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Publication numberUS3561616 A
Publication typeGrant
Publication dateFeb 9, 1971
Filing dateJul 29, 1969
Priority dateJul 29, 1969
Publication numberUS 3561616 A, US 3561616A, US-A-3561616, US3561616 A, US3561616A
InventorsEddy Kenneth H, Mcgill Kenneth H
Original AssigneeDresser Ind
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Well drilling apparatus
US 3561616 A
Abstract  available in
Images(4)
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Claims  available in
Description  (OCR text may contain errors)

United States Patent [72] inventors Kenneth H. Eddy Jefferson County, Tex.; Kenneth H. McGill, Jefferson County, Tex. [21] Appl. No. 845,758 [22] Filed July 29, 1969 [45] Patented Feb. 9, 1971 [73] Assignee Dresser Industries, Inc.

Dallas, Tex. a corporation of Delaware [54] WELL DRILLING APPARATUS 9 Claims, 8 Drawing Figs.

[52] US. Cl 2l4/2.5, 175/85 [51] lnt.Cl ..E21b 19/14 [50] Field of Search 214/25; 175/85 [56] References Cited UNITED STATES PATENTS 3,443,647 5/1969 Jenkins et al. l75/85 3,451,493 6/1969 Storm Primary Examiner-Gerald M. Forlenza Assistant Examiner-Frank E. Werner AttorneysRobert W. Mayer, Danie] Rubin, Roy L.

VanWinkle, William E. Johnson Jr. and Roderick W. MacDonald ABSTRACT: The well drilling apparatus described herein includes a drilling mast pivotally mounted on a base, a separate pipe racking mast mounted on the lbase, and drill pipe transfer means extending between the drilling mast and pipe racking mast. The drilling mast of the apparatus can be tilted at an angle relative to the pipe racking mast which is disposed substantially vertically. The transfer means includes a track extending between the pipe racking mast and the drilling mast and a trolley moveable on the track for moving the drill pipe from the racking mast to the drilling mast and vice versa. Pipe engaging means located on the lower end of the drilling mast is provided to engage the lower end of the drill pipe so that the lower end of the drill pipe is retained on the well bore axis during at least a portion of the movement between the masts.

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WELL DRILLING APPARATUS BACKGROUND OF THE INVENTION This invention relates generally to well drilling apparatus. More particularly, but not by way of limitation, this invention relates to well drilling apparatus for drilling slant holes.

In slant hole drilling rigs constructed in the past, several problem have been encountered. For example, none have provided a satisfactory method of restraining the lower end of the drill pipe in alignment with the well bore during the process of adding or removing sections of the pipe. In fact, most such apparatus have included relatively massive equipment for the purpose of handling only single joints of the pipe and with which the entire joint is restrained.

In such apparatus, it is necessary when making a trip, that is removing the entire drill string to replace the bit, to disconnect each joint of pipe (A joint is approximately 30 feet long.) and to lay the disconnected pipe sections or joints on a horizontal pipe rack. Such a method is extremely expensive and time consuming and, in addition, has the disadvantage that every threaded connection in the drill string must be broken each time a trip is made. I

In the invention herein disclosed, the drill pipe can be handled in stands, that is, in units consisting of two or more 30 foot joints of the drill pipe. The stands are racked vertically in the separate pipe racking mast so that it is not necessary to lay the pipe down during a trip. Also, utilizing stands of drill pipe eliminates the necessity for disconnecting each threaded joint and therefore saves considerable time and reduces the wear on the drill pipe.

One object of this invention is to provide an improved slant hole drilling apparatus wherein trips into and out of the well bore can be made more quickly.

Another object of the invention is to provide an improved slant hole drilling apparatus incorporating means for retaining the lower end of the drill pipe accurately on the well bore axis during making up and breaking of threaded joints between the stands of drill pipe.

Still another object of the invention is to provide an improved drilling apparatus wherein the drill pipe is handled in stands during trips and the stands of pipe are safely, quickly and efficiently moved between the drilling mast and pipe racking mast.

SUMMARY OF THE INVENTION This invention provides improved well drilling apparatus utilizing drill pipe to position a drill bit on the bottom of a well bore, the apparatus comprising: a substantially vertical pipe racking mast for storing multiple sections or stands of drill pipe in a substantially vertical position; a tiltable drilling mast spaced from the pipe racking mast, the drilling mast including crown block mounted on the upper end thereof, a traveling block moveable in the drilling mast, and guide means for limiting the movement of the traveling block whereby its movement coincides with the axis of the well bore; and, drill pipe transfer means for moving the stands of drill pipe between the pipe racking mast and the drilling mast, the transfer means including pipe engaging means mounted on the drilling mast for positioning the lower end of the drill pipe on the well bore axis during movement of the drill pipe from the racking mast to the drilling mast.

The foregoing and additional objects and advantages of the invention will become more apparent as the following detailed description is read in conjunction with the accompanying drawings wherein like reference characters denote like parts in all views.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is an elevation view of well drilling apparatus constructed in accordance with the invention and shown with the drilling mast in a substantially vertical position.

FIG. 2 is a view similar to FIG. I, but showing the drilling mast in a tilted position.

FIG. 3 is an enlarged, partial plan view illustrating the pipe racking structure and the trolley/track arrangement.

FIG. 4 is an enlarged cross-sectional view taken along line 4-4 of FIG. 3.

FIG. 5 is an enlarged cross-sectional view of pipe supporting means located on the trolley shown in FIG. 4.

FIG. 6 is a cross-sectional view taken along line 6-6 of FIG. 5.

FIG. 7 is a schematic view-illustrating another embodiment of the invention.

FIG. 8 is a schematic view similar to FIG. 7, but illustrating still another embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing and to FIGS. 1 and 2 in particular, shown therein is a drilling apparatus constructed in accordance with the invention and designated generally by the reference character 10. The drilling apparatus 10 includes a vertically disposed pipe racking mas-t I2 that is mounted on a base 14. The drilling apparatus 10 also includes a drilling mast 16 that is pivotally supported by the base 14. A track I8 is connected to the upper end of the pipe racking mast I2 and is arranged to extend between the pipe racking mast I2 and the drilling mast 16.

The pipe racking mast I2 includes, near its upper end, a pipe racking platform 20. As shown more clearly in FIG. 3, the pipe racking platform 20 includes a plurality of fingers or tines 22 that extend outwardly toward the drilling mast I6. The fingers 22 are provided for the purpose of guiding and locating the plurality of stands 24 of drill pipe that are frequently racked therein. The lower ends (not shown) of the pipe stands 24 are situated directly below the pipe racking platform 20 on the base 14 in an area generally referred to as the setback and designated by the reference character 26. The racking platform 20 is arranged in the pipe racking mast 12 a sufiicient distance above the setback 26 to accommodate the desired length of the drill pipe stands 24 being utilized.

The drilling mast 16 includes a generally semicircular mounting assembly 28 that is received in a suitable cradle 30 that is mounted on the base 14. The arrangement between the mounting assembly 28 and the cradle 30 is such that the drilling mast I6 can be tilted to the desired angle for drilling.

Positioned in the lower end of the drilling mast I6 is a rotary table 32. Traveling block guide means 34 extends upwardly along the side of the drilling mast l6 opposite the pipe racking mast l2 and is operably connected with the traveling block 36 and elevator 38 so that the traveling block 36 and elevator 38 are moved along the drilling mast 16 in a line corresponding to the axis of the well bore (not shown).

Mounted on the upper end of the drilling mast 16 is a crown block assembly 40 that is connected with the traveling block 36 by a plurality of lines or cables 42. A drawworks or hoisting mechanism 44 is mounted in the base 14. The cable 42, after being appropriately strung through the traveling block 36 and crown block 40, extends downwardly to the hoisting mechanism 44 so that the traveling block 36 can be traversed throughout the length of the drilling mast l6.

Mast support struts 46 extend from pivotal connections with the drilling mast 16 to a positioning rails 48 located on the base 14. The positioning rails 48 are provided with a plurality of holes for receiving pins connecting the mast support struts 46 with the positioning rails 48 at any selected position thereon. It will be noted in FIG. 1 that the mast support struts 46 are pinned to the uppermost portion of the positioning rails 48 when the drilling mast 16 is in the vertical position. FIG. 2 illustrates the drilling mast 16 in a tilted position and the mast support struts 46 are located in the lowermost hole of the positioning rails 48.

To position the drilling mast 16 at the desired angle, there is provided one or more hydraulic actuators 50 that are pivotally connected with the drilling mast l6 and. with the base 14. As can be appreciated by comparing FIGS. 1 and 2, the angular or tilted position of the drilling mast 16 can be varied by extending and contracting the hydraulic actuator 56.

A pipe engaging member 52 is mounted in the lower end of the drilling mast R6. The pipe engaging member 52 may be of any suitable configuration that will receive and support the lower end of the pipe stands M on the axis of the well bore.

Mounted on the drilling mast 16 are suitable track support members 54. The track support members 54 are arranged to engage and support the track I3 regardless of the angular position of the drilling mast 16.

As shown in FIG. 3, the track 18 includes a pair of spaced track members 56 and 58 that are located on opposite sides of the drilling mast 16 in the preferred form of the invention. When using the two track members 56 and 58 as illustrated, it will of course be necessary to provide a track support member 54 for each of the track members 56 and 58.

Each of the track members 56 and 58 is provided with an arcuate portion that curves downwardly toward the free ends of the track members 56 and S8. The are or curvature of the members 56 and 58 is defined by the locus of a point moving at a fixed distance from the pivot axis of the drilling mast 16.

As previously mentioned, the track I8 is connected at one end with the pipe racking mast l2 and as can be seen in FIG. 3, the track members 56 and 58 are spaced sufficiently far apart so as to be disposed on either side of the pipe racking platform whereby all of the pipe stands 24 are racked therebetween.

A trolley assembly 60 is mounted for movement along the track 18 between the pipe racking mast l2 and the drilling mast 16. As will be described in detail hereinafter, the trolley assembly 60 is constructed to transport the pipe stands 24 between the pipe racking mast 12 and the drilling mast 16 regardless of the angular position of the drilling mast 16. As desired, the trolley 60 may either be self-propelled or moved along the track 18 by an external power source.

The trolley assembly 60 includes a traveling bridge 62 that extends between the track members 56 and 58. The traveling bridge 62 is provided with wheels 64 whereby the traveling bridge 6; can move along the track 18.

Spaced, parallel rails 66 extend across the traveling bridge 62 to support a carriage 68 that is provided with wheels 70 that are engaged with the rails 66. The carriage 68 moves across the traveling bridge 62 in a direction perpendicular to the track 18.

A pipe support assembly 72 is carried by the trolley assembly 60. The pipe support assembly 72 is rotatably mounted on the carriage 68 and includes an eccentric depending leg 74. Mounted for vertical movement along the leg 74 is a transfer elevator 76.

The cross-sectional views of FIGS. 5 and 6 illustrate the transfer elevator 76 and its associated mechanism in more detail. As shown therein, the a generally U-shaped pipe support member 78 is provided for the purpose of actually engaging and supporting the pipe stands 24.

An elongated portion 863 of the support member 78 extends into a hollow elevator housing 82. The support member 78 is pivotally mounted on the housing 82 by a pin 84 that extends through the elongated portion 80 and the housing 82.

Upper and lower springs 66 and 88 are disposed within the housing 82. The springs 86 and 88 are located on opposed sides of the elongated portion 80 of the support member 78 and are arranged to resiliently retain the support member 78 in the position illustrated in FIG. 5.

As can be seen more clearly in FIG. 6, the leg 74 is a hollow, elongated member having an open side to receive a portion of the housing 32. Disposed within the leg 74 are a plurality of wheels N) that moveably support the housing 82 for movement along the leg 74. Although not shown, the transfer elevator 76 includes means for moving the elevator vertically within the leg 74. The motive means may be either self-contained or may be a hoist-type device located externally of the transfer elevator 76.

OPERATION OF THE PREFERRED EMBODIMENT When the apparatus 10 is utilized for drilling a slanted well bore, the drilling mast I6 is tilted as illustrated in FIG. 2. As shown therein, the hydraulic actuator has tilted the mast about the mounting assembly 28 and cradle 30. The strut 46 is positioned in the lower holes in the positioning rail 48 to. securely support the drilling mast 16 in the tilted position.

If the drill pipe is to be removed from the well bore, the traveling block 36 and elevator 38 are lowered until the eleva tor 38 engages the upper end of the drill pipe which is located at this time, near the lower end of the drilling mast 16 that is, just above the rotary table 32. The traveling block 36 and elevator 38 are then raised in the drilling mast 16 until the upper end of the drilling string is approximately even with the track 18. The trolley assembly is then moved to the. position illustrated in FIG. 2 and transfer elevator 76engaged with the drill pipe as the threaded connection at the rotary table 32 is broken.

As soon as the connection is broken, the trolleyassembly 60 is moved across the track I8 toward the racking mast I2. During the traverse of the trolley assembly 60 and until the stand 24 of drill pipe, which has been broken from the drill string, reaches the vertical position, the lower end ofthe stand 24 rests against the pipe engaging member 52.

Farther movement of the trolley assembly 60 along the horizontal portion of the track l8 then moves the pipe stand 24 into the pipe racking platform 20. The pipe support as-- sembly 72, which includes the transfer elevator 76, is rotated to position the stand 24 in alignment with one of the slots between the tines 22 wherein the pipe stand 24 is to be racked.

If necessary, the carriage 68 can be moved across are traveling bridge 62 to permit the transfer elevator 76 to position the pipe stand 24 in the proper slot. In any event, the transfer elevator 76 is lowered, when the stand 24 is properly positioned in the platform 20, to set the lower end of the stand 24 on the setback 26.

As the trolley assembly 60 is transferring the stand 24 fromthe drilling mast 16 to the racking mast 12, the traveling block 36 and elevator 38 are being lowered into engagement with the upper end of the pipe string located adjacent to the rotary table 32. The traveling block 36 is then raised in the drilling mast I6 lifting the upper end of the drill pipe until it again reaches the proper position for engagement with'the trolley" assembly 60.

Simultaneously with the foregoing, the trolley assembly 60, after depositing the stand 24' in its proper position, is being returned toward the drilling mast 16 so that it will be in posi-' tion to engage the upper end of the next pipe stand 24 as it is unthreaded from the remainder of the drill pipe.

The foregoing procedure is repeated until the entire drill string is removed. To replace the drill pipe in the well bore, the foregoing procedure is reversed.

It should be pointed out that during the replacement of the drill pipe in the'well bore, transfer of the drill pipe stands 24 from the racking mast 12 to the drilling mast 16 can be quickly, and efficiently carried out since the lower end of the stands 24 will engage the pipe engaging means 52 thereby retaining the stand 24 in proper position for threading into that portion of the drill pipe that is alreadypositioned in the well bore. Thus,

the drill pipe stands 24 can be quickly and easily handled while making trips regardless of the angular position of the drilling mast 16 and without the unthreading of each joint and! without laying the pipe down.

THE EMBODIMENT OF FIG. 7

The drilling apparatus of FIG. 7 has been designated" generally by the reference character 100. It will be noted thatin the schematic view of FIG. 7 the structure is essentially the same as previously described in connection with the preferred embodiment of the invention. Accordingly, all parts whichare identical to those previously described have been designated" by the same reference charactersin FIG. 7.

Generally, it will be appreciated that the major change made has been in providing a straight track 118 in lieu of the curved track 18 illustrated in FIGS. 1 and 2. Also, the eccentric leg 174 shown in H6. 7 has been extended considerably as compared to the leg 74.

In operation, the trolley assembly 60 traverses the track 1 18 between the racking mast 12 and the drilling mast 16 as previously described. However, and since the track 118 is straight,

the leg 174 carrying the transfer elevator 76 has been lengthened to permit the upper end of the stand 24 to follow an arcuate path during traverse, as illustrated by the dash line in FIG. 7, so that the lower end of the stand 24 remains in engagement with the pipe engaging member 52 and in alignment with the center line of the well bore. The arcuate path of the upper end of the drill stand 24-is possible since the transfer elevator 76 can move downwardly in the leg 174 as the trolley assembly 60 traverses from the racking mast 12 to the drilling mast l6.

While the system is slightly more complex due to the necessity for coordinating the movement of the upper end of the pipe stand 24 as the trolley assembly 60 traverses the track 118, it does offer the advantage of having the straight track 118 rather than the curved track 18 of FIG. 1. The straight track 118 can be constructed more economically than the curved track 18.

THE EMBODIMENT OF FIG. 8

FIG. 8 illustrates still another embodiment of the invention wherein the drilling apparatus has been designated generally by the reference character 200. Again, the apparatus 200 is basically similar to the drilling apparatus 10 described in connection with FIG. 1. Accordingly, parts which are identical to those previously described are designated by the same reference characters.

in the apparatus 200, the straight track 118 has been employed on which the trolley assembly 60 traverses between the pipe racking mast l2 and the drilling mast 16. It will be noted that the leg 74 is constructed as described in connection with FIG. 1 and, therefore, the upper end of the pipe stands 24 will follow a substantially straight line path between the racking mast l2 and the drilling mast l6.

Since the pipe stands 24 are of fixed length, the lower ends thereof will of necessity move relatively upwardly as the trolley assembly 60 moves toward the drilling mast 16. To accommodate this upward movement, an elongated pipe engaging member 252 is provided in the lower end of the drilling mast 16. The pipe engaging member 252 is constructed to maintain the lower end of the pipe stands 24 on the centerline of the well bore during movement of the pipe stands 24 between the pipe racking mast l2 and the drilling mast 16 even though relative upward movement of the stands 24 does occur.

it will of course be necessary for the stands 24 to be raised slightly higher when moving them from the well bore and to be lowered somewhat more during replacement of the stands 24 in the well bore. Thus, there will be some inconvenience in manipulating the pipe stands 24, but again the advantage of utilizing the straight track 118 in lieu of the curved track 18 is realized.

It can be appreciated that the drilling apparatus described hereinbefore, provides the advantage of a safe, quick and efficient means of moving stands of pipe between a tilted drilling mast and a substantially vertical pipe racking mast while maintaining the lower ends of the pipe in alignment with the well bore whereby the pipe can be quickly and easily broken into stands or rejoined to form the drill string as the drill pipe is replaced in the well bore.

It will also be appreciated that the foregoing detailed description is presented by way of example only and that many changes and modifications can be made thereto without departing from the spirit and scope of the invention.

We claim:

1. Well drilling apparatus utilizing drill pipe to position a drill bit on the bottom of a well bore, said apparatus comprismg:

a substantially vertical pipe racking mast for storing multiple sections of the drill pipe in a substantially vertical 5 position;

a tiltable drilling mast spaced from said pipe racking mast, said drilling mast including a crown block mounted on the upper end thereof, a traveling block moveable in said drilling mast, and guide means for limiting the movement of said traveling block to coincide with the axis ofthe well bore; and

drill pipe transfer means for moving drill pipe between said pipe racking mast and said drilling mast, said transfer means including pipe engaging means mounted on said drilling mast for positioning the lower end of the drill pipe on the well bore axis during movement of the drill pipe from the racking mast to the drilling mast.

2. The well drilling apparatus of claim 1 wherein said pipe engaging means for positioning the lower end of the drill pipe 20 on the well bore axis during movement of the drill pipe from the racking mast to the drilling mast is elongated to permit movement of the lower drill pipe end along the well bore axis.

3. The well drilling apparatus of claim 1 wherein said drill pipe transfer means includes:

track means extending from said pipe racking mast to said drilling mast; and

trolley means moveable along said track means, said trolley means including pipe supporting means for supporting the upper end of the drill pipe and retain the drill pipe during movement of the drill pipe between said drilling mast and racking mast.

4. The well drilling apparatus of claim 3 wherein:

said track means includes a pair of parallel track members;

and

said trolley means includes a powered traveling bridge extending between and adapted for movement along said track members, a carriage track extending across said traveling bridge, and a powered carriage moveable along the carriage track to provide for the movement of the pipe in a direction generally perpendicular to the track members.

5. The well drilling apparatus of claim 4 wherein said trolley means also includes pipe supporting means mounted on said carriage for engaging and supporting the pipe during movement of the pipe between said racking mast and drilling mast.

6. The well drilling apparatus of claim 5 wherein said pipe supporting means includes means for elevating the drill pipe.

7. The well drilling apparatus of claim 1 wherein said transfer means includes:

track means extending from said racking mast to said drilling mast, said track means having an arcuate portion having a curvature generated by the locus of a point moving at a fixed distance from the tilting axis of said drilling mast; and

trolley means moveable along said track means, said trolley means including pipe supporting means for supporting the drill pipe during movement of the drill pipe between said drilling mast and racking mast.

8. The well drilling apparatus of claim 7 wherein said pipe 60 supporting means includes means for elevating the drill pipe.

9. The well drilling apparatus of claim 8 wherein: said track means includes a pair of parallel track members each having said arcuate portion; and said trolley means includes a powered traveling bridge extending between and moveable along said track members, a carriage track extending along the powered traveling bridge, and a powered carriage moveable along the carriage track to permit movement of the pipe in a direction generally perpendicular to the track members, said pipe supporting means being mounted on said powered carriage.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3443647 *Jul 1, 1968May 13, 1969Moore Corp Lee CSlant hole well drilling apparatus
US3451493 *Mar 29, 1967Jun 24, 1969Storm James CDrilling apparatus and method
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3805902 *Mar 26, 1973Apr 23, 1974Storm JWell drilling apparatus and method
US3937334 *Feb 3, 1975Feb 10, 1976Brown & Root, Inc.Pipe handling device
US3991887 *Feb 24, 1975Nov 16, 1976Trout Norman LMethod and apparatus for moving drill pipe and casing
US4586572 *May 10, 1984May 6, 1986Thomas A. MyersWell drilling apparatus
US6085852 *Mar 29, 1996Jul 11, 2000The Charles Machine Works, Inc.Pipe handling device
US6179065Sep 2, 1998Jan 30, 2001The Charles Machine Works, Inc.System and method for automatically controlling a pipe handling system for a horizontal boring machine
US6543551Feb 22, 2000Apr 8, 2003The Charles Machine Works, Inc.Pipe handling device
US6550547Feb 11, 2002Apr 22, 2003The Charles Machine Works, Inc.System and method for automatically controlling a pipe handling system for a horizontal boring machine
US8353369Aug 5, 2009Jan 15, 2013Atlas Copco Secoroc, LLCPercussion assisted rotary earth bit and method of operating the same
US8371074 *May 14, 2010Feb 12, 2013Redriven Power Inc.Mast assembly for wind turbine
US8782968 *Sep 21, 2009Jul 22, 2014Atlas Copco Drilling Solutions LlcPivotable tower for angled drilling
US20100313495 *May 14, 2010Dec 16, 2010Christopher Bernard GrantMast Assembly for Wind Turbine
US20110162296 *Sep 21, 2009Jul 7, 2011Atlas Copco Drilling Solutions LlcPivotable tower for angled drilling
EP0811108A2 *Feb 21, 1996Dec 10, 1997The Charles Machine Works IncApparatus and method for handling drill pipes
WO1996026349A2 *Feb 21, 1996Aug 29, 1996Charles Machine WorksApparatus and method for handling drill pipes
WO2010033935A2 *Sep 21, 2009Mar 25, 2010Atlas Copco Drilling Solutions LlcPivotable tower for angled drilling
Classifications
U.S. Classification414/22.53, 175/85, 173/196
International ClassificationE21B15/00, E21B19/14, E21B19/00, E21B15/04
Cooperative ClassificationE21B19/14, E21B15/04
European ClassificationE21B19/14, E21B15/04
Legal Events
DateCodeEventDescription
May 4, 1987ASAssignment
Owner name: IRI INTERNATIONAL CORPORATION, PAMPA, TEXAS, A COR
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:DRESSER INDUSTRIES, INC.;REEL/FRAME:004711/0917
Effective date: 19850731