AU4929396A - Pipe handling device - Google Patents

Description

APPARATUS AND METHOD FOR HANDLING DRILL PIPES

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of pending U.S Patent Application Serial No. 08/392,072 filed on February 22, 1995.

TECHNICAL FIELD OF THE INVENTION

This invention relates to the handling of pipe for a horizontal boring device.

BACKGROUND OF THE INVENTION In recent years, many utility lines have been laid or replaced by use of a horizontal boring machine which eliminates the need to dig a trench from the surface to install or replace the utility. This technique has generally come to be known as trenchless technology. In a typical horizontal boring machine, a bore hole will be formed with a steerable bit. The boring machine will be mounted at the surface. One hydraulic motor on the boring machine causes the drill bit and drill string to rotate while another thrusts the drill bit and drill string forward as the bore is formed. It is also common to backream the bore with the machine, rotating a backreaming tool while drawing back the drill string to the boring machine.

The drill string is formed of a plurality of individual drill string sections threaded together. As the machine initially bores the hole, additional drill string sections must be added as the bore is lengthened. Similarly, when backreaming the bore, the individual drill string sections must be removed. Traditionally, this activity has been done by hand, with the assistance of wrenches on the drilling machine. There has also been a requirement to store the individual drill string sections before and after use. The typical horizontal boring device requires a three man crew. To increase efficiency and reduce cost, it would be of great benefit to provide an automated system for placing drill pipe sections in or removing drill pipe sections from the boring machine automatically during operation. Ideally, this would eliminate the need for a third man in the operation and permit the boring machine to be operated with a crew of two. In addition to an increase in efficiency and reduction of cost, eliminating the use of an individual to manhandle the drill pipe sections would reduce the chances for injury.

SUMMARY OF THE INVENTION

In accordance with one aspect of the present invention, an automatic pipe handling device for moving a pipe section from a storage position to a spindle center line position on a drill rig comprises a support frame mounted on the drill rig. A member is pivotally mounted to the support frame for pivotal motion about an axis generally parallel the spindle center line between a first position and a second position. At least one pipe gripper extends from the member to grip a pipe section, the gripper gripping the pipe section at a storage position when the member is in the first position and gripping the pipe section in the spindle center line position when the member is in the second position. A hydraulic motor is used to pivot the member between the first position and the second position.

In accordance with another aspect of the present invention, the automatic pipe handling device includes a drill pipe rack. The drill pipe rack is mounted on the support frame. The member is pivotally movable to a third position, the member returning a pipe section to the drill pipe rack at the third position and picking up a pipe section from the drill pipe rack at the second position. BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention and for further advantages thereof, reference is now made to the following description of the preferred embodiment, taken in conjunction with the accompanying drawings, in which:

FIGURE 1 is a perspective view of an automatic pipe handling device forming a first embodiment of the present invention; FIGURE 2 is a partial cross-sectional view of taken along view A in FIGURE 1;

FIGURE 3 is a perspective view of a modified pipe rack for use with the device;

FIGURE 4 is a side view in cross-section of the pipe rack of FIGURE 3 ;

FIGURE 4A is a detail view of the rack of FIGURE 4 illustrating the rubber straps cushioning the pipe section movement;

FIGURE 5 is a partial cross-sectional view of the pipe rack of FIGURE 3;

FIGURE 6 is a partial cross-sectional view of a modification of the pipe rack of FIGURE 3 ;

FIGURE 7 is a perspective view illustrating another modification of the automatic pipe handling device; FIGURE 8 is an end view of the device of FIGURE

7;

FIGURE 9 is an exploded view of a portion of the device of FIGURE 7;

FIGURE 10 is an exploded view of a pipe loader used in a pipe handling device forming a modification of the invention;

FIGURE 11 is a side view of the extension frame of the pipe loader;

FIGURE 12 is an end view of the extension frame; FIGURE 13 is a schematic view of hydraulic circuits in the device;

FIGURE 14 is a top view of the pipe box used in the device;

FIGURE 15 is a side view of the pipe box; FIGURE 16 is an end view of the pipe box;

FIGURE 17 is a perspective view of a cylinder mount and rotation member mounted thereon for limited pivotal motion; FIGURE 18 is a plan view of a pivot adjust stop;

FIGURE 19 is a top view of the rotation arm;

FIGURE 20 is an end view of the rotation arm; and

FIGURE 21 is a perspective view of the end panel on the pipe box.

DETAILED DESCRIPTION

With reference now to FIGURES 1 and 2 , an automatic pipe handling device 10 is illustrated which forms a first embodiment of the present invention. The device includes a support frame 12 which is permanently attached to the drill rig 14. The drill rig 14 is not illustrated in its entirety as it is a conventional and well known device. A pipe rack 16 is removably attached to the support frame 12 to store pipe sections 18 (see FIGURES 4, 5 and 6) when not in use by the drill rig. The support frame 12 mounts a longitudinal shaft

20 which is mounted for rotation about an axis 22 which is parallel the spindle axis 24 of the drill rig 14. The spindle axis 24 is the axis along which the drill string extends and is the axis of rotation of the drill string at the drill rig. To insert a pipe section 18 within the drill string, or remove the pipe section, the pipe section must be laid along the spindle axis 24 or removed from the spindle axis 24.

The longitudinal shaft 20 is rotatable by a hydraulic drive motor 26. Two hydraulic cylinders 28 and 30 are mounted along the length of the shaft 20 and are mounted perpendicular to the axis 22. At the end of the piston of each of the cylinders 28 and 30 is mounted a spring loaded pipe gripper 32. Grippers 32 include fixed fingers 33 and spring loaded fingers 35 urged to grip the pipe section by springs 37. The grippers 32 include guide shafts 34 which slide within brackets 36 mounted on the cylinders 28 and 30 so that the movement of the pipe grippers is only along an axis perpendicular to the axis 22.

The pipe rack 16 is formed of a frame weldment 38 including an upper bracket 40, a lower bracket 42 and side plates 44 and 46. Bars 60 and 62 extend between the side plates as well. Each side plate mounts a lifting eye 48 and is provided with aperture 50 to attach the pipe rack 16 to the support frame 12. An elongated aperture 57, located on bracket 56 of support frame 12, engages tab 59 located on the base of pipe rack 16 as the pipe rack is loaded onto support frame 12. Pins 52 are inserted through apertures 54 in brackets 56 on the support frame 12 and through the apertures 50 in the side plates 44 and 46. The pins 52 have a through hole to receive a locking clip 58 to secure the pipe rack on the support frame despite vibration or movement of the boring machine. However, the pipe rack 16 can be relatively easily removed from the support frame 12 by removing the pins and lifting the pipe rack off the frame. Near each end plate of the pipe rack is mounted a labyrinth track 64 which cooperates with a guide 66 mounted on the inside surfaces of the side plates to form an S- curve path 72 to guide drill pipe within the pipe rack from a return position 68 formed at the top of the pipe rack to a pick up position 70 formed at the bottom of the pipe rack. Attached to each end plate is a guide strip made from a low friction plastic such as UHMW (Ultra High Molecular Weight) plastic, to permit the use of shoulderless pipe in the pipe rack. Assuming that pipe sections are to be added to the drill string and are presently stored in the pipe rack 16, the pipe rack will first be attached to the support frame 12. The drive motor 26 will then be activated to cause the longitudinal shaft 20 to pivot so that the spring loaded pipe grippers 32 are facing the pipe section at the pick up position 70. The hydraulic cylinders 28 and 30 are activated to extend the pistons thereof so that the pipe grippers 32 move against and over the pipe at the pick up position. The hydraulic cylinders 28 and 30 are then retracted, drawing the pipe section from the pick up position and out of the pipe rack. The hydraulic drive motor 26 is then again activated to pivot the longitudinal shaft 20 until the pipe grippers 32 are directed toward the spindle axis 24. The hydraulic cylinders 28 and 30 are again activated to extend the pipe grippers to position the pipe section along the spindle axis 24. The mechanisms of the horizontal boring machine, not shown, then thread the pipe section into the drill string. After the pipe section is threaded, the cylinders 28 and 30 are retracted, pulling the pipe grippers 32 off the pipe section just inserted in the drill string.

If a plurality of pipe sections were stored in the pipe rack 16, when the pipe section in the pick up position 70 is removed by the pipe grippers, the remaining pipe sections 18 in the pipe rack, guided by the S-curve path 72 formed between the labyrinth track 64 and guides 66 at each end of the pipe rack, will move via gravity to urge the next pipe section in line into the pick up position 70. In this manner, each of the pipe sections in the pipe rack 16 can be individually removed from the pipe rack and positioned on the spindle axis 24 to be made up as part of the drill string. Block plates 74 on each of the side plates prevent the pipe section in the pick up position 70 from simply falling out of the pipe rack.

When the boring has been completed, and pipe sections are to be removed from the drill string, the device works essentially in reverse. The longitudinal shaft 20 will be pivoted by hydraulic drive motor 26 to grasp a pipe section 18 on the spindle axis 24. However, instead of being pivoted to the pick up position 70, the longitudinal shaft 20 is rotated by hydraulic drive motor 26 so that the pipe grippers 32 face the return position 68. The hydraulic cylinders 28 and 30 are then extended to move the pipe section 18 into the return position 68. The shaft 20 will then be rotated slightly to move the pipe section inside a portion of the tracks 64 so that when the hydraulic cylinders 28 and 30 are retracted, the pipe section will be held in place by the track plus the end guides 64 and the pipe grippers 32 will be removed from the pipe section. Alternatively, a reverse stop 65 (see FIGURE 4) can be mounted on the pipe rack which pivots out of the way to allow the pipe section to be inserted in the return position but then pivots back by gravity to block the pipe section from falling out of the pipe rack. Once removed, the pipe section will fall by gravity along the S-curve path 72 between the tracks 64 and guides 66 until it contacts the next previous pipe section inserted into the pipe rack. As pipe sections are removed from the drill string, these steps can be repeated until the pipe rack is completely full of pipe sections and ready to be used again to form another bore. If the drill string contains more pipe sections than pipe rack 16 can hold, the full rack is simply removed and replaced by an empty rack to continue the process.

If heavier pipe sections are used, the spring loaded pipe grippers 32 can be replaced by pipe grippers actuated by hydraulic cylinders. A detent device 73 on one end of the shaft 20 can assist in indexing the shaft in the positions described above.

The use of the S-curve path and the end guides permit straight, shouldered, bottlenecked, shoulderless or any other style of pipe sections to be used. A number of rubber straps 126 can be mounted within the pipe rack 16 to slow the fall of pipe sections within the rack as seen in FIGURE 4A.

The sequence of operations of the device illustrated in FIGURES 1 and 2 would be for the load sequence to move pipe sections from the rack to the drill string:

1. extend grippers toward pick up position of rack; 2. grip pipe section in pick up position;

3. retract grippers to remove gripped pipe section from pick up position; 4. rotate grippers with pipe section toward spindle axis and extend grippers;

5. retract grippers to release grippers from pipe section;

6. rotate to pick up position; and

7. extend grippers to next pipe section. The unload sequence moving pipe sections from the drill string to storage in the rack would be as follows: 1. rotate grippers to spindle center line;

2. extend grippers to grip pipe section to be removed from drill string;

3. rotate grippers and removed pipe section to the return position; and 4. retract grippers from pipe section in return position of rack. The pipe section will then fall by gravity to the pick up position through the S-curve path.

With reference now to FIGURES 3 and 4, a modified pipe rack 80 will be described. The pipe rack 80 includes a number of elements identical to pipe rack 16, including brackets 40 and 42, side plates 44 and 46, lifting eyes 48, apertures 50 and bars 60 and 62. It will be clear from this that pipe rack 80 can be mounted directly on the support frame 12 as a replacement for or substitute for the pipe rack 16 and pipe racks 16 and 80 are completely interchangeable.

Pipe rack 80 has an outer track 82, an intermediate track 84 and an inner track 86 mounted on the inside of each of the side plates 44 and 46. The pipe rack 80 defines a return position 104 and pick up position 96. A first vertical row 88 is formed between track 82 and track 84. A second vertical row 90 is formed between the intermediate track 84 and the inner track 86. A third vertical row 92 is formed between the inner track 86 and a guide 94 extending from the upper bracket 40 downward toward the lower bracket 42 and then forward to the pick up position 96 at the bottom front of the pipe rack. Block plates 98 are mounted on the plates to prevent pipe sections in the pipe rack from falling out because of gravity.

Manual upper row selectors 100 and 102 (seen in FIGURE 4) can be positioned to select which row a pipe section will enter after being placed in the return position 104. The manual upper row selectors 100 and 102 are located at each end of the pipe rack 80 at a pivot point 100c. Selector 100 selects the third vertical row 92 and rests, when in the receiving position (as seen in FIGURE 4) , on stop lOOd. Selector 102 selects the second vertical row 90 and rests on stop lOOe. The first vertical row 88 is selected by rotation of both manual upper row selectors 100 and 102 about pivot points 100c and into a position as shown at lOOf (where selector 102 is shown in FIGURE 4) . The top of the rack is open at the position of selectors 100 and 102 so that, for example, selector 100, seen in FIGURE 4 in the receiving position, can be pivoted clockwise about pivot 100c into position lOOf beside the position of upper row selector 102 seen in FIGURE 4. Both of the selectors 100 or 102 at each end of the pipe rack must be selected in order for the pipe to enter the desired vertical row. If selector 100 is selected at one end of the pipe rack and selector 102 is selected at the opposite end, the pipe will attempt to enter the second vertical row 90 and the third vertical row 92 simultaneously and become jammed. Preferably, as pipe sections are returned, the third row 92 will be filled up first, next the second row 90 and finally the first row 88.

Near the bottom of the pipe rack 80 are mounted gate rods 106 and 108 which extend the entire length of the pipe rack and are supported by the side plates for limited pivotal motion. Handles 110 and 112 (seen in FIGURE 3) are mounted on gate rods 106 and 108, respectively, to permit manual pivotal motion of the rods. Mounted along gate rod 106 are a pair of gates 114. In the position shown in

FIGURE 4, the gates 114 prevent pipe sections from moving out of the third row 92 into the pick up position 96. Gates 114 can be seen to have an arcuate end 116 to engage the lowermost pipe section in the third row. When the pipe sections in the third row 92 are to be used, the handle 110 is manually moved to pivot rod 106 so that the gates 114 move in a direction away from the block plates 98 (counter¬ clockwise in FIGURE 4) , permitting the pipe sections in the third row to fall onto the guide 94 for movement into the pick up position 96 by gravity. Gates 114 can be seen to have an actuate side 118 which assists the movement of the pipe sections to the pick up position.

Gate rod 108 similarly supports a pair of gates 120 which can be used to prevent pipe sections from the second row from moving into the pick up position 96. Gates 120 have a convex surface 122 which engages the pipe sections in either the second row or those pipe sections permitted to pass gates 114 from the third row to prevent the pipe sections from moving into the pick up position.

However, if pipe sections from the second or third rows are to be permitted to move to the pick up position, the handle 112 can be moved to pivot the rod 108 away from the block plates 98 (counterclockwise in FIGURE 4) to move convex surfaces 122 out of engagement with the pipe sections.

Gates 120 have actuate sides 124 to facilitate movement of the pipe sections by gravity into the pick up position.

Either handle 110 or 112 can be manipulated to stop supply of pipe sections from the second or third rows even before the rows have been emptied by moving the respective gate at least part way back to the blocking position until the pipe sections between the gates and the pick up position have been moved out of the pipe rack and then moving the gates to the final blocking position, as seen in FIGURE 4.

A number of rubber straps 126, as seen in FIGURES 4 and 4A, can be mounted within the pipe rack 80 to slow the fall of pipe sections within the rows to prevent pipe damage. The pipe rack 80 has the same volume of space as the pipe rack 16 but will carry a greater number of pipe sections. In operation, pipe sections are delivered to the return position 104 and directed by the manually positioned selectors 100 and 102 to one of the three vertical rows 88, 90, and 92. Gravity propels the pipe section to the bottom of the row. When removing pipe from the rack, the selection of a particular row to be used is accomplished by the manual rotation of the handles 110 and 112 as noted. The first row 88 connects directly with the pick up position 96 and has no gates associated therewith. After the pipe sections in the first row 88 are used, it is preferable to move handle 112 to permit the pipe sections in the second row 90 to next be used. Finally, the handle 110 is activated to allow the pipe sections in the third row 92 to be used. When all rows are emptied, the emptied pipe rack 80 can be off loaded from the support frame 12 and a full rack installed. The process is reversed when performing a backreaming or pullback function. FIGURE 5 is a cross-sectional view of a pipe rack

130 which is a modification of pipe rack 80. Pipe rack 130 is identical with pipe rack 80 with the exception of the use of gates 132 and 134 which each have convex ends 136 to engage the pipe sections in the second and third rows to prevent them from moving to the pick up position.

FIGURE 6 is a cross-sectional view of a pipe rack 140 which is a modification of pipe rack 80. In pipe rack 140, only two rows, rows 142 and 144 are used. This requires the use of only a single pair of gates 146 with convex ends 148.

FIGURES 5 and 6 permit the location of the positioning and gripper location in a new position or several different positions 150, 152, 154 in the case of FIGURE 5 and 156 and 158 in the case of FIGURE 6 to permit the loading and carrying of a greater number or quantity of drill pipe.

For the embodiment shown in FIGURES 3-6, the loading sequence to load pipe sections from the rack to the drill string would be as follows: 1. extend gripper to pick up position in rack; 2. pick up pipe section in pick up position; 3. retract grippers and gripped pipe section;

4. rotate grippers and gripped pipe section to spindle center line; 5. retract grippers after pipe section is threaded into drill string; and 6. rotate grippers to pick up position to pick up next pipe section. To remove pipe from the drill string and return it to the rack the unloading sequence would be:

1. rotate grippers to spindle center line;

2. extend grippers to grip pipe section to be removed from drill string;

3. rotate grippers and gripped pipe section to return position in rack; and

4. retract gripper from pipe section. The pipe sections will fall by gravity to the pick up position through the vertical rows.

With reference now to FIGURES 7 and 8 , an automatic pipe handling device 160 forming a second embodiment of the present invention is illustrated. The device 160 is mounted on drill rig 14 by bolting to a pair of brackets 162 on the drill rig frame. Plates 162, in turn, mount pipe rack brackets 166. A hydraulic motor 168 is bolted to the drill rig and rotates a longitudinal shaft 170 about an axis 172 which is parallel to the spindle axis 24. Mounted along the longitudinal shaft 170 are a pair of hydraulic cylinders 28 and 30 as used in device 10, including spring loaded pipe grippers with fixed fingers 33 and spring loaded fingers 35.

Each of the pipe rack brackets 166 can be seen to define an arcuate path 172 with a closed lower end 174 and an open upper end 176. The actuate path 172 and the pipe rack brackets 166 combine to form a curved row to receive and store pipe sections 18. In the particular case illustrated in FIGURES 7, 8 and 9, the pipe rack is capable of storing ten pipe sections.

As will be apparent from FIGURE 7, the hydraulic motor 168 is capable of pivoting the longitudinal shaft 170 to position the spring loaded pipe grippers at any selected position along an arc extending from a first position 178 for installing and retrieving pipe sections from the spindle axis 24 to a final position 180 where the pipe grippers are positioned to pick up the very last pipe section in the pipe rack.

With reference to FIGURE 7, if the operator begins with a full rack of pipe sections, the cylinders 28 and 30 are activated to retract the pipe grippers and the hydraulic motor 168 pivots the longitudinal shaft to position the pipe grippers in the pick up position 182 adjacent the first pipe section in the pipe rack. The cylinders 28 and 30 are then activated to extend the pipe grippers to grip the first pipe section in the pipe rack. The hydraulic motor 168 is then activated to pivot the longitudinal shaft 170 and pivot the pipe grippers and gripped pipe section into the first position 178, where the pipe section will be centered on the spindle axis 24 to be threaded into the drill string. Once threaded into the drill string, the cylinders 28 and 30 can be activated to retract the pipe grippers away from the pipe section. The hydraulic motor is then activated to pivot the longitudinal shaft 170 to position the pipe grippers adjacent the next pipe in the pipe rack. The pipe grippers will then be extended by cylinders 28 and 30 to grasp the next pipe and hydraulic motor 168 will be activated to move that pipe section into alignment with the spindle axis 24. As can be understood, the device will operate to remove each pipe section in sequence held on the pipe rack until the final pipe section at the final position 180 is delivered for insertion in the drill string.

As the drill string is being disassembled, the operation of the device 160 is simply reversed. The pipe grippers will grip the first section of pipe at the spindle axis 24 and can move it to the next open position along arcuate path 172 on pipe rack brackets 166 for storage before retracting the cylinders 28 and 30 to move the pipe grippers out of engagement with the pipe section. The operation will continue until all the pipe sections have been replaced in the pipe rack.

The loading sequence of operation for the device illustrated in FIGURES 7-8 will be for putting pipe sections in the drill string:

1. extend grippers to top most pipe section in rack;

2. pick up top most pipe section in rack;

3. rotate grippers and gripped pipe section to spindle center line to install in drill string;

4. retract grippers; and

5. rotate grippers to next top most pipe section in rack and repeat above sequence.

To remove pipe sections from the drill string and return them to the rack the unloading sequence would be:

1. rotate grippers to spindle center line;

2. extend grippers to grip pipe section in drill string to be removed;

3. rotate grippers and gripped pipe section to deposit the pipe section on top of the top most pipe section already in the rack, or the bottom of the path 172 if this is the first pipe section being returned;

4. retract grippers; and

5. rotate grippers to spindle center line to pick up next pipe section to be removed from the drill string.

With this device, the pipe sections are not dropped by gravity but are placed on top of the previously positioned pipe section or, if the first pipe section in the rack, at the bottom of the path 172. It will be appreciated that the adjustment plates

164 have elongated bolt holes 184 which will permit some adjustment of the position of the pipe rack brackets 166 relative to the drill rig 14 and the spindle axis 24. As seen in FIGURES 8 and 9, a stow lock 187 is pivotally mounted on each of the pipe rack brackets and can be pivoted over the open upper end 176 of each bracket and pinned in that position by pins 188. This will prevent inadvertent removal of the pipe sections during transport of the drill rig. -

The hydraulic motor 168 does not specifically index the pipe grippers to any pick up position or return position. The pipe sections are, however, picked up from the top of the pipe rack brackets near the open upper end 176 to the bottom of the pipe rack brackets near the closed lower ends 174 in sequence and are returned in opposite order. It is preferable to move the pipe section along the arcuate path 172 and into contact with the next adjacent pipe section in the rack before removing the grippers to avoid allowing the pipe sections to fall by gravity along the arcuate path.

The device of the present invention can be operated by a single individual with only two controls. The first control will operate the hydraulic drive motor 26 or 168 and the second control will operate the hydraulic cylinders 28 and 30 to grab the pipe sections with the pipe grippers 32. The device therefore permits the operator to automatically move drill pipe from the pipe rack carried on the boring device to the spindle center line as the drilling progresses. After completion of the pilot bore and while backreaming and pulling back services, the device will automatically unload the drill pipe from the spindle center line and return the drill pipe to the pipe rack. By designing the pipe racks to be readily installable on and removable from the support frame 12, as many pipe sections as required can be quickly provided. This design permits the number of people in an operating crew for the boring machine to be reduced from three to two.

The device also improves the function, productivity and safety of the drill rigs used by the guided boring industry. The operator, by moving two hydraulic valve levers, has complete control of the pipe loading and unloading operation. The device is easily understood and easy to operate. The operator can remain at the console to operate the device. The smoothness of the operation permits the operator to load and unload drill pipe at the spindle very efficiently. This improved smoothness and efficiency results in less time spent adding to and removing drill pipe from the drill string, -thus reducing time spent on the job. The mechanical device removes the need for another person on the crew to remove drill pipe from a pipe box and load or unload at the spindle. The safety aspects of the device remove the possibility of injury by eliminating the need to lift and load the drill pipe by hand and eliminating the need for an additional crew member to lift and load the drill pipe.

With reference now to FIGURES 10-21, a pipe handling device 200 forming another embodiment of the present invention is illustrated. With reference to FIGURES 14-16, the device includes a pipe box 202 for storage of pipe sections 18. Pipe box 202 is mounted to the drill rig 14 at mounting points 204 and 206 so that the elongate axis 208 of the pipe box is parallel to the spindle axis 24. The pipe box includes a rectangular bar 210 with bottom plates 212 mounted thereon near each end of the bar. Side plates 214 and 216 extend upwardly from either side of the bottom plates and an end plate 218 connects the upper ends of the side plates at each end of the box. Preferably, corner plates 220 (FIGURE 16) are mounted between the bottom plate and each of the side plates, as seen in FIGURE 16. The distance X between the side plates is sufficient to accommodate a number of pipe sections 18 side by side, for example, three or four. The pipe sections are preferably stored in a stack determined manner. For example, the lowest row may be three pipe sections side by side. The next or second row on top will be four pipe sections wide, with the outer pipe sections of the second row naturally fitting between the side walls and the outer pipe sections just below in the lowest row. The inner pipe sections on the second row naturally fit between adjacent pipe sections in the lowest row. The third row would then be three pipe sections wide, fitting between adjacent pipe sections in the second row. Such a configuration is illustrated in FIGURE 16. Simply put, as a pipe section is placed in the pipe box on pipe sections already there, it will naturally pick a stable position nested between adjacent pipe sections in the next lower row or between a side wall and the pipe section adjacent the side wall in the next lower row. The height Y of the box is sufficient to accommodate a number of pipe sections vertically, for example, eight. In one embodiment, the pipe sections are held in alternating rows of three and four pipe sections from the bottom to the top of the box along the Y direction. The pipe sections can enter and leave the box through the top of the pipe box between the side plates and end plates. The side plates prevent the pipe sections from rolling out of the box. The bottom plates support the lowest row of pipe sections. Typically, the pipe sections used will be of a type having upset ends, that is ends that have a larger diameter than the intermediate portions of the pipe sections, providing sufficient space between each pipe section for the pipe section to be gripped in a manner discussed hereinafter.

As seen in FIGURE 21, removable end panels 219 at either end of pipe box 202 normally hold the pipe sections from falling out the ends of the pipe box, but can be removed by lifting out retaining pin 221 to allow access for removal of thread and dust protective caps (not shown) typically installed on the ends of each pipe section 18. The bottom end panel 219, for the lower end of pipe box 202 when it is installed on an inclined boring unit 14, is offset and reversible. Once reversed, the offset restrains the pipe sections 18 from sliding down toward the lower end of box 202 after the protective caps are removed. When the bore is completed and the pipe box 202 is ready for transport from the job site, the end panels can be removed for installation of the protective caps. Bottom panel 219 is now reversed to its original (storage) position to clear the added length of the protective caps.

With reference to FIGURES 10-13, the device 200 also includes a pipe loader 222 which is mounted on top of the pipe box 202 and secured thereto. The pipe loader includes a rear pivot mount 224 and a front pivot mount 226. With reference to FIGURES 14 and 17, pivot mount 224 can be seen to have vertical rods 228 at each side thereof which extend downwardly and are received within sockets 234 mounted on side plates 214 and 216 at the rear of the pipe box. Similarly, the front pivot mount has rods 232 which mount through sockets 230 on the side plates 214 and 216 at the front of the pipe box.

A rotation member 236 is mounted between the pivot mounts 224 and 226 to pivot about pivot axis 238 which, when the pipe box 202 is mounted on the drill rig, and the pipe loader 222 is mounted on the pipe box, is also parallel the spindle axis 24. Mounted along the rotation member 236 are a pair of lifting eyes 240 which permit the pipe loader 222 to be lifted off of the pipe box. It is preferable to do so before the pipe box is detached from the rig.

Also mounted on rotation member 236 are a pair of cylinder mount tubes 242 which each mount a double acting extension cylinder 244. A pair of guide tubes 246 are also mounted on the rotation member and receive the guides 248 of an extension frame 250. The ends of the pistons of extension cylinders 244 are mounted to the extension frame at points 251. At each end of the extension frame is mounted a pipe gripper 256 which includes a fixed finger 258 and pivoting finger 260. The finger 260 is pivoted by the piston of a double acting gripper cylinder 262. The cylinder 262 is supported on the extension frame 250 at the outer ends of the cylinder supports 252 and 254 mounted to frame 250.

With reference to FIGURES 17-20, the rear end of the rotation member 236 has a pair of stop pins 264 mounted thereon. A pivot adjustment stop 266 is mounted to the rear pivot mount 224 by bolts. The bolt holes 267 in the stop allow for limited pivotal motion about the axis 238 before tightening the bolts. The pivot adjustment stop has stop surfaces 268 and 269 which engage the stop pins 264 to confine the pivotal motion of the rotation member to a predetermined angle, for example 65 degrees.

A double-acting pivot cylinder 270 is pivotally mounted to the rear pivot mount 224 on pivot 272. The piston 276 of cylinder 270 is pivotally mounted to one end

277 of a rotation arm 278. The other end of rotation arm

278 has a pin 279 extending in the end of rotation member 236 which is secured to the end of the rotation member 236 by a key. Thus, extension and retraction of the piston 276 within the cylinder 270 will cause pivotal motion of the member 236 between the limits permitted by the pivot adjustment stop 266.

With reference to FIGURE 13, the hydraulic connections in the pipe handling device 200 can be described. The hydraulics will normally be powered from a hydraulic pump on an accessory power system (not shown) , but can be powered from another source. Also, hydraulic operation can be replaced by compressed air operation or other suitable drive mechanism. A control valve assembly 280 is provided which includes at least three control valves 282, 284 and 286 controlled respectively by control handles 288, 290 and 292. Valve 282 is connected through lines 294 and 296 to the double-acting rotation or pivot cylinder 270. The lines 294 and 296 pass through a check valve unit 298. Thus, activation of the handle 288 in opposite directions will cause the piston of cylinder 270 to extend and retract, pivoting the rotation member with the pipe grippers mounted thereon. When the rotation member has been pivoted to the desired position, the check valve 298 will maintain the member in that position when the handle is released.

Lines 300 and 302 extend from the valve 284 to the double-acting extension cylinders 244 to extend or retract the extension frame 250 relative the rotation member 236. A check valve 304 is utilized to maintain the position of the extension frame 260 after lever 290 is released. A flow divider 306 is preferably utilized to insure uniform motion of the pistons in the cylinders 244 so that the extension frame 250 does not jam as it is moved relative the rotation member 236.

Lines 308 and 310 extend from the valve 286 to the gripper cylinders 262. Thus, activation of the handle 292 will alternatively open the grippers or close -the grippers about a pipe section. A check valve 312 maintains the position of the grippers when the handle is released.

The pipe handling device 200 enables the operator to move pipe joints or segments from the pipe box 202 to the drill unit for the purpose of adding pipe segments to the drill string as the boring operation progresses. Once the initial boring process or pilot bore is complete, the pipe handling device 200 enables the operator to sequentially remove pipe from the drill string and return it to the pipe box 202.

When boring or drilling the initial pilot hole with the drill unit, the operator must sequentially add more drill pipe segments to the drill string as it advances in the ground. This involves operations known in the art such as drilling forward, breaking connection with the drill string, retracting the drill unit carriage, adding another pipe segment to the drill string, and resuming the boring process. The pipe handling device 200 assists in the operation of obtaining and positioning the added pipe segments so that it can be threaded into the drill string. Once the bore is completed, the pipe handling device 200 assists in the operation of moving the pipe segments back to the pipe box.

In the drilling process, to load another pipe, the operator operates the three valves 282, 284 and 286 in sequence or in combination. The pivot cylinder 270 is used to rotate the rotation member and pipe grippers toward the desired pipe section in the pipe box. The extension cylinders 244 are used to telescope the extension frame 250 with the pipe grippers toward the selected pipe segment within the pipe box. The gripper cylinders 262 are actuated to close the gripping fingers 258 and 260 around the selected pipe section. The device can grasp any pipe section in the top row of the pipe box, although the operator will generally choose the one most accessible, typically the one closest to the drill unit. The stroke of extension cylinders 244 will be long enough to grasp pipe sections at the bottom of the pipe box. Once the pipe section is gripped, it is moved above the pipe box by a combination of rotation of the member 236 by the pivot cylinder 270 and retraction of the extension cylinders 244 so that the pipe section at least clears the top of the side plates. With the pipe section now above the pipe box, the pivot cylinder 270 is actuated to pivot the rotation member into alignment with the spindle axis 24. This alignment can be set by the pivot adjustment stop 266. Assuming the drill unit is ready to receive another pipe section, the operator can extend the extension cylinders 244 to move the gripped pipe section into coincidence with the spindle axis 24. The operator then moves the carriage of the drill unit forward so that the spindle engages the top hole end of the pipe section and begins to rotate the spindle to thread the connection together. Then the spindle is advanced, sliding the pipe section through the grippers to engage the other end of the pipe section with the drill string, and make that connection. The gripper cylinders 262 are then actuated to release the pipe section and the extension cylinders are actuated to move the extension frame 250 away from the installed pipe section. The pivot cylinder 270 can then pivot the rotation member 236 to pick up the next pipe section in the pipe box. If the bore is longer than the amount of pipe in the pipe box, the pipe loader 222 can simply be released from and lifted off the empty pipe box and a loaded pipe box is substituted. The pipe loader 222 can then be lowered onto and secured to the full pipe box to continue the drilling operation.

The unloading process is essentially the reverse of the loading process. The pipe box will be at least partially empty. The carriage on the drill unit is moved back to pull the drill string from the hole, and the first pipe section in the drill string is broken free of the string. The pipe handling device 200 is positioned so that the pipe grippers 256 will engage that pipe section. This engagement can be done before the threaded connections are broken or after. The carriage is moved back enough to disengage the bottom threads of the pipe section, if necessary, sliding the pipe section through the grippers a short distance. The spindle is further rotated and retracted to disengage from the top end of the pipe section. Then the operator can move the pipe section back to the pipe box in the reverse motion from installation. This is done first by retraction of the extension cylinders 244 and followed by actuation of the pivoting cylinder 270 to pivot the rotation member and suspend the pipe section above the pipe box. The extension cylinders 244 are then extended to lower the pipe section into the box to the position selected by the operator. The gripper cylinders 262 are actuated to release the pipe section and the pipe will drop in place within the box as determined by the stack of pipe already there. Preferably, the operator will not drop the pipe from too high above the existing stack of pipe so that the released pipe section does not become diagonally wedged inside instead of conforming to the stack. The process continues until the last pipe section has been withdrawn from the borehole.

In pipe handling device 200, the operator is involved in the process of deciding which pipe to pick up and where to return it. The operator also has to exercise judgment on how far to extend the extension cylinders 244 in order to line up the pipe with the spindle axis, although rotation to that position with the pivoting cylinder is controlled by the pivot adjustment stop 266. Thus, the device is less of an automatic pipe handling device and performs primarily as a mechanical aid to reduce the manual labor involved in the drilling process. The pipe handling device 200, while disclosed to be mounted on the drill unit, could be supported separately from the drill unit. Further, the pipe loader 222 can, itself, be supported separately from the pipe box 202. For example, pipe handling device 200 might be mounted on a pipe trailer positioned next to the drill unit. One can also appreciate that there are multiple ways to implement the rotation and extension/retraction actions performed by cylinders 244 and 270. For example, the two extension cylinders 244 can use the flow divider 306 to cause them to extend equally. This could be accomplished with a pair of timed ball screws, rack and pinion or the like.

In addition, supports can be mounted on the drill unit itself to receive the pipe sections from pipe handling device 200. These supports would be positioned on the spindle axis to align the pipe section directly. These can be configured to swing away or retract when the carriage on the drill unit advances in the drilling process. This would make alignment of axes 24 and 238 less critical and facilitate mounting the device 200 or loader 222 separate from the drill unit.

Among the significant advantages of pipe handling device 200 is its ability to pick up and return a pipe section to any location within the pipe box. The pipe loader 222 is also easily movable from one pipe box to another, an important factor when longer distance boreholes are drilled. Pipe loader 222 can also be used independently of pipe box 202 if a source of pipe sections within reach of the pipe grippers is provided. Further, the pipe handling device 200 lends itself to retrofitting on older drill units already in service. Also, the use of the pivot adjustment stop 266 insures that the extension of cylinders 244, occurring in a single plane approximately intersecting and parallel to the spindle axis 24 means that the operator need only operate this single function to achieve alignment with the spindle axis. This makes the process easier to accomplish. Typically, the extension cylinders will have to have sufficient capability to extend further than the spindle axis because this extended reach is necessary to reach the bottom row of pipe sections in the pipe box.

Although the present invention has been described with respect to a specific preferred embodiment thereof, various changes and modifications may be suggested to one skilled in the art, and it is intended that the present invention encompass such changes and modifications as fall within the scope of the appended claims.

Claims (24)

1. A pipe handling device for moving a pipe section from a pickup position to a spindle center line position on a drill rig, comprising: a pipe box holding a plurality of pipe sections at stack determined positions in the interior of the pipe box, the elongate axis o£ each of the pipe sections being parallel the spindle center line; a pipe loader having a member for pivotal motion about an axis generally parallel to the spindle center line; and at least one pipe section gripper extending from the member to grip a pipe from within the pipe box for movement to the spindle center line position, the pipe loader permitting an operator to select a particular pipe section to be removed from the pipe box.

2. The pipe handling device of Claim 1 wherein the pipe loader is mounted on the pipe box, the pipe loader having a member mounted for pivotal motion relative to the pipe loader about an axis generally parallel to the spindle center line.

3. An automatic pipe handling device for moving a pipe section from a pick up position to a spindle center line position on a drill rig, comprising: a support frame mounted on the drill rig; a member pivotally mounted to the support frame for pivotal notion about an axis generally parallel the spindle center line between a first position and a second position; and at least one pipe section gripper extending from the member to grip a pipe section, the gripper gripping the pipe section in the pick up position when the member is in the first position and gripping the pipe section in the spindle center line position when the member is in the second position.

4. The automatic pipe handling device of Claim 3 further comprising a pipe rack mounted on the support frame, the pipe rack indexing pipe sections to the pick up position.

5. The automatic pipe handling device of Claim 4, wherein the pipe rack further has a return position, the member pivotally movable to a third position to return a pipe section to the return position, the pipe section falling by gravity from the return position to the pick up position in the pipe rack.

6. The automatic pipe handling device of Claim 3 further comprising a hydraulic motor to pivot the member.

7. The automatic pipe handling device of Claim 5, wherein the pipe rack supports pipe sections along a curved path, and the pipe sections are preferably placed in position along said curved path by the grippers and not allowed to fall by gravity.

8. The automatic pipe handling device of Claim 5, wherein the pipe rack supports pipe sections in a plurality of generally vertical rows.

9. The automatic pipe handling device of Claim 5, wherein the pipe rack supports pipe sections in an S-curve path.

10. The automatic pipe handling device of Claim 8 further including a gate mounted on the pipe rack to prevent at least one row of pipe sections from moving to the pick up position.

11. The automatic pipe handling device of Claim 3, further including a hydraulic cylinder having a piston, said pipe gripper mounted on the piston of the hydraulic cylinder, the hydraulic cylinder being mounted on the member for moving the pipe gripper between a retracted position and an extended position.

12. The automatic pipe handling device of Claim 4, wherein the pipe rack is removably mounted to the support frame.

13. The automatic pipe handling device of Claim 11 wherein the pipe rack is mounted to the support frame by removable pins.

14. An automatic pipe handling device for moving a pipe section to and from a spindle centerline position on a drill rig, comprising: a support frame mounted on the drill rig; a longitudinal shaft pivotally mounted to the support frame for pivotal motion about an axis generally parallel the spindle centerline; first and second pipe grippers mounted on the longitudinal shaft, each pipe gripper for motion between a retracted position and an extended position along a direction perpendicular the pivotal axis of the longitudinal shaft; a pipe rack mounted on the support frame, the pipe rack storing pipe sections, the pipe rack having a pick up position, pipe sections in the pipe rack being indexed to the pick up position by gravity, and a return position; and a motor mounted on the support frame for pivoting the longitudinal shaft.

15. The automatic pipe handling device of Claim 13 wherein the pipe rack is removable from the support frame.

16. The automatic pipe handling device of Claim 13 wherein the pipe rack is an open-sided box, a pair of guide tracks or end guides being mounted in the pipe rack to guide the pipe sections and indexed by gravity from the return position to the pick up position.

17. The automatic pipe handling device of Claim 15 wherein the guide tracks define an S-curve path.

18. The automatic pipe handling device of Claim 15 wherein the guide tracks define a plurality of generally vertical rows.

19. The automatic pipe handling device of Claim 17 wherein the pipe rack includes at least one pivotal shaft mounted therein having a pair of gates to block pipe sections from one of said rows from moving to the pick up position.

20. The automatic pipe handling device of Claim 13 wherein the pipe rack has at least one block plate to hold the pipe section in the pick up position.

21. A method for moving pipe sections to and from a spindle centerline position on a drill rig for installation in or removal from a pipe string to form an automatic pipe handling device, comprising the steps of: mounting a support frame on the drill rig; pivoting a longitudinal shaft mounted on the support frame for pivotal motion about an axis generally perpendicular the spindle centerline to a first position; extending a pipe gripper element mounted on the longitudinal shaft to grasp a pipe section located at a pick up position in a pipe rack; retracting the pipe gripper element to remove the pipe section from the pipe rack; pivoting the longitudinal shaft to a second position; extending the pipe gripper element to position the pipe section on the spindle centerline; retracting the pipe gripper element from the pipe section positioned on the spindle centerline for installation in the pipe string.

22. The method of Claim 20 further comprising the steps of: extending the pipe gripper element with the longitudinal shaft in the second position to grip the pipe section along the spindle centerline; retracting the pipe gripper element to move the pipe section out of the spindle centering; pivoting the longitudinal shaft to a third position; extending the pipe gripper element to position the pipe section in a return position on the pipe rack; and removing the pipe gripper element from the pipe section to permit the pipe section to fall by gravity within the pipe rack to be indexed at the pick up position.

23. The method of Claim 20 further comprising the step of actuating a hydraulic control to control a hydraulic motor pivoting the longitudinal shaft.

24. A pipe handling device for moving a pipe section from a pickup position to a spindle center line position on a drill rig, comprising: a pipe box holding a plurality of pipe sections at stack determined positions in the interior of the pipe box, the elongate axis o£ each of the pipe sections being parallel the spindle center line; a pipe loader mounted on the pipe box, the pipe loader mounting a member for pivotal motion relative to the pipe loader about an axis generally parallel to the spindle center line; and at least one pipe section gripper extending from the member to grip a pipe from within the pipe box for movement to the spindle center line position, the pipe loader permitting an operator to select a particular pipe section to be removed from the pipe box.