distance between rig


8


and undersea well


14


.




It should be understood that the rig lifting system referenced herein may be a conventional system available in the industry, such as a National Oilwell 2040-UDBE draworks, a Dreco model “872TB-1250” traveling block and a Varco-BJ “DYNAPLEX” hook, model 51000, said system being capable of handling in excess of 2,000,000 pounds.




Some rigs have specialized equipment to hold aloft additional joints of drill pipe as they are being added to the landing string. However, for those rigs that do not have such specialized equipment, the present invention provides for auxiliary upper holder


300


, as shown in

FIGS. 10 and 11

. Auxiliary holder


300


is suspended below upper holder


200


by connectors


301


. Connectors


301


may be cables, links, bails, slings or other mechanical devices which serve to connect auxiliary holder


300


to upper holder


200


.




Auxiliary holder


300


has a main body


304


which can be moved from an opened to a closed position, allowing it to capture and hold aloft the joints of drill pipe


18


to be added to the pipe string, as shown in FIG.


10


. The inner surface of main body


304


includes a tapered shoulder which corresponds with tapered shoulder


21




a


. The inner surface of main body


304


is sized to accommodate drill pipe


18


such that when main body


304


is in its closed position and supporting the joints of drill pipe to be added, as shown in

FIG. 10

, the tapered shoulder of main body


304


engages tapered shoulder


21




a


, providing support for the joints of drill pipe being added. When upper holder


200


is to be used to lower the entire load to the position shown in

FIG. 15

, auxiliary holder


300


can be swung back, up and out of the way, so that it does not interfere with lower holder


100


. Because the combined weight of the relatively few joints of drill pipe being added at any one time is significantly less than the combined weight of the landing string and the casing string extending below the rig, the size and strength of auxiliary upper holder


300


may be substantially less than that of upper holder


200


. Auxiliary holder


300


may be a conventional elevator available in the industry, such as the 25-ton model “MG” manufactured by Access Oil Tools.




It should be understood that while the present invention is particularly useful for landing casing strings and other items, the invention may also be used to retrieve items. For example, the invention may be employed to retrieve the landing string and any items attached thereto, such as a drill bit, in an operation commonly referred to as “tripping out of the hole,” wherein the operations described hereinabove are essentially reversed. While the landing string is being supported by lower holder


100


, as shown in

FIG. 16

, upper holder


200


is lowered to the position shown in FIG.


16


. Wedge members


206


may then be lowered into main body


204


of upper holder


200


so that shoulder


209


of wedge member


206


is brought into supporting engagement with shoulder


20




a


of box end


20


.




At that point, the rig lifting system may be used to lift holder


200


, thereby transferring the landing string load from lower holder


100


to upper holder


200


. This allows wedge members


106


of lower holder


100


to be wholly or partially moved up and away from drill pipe


18


, providing sufficient clearance for pipe string


19


to pass unimpeded through the opening


103


in main body


104


.




When tripping out of the hole, it is common practice to pull up two or more joints at a time, as would be the case shown in FIG.


12


. The landing string would be pulled up by upper holder


200


such that the enlarged diameter section


21


of the drill pipe to be held by lower holder


100


is slightly above wedge members


106


, as is shown in FIG.


12


. At that point, wedge members


106


would be lowered into position in main body


104


. Upper holder


200


may then be slightly lowered further so as to bring into supporting engagement shoulder


109


of wedge member


106


with shoulder


21




a


of enlarged diameter section


21


of the drill pipe being held in holder


100


. In this fashion, the entire load is transferred to lower holder


100


, permitting the drill pipe that has been pulled up above holder


100


to be detached from the landing string, as would appear in FIG.


10


. The removed joints of drill pipe would then be cleared from the upper holder and placed on the drilling rig, permitting upper holder


200


to be lowered again so that more joints of drill pipe could be pulled up, as this process is repeated over and over again until all of the landing string and the items attached thereto have been retrieved.




As shown in

FIGS. 2-4

, drill pipe


18


of the present invention has the following exemplary dimensions:




The end outside diameter (E.O.D.) of pin end


22


and box end


20


is preferably in the range between about 6½ to 9⅞ inches, and most preferably between 7½ and 9 inches.




The end wall thickness (E.W.T.) of pin end


22


and box end


20


is preferably in the range between about 1½ to 3 inches, and most preferably between 1⅞ and 2½ inches.




The pipe inside diameter (P.I.D.), i.e., the diameter of the uniform bore or lumen


23


extending throughout the length of drill pipe


18


, is preferably in the range between about 2 to 6 inches, and most preferably between 2⅞ and 5 inches.




The pipe wall thickness (P.W.T.), i.e., the thickness of the pipe wall throughout the length of drill pipe


18


, except at the ends and at the enlarged diameter section, is preferably in the range between about ⅝ to 2 inches, and most preferably between ⅞ and 1½ inches.




The pipe outside diameter (P.O.D.), i.e., the outside diameter of drill pipe


18


throughout its length, except at the ends and at enlarged diameter section


21


, is preferably in the range between about 4½ to 7⅝ inches, and most preferably between 5 and 7 inches.




The enlarged diameter wall thickness (E.D.W.T.), i.e., the thickness of the pipe wall at enlarged diameter section


21


, is preferably in the range between about 1½ to 3 inches, and most preferably between 1⅞ and 2½ inches.




The length “L” of drill pipe


18


is preferably in the range between about 28 to 45 feet, and most preferably between 28 and 32 feet. It should be understood that length “L” may be any length that can be accommodated by the vertical distance between the rig floor and the highest point of the rig.




The length of the enlarged diameter section (L. E.) is preferably in the range between about 1 to 60 inches, and most preferably between 6 and 12 inches.




The distance “D” between shoulder


21




a


and shoulder


20




a


is preferably in the range between about 2 to 11 feet, most preferably between 3 to 5 feet. The design criteria for distance “D” include the following: (a) the distance “D” should be sufficient to provide adequate clearance, and thereby avoid entanglement, between the bottom of holder


200


and the top of holder


100


when said holders are in the position depicted in

FIG. 16

; (b) the distance “D” should also be sufficient to permit insertion and removal of wedge members


206


into and out of the tapered bowl of upper holder


200


; and (c) the distance “D” should preferably be such that the uppermost end of the drill pipe being supported by lower holder


100


is a reasonable working height (R.W.H.) above rig floor


9


, as shown in

FIG. 10

, so as to permit rig personnel and/or automated handling equipment to assist in attaching or removing joints of drill pipe to or from said uppermost end.




The angle of taper “A” of shoulders


21




a


,


20




a


and


22




a


, which appear in

FIGS. 3 and 4

, can be any angle greater than 0° and less than 180°, preferably between 10 degrees and 45 degrees, and most preferably 18 degrees. The same angle “A” applies to the angle of taper of shoulder


109


of wedge member


106


and shoulder


209


of wedge member


206


, as shown in FIG.


6


.




As shown in

FIGS. 6 and 7

, wedge members


106


and


206


of the present invention have the following exemplary dimensions:




The height (“H-1”) of the wedge members is preferably in the range of about 5 to 20 inches, and most preferably between 8 and 16 inches.




The distance (“H-2”), i.e., the vertical height of the shoulder of the wedge member, is preferably in the range of about 2 to 10 inches, and most preferably between 3 and 8 inches.




The distance (“H-3”) between the bottom of the wedge members and the bottom of shoulders


109


,


209


is preferably in the range of about 3 to 10 inches, and most preferably between 41′ and 8 inches.




The top thickness (“T-1”) of the wedge members is preferably in the range of about 1 to 8 inches, and most preferably between 2 and 6½ inches.




The thickness (“T-2”) of the wedge members at shoulders


109


,


209


is preferably in the range of about 1½ to 8½ inches, and most preferably between 2½ and 6½ inches.




The bottom thickness (“T-3”) of the wedge members is preferably in the range of about ½ to 6 inches, and most preferably between ¾ and 4 inches.




The angle of taper (“A.T.”) of outer face


107


,


207


of the wedge members can be any angle greater than 0° and less than 180°, preferably between 10 degrees and 45 degrees.




As shown in

FIG. 14

, upper holder


200


of the present invention has the following exemplary dimensions:




The height of holder


200


(“H.H.”) is preferably in the range of about 18 to 72 inches, and most preferably between 24 and 48 inches.




The width of holder


200


(“W-1”) is preferably in the range of about 24 to 72 inches, and most preferably between 36 and 60 inches.




The width of the top of opening


203


(“W-2”) of holder


200


is preferably in the range of about 12 to 24 inches, and most preferably between 16 and 21 inches.




The width of the bottom of opening


203


(“W-3”) of holder


200


is preferably in the range of about 6 to 18 inches, and most preferably between 9 and 15 inches.





FIG. 9

depicts an alternative embodiment of the present invention wherein the shoulders, for example shoulders


21




a


and


20




a


, are square, i.e., wherein angle “A” measures 90 degrees. In that alternative embodiment as depicted in

FIG. 9

, the shoulders


109


and


209


, respectively, of wedge members


106


and


206


, respectively, are also square.




In the embodiment of the invention as depicted in

FIG. 12

, wedge members


106


are lifted out of position by a lifting apparatus which includes lifting arms


112


. Lifting arms


112


may be raised and lowered by way of an actuator


114


, preferably a pneumatic or hydraulic piston-cylinder arrangement. Lifting arms


112


may be attached directly to wedge members


106


or via connectors


111


as shown in FIG.


12


. Connectors


111


may be cables, links, bails, slings or other mechanical devices which serve to connect lifting arms


112


to wedge members


106


. Wedge members


106


preferably include lifting eye


115


to facilitate the connection to lifting arms


112


. It should be understood that the raising and lowering wedges


106


out of and into position in body


104


can be accomplished in a variety of ways, including manual handling by rig personnel. It should also be understood that the lifting apparatus for raising and lowering wedge members


106


must be sized and configured so as to permit sufficient clearance for upper holder


200


when it is in the position shown in

FIGS. 15 and 16

.




As depicted in

FIGS. 11 and 12

, upper holder


200


preferably includes a lifting apparatus for raising and lowering wedge members


206


out of and into position in main body


204


. In the embodiment of the invention as depicted in

FIG. 12

, the lifting apparatus includes lifting arms


212


. Lifting arms


212


may be moved up and down by actuator


214


, preferably a hydraulic or pneumatic piston-cylinder arrangement. Lifting arms


212


may be attached directly to wedge members


206


or via connectors


211


. Connector


211


may be cables, links, bails, slings or other mechanical devices which serve to connect lifting arms


212


to wedge members


206


. Wedge members


206


preferably include lifting eyes


215


to facilitate the connection to lifting arms


212


.




In the embodiment of the invention as shown in

FIG. 13

, upper holder


200


is removably attached to elevator links


210


. Main body


204


of upper holder


200


is preferably comprised of steel having recessed areas


220


to accommodate therein placement of elevator link eyes


221


. Elevator link eyes


221


are retained in the position shown in

FIGS. 13 and 14

by link retainers


222


. Link retainers


222


may be moved from the closed position shown in

FIG. 14

to an open position by lifting release pins


224


, thereby permitting retainer links


222


to pivot about hinge pin


225


to an open position, thus permitting removal of upper holder


200


from elevator links


210


. As best depicted in

FIG. 12

, upper holder


200


is also provided with lifting eyes


230


to which connectors


301


may be attached.





FIGS. 17 and 18

depict an alternative embodiment of the present invention in which enlarged diameter section


21


is not enlarged completely around the circumference of drill pipe


18


. In this alternative embodiment of enlarged diameter section


21


, shown in cross section in

FIG. 18

, there may be one or more cross sectional gaps in section


21


where the diameter is not enlarged.




In the preferred embodiment of the invention, drill pipe


18


, including box end


20


, enlarged diameter section


21


and pin end


22


, is made from a single piece of pipe of uniform wall thickness having the dimension E.W.T. in

FIG. 4

, said thickness being reduced at intervals along the pipe by milling between box end


20


and enlarged diameter section


21


, and by milling between pin end


22


and enlarged diameter section


21


. It should be understood that in such preferred embodiment of the invention, box and pin ends


20


and


22


and enlarged diameter section


21


are integral with the pipe, i.e., box end


20


and pin end


22


are not created by welding or otherwise attaching said ends to drill pipe


18


, nor is enlarged diameter section


21


created through welding or other means of attachment. In the preferred embodiment of the invention, each joint of drill pipe


18


is made of steel and weighs between 800 to 5,000 pounds, most preferably between 1,000 to 2,000 pounds, or approximately 29 to 110 pounds per linear foot, most preferably 32 to 75 pounds per linear foot.




Alternatively, drill pipe


18


of the present invention may be made of a piece of pipe of uniform thickness, referenced as P.W.T. in

FIG. 4

, with attached box and pin ends, and with an attached enlarged diameter section


21


. In this alternative embodiment, the box end, pin end and enlarged diameter section may be attached to the pipe by welding, bolting or other means.




In a further alternative embodiment of the present invention, drill pipe


18


may be made from titanium or from a carbon graphite composite.





FIGS. 19 and 21

show further alternative embodiments of the present invention in which drill pipe


18


, having a length “L”, is comprised of two separate drill pipes,


18


S and


18


L, the former being shorter than the latter, each one having a female end


20


and a male end


22


. As shown in

FIGS. 19 and 21

,


18


S is attached end-to-end with 18L. In the alternative embodiment depicted in

FIG. 19

, the mated male end


22


and female end


20


combine to form enlarged diameter section


21


, having a tapered shoulder


21




a


defined by the tapered shoulder of mated female end


20


. In the alternative embodiment depicted in

FIG. 21

, the mated female end


20


serves as enlarged diameter section


21


, with the shoulder of said mated female end serving as shoulder


21




a.






In yet a further alternative embodiment of the present invention shown in

FIG. 22

, an extra tapered shoulder


25


is provided on drill pipe


18


between enlarged diameter section


21


and the end of the drill pipe. In this embodiment of the invention, extra tapered shoulder


25


has an angle of taper “A” that corresponds with and is engaged by shoulder


209


of wedge members


206


, thereby providing support for the drill pipe being held by upper holder


200


. In this embodiment, “D” is the distance between shoulder


21




a


and shoulder


25


.




The distance “D”, the angle “A” and the length “L” in the alternative embodiment shown in

FIGS. 17

,


19


,


21


and


22


are comparable to those of the preferred embodiment as shown in FIG.


3


.





FIG. 23

depicts a second embodiment of wedge members


106


,


206


in accordance with the present invention. The dimensions H-1, H-2, H-3, T-1, T-2 and T-3, and the angles A and A.T. in the embodiment shown in

FIG. 23

are comparable to those of the embodiment as shown in FIG.


6


.




It should be understood that in an alternative embodiment of the present invention, the drill pipe may be run with the male or pin end


22


up and the female or box end


20


down, as depicted in FIG.


20


. In this alternative embodiment of the invention, tapered shoulder


209


of wedge member


206


corresponds with tapered shoulder


22




a


of pin end


22


of drill pipe


18


; shoulder


209


is curved to correspond with and accommodate the curved, circumferential shape of shoulder


22




a


; and curved surface


206




b


of wedge member


206


corresponds with and accommodates the curved outer surface


22




b


of drill pipe


18


.




Crossover connection


36


depicted in

FIG. 1

may include an “SB” Casing Hanger Running Tool in conjunction with an “SB” Casing Hanger, all manufactured by Kvaerner National Oilfield Products.





FIGS. 24-29

show the preferred embodiment of the apparatus of the present invention in which the upper and lower holders shown and described with respect to

FIGS. 10-16

and


20


are replaced by preferred constructions for the upper and lower holders. In

FIG. 24

, the preferred embodiment for the upper holder is designated generally by the numeral


40


. In

FIG. 24

, the preferred embodiment for the lower holder is designated by the numeral


70


. The lower holder


70


is shown in more detail in

FIGS. 25

,


25


A,


26


and


27


. The upper holder


40


is shown in more detail in

FIGS. 28 and 29

.




In

FIGS. 24-27

, lower holder


70


includes a main body


41


having a cylindrically shaped bore


42


extending to the lower surface


41


A of body


41


and a frustoconically shaped tapered face


43


extending to the upper surface


41


B of body


41


. A pair of wedge members


44


can be inserted (

FIG. 25A

) or removed (

FIGS. 25 and 27

) from the main body


41


. Each of the wedge members


44


has an outer tapered face


45


that is of a corresponding shape to the tapered face


43


of main body


41


. Wedge members


44


are movable with respect to main body


41


between engaged and disengaged positions. When wedge members


44


are in place in main body


41


of lower holder


70


, as shown in

FIG. 25A

, said wedge members


44


form an interface between body


41


and the joint of drill pipe


18


being held by lower holder


70


, the engagement between shoulder


62


of wedge member


44


and shoulder


21




a


of enlarged diameter section


21


providing support for the drill pipe


18


being held by the holder


70


.




In order to move the wedge members


44


in to the engaged position (FIG.


25


A), and out to the disengaged position (FIG.


25


), one or more actuators such hydraulic cylinders


50


can be provided. The hydraulic cylinders


50


each have opposing end portions and are preferably attached at one end portion to main body


41


. At an opposing end portion, each hydraulic cylinder


50


may be attached pivotally to a lifting arm


55


of each wedge member


44


.




As shown in

FIGS. 26-27

, there are preferably two lifting arms


55


, one for each wedge member


44


, and preferably two hydraulic cylinders


50


, one for each lifting arm


55


. The lifting arms


55


may be pivotally attached to main body


41


. Body


41


preferably includes a mounting plate


41


D, best shown in

FIGS. 26 and 27

, which facilitates placement and attachment of lifting arms


55


to body


41


. As shown in

FIGS. 25

,


25


A,


26


and


27


, each lifting arm


55


can be pivotally attached at padeyes


46


to main body


41


. This pivotal connection can be achieved using a pivot pin


47


or pinned connection that extends through the padeye


46


and into socket


49


provided in the lifting arms


55


, as best shown in FIG.


26


. Arrows


48


in

FIG. 27

schematically illustrate the movement of wedge members


44


between the engaged, pipe holding position of FIG.


25


A and the disengaged position of FIG.


25


.




Each hydraulic cylinder


50


may be pivotally attached with a pivotal connection


52


to main body


41


. Pivotal connection


52


preferably includes padeyes


53


on main body


41


which receive an end portion of hydraulic cylinder


50


, and pin


54


, as best shown in

FIGS. 26 and 27

.




A pivotal connection


63


can be provided between each pushrod


51


of cylinder


50


and an arm


55


as shown in

FIGS. 25

,


25


A,


26


and


27


. The pivotal connection


63


is spaced from the pivotal connection at pin


47


, as best shown in

FIGS. 25 and 25A

. The hydraulic cylinder


50


can be filled with hydraulic fluid transmitted via flowlines


58


, causing the pushrod to extend as shown in

FIGS. 25

,


26


and


27


, or to retract as shown in FIG.


25


A. When the pushrod is moved from its retracted position of

FIG. 25A

to its extended position of

FIG. 25

, pushrod


51


rotates its connected lifting arm


55


about pivot pin


47


as schematically indicated by the arrows


60


in FIG.


25


A.




Pinned connections


59


can be provided for connecting each of the wedge members


44


to a lifting arm


55


, as shown in FIG.


26


. Each lifting arm


55


preferably has two, curved free-end portions


56


, each such free-end portion


56


having a curved slot


57


, as best shown in

FIGS. 25 and 27

. The curved free-end portion


56


and slot


57


of each lifting arm


55


are so configured that when the lifting arms


55


are lowered to the position shown in

FIG. 25A

, the wedge members


44


closely conform to the drill string


18


. In this position (FIG.


25


A), shoulder


62


provided on each of the wedge members


44


is configured to receive a correspondingly shaped shoulder on the drill pipe


18


being held by holder


70


, such as the annular shoulder


21




a


on the enlarged diameter section


21


of the drill pipe


18


that is shown in FIG.


2


.




Each wedge member


44


preferably has an accommodating recess


61


for each curved free end


56


of lifting arm


55


, as shown in

FIGS. 26 and 27

. Each pinned connection


59


joins each curved free end


56


at slot


57


to a wedge member


44


. Each pinned connection


59


preferably includes a pin member


64


that extends through curved free end


56


and into socket


65


on wedge members


44


. In the engaged position of

FIG. 25A

, the pin member


64


locates at an end portion of slot


57


closest to drill pipe


18


. In the disengaged position of

FIG. 25

, the pin member


64


locates at an end portion of slot


57


furthest away from drill pipe


18


.




The preferred embodiment of upper holder


40


is shown in

FIGS. 24

,


28


,


29


. Upper holder


40


has main body


41


C with a vertical, open-ended bore that preferably includes cylindrically shaped section


42


A and frustoconically shaped tapered face


43


A. As with lower holder


70


, upper holder


40


has wedge members


44


that hold the drill pipe


18


by engaging a shoulder on each wedge member with a shoulder on the drill pipe


18


being held by upper holder


40


.




The wedge members


44


of upper holder


40


are preferably moved between engaged and disengaged positions using the same mechanism provided for the lower holder


70


as shown in

FIGS. 24-27

and as described herein. Thus, the upper holder


40


preferably has the same wedge members


44


, hydraulic cylinders


50


and lifting arms


55


as the lower holder


70


, including all of the structure shown in

FIGS. 24-27

. The tapered face


43


A of main body


41


C of upper holder


40


, similar to tapered face


43


of lower holder


70


, receives tapered outer faces


45


of wedge members


44


. The upper holder


40


preferably differs from the lower holder


70


in that the upper holder


40


may also have lifting means, such as lifting eyes


213


, that enable main body


41


C to be lifted by elevator links


210


.




The preferred embodiment of wedge members


44


is depicted in

FIGS. 34-36

. The configuration and shape of wedge members


44


of lower holder


70


are similar to that of wedge members


44


of upper holder


40


, although there may be slight variations in size and/or dimensions of such wedge members. The dimensions H-1, H-2, H-3, T-1, T-2 and T-3, and the angles A and A.T. in the preferred embodiment shown in

FIGS. 34-36

are comparable to those of the embodiments shown in

FIGS. 23 and 6

, with preferred dimensions as follows: H-1 is 11 inches; H-2 is 3.08 inches; H-3 is 4.92 inches; T-1 is 6.465 inches; T-2 is 4.87 inches; T-3 is 0.84 inches; and A is 18°.




The preferred embodiment of the wedge members shown in

FIGS. 34 through 36

, in addition to having tapered outer face


45


with a preferred angle of taper (A.T.) of 45°, also has a second tapered outer face


45


-


2


with a preferred angle of taper (A.T.-2) of 9.5°. As shown in

FIGS. 34 and 35

, main body


41


preferably includes a second tapered face


43


-


2


which corresponds to and accommodates second tapered outer face


45


-


2


of wedge member


44


. Second tapered faces


45


-


2


and


43


-


2


serve to help guide the wedge members into main body


41


when the wedge members are being placed into their engaged position. Second tapered faces


45


-


2


and


43


-


2


also help to prevent the wedge members from becoming lodged or “stuck” in main body


41


, thereby facilitating movement of the wedge members from the engaged to the disengaged position.




When lowering or raising a landing string to or from the sea floor, it is sometimes desirable to simultaneously lower or raise a conduit or “umbilical cord”


80


along with and on the outside of the drill pipe


18


as shown in

FIGS. 30 through 32

. Umbilical cord


80


typically includes items such as hydraulic lines, electrical wires and/or miscellaneous cables. To accommodate such an umbilical cord


80


, lower holder


70


may be provided with an umbilical cord clearance groove


82


, as depicted in the embodiment of the lower holder


70


shown in

FIGS. 30-33

. Umbilical cord clearance groove


82


is sized so as to permit umbilical cord


80


to pass safely therethrough, thereby protecting umbilical cord


80


from being crushed or otherwise damaged as it is lowered and raised with the landing string. Umbilical cord


80


may be stored on a spool (not shown) located on or near the drilling rig floor


9


, such that umbilical cord


80


is fed with and positioned next to the drill pipe


18


as the drill pipe is being lowered or raised through the drilling rig floor.




The shoulders of the wedge members of the present invention, such as shoulder


109


(

FIG. 8

) and shoulder


62


(FIG.


26


), and the corresponding shoulders of the drill pipe, such as shoulders


20




a


and


21




a


(FIG.


2


), are preferably surfaces which are each defined by rotating a line 360° about the central longitudinal axis of the drill pipe. Said corresponding shoulders are so configured that they are rotatable 360° with respect to each other, regardless of the distance between said corresponding shoulders.




For example, corresponding shoulders


109


and


21




a


are fully rotatable with respect to each other, even when closely positioned next to each other just prior to their engagement and loading. Accordingly, no specific radial alignment of the corresponding shoulders is necessary prior to or during their engagement. This feature is important because the radial orientation of the drill pipe vis-a-vis the holder can be extremely difficult to change, thereby making it advantageous for said corresponding shoulders to be functionally engageable regardless of their radial alignment.




It should be understood that drilling rig


8


includes a drill platform having floor


9


with a work area for the rig personnel who assist in the various operations described herein. Although

FIG. 1

shows drilling rig


8


situated on a drill ship


10


, it should be understood that the present invention may be used on drilling rigs situated on platforms that are permanently affixed to the sea floor, or on semi-submersible and other types of deep water rigs. Moreover, although the invention is particularly useful for rigs drilling in deep water, the invention may also be used with shallow-water rigs and with rigs drilling on land.




The following table lists the part numbers and part descriptions as used herein and in the drawings attached hereto:




Parts List




The following is a list of parts of the various elements of the embodiments of the present invention.
















PART NUMBER




DESCRIPTION











 5




invention in general overview






 8




drilling rig






 9




drilling rig floor






 10




drill ship






 11




opening in drilling rig floor






 12




surface of ocean






 14




undersea well






 15




blowout preventors






 16




sea floor






 17




riser






 18




drill pipe






 18a




curved outer surface of drill pipe






 18S




shorter joint of drill pipe of alternative







embodiment






 18L




longer joint of drill pipe of alternative







embodiment






 19




landing string






 20




box (female) end of drill pipe






 20a




tapered shoulder of box end






 20b




curved outer surface of box end






 21




enlarged diameter section of drill pipe






 21a




supporting shoulder of enlarged diameter section






 21b




curved outer surface of enlarged diameter section






 22




pin (male) end of drill pipe






 22a




tapered shoulder of pin end






 22b




curved outer surface of pin end






 23




lumen of drill pipe 18






 24




borehole






 25




extra tapered shoulder






 26




earthen formation






 28




wall of borehole






 32




surface casing






 34




intermediate casing






 35




casing string






 36




crossover connection






 40




upper holder of preferred embodiment






 41




main body of lower holder 70






 41A




lower surface of main body 41






 41B




upper surface of main body 41






 41C




main body of upper holder 40






 41D




mounting plate of main body 41






 42




cylindrically shaped bore of main body 41






 42A




cylindrically shaped bore of main body 41C






 43




tapered face of main body 41 of lower holder






 43-2




second tapered face of main body 41 of lower







holder






 43A




tapered face of main body 41C of upper holder






 44




wedge member






 45




tapered outer face of wedge member 44






 45-2




second tapered outer face of the preferred







embodiment of wedge member 44






 46




padeye






 47




pivot pin






 48




arrow






 49




socket in lifting arm 55






 50




hydraulic cylinder






 51




pushrod






 52




pivotal connection






 53




padeye






 54




pin






 55




lifting arm






 56




curved free-end portion of lifting arm 55






 57




curved slot in curved free end 56






 58




hydraulic flowline






 59




pinned connection






 60




arrow






 61




recess in wedge member 44






 62




shoulder of wedge member 44






 63




pivotal connection






 64




pin member of pinned connection 59






 65




socket of pinned connection 59






 70




lower holder of preferred embodiment






 80




umbilical cord






 82




umbilical cord clearance groove






100




lower holder






103




opening in main body 104






104




main body of lower holder






105




tapered inner face of main body 104






106




wedge members of lower holder






106a




curved inner surface of wedge member 106







accommodating drill pipe






106b




curved inner surface of wedge member 106







accommodating enlarged diameter section 21






107




tapered outer face of wedge members 106






108




hinges connecting wedge members






109




tapered shoulder of wedge members 106






111




connectors between wedge members 106 and lifting







arms 112






112




lifting arms for lifting wedge members 106






114




actuator for moving lifting arm 112






115




lifting eye on wedge member 106






200




upper holder






203




opening in main body of upper holder






204




main body of upper holder






205




tapered inner face of main body 204






206




wedge members of upper holder






206a




curved inner surface of wedge member 206







accommodating drill pipe






206b




curved inner surface of wedge member 206







accommodating end of drill pipe






207




tapered outer face of wedge member 206






209




tapered shoulder of wedge member 206






210




elevator links






211




connectors between wedge member 206 and lifting







arms 212






212




lifting arm for lifting wedge member 206






213




lifting eyes






214




actuator for moving lifting arm 212






215




lifting eye on wedge member 206






220




recessed area of upper holder






221




eye of elevator link






222




elevator link retainer






224




release pin






225




hinge






230




lifting eyes to support auxiliary upper holder






300




auxiliary upper holder






301




connectors for auxiliary holder 300






304




main body of holder 300














The following table lists and describes the dimensions used herein and in the drawings attached hereto:















DIMENSION LIST






DIMENSION DESCRIPTION

















E.O.D.




end outside diameter of pin end and box end of








drill pipe







E.W.T.




end wall thickness of pin end and box end of








drill pipe







P.I.D.




pipe inside diameter







P.W.T.




pipe wall thickness







P.O.D.




pipe outside diameter







E.D.W.T.




enlarged diameter wall thickness







R.W.H.




reasonable working height of box end above rig








floor







L




length of drill pipe







D




distance between supporting shoulders







A




angle of shoulder taper







LE




length of enlarged diameter section







T-1




top thickness of the wedge member







T-2




thickness of the wedge member at the shoulder







T-3




bottom thickness of the wedge member







H-1




height of the wedge member







H-2




vertical height of the shoulder of the wedge








member







H-3




distance between the bottom of the wedge member








and the bottom of the shoulder







A.T.




Angle of taper of the outer face of the wedge








member







A.T.-2




Angle of taper of the second tapered outer face








of the wedge member in the preferred embodiment







H.H.




Height of upper holder







W-1




width of upper holder







W-2




width of top of opening of upper holder







W-3




width of bottom of opening of upper holder















The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims.



Claims
  • 1. A method of landing items at a well location, comprising the steps of:a) positioning a drilling rig above a well location, the drilling rig having a landing string that is comprised of a number of joints of drill pipe that generate a huge tensile load, and a holder that holds a joint of drill pipe in the landing string for supporting the landing string; b) attaching an item to the lower end of the landing string and lowering the landing string such that it spans the distance between the drilling rig and the well location; c) wherein the holder, and the joint of drill pipe that is held by the holder, are configured to support the tensile load of the landing string with correspondingly shaped shoulders that engage when the holder holds the joint of drill pipe; and d) wherein the shoulders are rotatable with respect to each other, regardless of the distance between said shoulders.
  • 2. The method of claim 1 wherein in steps “a” and “c” the holder does not have teeth.
  • 3. The method of claim 1 wherein in steps “a” and “c” the holder does not have projecting structure that bites into and deforms the surface of the drill pipe.
  • 4. The method of claim 1 wherein in steps “a” and “c” the holder includes a main body and a plurality of wedge members, the wedge members forming an interface between the body and the joint of drill pipe being held by the holder.
  • 5. The method of claim 4 wherein at least one wedge member is movable between pipe engaged and pipe disengaged positions through the use of a lifting arm which is attached at one end to the holder and is attached at another end to said movable wedge member.
  • 6. The method of claim 5 further comprising the step of powering the movable wedge member through the use of an actuator which is attached at one end to the lifting arm and is attached at another end to the holder.
  • 7. The method of claim 5 wherein said movable wedge member includes at least one recess which accommodates the end of the lifting arm which is attached to said movable wedge member.
  • 8. The method of claim 7 wherein the end of the lifting arm which is attached to said movable wedge member is slotted, and wherein said slotted end of said lifting arm is connected to said movable wedge member through the use of a pin member which extends into said slotted end.
  • 9. The method of claim 8 wherein the pin member locates in the slotted end of the lifting arm closest to the drill pipe when the wedge member is in the pipe engaged position.
  • 10. The method of claim 8 wherein the pin member locates in the slotted end of the lifting arm furthest from the drill pipe when the wedge member is in the pipe disengaged position.
  • 11. The method of claim 1 wherein in steps “a” and “c” the holder includes a main body and a plurality of wedge members, the wedge members forming an interface between the body and the joint of drill pipe being held by the holder, each wedge member having a shoulder, the shoulders of the wedge members engaging the shoulder of the drill pipe being held by the holder.
  • 12. The method of claim 1 wherein in steps “a” and “c” each joint of drill pipe has a pin end and a box end and an enlarged diameter section, and wherein the enlarged diameter section is spaced between one and eight feet from the box or pin ends.
  • 13. The method of claim 12 wherein in steps “a” and “c” at least one of the ends of the drill pipe and the enlarged diameter section have correspondingly shaped shoulders.
  • 14. The method of claim 13 wherein in steps “a” and “c” each joint of pipe has a weight of between about 29 and 110 pounds per linear foot.
  • 15. The method of claim 1 wherein in steps “a” and “c” each joint of pipe has pin and box end portions, each with a shoulder, and the enlarged diameter section is positioned between about one and eight feet from the box and pin end portions.
  • 16. The method of claim 1 further comprising the step of lowering a conduit along with and on the outside of the drill pipe.
  • 17. The method of claim 16 wherein the holder includes a groove which is sized to permit the conduit to pass therethrough, without being damaged, as the conduit is lowered.
  • 18. A method of well casing placement comprising the steps of:a) positioning a drilling rig above a well location, the drilling rig having a landing string that is comprised of a number of joints of drill pipe that generate a huge tensile load, and a holder that holds a joint of drill pipe in the landing string for supporting the landing string; b) lowering a plurality of connected joints of casing to the well, said plurality of connected joints of casing defining a casing string, the casing string being supported by the landing string; c) configuring the combination of landing string and casing string so that the overall combined length of the landing string and casing string spans the distance between the drilling rig and the well location, and wherein the combined weight of landing string and casing string is between about 950,000 and 2,300,000 pounds; d) wherein the holder, and the joint of drill pipe that is held by the holder, are configured to support the tensile load of step “c” with correspondingly shaped frustoconical shoulders that engage when the holder holds the joint of drill pipe.
  • 19. The method of claim 18 wherein in steps “a” and “d” the holder includes a main body and a plurality of wedge members, the wedge members forming an interface between the body and the joint of drill pipe being held by the holder.
  • 20. The method of claim 18 wherein in steps “a” and “d” the holder includes a main body, and a plurality of wedge members, the wedge members forming an interface between the body and the joint of drill pipe being held by the holder, each wedge member having a shoulder, the shoulders of the wedge members engaging the shoulder of the drill pipe being held by the holder.
  • 21. The method of claim 20 wherein in steps “a” and “d” each joint of drill pipe has a pin end and a box end and an enlarged diameter section, and wherein the enlarged diameter section is spaced between one and eight feet from the box or pin ends.
  • 22. The method of claim 21 wherein in steps “a” and “d” at least one of the ends of the drill pipe and the enlarged diameter section have correspondingly shaped frustoconical shoulders.
  • 23. The method of claim 18 wherein in steps “a”, “c” and “d” each joint of pipe has a weight of between about 29 and 110 pounds per linear foot.
  • 24. The method of claim 18 wherein in steps “a” and “d” each joint of pipe has pin and box end portions, each with a shoulder, and an enlarged diameter section that is positioned between about one and eight feet from the box and pin end portions.
  • 25. The method of claim 24 wherein in steps “a” and “d” the shoulder forms an angle of between 10 and 45 degrees with the central longitudinal axis of its joint of pipe.
  • 26. The method of claim 18 wherein in steps “a” and “d” each joint of pipe has pin and box end portions, each with a shoulder, and an enlarged diameter section that is positioned between about two and three feet from the box and pin end portions.
  • 27. The method of claim 26 wherein in steps “a” and “d” the shoulder forms an angle of between 10 and 45 degrees with the central longitudinal axis of its joint of pipe.
  • 28. A method of landing casing string for use in water depths of at least 300 hundred feet, comprising the steps of:a) positioning a drilling rig above an undersea well location, the drilling rig having a landing string that is comprised of a number of joints of drill pipe that generate a huge tensile load, and a holder for supporting the landing string when one or more pipe joints is to be added to or removed from the landing string; b) lowering a plurality of connected joints of casing to the undersea well, said plurality of connected joints of casing defining a casing string, wherein the landing string in step “a” has upper and lower end portions, the casing string being supported by the lower end portion of the landing string; c) configuring the combination of landing string and casing string so that the overall, combined length of the landing string and casing string spans at least a majority of the distance between the drilling rig and the undersea well location at the seabed, and wherein the combined weight of landing string and casing string is between about 950,000 and 2,300,000 pounds; d) wherein the holder and an uppermost joint of drill pipe that is supported by the holder, are configured to support the load of step “c” at a load transfer interface that includes correspondingly shaped respective shoulders of the drill pipe and holder that are surfaces each defined by rotating a line 360° about a central axis.
  • 29. The method of claim 28 wherein in step “a” the pipe joints each have a weight of at least 29 pounds per foot.
  • 30. The method of claim 28 wherein in steps “a” and “d” the holder does not have teeth that bite into and deform the surface of the drill pipe.
  • 31. The method of claim 28 wherein in steps “a” and “d” the holder includes a main body and a plurality of wedge members movably connectable to the main body, the wedge members forming an interface between the body and the uppermost joint of drill pipe.
  • 32. The method of claim 31 wherein the wedge members are movable between pipe engaging and released positions, and further comprising the step of powering the wedge members to move using pressurized fluid.
  • 33. The method of claim 28 wherein in steps “a” and “d” the holder includes a main body and a plurality of wedge members that form an interface between the body and the uppermost joint of drill pipe, each wedge member and the holder having an annular tapered shoulder, the tapered shoulders of the wedge members engaging the tapered annular shoulder of the main body when supporting the landing string.
  • 34. The method of claim 28 wherein each pipe joint has a pin end portion and a box end portion and an annular enlarged diameter section spaced between one and three feet from one of the box or pin end portions.
  • 35. The method of claim 34 wherein at least one of the one end portions and the annular enlarged diameter section have correspondingly shaped tapered shoulders.
  • 36. The method of claim 35 wherein each joint of pipe has a weight of between about 29 and 110 pounds per linear foot.
  • 37. The method of claim 34 wherein each joint of pipe has pin and box end portions, each with a tapered annular shoulder, and the annular enlarged diameter section is positioned between about one and six feet from the box end portion.
  • 38. The method of claim 28 wherein the casing string is comprised of joints of casing and wherein each joint of casing has a weight of between about 40 to 80 pounds per linear foot.
  • 39. The method of claim 28, further comprising the step of separating the holder from an engaged position with the landing string before step “c”.
  • 40. The method of claim 28 further comprising the step of powering the holder with pressurized fluid.
  • 41. The method of claim 28 wherein step “b” comprises in part lowering a casing string that weights at least 600,000 pounds.
  • 42. The method of claim 28 wherein step “b” comprises in part lowering a casing string that is between 15,000 and 20,000 feet in length.
  • 43. The method of claim 28 wherein step “a” further comprises maintaining the drilling rig above the undersea well location without the use of anchors or anchor lines.
  • 44. The method of claim 28 wherein in step “c” the casing string includes a plurality of joints that each have a maximum diameter that is greater than the maximum diameter of a plurality of the joints of the landing string.
  • 45. The method of claim 28 wherein the plurality of joints of casing include joints of casing of differing diameters.
  • 46. A method of deep sea well casing placement for use in water depths of at least 300 hundred feet, comprising the steps of:a) positioning a drilling rig above an undersea well location, the drilling rig having a landing string that is comprised of a number of joints of drill pipe that general a huge tensile load, and a holder for supporting the landing string when one or more pipe joints is to be added to or removed from the landing string, each joint of drill pipe having a central longitudinal axis; b) lowering a plurality of connected joints of casing to the undersea well, said plurality of connected joints of casing defining a casing string, wherein the landing string in step “a” has upper and lower end portions, the casing string being supported by the lower end portion of the landing string; c) configuring the combination of landing string and casing string so that the overall, combined length of the landing string and casing string spans the distance between the drilling rig and the undersea well location at the seabed, and wherein the combined weight of landing string and casing string is between about 950,000 and 2,300,000 pounds; d) wherein the holder, and an uppermost joint of drill pipe that is supported by the holder, are configured to support the tensile load of step “c” with correspondingly shaped tapered shoulders that engage when the holder supports the uppermost joint of drill pipe, said shoulders being surfaces defined by rotating a line 360° about the drill pipe central longitudinal axis.
  • 47. The method of claim 46 wherein the holder includes a main body, and a plurality of wedge members that form an interface between the body and the uppermost joint of drill pipe.
  • 48. The method of claim 47 wherein the wedge members are movable between pipe engaging and released positions, and further comprising the step of powering the wedge members to move using pressurized fluid.
  • 49. The method of claim 46 wherein the holder includes a main body, and a plurality of wedge members that form an interface between the body and the uppermost joint of drill pipe, each wedge member and the holder having an annular tapered shoulder, the tapered shoulders of the wedge members engaging the tapered annular shoulder of the main body when supporting the landing string.
  • 50. The method of claim 49 wherein each pipe joint has a pin end portion and a box end portion and an annular enlarged diameter section spaced between one and ten feet from one of the box or pin end portions.
  • 51. The method of claim 50 wherein at least one of the one end portions and the annular enlarged diameter section have correspondingly shaped annular tapered shoulders.
  • 52. The method of claim 46 wherein each joint of pipe has a weight of between about 29 and 110 pounds per linear foot.
  • 53. The method of claim 46 wherein in step “a” each joint of pipe has pin and box end portions, each with a tapered annular shoulder, and the annular enlarged diameter section is positioned between about one and six feet from the box end portion.
  • 54. The method of claim 53 wherein in step “a” the tapered annular shoulder forms an angle of between 10 and 45 degrees with the central longitudinal axis of its joint of pipe.
  • 55. The method of claim 46 wherein in step “a” each joint of pipe has pin and box end portions, each with a tapered annular shoulder, and the annular enlarged diameter portion is positioned between about two and three feet from the box end portion.
  • 56. The method of claim 55 wherein the tapered annular shoulder forms an angle of between 10 and 45 degrees with the central longitudinal axis of its joint of pipe.
  • 57. The method of claim 46 wherein the casing string is comprised of joints of casing and wherein each joint of casing has a weight of between about 40 to 80 pounds per linear foot.
  • 58. The method of claim 46, further comprising the step of separating the holder from an engaged position with the landing string before step “c”.
  • 59. The method of claim 46 further comprising the step of powering the holder with pressurized fluid.
  • 60. The method of claim 46 wherein step “b” comprises in part lowering a casing string that weights at least 600,000 pounds.
  • 61. The method of claim 46 wherein step “a” further comprises maintaining the drilling rig above the undersea well location without the use of anchors or anchor lines.
  • 62. The method of claim 46 wherein in step “c” the casing string includes a plurality of joints that each have a maximum diameter that is greater than the maximum diameter of a plurality of the joints of the landing string.
  • 63. The method of claim 46 wherein the plurality of joints of casing include joints of casing of differing diameters.
  • 64. A method of well casing placement comprising the steps of:a) positioning a drilling rig above an undersea well location, the drilling rig having a lifting device, a landing string that is comprised of a number of joints of drill pipe that generate a huge tensile load, and a holder for supporting the landing string when one or more pipe joints is to be added to or removed from the landing string, each joint of drill pipe having a central longitudinal axis; b) supporting the landing string with the lifting device; c) lowering a plurality of connected joints of casing to the undersea well, said plurality of connected joints of casing defining a casing string, wherein the landing string in step “a” has upper and lower end portions, the casing string being supported by the lower end portion of the landing string; d) configuring the combination of landing string and casing string so that the overall, combined length of the landing string and casing string spans at least a majority of the distance between the drilling rig and the undersea well location at the seabed, and wherein the combined weight of landing string and casing string is between about 950,000 and 2,300,000 pounds; e) wherein the holder, and an uppermost joint of drill pipe that is supported by the holder, are configured to support the tensile load of step “d” with a first shoulder on the holder and a second shoulder on the uppermost joint of drill pipe, each shoulder being configured to enable loading of one shoulder upon the other in positions that do not require alignment of the holder and uppermost joint of drill pipe just prior to loading.
  • 65. The method of claim 64 wherein the casing string is comprised of joints of casing and wherein each joint of casing has a weight of between about 40 to 80 pounds per linear foot.
  • 66. The method of claim 64, further comprising the step of separating the holder from an engaged position with the landing string before step “c”.
  • 67. The method of claim 64 further comprising the step of powering the holder with pressurized fluid.
  • 68. The method of claim 64 wherein step “b” comprises in part lowering a casing string that weights at least 600,000 pounds.
  • 69. The method of claim 64 wherein in step “c” the casing string includes a plurality of joints that each have a maximum diameter that is greater than the maximum diameter of a plurality of the joints of the landing string.
  • 70. The method of claim 64 wherein the plurality of joints of casing include joints of casing of differing diameters.
  • 71. A drilling rig, pipe and pipe handling apparatus, comprising:a) a drilling rig with a floor; b) a landing string comprised of a number of joints of pipe connected end to end and that generates a huge tensile load at the floor, at least a plurality of the joints of pipe having an enlarged diameter section with a shoulder that is spaced apart from either end of the pipe; c) first and second holders that provide support for the tensile loaded landing string; d) wherein the first holder is a lower holder positioned near the rig floor that holds a joint of pipe of the landing string and supports the landing string during the addition or removal of a joint of pipe to or from the landing string, and the second holder is an upper holder that holds a joint of pipe in the landing string and supports the landing string after a joint of pipe has been added to or removed from the landing string; e) each of the holders including a main body and a plurality of wedge members, the wedge members forming an interface between the body and the joint of pipe being held by the holder, each wedge member having a shoulder that corresponds in shape to and engages with the shoulder at the enlarged diameter section of the joint of pipe being held by one of the holders; and f) wherein the shoulders are rotatable with respect to each other, regardless of the distance between said shoulders.
  • 72. A pipe and pipe handling apparatus comprising:a) a landing string comprised of a number of joints of pipe connected end to end that generate a huge tensile load, each joint of pipe having generally cylindrically shaped pin and box end portions, a generally cylindrically shaped smaller diameter portion that extends over a majority of the length of each joint, and an enlarged diameter generally cylindrically shaped section spaced in between the pin and box end portions; b) a pair of vertically spaced apart pipe holders that each enable the landing string to be supported; c) wherein the holders and each joint of pipe of the landing string are configured to support the tensile load of the landing string with correspondingly shaped frustoconical shoulders that engage when one of the holders holds a joint of pipe of the landing string; and d) each holder including a main body and a plurality of wedge members, the wedge members forming an interface between the body and the joint of pipe being held by the holder.
  • 73. A pipe and pipe handling apparatus comprising:a) a landing string comprised of a number of joints of pipe connected end to end that generate a huge tensile load, each joint of pipe having generally cylindrically shaped pin and box end portions, a generally cylindrically shaped smaller diameter portion that extends over a majority of the length of each joint, a generally cylindrically shaped enlarged diameter section spaced in between the pin and box end portions, and a central longitudinal axis; b) a pair of vertically spaced apart pipe holders that each enable the landing string to be supported; c) wherein each holder and a joint of pipe of the landing string that is held by the holder are configured to support the tensile load of the landing string with correspondingly shaped shoulders that engage when the holder holds the joint of pipe, said shoulders being surfaces defined by rotating a line 360° about the drill pipe central longitudinal axis; and d) each holder including a main body, a plurality of wedges that are movable between engaged and disengaged positions, said wedges defining an interface between the body and the joint of pipe being held by the holder, and wherein one of the holders has a body that is movable in a vertical direction during use.
  • 74. A drilling rig, pipe, and pipe support apparatus, comprising:a) a drilling rig having a floor; b) a landing string comprised of a number of joints of drill pipe connected end to end, extending from the rig, that generate a huge tensile load at the floor; c) a drill pipe holder, located at the rig floor, that holds a joint of drill pipe of the landing string and supports the landing string during the addition or removal of a joint of drill pipe to or from the landing string; d) wherein the holder and the joint of drill pipe that is held by the holder are configured to support the tensile load of the landing string with correspondingly shaped shoulders that engage when the holder holds the joint of drill pipe; e) the holder including a main body and a plurality of wedge members, the wedge members forming an interface between the body and the joint of drill pipe being held by the holder; and f) wherein the shoulders are rotatable with respect to each other, regardless of the distance between said shoulders.
  • 75. A pipe and pipe support apparatus comprising:a) a landing string comprised of a number of joints of pipe connected end to end that generate a huge tensile load, each joint of pipe having pin and box end portions and an enlarged diameter section spaced in between the pin and box end, but closer to the box end portion; b) a pipe holder that holds a joint of pipe of the landing string and supports the landing string at the enlarged diameter section during the addition or removal of a joint of pipe to or from the landing string; c) wherein the holder and the joint of pipe that is held by the holder are configured to support the tensile load of the landing string with correspondingly shaped frustoconical shoulders that engage when the holder holds the joint of pipe; and d) the holder including a main body and a plurality of wedge members, the wedge members forming an interface between the body and the joint of pipe being held by the holder.
  • 76. A pipe and pipe support apparatus comprising:a) a landing string comprised of a number of joints of pipe connected end to end that generate a huge tensile load, each joint of pipe having enlarged diameter pin and box end portions and an enlarged diameter section spaced in between the pin and box end portions, but closer to the box end portion, each joint of pipe also having a central longitudinal axis; b) a pipe holder that supports the landing string at the enlarged diameter section during the addition or removal of a joint of pipe to or from the landing string; c) wherein the holder and an uppermost joint of pipe that is supported by the holder are configured to support the tensile load of the landing string with correspondingly shaped shoulders that engage when the holder supports the uppermost joint of pipe, said shoulders being surfaces defined by rotating a line 360° about the drill pipe central longitudinal axis; and d) the holder including a main body, and a plurality of wedge members that form an interface between the body and the uppermost joint of pipe.
  • 77. A pipe and pipe support apparatus comprising:a) a landing string comprised of a number of joints of pipe connected end to end that generate a huge tensile load, wherein a number of joints of the pipe in the landing string have an enlarged diameter section and wherein the enlarged diameter section is spaced apart from the ends of the pipe, but closer to one end than the other; b) a pipe holder that supports the enlarged diameter section of pipe in the landing string during the addition or removal of a joint of pipe to or from the landing string; c) wherein the holder and the joint of pipe that is held by the holder are configured to support the tensile load of the landing string with corresponding shoulders that engage when the holder holds the joint of pipe; d) the holder including a main body and a plurality of wedge members, the wedge member forming an interface between the body and the joint of pipe being held by the holder; and e) wherein no specific radial alignment of the corresponding shoulders is necessary prior to or during their engagement.
CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation-in-part of U.S. patent application Ser. No. 09/586,239, filed Jun. 2, 2000, now U.S. Pat. No. 6,378,614, issued Apr. 30, 2002, which is incorporated herein by reference. The present application pertains to subject matter which is related to two other patent applications including U.S. Ser. No. 09/586,232, filed Jun. 2, 2000 and entitled “Drilling Rig, Pipe and Support Apparatus”, now U.S. Pat. No. 6,349,764, issued Feb. 26, 2002, and U.S. Ser. No. 09/586,233, filed Jun. 2, 2000 and entitled “Drill Pipe Handling Apparatus”, now U.S. Pat. No. 6,364,012, issued Apr. 2, 2002, each hereby incorporated herein by reference.

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3629927 Palmer et al. Dec 1971 A
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5732909 Sonnier Mar 1998 A
5992801 Torres Nov 1999 A
6047781 Scott et al. Apr 2000 A
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Entry
S. T. Horton, “Drill String and Dril Collars,” Rotary Drilling Series of Instructional Texts, Unit I, Lesson 3, First Edition, 1995 (more than 4 years earlier than effective filing date of captioned application), pp. 0-105 (entire book) published by Petroleum Extension Service, Division of Continuing Education, The University of Texas at Austin, in cooperation with International Association of Drilling Contractors.
L.D. Davis, “Rotary, Kelly, Swivel, Tongs, And Top Drive,” Rotary Drilling Series of Instructional Texts, Unit I, Lesson 4, First Edition, 1995 (more than 4 years earlier than effective filing date of captioned application), pp. 27-39 and 48-62 published by Petroleum Extension Service, Division of Continuing Education, The University of Texas at Austin, in cooperation with International Association of Drilling Contractors.
L.D. Davis, “The Blocks and Drilling Line,” Rotary Drilling Series of Instructional Texts, Unit I, Lesson 5, Third Edition, 1996 (more than 3 years earlier than effective filing date of captioned application), pp. 1-2 and 89-92, published by Petroleum Extension Service, Division of Continuing Education, The University of Texas at Austin, in cooperation with International Association of Drilling Contractors.
Tom H. Hill, letter (2 pages) to Mr. Burt Adams dated Aug. 20, 2001, with 4 pages of attached drawings.
A.T. Bourgoyne, Jr., et al., “Applied Drilling Engineering,” 1991 (more than 9 years earlier than the effective filing date of the captioned application), vol. 2, p. 19, published by Society of Petroleum Engineers.
Continuation in Parts (1)
Number Date Country
Parent 09/586239 Jun 2000 US
Child 10/055005 US