US2979142A - Apparatus for drilling wells - Google Patents

Description

April 1 1, 1961 J. A. REID APPARATUS FOR DRILLING wELLs 4 sheets-sheet 1 Original Filed Sept. 20, 1954 illilllllllf'.

4 Sheets-Sheet 2 J. A. REID APPARATUS FOR DRILLING WELLS April l1, 1961 Original Filed Sept. 20, 1954 Aprll 11, 1961 J. A. REID APPARATUS FOR DRILLING WELLS Original Filed Sept. 20, 1954 4 Sheets-Shet 5 April 11, 1961 1 A RE|D 2,979,142

APPARATUS FoR DRILLING WELLS original Filed sept. 2o, 1954 4 Sheets-Sheet 4 INEN TOR. By dem www W APPARATUS non DRiLLlNG WELLS James A. Reid, Bartlesville, Okla., assignor to Phillips Petroleum Company, a corporation of Delaware Y Original application Sept. 20, 1954, Ser. No. 456,911, now Patent No. 2,825,534, dated Mar. 4, 1958. Divided and this application July 3, 1957, Ser. No. 669,763

4 Claims. (Cl. 175--105) This invention relates to apparatus for drilling wells. In another aspect, it relates to a drill bit of improved construction.

This application is a division of Serial No. 456,911, tiled September 20, 1954, now U.S. Patent No. 2,825,534.

Heretofore, oil or gas wells have ordinarily been drilled in the earth by a rotary drill or by cable tools. ln both of these drilling systems, a string of drill pipe has been used which extends from the drilling tool to the surface of the earth. In the case of rotary drills, this drill string transfers torque from a prime mover at the surface of the earth to the drilling tool at the bottom of the well. In drilling with cable tools, the drill string carries drilling mud to the bottom of the well, and devices have been proposed, depending upon friction between the drilling tool and drill string, to cause rotation of the bit as the drilling progresses. Such rotation of the bit is quite important to obtain a proper drilling action.

It will be evident that the use of such a string of drill pipe greatly increases the cost of the drilling operation. First, the cost of the pipe is a factor and, second, it is dicult and costly to remove a long string of pipe to repair or replace the bit. Where a drill-rotating device is attached to the drill string, it s necessary to provide a device for preventing reverse rotation of the drill string relative to the drill hole.

In accordance with this invention, l obtain rotation of the bit without utilizing a drill string by securing a rotator device to the drilling tool, for example, to the drill stem or drill bit. This device engages the formations defining the drill hole in such fashion as to cause a unidirectional rotation of the drilling tool. In this manner, part of the reciprocatory or vibrational energy applied to the drill bit is used to effect rotation thereof.

This permits a downhole prime mover to be used, which can advantageously be of the electromagnetic or magnetostrictive type, so that the drill string can be eliminated and the complete drilling apparatus suspended by a cable or conduit for carrying drilling fluid to the drilling area. Thus, the drilling tool can be removed merely by reeling in the cable or conduit without removing and disassembling a long strip of drill pipe. Although the most advantageous applications of the present invention are to systems utilizing a downhole magnetostrctive or electromagnetic prime mover, it will be evident that, in some cases, the motive power can be supplied from the surface of the earth and transmitted through a cable to the drilling tool.

Accordingly, it is an object of the invention to provide well drilling apparatus or" improved construction.

. It is a further object to provide apparatus for obtaining rotation of the drill bit without the use of a drill string.

Itis a still further object to provide a system where the prime mover can be located downhole with the drilling tool and suspended by a cable or flexible conduit.

Various other objects, advantages and features of the invention will become apparent from the following de- I 2,979,142 Patented Apr. ll, 'i961 tailed description taken in conjunction with the accompanying drawings, in which:

Figure 1 is a vertical elevational view, partially in section, of a drilling tool constructed in accordance with the invention;

Figure 2. is a vertical sectional view, partially in elevation, of a swivel unit;

Figure 3 is a perspective view of a drill bit constructed in accordance with the invention;

Figure 4 is a sectional View taken along the line 4 4 of Figure 3, looking in the direction of the arrows;

Figure 5 is a vertical elevational view of a modied form of drilling tool;

Figure 6 is a vertical sectional View, partially in elevation, of an electromagnetic prime mover;

Figure 7 is an enlarged vertical sectional view partially in elevation, of a bit rotator device; and

Figure 8 is a sectional view taken along the lines 3--8 of Figure 7, looking in the direction of the arrows.

Referring now to Figures 1 to 4, inclusive, I have shown an elongated drilling tool 10 comprising a cylindrical drill stem 11 and a bit 12. Mounted within the drill stem 111 and protruding upwardly therefrom is a niagnetostrictive driving unit or motor 13 which is secured by a swivel connection 14 to a ilexible conduit or cable 15.

When actuated in the manner hereinafter explained, the prime mover produces a vibratory movement of the drill bit.

Referring to Figures 3 and 4, it will be noted that the drill bit has a series of teeth 12T and openings 16, the teeth being defined by a series of at surfaces 17 which are inclined at a small angle with respect to a plane perpendicular to the axis of the tool. Certain of the surfaces 17 have a recess 13, and a spring element 19, preferably formed from steel, has one end 19a thereof secured within each recess 18, as by a bolt 20, and its other end 19b protruding beyond the face of the associated ilat surfaces i7.

As the bit descends and contacts the formation at the bottom of the well in its drilling action, it will be evident that the strips or elements 19 are pushed inwardly toward the face of the drill bit and thereupon exert a force upon the drill bit tending to rotate it in a counterclockwise direction, as viewed in Figure 3. These elements, of course, exert no force tending to rotate the drill bit in the opposite direction and, hence, can be referred to as devices secured to the drill bit and engageable with the vadjoining formation to cause rotation of the drill bit in one direction but not in the other direction.

As shown and preferably, the motor which provides the aforementioned vibratory drilling action is located at the bottom of the hole and forms a part of the drilling tool. In the embodiment shown, this prime mover includes an annular coil 22 mounted concentrically within the, drill stem 11. Mounted within the coil is an annular core formed from a series of vertical strips or laminations 23 of magnetostrictive material which are attached, atthe lower end thereof, to the drill bit 12 by a pair of heavy metal plates 23a, 23b and, at the upper end thereof,` to a pair of heavy metal plates 24 and 25. An annular sealing device 26 is disposed at the top of the laminated core defined by the strips 23 of magnetostrictive material. These strips are arranged to define a 'central passage .2y-7 communicating with the openings 16, Figure 3, in Ythe drill bit for the purpose of supplying drilling fluid thereto. When the coil 22, Figure 1, is energized' by alternating current of proper frequency, the magnetostrictive elements vibrate and impart a vibratory movement to the drill bit 12 in the form of rapid and repetitive power impulses.

'Ihe swivel 14 includes an adapter 30 bolted to the plates 24, 25 and secured to a housing 31 by mechanism including roller bearings 32, 33 and a rotary seal 3-4. This structure permits the drilling tool to rotate freely relative to the housing 3 1 which is suitably connened to the cable or hose 15, Figure l. The entire unit is of suliicient weight to permit proper operation of the drill bit.

Current is supplied to the coil 22 by two leads 35 and 36 which extend through sets 37' and 33 of slip rings and additional conductors, one of which is indicated at 39, to the surface.

In operation, a drilling fluid is supplied to the bit through the hose 15, Figure l, a passage 40 extending through housing 3l, and the passage 27 to the openings 16 in the drill bit.- At the same time, current is supplied to the coil 22 through leads 35 and 3d at the frequency of resonance of the mechanical system consisting of the magnetostrictive elements 23, the drill stem, the drill bit and the parts Secured thereto. This produces a vibratory drilling movement of the drill bit 12. Each time the drill bit moves downward in the course of this vibratory movement, a force is applied thereto by the spring elements 19 tending to rotate it in a counterclockwise direction, Figure 3. This unidirectional force causes the drill to rotate with the result that the drilling is conducted in a rapid and ecient manner, and the teeth of the bit contact different parts of the hole as the drilling progresses. If desired, the spring elements can be arranged to rotate the bit in the opposite direction, i.e., clockwise, as viewed in Figure 3.

It will be evident that the described structure achieves the advantages of the invention in providing a system for operating the drill bit without the provision of a string of drill pipe, rotation of the bit in an etlicient and controlled manner 'being obtained by the engagement of the spring elements 19 with the formation at the bottom of the hole. When it is necessary to repair or replace the bit or prime mover mechanism, the drilling tool can be readily raised to the surface merely by reeling in the cable 15.

In Figures to 8, inclusive, I have shown a modified -form of the invention wherein the bit-rotating device is secured to the drill stem rather than the drill bit, and the power is supplied electromagnetically. In -this modiiication, there is an elongated drilling tool including a cylindrical stem 45 carrying a conventional drill bit 46, a reciprocatory movement being applied to the stem 45 and bit 46 by an electromagnetic motor 47 which, in turn, is suspended from a length 48 of pipe attached to the end of a flexible hose or cable 49.

Secured to the drill stem 45 or, if desired, to the motor casing is a bit-rotating device 50 having a housing 51 provided with arcuate slots 52 in which are mounted, respectively, a plurality of outwardly protruding curved blocks or ribs 53. These ribs are urged outwardly into engagement with the adjoining formation by springs 54, and each rib is provided with an enlarged inner end portion 55 for the purpose of retaining it within the slot 52'.

A cylindrical sleeve 56 is fixed to the outer surface of the drill stem 45 and is rotatably mounted with respect to the housing 51 by roller bearings 57 and 58. At the upper end thereof, the interior of the housing 51 is shaped to form a plurality of ratchet teeth 60 with which coact a pair of pawls 61. Each pawl is pivotally mounted within a recess 62 formed within the sleeve 56, and urged to an extended position by a spring 63.

As the drill stem 4S moves upwardly and downwardly in a reciprocatory manner, this movement is transmitted to the housing 51 which rotates back and `forth as it is raised and lowered due to the engagement of the ribs 53 With the formations dening the wall of the well. During the downstroke, the housing 51 rotates in a clockwise direction, Figure 8, with the result that two of the teeth `60 engage the pawls 61 and impart a rotary movement to the sleeve 56 and the drill stem 45 secured thereto. During the up'stroke, however, the housing 51 rotates in a counterclockwise direction, Figure 8, and Vthe pawls 61 slip past the teeth 60 without producing any rotation of the drill stern and drillbit. Accordingly, the bitrotating device causes rotation of the drill stem and drill bit during the downstroke but not during the upstroke.

The aforementioned reciprocating movement is imparted to the drill stern by the electromagnetic motor 47, Figure `6, which is mounted within a cylindrical casing 70. A bushing ia holds coil 71 within the casing. The coil is waterproofed by being sealed within an elastomeric insulator enclosed within a non-magnetic, corrosion proof material such as copper, Monel, or stainless steel. Within the coil is a movable hollow cylindrical armature 72. The armature is urged upwardly by a spring 73. The drill stem 45. is attached to the lower end of the armature and the interior passage of the drill stem communicates with an internal passage 72a in the armature and with the interior passage in pipe 48. Current is supplied to the coil by two leads 74- and 75, lead 74 extending to the surface through slip ring and contact sets 76, 77 and lead 75 extending to the surface through slip ring and contact sets 76 and 79.

ln operation, the drilling tool is lowered into the well and drilling lluid is circulated to the bit through the interior passages in pipe 48, armature 72 and drill stem 45. Pulses of direct current are supplied to the coil 71 through leads 74, 7S and, at each energization of the coil, the armature 72 is moved downwardly against the force of spring 73 thus causing a downward movement of the drill stem and bit to provide an effective drilling action. During the downward progress of the bit, it is rotated by the device 5d in the manner already explained.

When the current flow to the coil is stopped, spring 73 causes the armature, drill stem and drill bit to move upwardly without rotating due, again, to the described action of the device S0. Consequently, the well is drilled by reciprocating movement of the bit with rotation thereof during each downstroke. Here again, the prime mover supplying the mechanical energy to the bit is located downhole, and the use of a long drill string is eliminated `so that the drilling tool can be raised to the surface merely by reeling in the cable, without lifting and disassembling a long string of drill pipe.

While the invention has been described in connection with present, preferred embodiments thereof, it is to be understood that lthis description is illustrative only and is not intended to limit the invention.

I claim:

l. Apparatus for drilling a well which comprises, in combination, a drilling tool including an elongated drill stem, a motor connected to the upper end of said drill stem, and a bit connected to the lower end of said drill stem, means for suspending said tool in a well, means for actuating said motor to apply repetitive reciprocat'ory power impulses through said stem to said bit and thereby producea drilling action, and a device secured to said drill stem and having a member engageable with the walls of said well, said device including a housing rotatably mounted and fixed longitudinally and concentrically with said stem, a series of curved ribs protruding outwardly from said housing and dening helices therearound, means engaging said ribs and said housing for urging said ribs into engagement with the walls of said well, said housing having a series of ratchet teeth formed interiorly thereof in a plane perpendicular to the axis of the drill stem, and a plurality of ratchet pawls pivotally secured to said drill stem and engageable with said ratchet teeth to cause rotation of the drill stem with said device in one direction and not in the opposite direction.

2L Apparatus for drilling a well which comprises, in combination, an elongated tubular casing, a flexible conduit secured to the top of said casing and adapted to suspend said casing in a well, a cylindrical coil mounted interiorly of said casing, a tubular armature, means for supporting said armature for reciprocating movement within said coil, a hollow drill stem secured to said armature and extending downwardly therefrom, a drill bit secured to the lower end of said stem, means for circulating drilling iluid downwardly through said conduit, said armature and said drill stem to said drill bit, means for applying electrical energy to said coil to effect reciprocatory movement of said armature and said drill bit, and a device secured to said drill stern, said device including a housing mounted rotatable and iXed longitudinally and concentrically on said stem, a series of curved ribs protruding outwardly from said housing and defining helices thereabout, means engaging said housing and said ribs for urging said ribs into engagement with the walls of said wall, said housing having a series of ratchet teeth formed interiorly thereof in a plane perpendicular to the axis of the drill stem, and a plurality of ratchet pawls pivotally secured to said drill stem and engageable with said ratchet teeth to cause rotation of the drill stem with said device in one direction but not in the opposite direction.

3. Apparatus for drilling a well which comprises, in combination, a drilling tool including an elongated drill stem, and a bit connected to the lower end of said drill stem; means for suspending said tool in a well; means connected to the upper end of said drill stem for applying repetitive reciprocatory power impulses through said drill stem to said bit and thereby produce a drilling action; and a device rotatably mounted and iixed longitudinally on said drill stem, said device including a housing, a plurality o'f rib members mounted on said housing, each of said rib members defining a portion of a helix about said device and comprising a means for engaging the walls of the well, springs engaging said housing and said members urging said members into engagement with the walls of the well, and ratchet means connected between said device and said drill stem for effecting rotation of the housing in unison with the drill stem when the latter is moved longitudinally with the bit in one direction, but not when the drill stem is moved longitudinally with the bit in the opposite direction.

4. Apparatus for drilling a well which comprises, in combination, a drilling tool including an elongated drill stem, and a bit connected to the lower end of said drill stem; means for suspending said tool in a well; means connected to the upper end of said stem for longitudinally vibrating said stem to apply repetitive reciprocal power impulses to said bit and thereby produce a drilling action; a device rotatably supported from said drill stem and having a plurality of helical rib members engageable with the walls of the well, and means for urging said helical members into engagement with the walls of the well; and means, disposed between said stem and said device for connecting said stem to said device lfor rotation in unison therewith in a rst rotary direction responsive to said stem moving in a tirst reciprocal direction when said rib members are engaged with the walls of the well and for disconnecting said stem ifrom said device responsive to relative rotation of said device on said stem in response to said stem moving in a second reciprocal direction.

References Cited in the le of this patent UNITED STATES PATENTS 47,599 Lovegrove May 2, 1865 1,331,103 Gildea Feb. 17, 1920 1,430,473 Stoll Sept. 26, 1922 1,639,242 Versteeg Aug. 16, 192.7 1,767,286 Hinderliter June 24, 1930 1,769,921 Hansen July 8, 1930 1,899,438 Grant Feb. 28, 1933 2,589,534 Buttolph 1 Mar. 18, 1952 2,672,322 Bodine Mar. 16, 1954 2,712,434 Giles et al. July 5, 1955 2,728,556 House Dec. 27, 1955 FOREIGN PATENTS 2,443 Great Britain Jan. 26, 1905 UNITED STATES FATENT OFFICE CERTIFICATE 0F CORREGTIQN Patent No., 2979vl42 April llIk 1961 James A. Reid lt is hereby certified that error appears in the above numbered patent requiring correction and that the Said Letters Patent. should read as corrected below Signed and sealed this 24th day of-October 1961o (SEAL) Attest: l

ERNEST W. SWIDER ADAVID L. LADD Attesting Officer I Commissioner of Patents USCOMM-DCv

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