CA1179321A - Lifting apparatus for handling down-hole tubulars - Google Patents

Abstract

IMPROVED LIFTING APPARATUS
FOR HANDLING DOWN-HOLE TUBULARS
ABSTRACT
An improved boom for a drill rig is described which includes two rotatably mounted clamps which are rotatable between a side loading position, to facilitate loading and unloading in the horizontal position, and a central position, in which a clamped tubular is aligned with the drilling axis when the boom is in the vertical position. An automatic hydraulic sequencing circuit is provided to automatically rotate the clamps in-to the side loading position whenever the boom is pivoted with a down-hole tubular positioned in the clamp. In this position, the clamped tubular is aligned with a safety plate mounted on the boom to prevent a clamped tubular from slipping from the clamps. A safety frame is formed between the tower of the drill rig and the vertical boom by a slidable bolt mounted on the tower and an annular receiving member mounted on the boom to receive the end of the bolt. This boom also includes an improved pivoting linkage which facilitates the transport of the rig.

Description

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IMPROVED LIFTING APPARATUS
FOR HANDL~NG DûW~--~1(3LE TUBU~ARS

This application ls a divis:ion of Canadian 5~rial No. 382,078, filed July 20j 1981.
The present in~ention relates to an impro~d apparatus for handling oil well and w~er well tubulars and rods, including but not limited ~o drill pipe, drill collars, well casing, production tubing, suclcer rods, pump column pipe, and the like, all of which tubulars, pipes, and rods are referred to herein simply as "down-hole tubulars." More particularly, this invention relates to such a handling apparatus which exhibits improved safety of operation and ease of use and setup.
In the past, drill rigs with top head rotary drives haye on occasion been provided with pivotably mounted pipe booms for raising and lowering lengths of down hole tubulars between the horizontal position, in which they are transported and stored, and the vertical position, in which they are aligned with the drilling axis of the rig to be joined to other lengths. Such booms facili~ate handling, assembly and disassembly of down-hole tubular strings.
The present invention is directed to an improved apparatus for handling down-hole tubulars in a drill rig, which is safe to operate and which can be easily operated, set-up for use, and partially disassem~
bled when necessary to move the drill rig.

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An object of this invention is to provide a drill rig mounted boom having rotatable clamps which can be positioned to at least one side of the boom to facilitate the loading and unloading of down hole tubulars into and from the clamps.
Another object of this invention is to provide a boom with such rotatable clamps wherein the clamp can be,rotated to bring a clamped down-hole tubular into alignment with the drilling axis of the drill rig.
Another object of this invention is to provide a boom with rotatable clamps, wherein the boom further includes means for raising and lowering the boom with a clamped tubular rotated out of the plane of the drilling axis, and means for automatically rotating the clamps to bring the clamped tubular into alignment with the drilling axis after the tubular has been raised substan-tially into a vertical position.
Another object of this invention is to provide an apparatus for handling down-hole tubulars which includes a boom and means for capturing a clamped tubular between the boom and the tower of the drill rig when the boom is in the vertical position, adjacent the drill rig tower.
Another object of khis invention is to provide an improved linkage between a drill rig and a boom, which linkage is easily stored for transport without, removing the lower portion of the boom or the li~kage , rom the drill rig and which is there,~ore readily taken down and set up when the drill rig is transported.
These and other objects o~ the in~ention are accomplished by providing an improved drill rig boom having clamps for handling down-hole ~ubulars. According to a first ~eature of the invention, a pipe boom includes rotatably mounted clamps for holding down-hole tubulars.
These clamps are rotated into a first position to facilitate side loading and unloading of down-hole tubulars between the clamps and a substantially horizontal _3_ ~ 3~

support structure such as a pipe rack or a truck bed.
Once the down-hole tubular is loaded, the clamps can be rotated to a second position in which the clamped down-hole tubular is alligned with the drilling axis of the drill rig, i.e. the centerline of the drill string.
Preferably, means are provided for automatically rotating the clamps into the second position whenever the boom is moved without a tubular clamped in the clamps, and for automatically rotating the clamps into the first position whenever the boom is moved while a tubular is clamped in place.
According to a second feature of the invention, means are provided for guiding the boom into an alligned position with respect to the drill rig tower when the boom is raised to the vertical position. This guiding means can be configured in a nurnber of ways to perform one or more of the following ~unctions. First, th~
guiding means can be configured to capture a vertically oriented tubular between the boom and the tower of the drill rig when the boom is in the vertical position, thereby preventing clamped tubulars from falling out of ~he tower in the event of clamp failure. Second, the - guide means can include a sleeve mounted on the tower, a bolt slidably mounted in the sleeve, and an annular receiving member mounted on the boom to receive the bolt when the boom is in the vertical position adjacent the tower. In this way, the guiding means can be made to retract quickly and easily in order to reduce the roading height of the rig when the tower is lowered to the horizontal position. Third, the guiding means can be configured to trans~er torques exerted on a clamped tubular from the clamps, via the boom, to the tower, thereby preventing twisting o~ the boom. This feature of the guiding means is particularly important when the boom is used in connection with a top head drive, power swivel, or the like, to make up and break out strings o down-hole tubulars.

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According to a third feature of the invention, the boom includes a safety plate mounted on the boom to restrain downw~rd, longitudinal movement of a clamped tubular if it should slip in the clamps. Preferably, this safety plate is used with the rotatably mounted clamp descxibed above and the safety plate is positioned such that the plate does not restrict longitudinal movement of a clamped tubular which i aligned with the drilling axis of the rig.
According to a fourth feature of the invention, the boom is formed in two sections which can be readily assembled and disassembled. The lower boom section is pivotably mounted to the drill rig and is positioned by a linkage which includes a tension member and two compression members, one of which includes a hydraulic cylinder. This linkage is arranged such that, when fully assembled, the hydraulic cylinder operates to raise and lower the boom. As the boom is in the raised position, khe linkage is preferably mo~ed to a raised position as well. Because the upper portion of the boom is removable, ~he rig can be kept to an acceptable height and a lower weight for transport. In addition, because the lower portion of the boom can be kept permanently mounted to the drill rig, set-up time and take down time are reduced. Preferably the upper boom is held to the lower boom by two pins to further speed assembly and disassembly of the boom.
The principal advantages of this invention are improved speed and safety of operation. The captur-ing means and the sa~ety plate cooperate to confineclamped down-hole tubulars and to preven~ a tubular which has slipped ~rom the clamps from escaping and falling. The automatically rotated clamp provides the further advantage that a clamped tubular is maintained in alignment with the safety plate until the boom reaches the vertical position and the clamped tubular is restrained by the capturing means. The boom of this 79~Zi invention also provides increased sa.~ety ~ecause a length o~
tubular can be rai`sed or lowered with a mInim~m of manual con-tact with the tubular. This keeps operatin~ personnel away from the moving tu~ulars, and reduces the number of personnel needed to operate the rig.
The rotatable .clamp of this invention provides the furth.er ad~antage that the clamp can be rotated fc,r easy loading and unloading. The boom o~ this invention is well suited for automated or sem;-automated pipe handling systems, especially those in whi:ch gravî~ty loading and unloading is used.
The improved linkage of this boom provicles the advan-tage of quick set-up and stowing of the boom. The pivot con-nection ~et~een the boom and the drill rig need not be disas-~emb.led in order to stow the ~oom for transport, and reassembly is therefore relatively quick.
l'hus broad].y:, the in~vention contemplates a drill rig which includes a tower for supporting a string of down-hole tubulars, and a boom pivotably mounted to the rig adjacent the tower to move bet~een a h.orizontal position and a vertical position, substantially parallel to the tower. The boom includes upper and lo~er clamps for clamping and holding a down-hole tubular, and the improvement comprises, a safety plate mounted to th.e ~oom aliyned to prevent a clamped down~hole tuhular from sl~pping longitudinally in the clamps beyond tha safety plate as the boom moves betw~en the horizontal and vertical positions, with that safety plate positioned to prevent the clamped down-hole tu~ular from slipping out of the upper clamp.
The invention also contemplates a drill rig which includes a tower for supporting a string of down-hole tubulars and a boom pivotably mounted to the rig adjacent the tower to move bet~een a parallel to the tower, with the boom includiny a clamp for clamping and holding a down-hole tubular. The improve-ment comprises a support member mounted to the tower, a bolt slidably mounted to the support member and movable between a ~irst position, in which the bolt is retractecl toward the support member, and a second position, in which the bolt is extended away from the support member on th.e side of the tower faciny the boom, 5~ 7~
and means for locking the bolt in the second position~ A ~lock-îng memher î~ mounted to t~e ~OQm and ;~ alLgned with the ~olt such that the ~olt su~stantîally a~uts the ~locking mem~er when the ~oom is în the vertlcal posît;on substantially parallel to the to~r, and the support mem~err ~olt, and blocking mem~er are positionea to pro~ide a safety.fr~me ~etween ~he boom and the tower at a level adapted to restraîn the movement of vertically po~îtîoned do~n-hole tubulars ~et~een the tower, the boom, and the frame.
rn another embodiment, the invention contemplates a drill rig ~hich includes a tower for supportiny a string of do~n-hole tu~ulars, and a ~oom pivota~ly mounted to the rig adjacent the tower to move between a ~orizontal position and a vertical position, s~tantially parallel to the tower, the ~oom includ-ing upper and lo~er clamps for clamping and holding a down-hole tuhular. The i~pro~ement comprises means for rotatably ~ounting the clamp~ on the ~oom 50 as to rotate about an axis substantial-ly parallel to the boom, a sa~ety plate mounted to the boom aligned to prevent a clc~mped down hole tu~ular from slipping longitudinally in the clamps beyond the safety plate as the boom move~ ~et~een the horizontal and ~ertical po~itions when the clamp i5 in a first position, ~ith the safety plate positioned to preYent the clamped tu~Nlar from slipping out of the upper clamp, and means for rotating the clamps between the first po~iti.on, in ~hich the clamped tu~ular is aligned with the safety plate, and a second position, in which the clamped tubular is moved out o~ alî~nment ~ith the safety plate and into alignment ~îth. th.e drï.llîng axi.s o khe rig ~hen the boom is in the verticcal po~ition. A means automati¢ally controls. the rotating means ~uch that the clamps are automatically rot.ated into the irst position ~hene~er a down-hole tu~ular is beiIIg held in the clamp and the hoom is being pivoted between the horizontal and vertî.cal position, and a means captures a clamped tubular bet~een the tower and the boom when the boom is in the vertical position such. that a vertical t~ular is prevented from falling a~a~ from the tower.

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The invention, in it~ broadest aspect, contemplates a drill rig which includes a tower for supporting a string of down-hole tubulars and a boom pivotably mounted to the rig adjacent the tower to move between a horizontal position and a vertical position, substantially parallel to the tower. The boom includes a clamp for clamping and holding a down-hole tubuIar.
The improvement comprises means for rotatably mounting the clamp on the boom so as to rotate about an axis substantially parallel to the boom. A means is provided for rotating the clamp between a first position in which the clamp is oriented with its loading axis aligned in a substantially horizontal direction when the boom is in the horizontal position to facilitate loading and unloading the clamp, and a second position in which the clamp is orien~ed to align a clamped tubular with ~he drilling axis of the rig when the boom is in the vertical position.
The improvement outlined abo~e ~urther includes a means for guiding a horizontally oriented down-hole tubular to roll from a storage position in a direction aligned with the substantially horizontal loading axis of the clamp in the first position in order to roll the tubular into the clamp.
In a further embodiment, the invention provides a mounting apparatus for mounting a boom for lifting down-hole tubulars to a mobile drill rig. The apparatus comprises a means for pivotably mounting the boom to the drill rig, a hydraulic cylinder, a means for mounting the cylinder between the boom and the drill rig such that the weight of the boom is entirely transmitted directly to the rig, and a tension member, included in the mounting means, mounted between the boom and the cylinder to pro~ide a reaction point to the cylinder.

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-5c-The ;nventïon, toget~er ~t~ further o~jects and attendant advantages will ~e ~est understood ~y reference to the fol~owing detailed description taken in connection ~ith t~e accompanying drawings.
FIGURE 1 is an elevational view of a mobile drill.rig încluding a preferred em~odiment of the ~oom of this in~ention pivoted to the vertical positionO
FIGURE 2 is a cross~sectional view taken along line 2-2 of Figure 1 showing a clam~ rotated to align the clamped down-hole tu~ular with the drilling axis of th.e drill rig.
FIGUR~ 3 is a plan vîew o a portion of the rig of Fig~re 1 showing the ~oom in the hori~ontal position.
FIGURE 4 is a cross-sectional view taken along line 4-4 o~ Figure 3~
FIGURE 5 is an end view taken along line 5-5 of Figure 3 showing a clamp rotated to load a down-hole tu~ular.

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FIGURE 5a is a partial perspective view of one of the two ramps of the boom of Figure 1.
FIGURE 6 is an elevational view of a portion of the rig of Figure 1 showing ~he boom partially disassembled and stowed for drill rig transport.
FIGURE 7 is a cross-sectional view of a portion of the boom taken along line 7-7 of Figure 1, appearing with Figures 1 and 2.
FIGURE 8 is a diagrammatic representation of the operation of the boom of Figure 1.
FIGURE 9 is a schematic representation of the hydraulic circuit of the boom of Figure 1.
Referring now to the drawings, Figure 1 shows a mobile, transport mounted drill rig 10 including a tower 12 and a boom 14 pivotably mounted to the rig 10.
The boom is pivotable between a vertical position adjacent the tower 12 (shown in solid lines), and a horizontal position (partially shown in dotted lines).
Two clamps 16 for clamping and holding dow~-hole tubulars such as a length of drill pipe 40 are rotatably mounted on the boom 14 in co-linear alisnment.
Each clamp 16 is mounted on an axis 18 which is pivotably supported between two spaced, parallel plates 20,22. A
hydraulic cylinder 24 is trunnion mounted between the plates 20,22, and the clamp 16 such that contraction and elongation of the cylinder 24 rotates the clamp 16 with respect to the boom. Each clamp 16 includes a pair of opposed clamping members 42 which are positioned by hydraulic cylinders (not shown) to clamp and hold the drill pipe 40.
A hollow sleeve 28 is welded to each side of the tower 12, perpendicular to the boom 14 when in the vertical position shown. Each of these sleeves 28 is pre~erably formed rom 4-1/2 inch drill pipe, and each contains a longitudinal slot 30 which is provided with a downwardly projecting angle as shown. Positioned in each sleeve 28 is a pointed bolt 32. Each bolt is slideable in the respective sleeve 28 between an extended _7_ ~7~

position (as shown) in which the pointed end of the bolt 32 extends outwardly toward the boom 14, and a retracted position (not shown) in which the bolt 32 retracts into the sleeve 28 to a point where the pointed end of the bolt 32 is substantially flush with the edge o the tower 12 adjacent the boom 14. Each bolt 32 includes a pin 36, mounted to the bolt 32, which projects through the slot 30 and locks the bolt 32 in the e2tended position when positioned in the downwardly projecting angle of the slot 30 as shown.
The boom 14 is provided with a pair of annular receiving membexs 34 mounted to the boom 14 via a gussetted I-beam 38. The recei~ing members are funnel shaped and are positioned to align with and receive the extended bolts 32 when the boom is in the vertical position shown. The receiving members 34 are pre-ferably equipped with elastomeric pads 34a or o~her shock absorbing means to help insulate tower 12 from shoc~s resulting from suddenly stopping boom 14 and tubular 40 as same are rotated into tower 12 about pins 64. Figure 4 shows a cross-section of the boom 14 including the receiving members 34. As best seen in Figure 2, the sleeves 28, bolts 32, and receiving members 34 cooperate to achieve four objectives:
first, to confine a clamped drill pipe 40 when the boom 14 is in the vertical position, thereby preventing the drill pipe 40 from tipping away from the tower if it should fall from the clamps }6; second, to stop, align and stabilize boom 14 with respect to the tower lZ so as to assure. accurate alignment and make up of drill pipe 40 with a swivel saver sub (not shown); third, to help stabilize boom 14 when high torque is applied by a power swivel or top head drive (no~ shown) to make up or break ou~ drill pipe 40 to or from the swivel saver sub; and fourth, ~o cusion the shock of stopping boom 14 and tubular 40 as same are rotated into tower 12 about pins 64.

-8~ ~7~3~1 The boom 14 is also provided with a safety plate 46 which is securely welded to the boom 14 and braced by gussets. A resilient pad 48 of rubber or other shock absorbent materials is secured to the upper face of the safety plate 46. This safety plate is positioned to obstruct longitudinal movement of the pipe 40 down through the clamps 16 when the clamps are ro~ated in the position shown in Figure 5. This pre-vents a clamped pipe from slipping, whether due to operator error or equipment failure, out of the clamps 16 while it is being raised or lowe.red. This resilient plate does not interfere with the downward movement of the clamped pipe 40 once the clamps 16 have been ro-tated to bring the pipe 40 into alignment with the drilling axis of the drill rig, as shown in Figure 2.
At this point the safety plate is no longer needed, for the bolts 32 and the tower 12 cooperate to restrai~ a vertical tubular. Furthermore, the safety plate 46 would interfere with the makeup of a string if it projected too near to the drilling axis.
Figures 3 and 5 show a length of drill pipe 40 being loaded into the clamps 16 of the boom 14. The pipe 40 is supported on a pair of conventional pipe racks 44, and the clamps 16 are rotated to the side for easy loading. In the illustrated clamp, the pipe 40 enters the clamp 16 by moving along a loading axis, which is horizontal when the clamp 16 is rotated as shown in Figure 5. This facilitates gravity loading and unloading, as the ends of the pipe racks 44 ne~t to pipe clamps 16 need to be raised or lowered only an inch or so to cause down hole tubulars to roll into or out o~ clamps 16. Such slight tilting o~ pipe racks toward or away from boom 16 is easily accomplished by means known to those Eamiliar with the art of rotary drilling.
P.ipe boom 16 is e~uipped with an adjustable boom stop 61 whereby the height of clamps 16 can be _9_ ~7g3~

adjusted to the height o~ pipe racks 44. When properly adjusted by the boom stop 61, pipe racks 44 and pipe clamps 16 are in the respective ele.vations shown in Figure 5. Thus, pipe 40 can be rolled into or away from clamps 16 by gravity simply by changing very slightly the elevations of ends of pipe racks 44 that are arthest away from pipe clamps 16. The boom in-cludes two ramps 35 which can be adjusted to either a loading position, in which a ramp is created which slopes down to the clamp, or an unloading position, in which a ramp is created which slopes down to the rack.
A perspective view of one of the ramps 35 mounted to the boom 14 is shown in Figure 5a. Alternatively, adjustable slope ramps 35 may be mounted on clamps 16.
The boom 14 includes means for automatically sequencing the rotation of the clamps 16 for maximum safety and ease of loading and unloading pipe clamps 16. Figura 8 schematically shows the sequence of events. Briefly, if the boom is loaded with a length 20 of clamped tubular, the clamps 16 are automatically placed in the ofset position shown in Figure 5 when-e~er the boom moves into or away from the vertical position. The clamps are moved from the offset position to the central position (shown in Figure 2) after the boom reaches the vertical position when a tubulax is being raised and before the boom leaves the vertical position when a tubular is being lowered. In this way the clamped tubular is always aligned with the saety plate when i~ is being either raised or lowered and, also, is caused to be property oriented with respect to pipe racks when horizontal.
When the boom 14 is pivoted without a tubular in the clamps 16, the sequence is reversed. That is, the clamps are moved from the offset to the central position before the boom is raised, and ~rom the cen-tral position to the of~set position after the boom is lowered. This properly places the clamps 16 in the '"''' '' ' ' " .

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central position when the boom 14 is raised to clamp and lower a tubular suspended on ~le drilling axis.
Fi~ure 9 presents a schematic representation of the hydraulic circuit of this preferred embodiment that automatically se~uences the rotation of the clamp 16 as described above. Figure 9 schematically sho~s the boom cylinder 26, the clamp rotation cylinder 24 and the clamp 16. Also included in the circuit is a manually controlled valve 80 for controlling the cylinder 26 to raise and lower the boom 14. Manually controlled valve 82 controls the clamp 16 ~o close and open the clamp. These two valves are coupled in series between a source of pressurized hydraulic fluid (desig-nated "Pressure") and a low pressure tank ~designated "Re~urn"). For example, when the valves 80,82 are in the positions shown, both the cylinder 26 and the clamp 16 are static. Moving valve 80 to the right causes the cylinder 26 to extend and the boom 14 to lift, while moving valve 80 to the ~eft causes the cylinder 26 to retract and the boom 14 to lower. Similarly, moving valve 82 to the right closes the clamp 16 and moving the valve 82 to the left opens the clamp 16.
Also included are accumulators 84,85, a valve 86 responsive to boom position, and a valve 88 respon-sive to the state of the clamp 16 (open or closed).Valves 90,92 are pilot-operated check valves which block flow into the cylinder 24 except when pressure is applied on lines 94,96, respectively. Valve 98 blocks 10w out o~ the accumulator except when pressure is applied on line 100.
In operation, the valve 86 is moved to the lower position when the boom 14 is in the vertical position, to the upper position when the boom 14 is in the horizontal position, and it remains in ~he position shown when the boom is in the in~ermediate position.
This ensures that the clamp 16 does not rotate when the boom 14 is in an intermediate position.

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When valve 82 is moved to the xight, the clamp 16 is closed and pressure is applied via line 102 to open the valve 98 and to move the valve 88 into the lower position. This ensures that the accumulator 84 supplies pressure to hold the clamp 16 closed in the event of a drop in the pressure of the supply. Further-more, with the valve 88 in the lower position, when valve 80 is moved to the right, the clamp 16 is rotated into the offset position for side loading when the boom is down, is held in this position as the boom is raised, and automatically rotates to the central position when the boom reaches the vertical position. When tubulars are ~eing lowered and the clamp is closed while the boom is in the vertical position, once valve 80 is moved to the left the clamp 16 is rotated from the central position to the offset position while the boom is in the vertical position, and then the boom is lowered with the clamp in the offset position.
The situation is reversed when the clamp 16 is opened and pxessure on line 104 raises the valve 88 into the upper position. In this case, the clamp is held in the central position as the boom is pivoted, and ~he clamp can only be rotated to the offset po-sition after the boom has reached the horizontal position.
In the foregoing discussion the terms left, right, upper, and lower are used in connection with the valves 80,82 86,88 only to designate directions as shown on the drawing of Figure 9, and these terms are not to be construed as having any physical significance.
Figures 3, 6 and 7 show another eature of the invention which ~acilitates set-up and stowing of the boom 14. The boom 14 is made up of an upper boom section 52 and a lower boom section 50. The lower boom section 50 is pivotably connected to the drill rig 10 at two points via a pin an~ a clevis. A plate 54 forms one end o~ the lower boom section 50. The upper boom ,. . . .

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section 52 also includes a lower plate 22 which can be mounted to the plate 54 by fasteners such as a combina-tion of lugs and pins.
As shown in Fi~ure 7, the lower boom section 50 preferably includes a pair of lower spaced lugs 70 which are positioned to mate with spaced clevis lugs 59 mounted on the upper boom section 52. A pin 53 is placed through matching openin~s in the lugs 70 and the clevis lugs 59 to secure the upper boom section 52 firmly to the lower boom section 50. As shown in Figure 1, a total of two pins 53, 55 are used to secure the upper boom section 52 to the lower boom section.
Preferably, the pin 55 locks spaced clevis lugs mounted on ~he lower boom section and mating lugs mounted on the upper boom section. Prefexably~ the upper pin 53 and lower pin 55 are solid steel rods approximately

3 inches in diamter.
Of course, an alternate approach is simply to bolt the upper and lower boom sections together.
~owever, the use of pins and lugs is faster and more reliable, and it eliminates the problem of differential tor~ues among several bolts. Furthermore, the pin and lug arrangement of this preferred emobodiment is easier to assemble in the ~ield, since only one set of lugs needs to be aligned at a time. Preferably, the pins 53,55 are slightly tapered in order ~o facilitate allignment and are provided with enlarged heads so they can he hammered into place.
A tension member 58 is pivotably mounted to each pin 64, and i5 pivotably connected to two compxes-sion members 26,56, one o~ which 26 includes a hydrau-lic cylinder in this embodiment. In other embodiments the hydraulic cylinder can be placed between the rig 10 and the tension member 58. ~n operation, the cylinder ~6, the tension member 58, and the compression member 56 cooperate such that elongation and shortening of the cylinder 26 causes the boom to pivot. As the boom rises from the horizontal to the vertical position as shown in Figure 1, the compression m~mber 56 pivots to a near horizontal position. Here it should be noted that the boom is supported from the rig entirely by the linkage members 56,58, 28 and the pivot 64. No addi-tional contact is made with the ground to support the weight of the boom as it is pivoted between the hori zontal and the vertical positions. This is an addi-tional feature of the in~ention which further reduces set-up and take-down time.
Referring now to Figure 6, the boom 14 can be stowed as follows. First, the upper boom section 52 is removed from the lower boom æection 50 while in the horizontal position by removing the pins 53,55. The upper boom section 52 is ~hen transported separately from the rig 10, as in a pipe truck for example. Then the lower boom section 50 is raised with the cylinder 26 to the vertical position and then chained in posi-tion with a chain 60 to complete the stowing of the boom. As the lower boom section 50 was raised, the compression member 56 automatically pivoted into an upper position which is removed ~rom ground level - adeguately to permit highway transportation of the rig.
Thus, the lower boom section 50 need not be dismounted from the rig in order to prepare the rig for highway travel. Since lower boom section 50 is a~ways powered it can be used as a rudimentaxy crane for lifting and positioning such heavy items as blowout preventors, slips, large drill bits/ and the like. The boom can be guickly and easily returned ~o service merely by re moving the chain, lowering the lower boom section 50 to the horizontal position, and then securing the upper boom section 52 to ~he lower boom section 50 with the pins 53,55. Thus, the boom 14 can he quickly returned to service and the rig 10 is always complete with at least a rudimentary materials handling boom.

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As shown in Figure 6, the tower 12 is made in two pivoted parts, the upper of which is lowered to a horizontal position when the rig is to be transported.
The lower section of the boom 50 does not extend above the height of the lowered tower 12 and thus does not present an additional obstruction to bridges and the like under which the rig must pass. Similarly, the bolts 32 retract to a position which does not extend substantially above the top of the tower 12 when it is lowered to the horizontal position.
From the foregoing it should be apparent ~hat an improved pipe handling apparatus has been described which requires little or no manual contact with a down-hole tubular either to raise the tubular to build up a string of tubulars, or to disassemble a string of tubulars and lower a tubular. This apparatus includes important safety feakures to restrain a tubular if it should slip, either when moving in the boom or when being rotated, when in the vertical position, into a centerline of the drill string. Furthermore, the apparatus is readily placed in a compact configuration suitable for rig transport.
Of course, it should be understood that various changes and modifications to the preferred embodiment described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present invention, and without diminishing its attendant advantages. It is, therefore, intended that such chanyes and modi~ications be covered by the ~ollow-ing claims.

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Claims (7)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A mounting apparatus for mounting a boom for lift-ing down-hole tubulars to a mobile drill rig, said apparatus comprising:
means for pivotably mounting the boom to the drill rig;
a hydraulic cylinder;
means for mounting the cylinder between the boom and.
the drill rig such that the weight of the boom is entirely transmitted directly to the rig;
a tension member, included in the mounting means, mounted between the boom and the cylinder to provide a reaction point to the cylinder.

2. The apparatus of Claim 1 wherein the mounting means further includes a compression member mounted between the tension member and the drill rig, said compression member mounted to pivot to a substantially horizontal position when the boom is raised to a vertical position.

3. An improved boom for lifting down-hole tubulars in a mobile drill rig, said boom comprising:
a first boom section;
a second boom section;
means for reversibly mounting the second boom section to the first boom section end-to-end to form a boom, said mounting means permitting the second boom section to be readily disassembled from and reassembled with the first boom section;
means for pivotably mounting the first boom section to the drill rig;
a tension member having a first end pivotably mounted to the first boom section;

Claim 3, cont'd.

first and second compression members, one of which includes a hydraulic cylinder, said first compression member mounted between the tension member and the drill rig, said second compression member mounted between the tension member and the first boom section, such that elongation of the hydraulic cylin-der pivots the first boom section from a first, substantially horizontal position, to a second, substantially vertical posi-tion and the first compression member is raised toward the drill rig when the first boom section is pivoted to the second position.

4. The boom of Claim 3 wherein the hydraulic cylinder is included in the second compression member.

5. The boom of Claim 3 wherein the first compression member is substantially horizontal when the first boom section is in the second position.

6. The boom of Claim 3 wherein the first boom section has a length such that when positioned in a substantially vertical position, the first boom section does not extend above the highest point on the drill rig when the drill rig is in a roading configuration.

7. The boom of Claim 3 wherein the means for reversibly mounting the second boom section to the first boom section includes a pair of pins which cooperate with mating lugs mounted on the first and second boom sections.