US3431989A - Planetary excavator - Google Patents

Description

PLANETARY EXCAVATOR Filed July 31, 1967 March 11, 1969 w. D. WATERMAN 3,431,989

PLANETARY EXCAVATOR Filed July 31, 1967 Sheet 3 of 9 INVENTOR Q6 M4 4 /s' D. Mnne/z/mu ATTORNEYS March 11, 1969 w. D. WATERMAN 3,431,989

PLANETARY EXCAVATOR Filed July 31, 1967 Sheet 4 of 9 I INVENTOR WM 1. /6' Z; MTE'EMAA/ TQ NEY' March 1969 w. D. WATERMAN 3,431,989

PLANETARY EXCAVATOR Filed July 31, 1967 mvmozz l V/u/s .2 MTEQMAN March 11, 1969 wQo. WATERMAN PLANETARY EXCAVATOR Sheet Filed July 31, 1967 INVENTOR 1444; l5 .0. M/ATE'RMAIV T NEY? March 11, 1969 w. D. WATERMAN 3,431,989

'PLANETARY EXCAVATOR f-iled July 51, 1967 Sheet 7 of 9 III I T NEYS INVENTOR March 11, 1969 w, WATERMAN 3,431,989

PLANETARY EXCAVATOR Filed July 31, 1967 INVENTOR Wad/5 0. WATEEMAA/ A mfw:

United States Patent 3,431,989 PLANETARY EXCAVATOR Willis D. Waterman, 626 Max, Salina, Kans. 67401; Betty J 0 Waterman, administratrix of said Willis D. Waterman, deceased Continuation-impart of application Ser. No. 420,704, Dec. 23, 1964. This application July 31, 1967, Ser. No. 657,359 U.S. Cl. 175-95 4 Claims Int. Cl. E21b 3/02, 9/24; F16h 55/34 ABSTRACT OF THE DISCLOSURE A rotary excavator.for drilling large diameter shafts into the earth and in which a pilot hole cutter and laterally extended hole cutters are reversely driven by resilient drive members powered by reversible motors, and the laterally extended cutters move the cuttings into the pilot hole, for removal of the cuttings from the pilot hole through a central pipe as a result of the high velocity flow of drilling fluid through the pipe to the surface of the earth.

This is a continuation-in-part of my copending application Ser. No. 420,704, filed Dec. 23, 1964, for Planetary Excavator, and now abandoned.

Summary of the invention A stationary pipe extending into the shaft in the earth supports oppositely rotating cutter assemblies which are driven by motors in the shaft and carried on the pipe. Each motor individually drives an intermediate member which in turn drives both cutter assemblies in opposite directions. The pipe carries cuttings from the shaft.

Description This invention relates to earth boring or drilling machines, more particularly to a device for the sinking of large-diameter sh-afts from the surface either vertically or in a more-or-less horizontal direction.

The excavation of chambers or passageways of from ten to twenty-five feet by a single machine without the use of explosives and/or extensive hand labor has long been desired by the mining and construction industries in reducing the costs of shafts, piers, and footings. This invention for the first time makes available a rugged and practicable machine capable of driving openings of this size rapidly, efiiciently and economically.

It is an object of this invention to provide an excavator which can be attached to and operated from a conventional crane or which can operate below the usual drilling platform on the conventional drilling rig.

It is another object of this invention to provide a largediameter drilling means which is capable of slow-to-rapid rotation and controlled changes of direction clockwise and counterclockwise.

A further object of this invention is a large-diameter drilling machine which is readily and simply adjusted for a substantial range of hole sizes.

Still another object of the invention is to provide a rugged and durable assembly for driving the cutting elements of a large diameter drilling machine in an environment of drilling fluid which is employed to carry the cuttings from the hole, the driving assembly including resilient drive and driven members coengaged with one another and confined in frictional coengagement by a surrounding ring. The drive assembly being supported in the hole by a motor mount having motors which drive certain of the resilient drive elements, the motor mount being held against reactive rotation by a pipe or conduit leading to the bottom of the hole and through which drilling fluid is caused to flow for the purpose of carrying cuttings ice upwardly through the pipe. In the use of the apparatus in the environment of the drilling fluid, which is inherently abrasive, an advantage results in respect of the increased friction drive capacity of the resilient drive members caused by the abrasive particles in the drilling fluid; whereas, in the case of the usual gear drives the presence of abrasive particles is detrimental.

Another object of the invention is to provide a drive mechanism in a large diameter drilling machine wherein resilient drive and driven members are employed for effecting rotation of the cutting elements, such resilient drive-and driven members being capable of absorbing heavy shock loads so as to prevent damage to the drilling apparatus, and being capable of compensating for unequal torque loads which are inherent in the operation of large diameter drilling machines, notwithstanding efforts made in accordance with the invention for equalizing torque loads. 'In the latter instance, it is a further object of the invention to provide resilient drive and driven members which are substantially arranged as planetary drive elements including a sun member which is relatively large and which is adapted to drive a centrally located portion of the cutting elements in one direction, while correspondingly large planet members coengaged with the sun member and within a ring member are adapted to drive an outer portion of the cutter elements, in the other direction, so that the work load resulting from operation of the drilling apparatus is substantially equally distributed or balanced.

Still another object of the invention is to provide a large diameter drilling machine, the cutting elements of which include a pilot cutter for cutting a pilot hole in advance of the main hole, the other cutters, adapted to drill the main hole, being arranged to move cuttings into the pilot hole as drilling progresses, and a conduit being provided and leading from the pilot hole to the surface of the earth so that drilling fluid filling the hole may be pumped from the conduit from the pilot hole so as to efiiciently remove cuttings as the drilling progresses.

These and other objects vw'll be readily apparent from the following description and appended drawings in which:

FIGURE 1 shows this large-diameter drill mounted on a crane;

FIGURE 2 is an enlarged view of the torque-arm assembly along the line 2-2 of FIGURE 1;

FIGURE 3 is an enlarged vertical view, partly in section, of the planetary driving mechanism and cutter assembly;

FIGURE 4 is a horizontal view, partly in section of the drive assembly, taken along the line 4-4 of FIGURE 3;

FIGURE 5 is a horizontal view, partly in section, of the cutter support, taken along the line 5-5 of FIG- URE 3;

FIGURE 6 is a horizontal view, partly in section, of the cutter assembly, taken along the line 66 of FIG- URE 3;

FIGURE 7 is an alternate form of cutter for use in harder formations;

FIGURE 8 is an enlarged vertical sectional view of the sun wheel and associated structure;

FIGURE 9 is a horizontal view of the upper roller and guide assembly taken along the line 9-9 of FIGURE 8;

FIGURE 10 is a view partly in vertical section and partly in elevation illustrating a modified cutter assembly;

FIGURE 11 is a view in transverse section on a reduced scale, as taken on the line 1111 of FIGURE 10;

FIGURE 12 is a view in transverse section on a reduced scale, as taken on the line 12-12 of FIGURE 10.

Referring more particularly to FIGURE 1, there is shown more-or-less diagrammatically a crane 200, having a boom with associated guy and control cables, designated by the numeral 12. The crane is provided with suitable transport and support means 13 for moving it to the drilling site and holding it in position during the drilling operation. A cable 14 paid out from a drum, not shown, in the control cabin of the crane and passing over the sheaves 15 at the upper end of boom 12 is provided with a hook 16. Depending from hook 16 is a cable spacer 11 and a plurality of cables 17 which are attached to the lifting ring 18 on the upper part of the driving and cutting assembly 300, as shown in more detail in FIGURE 3. Separately controlled cable 70 passing over sheave 69 provides for adding to or removing sections of pipe from the drill string in the usual manner.

Rigidly attached to crane 200, and extending outwardly thereof is a torque-arm assembly 20. As shown in FIG. 2 assembly 20 may be a framework formed of two members 21, each suitably attached to the crane at the inner ends and provided with an enlarged sleeve 22 transversely thereof at the outer end. Between the sleeves 22, there is a kelly 23 adapted to be disposed within a holding bushing 23a, and also adapted to be connected to a length of pipe 28. On either side of the kelly bushing 23a, there is attached a pipe 24 each of which is rotatably fitted at its outer side, within one of the sleeves 22. A third pipe 25 extends outwardly from the kelly, and is provided at its end with two braces 26, which are rigidly attached to pipes 24 near sleeves 22 substantially as shown. This subassembly including the kelly bushing is thus a rigid unit which is pivotally mounted in sleeves 22 so that it is capable of limited movement in relation to pipes 21. These latter may be further supported by cables 27 suitably attached to boom 12. The kelly 23 and associated assembly serve to hold the pipe 28 securely against rotative movement due to the rotative forces applied thereto by the planetary drive assembly, as described hereinafter, while allowing sliding axial movement of the kelly 23 and attached pipe 28 during drilling operations. Although members 21, 24, 25 and 26 are shown as pipes, which are preferred for most installations they may be rods or other structural shapes with the desired strength and rigidity.

Referring now to FIGURE 3, at its lower end the pipe 28 is attached to the drive and cutting assembly 300 by conventional fittings designated generally by the numeral 29, and adapted to accommodate fluid flow. Beneath the lifting ring 18 and integral therewith are a plurality of motor mount beams 30, arranged in pairs, each pair supporting a motor 31.

In the preferred form of large bore excavator, motors 31 are reversible hydraulic motors being supplied with hydraulic fluid under pressure through hoses 58 from a compressor system 59 in the conventional manner. Provision, of course, is made for extending hoses 58 as required with the increasing depth of hole.

A shaft 32 extends downwardly from each motor 31 and carries at its lower end a wheel 33. Preferably, each wheel 33 is the dual rim type with a pair of resilient tires 34 mounted thereon. Tires 34 are of rubber or other elastomer suitable for maintaining friction drive. It is preferred that these tires be pneumatic, such as are used on heavy-duty trucks, but solid or semisolid tires may be used in some installations. Pneumatic tires may be filled with liquid instead of air or other gas if desired.

As shown in FIGURES 3 and 4, there are six such motor and wheel assemblies, equally spaced about the drill pipe. Surrounding these motor and wheel assemblies is a circular ring or drive shell 35, extending upwardly from a horizontal ring plate 36. Ring plate 36 may be made of a plurality of arcuate sections for ease of fabrication and assembly. Shell 35 may also be in sections for ease of assembly and also to facilitate servicing of the several wheels 33. To reduce the weight and also to facilitate the fabrication, drive shell 35 preferably consists of an inner shell 35a and an outer shell 35b with a plurality of rods or pipes 65 extending vertically between them. Extending radially inwardly from ring plate 36 are a plurality of pipes 37 which are attached at their inner ends to a lower sleeve 38, which extends about the lower end of pipe 28 for rotation thereabout, as will be hereinafter described. The spaces between the several pipes 37 may be covered by a plurality of sector-shaped deck plates 39. Supporting flanges 40 for deck plates 39 are welded or otherwise affixed to radial pipes 37.

As shown in FIGURES 3, 5 and 6, pipes 37 form the upper elements of the cutter support assembly, other elements of which, designated as 37A, extend downwardly from horizontal pipes 37, are provided with fittings 41 for attachment of the cutter assemblies 350A, 350B. The diameter of the excavation is largely controlled by the over-all length of cutter assemblies 350A, 350B. In the preferred embodiment the excavator is capable of driving excavations having a diameter varying from about 10 /2 feet to about 25 feet.

The supporting framework formed of the pipes 37 and 37A, may be further braced by the rods 66, which may be adjusted by turnbuckles, not shown, or other conventional means.

Means are provided for supporting the abovementioned sleeve 38 for rotation about the pipe 28, such supporting means in the illustrative embodiment essentially hanging the sleeve 38, and thus ring 35, from the motor mounting means or beams 30, the ring 35 thereby also being revolvable about the pipe 28.

Referring more particularly to FIGURE 8, the lower sleeve 38, to which are attached radial arms 37, is provided at its lower end with an outwardly extending flange 42. Roller members 43 on the lower roller guide assembly 44 at the lower section of a cylindrical member 45 provide support for sleeve 38 and permit rotation thereof with a minimum of friction. As shown in enlarged detail in FIGURE 8, tubular member 45 may be of sectional construction and may be flanged at its upper end 46 rotatably supported by roller members 48 of roller guide assemblies 47. These assemblies 47 are mounted on, as by welding or the like, and depend from the lower side of motor mount beams 30.

Thus, the tubular member 45 is rotatable relative to the pipe 28, and ring 35 is rotatable relative to tubular member 45. A pair of inner wheels 49 are attached to the tubular member 45 and rotate therewith. On the rim of each wheel 49 is a resilient tire 50 of rubber or other suitable elastomeric material which is in frictional engagement with one of the tires 34 on the wheels 33. Tire 50, like tires 34, may be filled with gas or liquid or may be solid or semi-solid, to suit the intended service.

As shown in FIGURE 8, pipe 28 and tubular member 45 may be in flanged sections of convenient lengths which are coupled at the flanges my heavy-duty bolts 51. However, other types of couplings used in oil field work, such as quick-connecting clamps, may be substituted where applicable.

At the lower end of the tubular member 45 is mounted a pilot drill 52. FIGURE 1 shows, more or less diagrammatically a conventional tricone bit for this purpose; however a drag bit or other bit of appropriate size and design may also be employed. As is customary the bit 52 will have a shank connectable to member 45 and capable of permitting the flow of drilling fluid and cuttings into the member 45. At the upper end of drill pipe 28, there is provided a coupling 53 for drilling fluid hose 54. This hose, in turn, is connected to the suction side of pump 55 which discharges into mud pit 56. Settled drilling fluid is returned to the borehole through overflow pipe 57. Thus, as drilling progresses and responsive to operation of pump 55. there will be a high velocity flow of drilling fluid through bit 52 into tubular member.45 and thence upwardly through pipe 28, so that cuttings will be efficiently removed from the pilot hole.

In addition to the pilot drill 52 and radially extending cutter assemblies 350A, 350B, reamer cutters may be provided on the lower edge of shell 35. These are spring-loaded so as to operatively engage the periphery of the hole upon reverse rotation of the drill assembly that is counter to drilling direction.

More particularly, the cutter assemblies 350A and 350B as thus far described, may comprise, as best seen in FIGURES 3 and 6, a series of cutter discs 61 disposed for rotation on shafts mounted on the supporting structures as by the fittings 41 previously referred to, with the shaft axis arranged in skewed relation to lines extended radially of the hole. By virtue of this arrangement of the cutter assemblies, each of the cutter discs 61 is caused to drag across the bottom of the hole as the drilling progresses, whereby cuttings loosened by the earth will be moved progressively toward and into the pilot hole formed by the pilot bit 52. Such progressive moving of the cuttings into the pilot hole assures that the drilling fluid being pumped upwardly through the pipe 28 from the pilot hole can efliciently entrain the cuttings therein and carry the cuttings to the top of the hole and into the pit 56. The cuttings will settle out of the drilling fluid in the pit 56 and the drilling fluid will return to the hole through the overflow 57 leading from adjacent the top of pit 56 into the hole.

Referring to FIGURE 7, there is generally illustrated a modified form of cutter assemblies adapted to be supported in the manner of the disc assemblies 350A and 350B. These modified cutters designated 71 may be employed for drilling through hard earth. These cutters 71 comprise cylindrical bodies capable of withstanding the forces involved when they are caused to revolve in contact with the earth. Spaced longitudinally of the cylinders are cutting edges which are composed of material such as tungsten carbide formed as rings about the cylinder. Such a construction, since the different cutting edges traverse different distances as the cutting assemblies are rotated, causes a cutting action similar to that of a rasp.

Operation It will now be understood that in the operation of the drilling apparatus as thus far described, it will be lowered into engagement with the earth by the crane 200 or such other suitable support as may be employed at the earths surface, and the hole as it progresses will be maintained full of drilling fluid or mud inthje usual manner. As the motors 31 are operated by the pumping of power fluid thereto from ,the pump 59,' each of the motors 31 will drive oneof the driving wheels 33, the tires of which are in engagement with the ring 35 which extends circumferentially in engagement with all of the wheels 33, so that as shown in FIGURE 4, as the wheels 33 are driven in a counter clockwise direction, counterclockwise rotation will be imparted to the ring 35 at a speed dependent upon the diameter of the wheels 33 and the speed at which they are driven. The motors 31 and the wheels 33 are held against unitized revolution about the axis of the hole by virtue of the fact that the motor mounts 30 are connected through the pipe 28 to the kelly 23 which is fixed against rotation by the torque arm 20.

Each of the wheels 33 is further engaged with the central wheels 49 fixed on the tubular member 45 which, as previously indicated, is adapted to revolve relative to the pipe 28 as well as relative to the ring 35. Accordingly, the drive means may be characterized as planetary in nature, the wheels 49 being the sun member of the planetary system and the wheels 33 being the planetary members of the planetary system, which are adapted to drive the ring member 35.

Inasmuch as substantial loads are irnposed upon the drilling apparatus it is desirable that the work load be equalized by causing as nearly as possible and practicable equal linear travel of the respective cutters. In part, this is accomplished in the present invention by employing cutting discs in the embodiment of FIGURE 1 which are progressively smaller from the outer disc toward the inner disc, forming a conical rotary disc cutter assembly, each disc of which will travel the same distance as it traverses the bottom of the hole. In addition, however, the work load is substantially equally distributed by causing rotation of the wheel 49 at a substantial rate, thus causing the pilot bit 52 to rotate at a rate greater than the rate of rotation of the cutter assemblies 350A and 350B. It will be understood in this connection that this relative rate of rotation is accomplished by reason of the fact that planet members 33 are large in diameter and therefore, cause substantial rotational speed of sun member or wheel 49.

Moreover, the tires 34 and 50 of the driving and driven wheels are confined within the ring 35 in pressure loaded engagement with one another so as to assist in the frictional drive therebetween, and the presence of abrasive particles, which would be objectionable in a gear drive, enhance the frictional drive between the resilient tires.

The sun member or wheel 49 will be caused to rotate in a clockwise direction or opposite to the ring 35 so that the cutter assemblies 350A and 350B will revolve about the hole axis in a counter clockwise direction, while the pilot bit 52 revolves in a clockwise direction, thus tending to balance the torque and to reduce the holding effect required of the torque arm. 20.

As the hole progresses the cutters 350A and 350B, as previously indicated, will cause movement of the cuttings into the pilot hole, the location at which the drilling fluid filling the hole passes into the conduit leading to the pump 55. Thus, the velocity of the drilling fluid passing into the pilot hole and into the conduit 28 will insure entrainmeht of the cuttings in the fluid stream so that they will be efliciently removed from the hole.

Referring now to FIGURES 10 through 12, there is illustrated a modification of the invention in which the power mechanism including the outer ring 35, central driven wheels 49 and intermediate drive wheels 33, is the same as that previously described. In this modified construction, however, the cutting elements are somewhat differently arranged, and more particularly, a number of cutter discs which form the bottom of the hole are caused to revolve with and in the direction of the pilot bit 52, while other of such cutting discs revolve in the opposite direction.

As shown in FIGURE 10, the tubular member 45 is provided with a downward extension connected to the pilot bit 52. Carried by the extension 145, suitable outwardly extended support arms 137a which are provided with fittings 141 on which are journaled the shafts of cutter assemblies 1350a, each cutter assembly comprising a number of cutter discs 161, and as seen in FIGURE 12, there being a number of such assemblies spaced about the tubular extension 145 and disposed with their axis skewed relative to lines extended radially of the member 145. Braces 166 extended between the support members 137a, as in the previously described embodiment, are adapted to rigidly interconnect the cutter assemblies. These cutter assemblies 1350a will, asseen in FIGURE 10, cut an intermediate section from the bottom of the hole above the pilot hole formed by the pilot bit 52, and inasmuch as the cutter assemblies are skewed as previously indicated, cuttings formed thereby will be caused, as shown by the arrows, to be moved into the pilot hole for purposes of removal by the drilling fluid.

In addition to the cutter assemblies 1350a, the cutting means includes additional cutter assemblies 1350b which are supported on support arms 237a mounted beneath the support members 37a on which the driven ring 35 is mounted, whereby rotation of the ring 35 will impart rotation to the cutter assemblies 1350b. Like the cutter assemblies 1350a, the cutter assemblies 1350b include cutter discs 161 disposed upon a shaft which is mounted with its axis skewed relative to lines extending radially of the drilling assembly. Thus, the cuttings formed by the cutters 1350b will be caused to move inwardly into the intermediate hole section formed by the cutters 1350a and with the cuttings formed by the latter cutters will be caused to move into the pilot hole 52 for removal of the cuttings by the circulation of drilling fluid. In view of the foregoing, operation of the modified construction of FIG- URES 10-12 will be understood without further elaboration.

While preferred embodiments of the excavation and its mode of operation have been described, it will be obvious to persons skilled in the art that changes or alterations might be made without departing from the invention in its broader aspects and, therefore, it is the aim of the appended claims to cover all such changes and modifications as fall within the true scope and spirit of this invention.

I claim:

1. In a rotary excavator for sinking a substantially vertical shaft in the earth, the shaft containing a drilling fluid to support the walls thereof, the combination of: a central non-rotary pipe extending downward into the shaft, a laterally extending support fixed to the pipe below the level of the drilling fluid in the shaft, a central elastomeric driven tire mounted to turn about the axis of said pipe, a pilot bit, a tubular member connecting said pilot bit to said tire to be driven therefrom to form a pilot hole in the bottom of the shaft, a drivering having an internal cylindrical surface, means mounting the drive ring on said tubular member to turn about the axis of said pipe, a cutter assembly connected to the drive ring for cutting the remainder of the bottom of the shaft, a plurality of elastomeric driving tires rotatably mounted on said support and each frictionally contacting both said central driven tire and said internal cylindrical surface of said drive ring, said driving tires serving to center said drive ring with respect to said central driven tire, a plurality of motors fixed on said support, one motor for turning each of said driving tires, respectively, whereby said pilot bit and said cutter assembly may be turned in opposite directions, and means for causing an upward flow of drilling fluid through said tubular member and said pipe to remove cuttings from the shaft.

2. In a rotary excavator for sinking a substantially vertical shaft in the earth, the shaft containing a drilling fluid to support the walls thereof, the combination of: a central non-rotary pipe extending downward into the shaft, a laterally extending support fixed to the pipe below the level of the drilling fluid in the shaft, a central driven element mounted to turn about the axis of said pipe, a pilot bit, a tubular member connecting said pilot bit to be driven from said element to form a pilot hole in the bottom of the shaft, a drive ring element encircling said central driven element, means mounting said ring element to turn about the axis of said pipe, a cutter assembly driven by said ring element for cutting the remainder of the bottom of the shaft, said cutter assembly including a plurality of rotary cutters each having its axis of rotation skewed in relation to a radius line of the pipe whereby cuttings loosened from the earth are moved progressively towards and into the pilot hole, a plurality of interme- .diate driving elements mounted on said support and each driving both said central driven element and said driven ring elements, a plurality of motors mounted on said support, one motor for turning each of said intermediate driving elements respectively, whereby said pilot bit and said cutter assembly may be turned in opposite directions, and means for causing an upward flow of drilling fluid through said tubular member and said pipe to remove cuttings from the pilot hole.

3. In a rotary excavator for sinking a shaft in the earth, the shaft containing a drilling fluid to support the walls thereof, the combination of: a central nonrotary pipe extending into the shaft, cutter means revolvable in said shaft, and power means supported on said pipe beneath the level of drilling fluid in said shaft for driving said cutter means, said cutter means including first cutter means revolvably disposed about said pipe, second cutter means revolvably disposed about said pipe and within said first cutter means, said power means including a drive ring connected to said first cutter means, a central drive member connected to said second cutter means, intermediate drive members frictionally engaged with said drive ring and with said central drive member, said power means also including individual motors each connected to and driving one of the respective intermediate drive members, means for holding said intermediate drive members against revolution about said central drive member, and means for causing the flow of said drilling fluid upward through said pipe to remove cuttings from the shaft.

4. A rotary excavator as defined in claim 3, wherein the individual motors are reversible, and wherein said cutter means includes reaming cutters having means for urging the same into engagement with the side wall of said shaft upon rotation of said motors in one direction.

References Cited UNITED STATES PATENTS 902,517 10/1908 Wittich --104 X 1,747,908 2/1930 Seifert 175-391 X 1,826,396 10/1931 Gault 175319 2,105,091 1/1938 MacKay 17595 2,111,422 3/1938 Fawick 74216 X 2,384,397 9/1945 Ramsay 175-319 X 2,766,978 10/ 1956 Robbins 175-319 X 3,024,852 3/1962 Jewell 175319 X 3,185,226 5/1965 Robbins 175-102 FOREIGN PATENTS 782,851 3/1935 France.

87,952 8/1896 Germany.

892,581 10/ 1953 Germany.

CHARLES E. OCONNELL, Primary Examiner,

IAN A. CALVERT, Assistant Examiner.

US. 01. X.R.

Images