|Publication number||US3670831 A|
|Publication date||Jun 20, 1972|
|Filing date||Dec 31, 1970|
|Priority date||Dec 31, 1970|
|Publication number||US 3670831 A, US 3670831A, US-A-3670831, US3670831 A, US3670831A|
|Inventors||Foss Richard L, Williams Arthur M Jr, Winter Henry A Jr|
|Original Assignee||Smith International|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (3), Referenced by (17), Classifications (17)|
|External Links: USPTO, USPTO Assignment, Espacenet|
United States a Patent Winter, Jr. et al. [451 June 20, 1972  EARTH DRILLING APPARATUS 3,158,213 v 11/1964 O'Neill =1 al ..175/85 Inventors: Henry A. win", Denver; r M. 3,266,582 8/1966 Homamck ..175/85 X Williams, Jr., Lakewood; Richard L. Foss, Prim), Examiner Emest Purser Denver of Colo Attorney-Sheridan, Ross and Burton  Assignee: Smith international, Inc., Newport Beach,
Calif  ABSTRACT 22 F} d: be 31 1970 Earth drilling apparatus characterized by a wheel supported I 1 vehicle having a pivoted derrick or mast which is movable  Appl. No.: 103,183 between substantially horizontal and vertical positions, thepivotal movement of the mast being utilized to transfer horizontal drill pipe, stacked vertically in a stationary  US. Cl ..175/52, 173/28, 173/164, magazine, to a rcciprocable drilling head carried by the mast 175/85 The pipes in the magaa'ne are incrementally moved vertically [51 Int. Cl .1521!) 19/ 14 to align the uppermost drill pipe therein with the drilling head  Field of Search "175/52, 85; 173/28, 164; and a releasable tong device is emp|oyed to secure the drill 166/775, 315; 2l4/2.5 pipe to the mast in fixed relation thereto during raising and lowering of the mast.  References Cited 10 Claims, 7 Drawing; figures UNITED STATES PATENTS 2,960,311 11/1960 Scott ..l73/28 X 72" 5 8 1: /72 i: 1* '11 'as-- e2 812 FATENTEDmzo m2 SHEET 10F IN VENTORS HENRY A. WINTER, JR. ARTHUR M WILLIAMS, JR. RICHARD L. FOSS BY &,&
ATTORNEYS PATENTEDJum I972 sum 2 nr 3 INVENTOR'S HENRY A. WINTER, JR. us ARTHUR M. WILLIAMS, JR.
BYZ I .M/
ATTORNEYS PA'TENTl-imunzo 1972 3.670.831
INVENTORS HENRY A. WINTER, JR. ARTHUR M WILLIAMS, JR. RICHARD L. FOSS ATTORNEYS EARTH DRILLING APPARATUS BACKGROUND OF THE INVENTION In the drilling of holes in the earth it is common practice to mount a drill derrick or mast on a vehicle which may be readily moved to the drill site. The mast, which is disposed in a generally vertical position during the drilling operation, is usually pivoted near its lower end to the vehicle for movement to a generally horizontal position when the vehicle is being transported over a road or other terrain so that it may clear overhead obstructions, lower the center of mass of the vehicle, and more securely affix the mast to the vehicle during its movement. Since a drill string is conventionally formed of sections of drill pipe of predetermined length detachably connected together with threaded joints or the like, it is also conventional practice to provide the apparatus with some form of drill pipe magazine containing the sections from which they may be sequentially removed as the drilling progresses in depth. Similarly, when the sections are removed from the drill hole they are sequentially returned to the magazine. Various forms of magazines and drill pipe transfer apparatus have been devised to effect the drilling as above outlined. For example, in US. Pat. No. 2,972,388 to Thomberg, a rotary magazine is carried by the mast and is sequentially indexed so that a drill pipe therein may be aligned with a drill pipe drilling head rectilinearly movable along the mast. In this form of apparatus the mast remains in its erect position during the. enu're drilling operation. In another form, as exemplified by US. Pat. No. 3,158,213 to ONeill et al., the mast also remains erect and mechanism is provided for transferring a single horizontal pipe to the vertical mast. As will be apparent, if it is desiredto transfer more than one pipe from the horizontal position, apparatus, such as a crane, or the like, must be employed to replenish the pipe removed from the horizontal position.
SUMMARY OF THE INVENTION The present invention bears some similarity to the prior art referred to and is probably the most similar to US. Pat. No. 3,158,213. In its broader aspects it differs essentially in that a magazine of stacked horizontal pipes is provided, the mast is sequentially pivoted to horizontal position at which position the uppermost pipe in the magazine is affixed to the drilling head, and elevating mechanism is provided for sequentially raising the stack so that the uppermost pipe therein is disposed in axial alignment with the drilling head. In like manner, when the string is removed from the drilled hole, the mast is sequentially oscillated between its erect and lowered positions and the drill pipes returned to the magazine. After a pipe is returned to the magazine, the pipes therein are incrementally lowered to accommodate the next pipe returned to the top of the stack.
During the raising and lowering of the mast it is important that the pipe be suitably supported by the mast so that no relative motion occurs therebetween which would produce undesired stresses on the drilling head. A releasable tong is provided for this purpose which grasps the pipe between its ends and rigidly secures it to the mast while being erected or lowered. When the mast is moved to a predetermined erect position the lower end of the drill pipe is thus in proper alignment with the drill hole. The tong is then released to permit the drilling head to rotate the pipe.
The mast briefly described above is preferably mounted centrally on the front end of a high speed wheel supported vehicle adjacent a control cab from which the vehicle motion may be controlled and the drilling operation also controlled by a single operator in the cab. Also, all wheels are preferably power driven and the rear wheels, as well as the front wheels, are steerable. A single internal combustion engine provides power for driving the vehicle and also for driving apparatus employed during drilling which includes a power transfer box for either the wheels or instrumentalities, such as hydraulic pumps and an air compressor. Reversible hydraulic motors are employed for rotating the drilling head and translating it along the mast.
The utility of the apparatus resides principally in drilling relatively shallow holes, such as blast holes which require a string of only several sections of drill pipe. Any depth, however, may be drilled by replenishing the magazine during the drilling operations when the mast is erect.
The principal object of the invention, consonant with the foregoing, is the provision of an earth drilling vehicle provided with a pivoted mast, the pivotal motion of which is utilized to transfer horizontal drill pipe in a magazine to a vertical position.
Another object is to secure a drill pipe to the mast, against motion relative thereto, while the mast is being raised or lowered.
Further objects, advantages, and salient features will become more apparent from the detailed description to follow, the appendedclaims, and the accompanying drawing, to now be briefly described.
BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a side elevation of the subject of the invention, portions being broken away and some details omitted;
FIG. 2 is a rear elevation as viewed in the direction of arrow 2, FIG. 1, the mast being shown in elevated position and a por- Y FIG. 6 diagrammatically illustrates hydraulic raising and I lowering apparatus for the magazine; and
FIG. 7 is a modification of a portion of FIG. 3.
DESCRIPTION OF PREFERRED EMBODIMENTS Vehicle and Auxillaries Referring nowto the drawing, and first to FIGS. 1 to 4, vehicle 10 comprises a frame 12, supported by a pair of steerable front wheels 14 and a pair of rear wheels 16 which are also preferably steerable to enable the vehicle to be maneuvered about a relatively small turning radius. Frame 12 supports a conventional internal combustion engine 18 coupled by a releasable clutch 20 to a pair of tandem selective speed transmissions 22, 24. The output shaft 26 of transmission 24 forms the input shaft to a transmission transfer box 28 which contains a tubular jack shaft 30 chain or gear connected to shaft 26. A two position splined positive or dog clutch 32 constantly rotates with jack shaft 30 and may be selectively engaged with wheel drive shaft 34 or an accessory drive sprocket 36 journaled on shaft 30. Sprocket 36 is chain connected to two output shafts 38, 40 which drive hydraulic pumps 42, 44, respectively. Sprocket 36 is also connected by the same chain to a larger sprocket 46 forming a speed reducer. The latter is connected through a disengagable clutch ,48 to an air compressor 50. When clutch 32 is connected to sprocket 36 the two hydraulic pumps are constantly driven and the air compressor may optionally be driven therewith through clutch 48. When clutch 32 is shifted to its other position, the pumps and air compressor are disconnected and the drive is through shaft 30 to shaft 34 which drives the front wheels. When clutch 52 is also connected to shaft 34 the rear wheels are also driven through shaft 54. Thus, during motion of the vehicle, all wheels may be driven or only the front wheels may be driven. A pair of hydraulic jacks 56, one at each side of the frame near its front end, and a jack 58 disposed centrally of the frame at its rear end, provide three pointleveling supports to orient the vehicle relative to the hole to be drilled and which provide a firm support, taking a portion of the vehicle weight off of the wheel suspension springs.
An enclosed cab 60 is disposed at the front end of the vehicle at one side of its central longitudinal axis which contains all controls for maneuvering the vehicle and all controls for operating the drilling instrumentalities. As will be apparent, it is provided with suitable windows to enable an operator therein to maneuver the vehicle or observe the drilling operation from an operators seat therein. Mast The mast or derrick 62 comprises a pair of parallel upper structural members 64, 64 connected by transverse and angular members 66, 68 (FIG. 2), and a pair of parallel like lower members 70, 70 connected in like manner to form a U-shape beam or truss which is open at its lower side to permit it to be pivoted to a position wherein the magazine, to subsequently be described, is disposed within the cross sectional space formed by the various members. Parallel channel shaped guide members 72, 72 are secured to the two parallel legs of the U, forming parallel facing guides along which drilling head 74 may translate. A plate 76 is secured to each of the legs of the U at the lower forward end thereof which is secured to the vehicle by a pivot pin 78. A pair of double acting hydraulic actuators 80, 80 are each pivotally connected at one end to the vehicle frame and at the other end to plate 76. As will be apparent, when the actuators are extended or retracted the mast may be moved between the horizontal and vertical positions. Drilling Head The drilling head 74 is provided with suitable rolls 82 which move along the guides during a drilling operation. The drive shaft or spindle 84 is hollow and its upper end swivelly connected to an air supply conduit which is connected by a flexible hose (not shown) to the air compressor. The lower end of the drive spindle is provided with a suitable chuck or coupling, such as a tapered conventional male drill coupling thread with a shoulder adjacent same, which is detachably connected to a like female thread in one end of the drill pipe. The coupling is preferably detachable from the drive spindle so that it may be replaced with other like couplings of various sizes for various size drill pipe or with other suitable couplings. A drive motor carried by the head is of the reversible variable speed type and is operated by high pressure liquid delivered through a hose (not shown) by one of the hydraulic pumps previously referred to. Pull-Down The translating or pull down mechanism for the head comprises a pair of chains 86, 86, each connected at an end of same to the head, preferably through compression buffer springs 88. The chains are trained about laterally spaced idler sprockets 90 to drive sprockets 92 carried by a shaft which is rotated by a variable speed reversible hydraulic motor 94 which is hose connected to one of the hydraulic pumps. Cables 96 are connected to opposite ends of the chains and trained about sheaves 98 in crown block 100. As will be ap parent, when pull down motor 94 is actuated in one direction the chains pull down the head during drilling and when operated in the opposite direction the cables return the head to its upper position adjacent the crown block. Magazine The magazine comprises at least two longitudinally spaced U-shaped fixed saddles 102 in which drill pipe may rest in a vertical stack. A hydraulic lifting jack or ram 104 is disposed beneath each saddle, these being operated simultaneously to lift the stack so that the uppermost pipe therein is axially aligned with the drilling head spindle. When so aligned, a tong, to be described, grasps the pipe at a point remote from the spindle, preventing its rotation and supporting it rigidly relative to the mast. The drilling head is then translated and rotated to connect its spindle to one end of the pipe. The mast is next elevated to its desired upright position after which the tong may be released from the pipe, preparatory to drilling. Mast Pipe Holding Tong Tong 106 (FIGS. 1 and comprises an arm 108 pivotally connected at its upper end to the bight portion of the U- shaped mast and centrally between the legs thereof and movable upwardly and rearwardly as indicated by arrow 110 by a hydraulic actuator 112. Its lower end pivotally carries jaws 114 provided with levers 116 between which is pivotally connected by a double acting hydraulic actuator 118 which may close the jaws on a pipe or release same therefrom. Assuming that the mast has returned to its horizontal position without a pipe carried by same, am 108 is now in its upper position with the jaws open. The pipes in the magazine are then raised by one pipe diameter by actuators 104 so that the uppermost pipe is in alignment with the drilling head. Arm 108 is then moved to its lower position by actuator 112, as shown in FIG. 1, and
the jaws are moved to their clamping position with the pipe. The drilling head is then translated toward the other end of the pipe and its spindle rotated to threadedly connect it thereto. The mast is then elevated to its erect position preparatory to drilling.
Pipe Guide and Clamping Dog A lower pipe guide and clamping dog assembly 120 (FIG. 3), which may be of conventional construction, is affixed to the front end of the vehicle, the clamping dogs (not shown) of which may be opened and closed by a double acting hydraulic actuator 122. The assembly is pivotally mounted for limited rotation about a vertical axis and is rotated by a double acting hydraulic actuator 124. When a pipe is disposed in the mast and clamped by tong 106, previously described, the dog assembly may be closed to engage the upper end of the adjacent lower pipe after which actuator 124 is operated, serving as a wrench to break the threaded and shouldered connection between the adjacent pipes. After the joint is broken loose the tong may then be released and complete separation effected by rotating the drilling head in the opposite direction to that in which it rotates during drilling, after which the tong may be reengaged with the pipe to support one end of same during return of the mast to its horizontal position. After the pipe has been redeposited in the magazine the mast is then elevated and the drilling head lowered to engage the pipe secured to dog assembly 120. The dog assembly is then released and the drilling head is moved to its uppermost position, lifting the next pipe from the drilled hole, after which the procedure is repeated until all pipes have been removed from the hole. Hydraulic System FIG. 6 diagrammatically illustrates the essential elements of the magazine raising and lowering apparatus. Cylinders are of the same diameter, the lower ends of which communicate through shut-ofl' valves 132 with identical charge cylinders 134 which contain pistons 136 having piston rods 138 which may engage adjustable stops 140 which adjust the stroke of the pistons and hence the volumes in charge chambers 142. A charge valve 144 is connected between pump 42 and both charge chambers 142 through a pair of three-way valves 148. Actuating chambers communicate with pump 42 through a three-way cycle valve 152 which, in one position, communicates with the reservoir as indicated by a dotted arrow.
In the operation of the apparatus just described, it will first be assumed that the drill pipe in the magazine is to be raised, the piston rods are against their stops and the lock valves are closed. The lock valves are now opened and cycle valve 152 is moved to a position to communicate the pump with actuating chambers 150. Pistons 136 then move through their strokes,
delivering equal volumes of liquid to lift cylinders 130 raising their rams 104 equal increments, which as previously referred to, is one pipe diameter. The lock valves are now closed, cycle valve 152 is moved to reservoir communication and charge valve 144 opened to return the charge pistons to their stops, thus replenishing chambers 142 preparatory to again raising the pipes one increment. As will be apparent, this operation continues until it is desired to return the pipes to the magazine, which will now be described.
At the commencement of return, let it be assumed that pistons 136 are disposed at the upper ends of their strokes. The lock valves are now opened and the cycle valve 152 is moved to sump communication as indicated by a dotted arrow. Pistons 136 descend, filling charge chambers 142. The lock valves 132 are then closed, valves 148 are opened to sump communication and the cycle valve opened to move the charge pistons to the upper end of their strokes, returning the liquid therein to the sump. This procedure is repeated in like manner until all of the desired pipes are returned to the magazine.
The purpose of adjustable stops M0 is to provide various volumes for chambers M2 to thereby vary the incremental lifts of lift pistons or rams 104 since various diameters of drill pipe may be used with the apparatus by suitable selection of the size of saddles 102. Thus, if stops 140 are set to move 3% inch drill pipe one diameter and it is desired to use 4-inch drill pipe the incremental lift must be increased one-half inch. This is effected by setting the stops so that the volume of chambers 142 is increased to effect the required 4-inch lift or descent.
Pump 42 (or 44) also communicates with the leveling jacks. From the aspect of merely leveling the vehicle these could be single acting operating against the weight of the vehicle. This, however, would require some means for returning their lower ends to road clearing position when the vehicle is moved over terrain. They are therefore preferably of the double acting type so that they may be raised to road clearing position. The mast raising and lowering cylinders also communicate with pump 42 (or 44) and are of the double acting type to thus pro vide a rigid but extensible link between the mast and the vehicle. Since double acting hydraulic actuators and the valves for controlling same are well known in the art, details of these elements have been omitted in the interests of simplification of the disclosure.
In the operation of the apparatus it will be assumed that the vehicle has been moved to the drilling site with the mast disposed in lowered position. It may also be assumed that the drill pipe magazine is filled and a length of drill pipe is afifixed to the drilling head and supported at its other end by support tong 106. The mast is then raised to a desired angular position, such as vertical, and leveling jacks 56, 58 are operated to place the axis of the drill rod in alignment with the hole to be drilled. The drilling head 74 with its attached first pipe is then lowered by motor 94 and the lower end of the pipe is passed through dog assembly 120. A suitable drill bit, which will normally have a diameter in excess of the pipe, is then attached to the lower end of the pipe and the dog assembly is then released. The pipe is then rotated and translated by power until the first pipe has drilled a hole to a depth at which its upper end is adjacent dog assembly 120. Power is then discontinued and the pipe is clamped to assembly 120. The drilling connection between the upper end of the pipe and the driving head is then broken and the drilling head reversed to complete the separation. The drilling head is then returned to its upper position and the mast lowered to its horizontal position above the magazine. Prior to lowering of the mast to its horizontal position, the pipes in the magazine have been automatically raised one pipe diameter so that the uppermost pipe will be in alignment with drilling head 74 and is also in proper position to be grasped by support tong 106. The drilling head is then actuated toward the uppermost pipe and connected to same by power rotation thereof. The mast is then returned to its former elevated position after which the tong 106 is released and the lower end of the pipe is connected to the upper end of the first pipe. The clamping dog assembly 120 is then released and the hole deepened by power in the same manner previously described. The same operations continue until desired drill depth is reached after which the pipes are returned to the magazine, as previously described. During all of the drilling operation air under pressure is delivered through the pipe string which forceably removes drillings upwardly around same. As will be apparent, the manner of sequentially coupling the pipe sections together during drilling and the uncoupling of same during removal of the string from the drilled hole is conventional, the principal difference residing in the manner in which the pipes are removed from and returned to the magazine.
As so far described, the mast 62 must be raised to a vertical position so that a pipe may be aligned with the aperture in clamping dog assembly 120. On some occasions it is desired to drill a hole at an angle from the vertical which necessitates tilting the mast from the vertical, such as rearwardly therefrom. Since mast pivot 78 is disposed rearwardly from dog assembly 120, a rearward tilt of the mast would require moving assembly forwardly and also rotating it about an axis transverse to the vehicle so that the aperture is concentric with the drill pipe axis. FIG. 7 illustrates such construction in which the dog assembly 120 and its hydraulic actuators 122, 124 are secured to a table 156, or the like, which is mounted on the vehicle frame 12 in such manner that it may be bodily adjusted in a direction longitudinally of the vehicle and also angularly adjusted about a transverse axis as indicated by arrows. As will be apparent when the mast axis is tilted rearwardly from vertical, as indicated by the dotted position, table 156 may be moved forwardly and also rotated to place the aperture concentric with the axis of tilt.
What is claimed is:
1. In a steerable vehicle of the type having an engine for propelling same and for supplying power to instrumentalities carried thereby and having an elongated mast pivotally carried by the vehicle for positioning same in a generally vertical position or a generally horizontal position at the top of the vehicle, the improvements, comprising:
a. a pipe drilling head reciprocably carried by the mast for axial movement therealong and power means for moving same in opposite directions, the drilling head adapted to be detachably connected to one end of a series of pipes; a supply of stationary drill pipes carried by the vehicle in vertically stacked relation along generally horizontal axes adapted to be serially connected or disconnected to the drilling head when the mast is dispomd in its horizontal position;
c. means for elevating and lowering the supply in increments corresponding to the diameters of the drill pipes, whereby the axis of the uppermost pipe may be disposed in alignment with the drilling head and may be connected or disconnected therewith;
d. means carried by the mast for grasping the uppennost pipe of the supply for maintaining it in axial alignment with the drilling head and for maintaining such alignment while the mast is moved from its horizontal position to its vertical position, and thereafter adapted to be released from the pipe.
2. Apparatus in accordance with claim 1 wherein said mast, when in vertical position, is disposed centrally at the front end of the vehicle, and a control station adjacent the mast from which a drilling operation may be observed, the maneuverability of the vehicle also being controlled from said station, whereby a single operator may maneuver the apparatus to a drilling site and also control the drilling thereat.
3. Apparatus in accordance with claim 2 including an internal combustion engine for propelling the vehicle including a power transfer box containing clutch means for selectively driving traction wheels of the vehicle or driving accessories, such as an air compressor and hydraulic pumps.
4. Apparatus in accordance with claim 3 wherein all wheels of the vehicle are driven through the transfer box.
5. Apparatus in accordance with claim 3 wherein all wheels are steerable.
6. Apparatus in accordance with claim 1 wherein the means for elevating and lowering said supply comprises hydraulic rams, said drilling head and means for moving same being driven by hydraulic motors, and hydraulic pump means for operating same.
7. Apparatus in accordance with claim 6 including means for adjusting the incremental length of movement of the hydraulic rams.
8. Apparatus in accordance with claim 1 including a guide secured to the vehicle for longitudinal adjustment relative thereto and for pivotal adjustment about a transverse axis whereby it may be fixed in alignment with the lower end of a drill pipe when the mast is tilted from but adjacent the vertical.
stacked relation adapted to be serially connected or disconnected to the drilling head when the mast is disposed in its first position;
0. means for elevating and lowering the supply in increments corresponding to the diameters of the drill pipes, whereby the axis of the uppermost pipe may be disposed in alignment with the drilling head and may be connected or disconnected therewith;
d. means carried by the mast for grasping the uppermost pipe of the supply for maintaining it in axial alignment with the drilling head and for maintaining such alignment while the mast is moved from its first position to its second position, and thereafter adapted to be released from the pipe.
10. In a device of the type having means for supplying power to instrumentalities carried thereby and having an elongated mast pivotally carried thereby for positioning same in a generally vertical position or a generally horizontal position, the improvements, comprising:
a. a pipe drilling head reciprocably carried by the mast for axial movement therealong and power means for moving same in opposite directions, the drilling head adapted to be detachably connected to one end of a series of pipes;
b. a supply of stationary drill pipes carried by the device in stacked relation adapted to be serially connected or disconnected to the drilling head when the mast is disposed in its horizontal position;
c. means for elevating and lowering the supply in increments whereby the axis of the uppermost pipe may be disposed in alignment with the drilling head and may be connected or disconnected therewith;
d. means carried by the mast for grasping the uppermost pipe of the supply for maintaining it in axial alignment with the drilling head and for maintaining such alignment while the mast is moved from its horizontal position to its vertical position, and thereafter to be released from the pipe.
l l l t
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|U.S. Classification||175/52, 173/164, 175/85, 173/28|
|International Classification||E21B19/00, E21B19/14, E21B7/02, E21B15/00, E21B15/04|
|Cooperative Classification||E21B19/14, E21B7/022, E21B15/04, E21B7/027|
|European Classification||E21B7/02C, E21B7/02S, E21B19/14, E21B15/04|