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Publication numberUS2068704 A
Publication typeGrant
Publication dateJan 26, 1937
Filing dateJul 25, 1932
Priority dateJul 25, 1932
Publication numberUS 2068704 A, US 2068704A, US-A-2068704, US2068704 A, US2068704A
InventorsPowell Leonard E
Original AssigneePowell Leonard E
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Well drilling and coring apparatus
US 2068704 A
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Description  (OCR text may contain errors)

`hun. 26, 1937. l.. E. POWELL WELL DRILLING AND CORING APPARATUS Filed July 25, 1932 3 Sheets-Sheet 1 ATTORNEY wzl/ell INVENTOR Jan. 26, 1937. E. POWELL 2,068,704

WELL DRILLING AND CORING APPARATUS Filed July 25, 1932 3 Sheets-Sheet 2 mui@ IIIIIHIIH ATTORNEY Jian. 26, 1937.

L. E. 'POWELL WELL DRILLING ND CORING APPARATUS 3 Sheets-Sheet 5 Filed July 25, 1952 INVENTOR lL L/r s ATTORNEY Patented Jan. 26, 1937 UNITED STATES PATENT OFFICE WELL DRILLING ANDCORING APPARATUS Leonard E. Powell, Dallas, Tex. A Application July 25, 1932, Serial No. 624,392 Solenne. (ci. Z55-72) This invention relates to well drilling equipment and it has particular reference to new and novel apparatus for drilling oil and other wells.

The principalobject of the .invention is to pro- 5 vide a combination of elements so constructed and arranged as to minimize the time and expense of running in and pulling out drill bits and cores. Heretofore, the'practice has been to withdraw the 'drill stem in sections, replace or repair the drill bit, coring tool or the like, extract the core and reassemble the drill stem assembly, before drilling can be resumed. Particularly in deep e wells, this conventional practice is expensive vand requires considerable time and must `be frequently tion.

The present invention comprehends the provision of an apparatus for drilling, through the medium of which a drilling or coring`unit may be introduced into the hole for the purpose of drilling either hard or soft formations, and for the taking of cores, withoutthe necessity of withdrawing the drill stem in sections. Accordingly, the drill bits can be kept in drilling condition without the usual loss of time, and faster drilling is accomplished.

` In addition to these novel features, a core barrel can be inserted to replace the core barrel filler cutter bit and samples of the stratum may lbe withdrawn with little' diiiiculty and with a great saving of time. When coring is not required, a

novel form of core barrel filler cutter is employed and the hole is drilled in the usual manner.

- Another object of the invention is to provide in an apparatus of the character specied, a novel form of bit cutter carrier of which there is a series, and a means for lowering and elevatingthe cutter carriers` into a drill collar in such manner that the bits will be successively deposited vin operative v 50 Fig. V1 .is a view in vertical cross section showing the lowerend of the drill collar and its asso- Y ciated elements.

Fig. 2 is a fragmentary view of the slotted tubular cutter supporting member.

Fig. 3-ls a fragmentary view showing a portion done, when the bit encounters hard rock forma-v of the pusher barrel for advancing the cutters in e the setting operation.

Fig. 4 is a detail fragmentary view of one of the soft formation blade cutter carriers. y

Fig. 5 is a bottom view of the tool showing a 5 set of -soft formation blade cutters in operative position.

Fig. 6 is an enlarged view of the lower portion of Figure 1 in vertical cross-section showing the assembled positions of the hard formation cutters 10 and cutter carriers.

Fig. 7 is a view in vertical section showing the upper ends of the cutter supportng member and lthe pusherbarrel, also the raising and lowering means. 15

Fig. 8 is a. detail viewof a hard formation cutter attachment which may be used in lieu of the core barrel end.

Fig. 9 is a transverse section on lines 9 9 on Fig. 7.

Fig. 10 is a transverse, section on lines Ill-I0 20 on Figure 7 l Fig. 1l is a detail view of the guide for positioning the bit cutters.

Fig. 12 is an elevation ofFigure 11, showing the drill stem in vertical cross-section;

Fig. 13 is a fragmentary sidev view in vertical section showing the relationship of the guide barrel, pusher barrel and cutter carrier barrel.

Fig. 14 is av view similar, to Figure 13, showingv the elements in a different position in the guide barrell and is an enlarged fragmentary view of the upper portion of Fig. 1.

Fig. 15 is a fragmentary view in vertical crosssection showing the cutter carrier barrel and the lmanner in which the cutters are actuated therein.

Fig; 16 is a transverse section of one of the -cutter carriers on line I6 on Figure 15.

Fig. 17 is a transverse section across the ex treme upper end of Figure 1, and

Fig. 18is a bottom view of the assembly shown in Figure 6, illustrating the relationship of the -hard formation cutters and is similar to the showing in Figure 5.

For the purpose of clarification and in support of' the objects of the invention hereinbefore set forth, it is pointed out that a special type of drill collar is provided which is suspended in the usual manner by a drill stem assembly. Within the drill stem is suspended an elongated, tubular barrel which will be hereinafter referred to as the guide barrel and whose prim'ary function is to guide the assembly, preparatory to setting the drill bits in their proper relationship in the drill collar. Within the guide barrel is another tubular member whi'ch will be hereinafter referred to as the cutter carrier barrel. This barrel, while in fixed relation with the guide barrel, is

provided with a series of longitudinal slots and. `grooves of various lengths and in each 'of which slots and grooves there is arranged to slide a flexible cutter suspension member on ilexible rod and which will be hereinafter termed a cutter carrier.

The assembly is lowered into the drill stem,

which has already been set up and the cutters in v cutters are arranged, or a core barrel about which the cutters are arranged.

When the cutters become dulled or otherwise impaired, the locking member, which it may later be termed, is withdrawn upon upward movement of the pusher barrel, and the cutters proper are successively elevated in pairs from their assembled relationship in the drill collar head.

The foregoing brief explanation is given to clarify the description for the specific construction, relationship and operation of parts to follow.

Accordingly, I designates a special type of drill collar which is threaded upon the lower section of the drill stem assembly 2, The drill collar is shown only in Figures 1, 5, 6 and 18.

The drill collar has a peculiarly shaped cutter receiving head in that it is provided with a beveled recess Whose walls are designated at a. These walls serve to receive the cutters whose carriers or suspending rods are normally under tension and when the cutters are lowered to such point where they will recede into the bevel provided therefor in the head, this-tension is relieved.

Suspended within the drill stem 2, by means of a wire line 3, is a grab and release attachment shown in Figure 7. This attachment serves to lower the invention into the drill stem, release the same for operation and elevate it when desired. The attachment is comprised of the outer barrel or casing 4, having a detachable rope socket 5 on itsupper end. Removably mounted in the barrel l is a member 6 having a series of radially spaced and depending hooks 1 which are adapted to engage under the flange 8 lof the.

tubular member 9 in ordr to lock the arms I0 in an expanded position which releases them from spear shaped member I2 when it is desired to elevate the invention.4

However, when the assembly is lowered into the drill stem, the elevator attachment is inthe position shown in Figure 7 except that bolt I1 is removed, that is to say, the arms I6, depending from the collar II which is threadedly attached to the member 9, are engaged at their lower ends under the spear shaped member I2', which extends upwardly from the weight stem I3. A series of arms I4 are also provided in parallel relation to the depending arms I6 and have flared lower ends I5 which normally repose on the conical surface of the spear I2. Thus, when Vthe lowl er end of the barrel 4 is allowed to advance against the annular stop I6, carried by the weight stem I3, the ends I5 vof the arms Il will spread and in so doing, they will engage and expand the lower ends of arms I0, thereby releasing the hooks carried thereby from engagement beneath the bottom of the spear I2. Also when the pin is removed, the lower portion of the member 6, which, as apparent in Figure 7 is of tubular shape and shouldered, may slide further down into the member 9, which is correspondingly shouldered.

Thus it may be seen that the upper viingers- 1, carried by the upper portion. of member 6 will engage under the flange 8 of member 9 and being thus locked, will, through the release of the grab mechanism comprised of the lower arms I6 and spear I2, release the assembly.

In the raising operation, however, the pin I1, which locks the lower portion of member 6 in fixed relation with the member 9 is put in place through the opening I8 in the barrel 4 provided ior this purpose. However, when it is merely a matterrof lowering the assembly, the pin I1 is removed from position since it serves the purpose Figure 1. l

It will be understood that the pusher barrel 23, which, as apparent in Figure 1, is disposed betweenthe guide' barrel I9 and cutter carrier barrel 20, is capable of sliding movement up-and down between these barrels, butvdue to the webs 22, shown in Figure 17, is incapable of independent rotation. Slots 26 in the barrel 23, which receive the webs 22, prohibitv such rotation.

From the foregoing, it is apparent that the barrels I9, 26, and 23 Aare in concentric relationship with the drill stem and that the guide barrel I9 is fixed with the carrier barrel 26 and hase. beveled lower end 25, as shown in Figures 1 and 6, corresponding with a bevel in the upper portion of the drill collar I. These correspondving bevels are effective for insuring proper alignment of the assembly with the cutter drill collar, as well as a tight t when in place in the drill collar. It is also apparent that the intermediate pusher barrel 23, which is -suspended from the weight stem I3, is constrained to move perpendicularly in the operation of assembling the cutters in the head.

Referring specifically to the construction of the pusher barrel 23, it is pointed out that this barrel has a series of narrow, exble strips 26 cut out of its sides and these strips are only half the thickness of the walls of the barrel proper. This is shown clearly in Figures 13 and 14. The fact that these strips are'thinner than the sides of the barrel not only lends flexibility to the strips but also defines a channel 21 therebehind, in which slides the lugs 28 carried by the upper end of each of the cutter carriers or Shanks 29 from which is suspended the cutters 30. A deures 1 and 6 is slotted from its lower end upward-j* 1y, the slots being designated by the common reference character 3I vand exemplied in Figure 2.

These slots terminate at unequal points intermediate between the ends of the barrel and as indicated by the dotted lines in Figure 2, the upper portions 32 of the slots are dove-tailed in cross-section. This is also apparent and perhaps more clearly shown in Figures 18 and 17.

Each slot 9I is longer than the length of the shank disposed therein to permit of retraction since the shanks are of necessity of unequal lengths and ,but a portion of each reposes in its respective slot and each is required to be moved through a distance greater than its length.

The purpose of the dove-tailing of the slots 22 is in order to receive the correspondingly shaped upper ends `of the shanks 29 of the cutting elements 39 and allow the shanks to slide up -and down without-becoming released from the slots. On the extreme uppervend of each shank 291s an outwardly projecting lug 28, men-- tioned previously, and by bearing upon this lug, Y

the4 shank will slide downwardly, thereby urging the cutting element carried thereby into position in the drill collar. To accomplish this, the narrow, exible strips 26 of the pusher barrel 2 3 are provided with lugs 33 which are urged against the lugs 28 of the shanks 29 and as the pusher'barrel 23 is lowered into the space between the guide'barrel I9 and the cutter carrier barrel 29, the lugs 33 come successively into engagement with the lugs 28 of Vthe shanks 29 and since the barrels I9` and 20 are stationary when this operation occurs, the shanks are moved to a point predetermined by their lengths to bring the cutters 39 to the proper position in the drill collar head I and due to the flexibility of the shanks 29 and to the fact that they are under a continuous tension while suspended in the barrel 20, asgshown particularly in Figure 15, the suddenl release oi' this tension, as the cutter moves under the .bevel a in the drill collar head I, is sufficient to cause the cutter to adjust itself in its respective place in the head preparatory to the successive setting of the remaining cutters. With particular reference to Figures` 13 and 14, it is pointed out that the guide barrel I9 has a number of interior, longitudinal grooves 34 corresponding to the number of cutter shanks 29 and of corresponding lengths. In other words, the shortest groove 34 will be of such length as to accommodate the shortest shank 29 and will be in register therein. This is also true of the remaining grooves and shanks around the barrels. Therefore, when the lugs 28 upon the ends o! the shanks 29 are all disposed in the yopenings 35 below the exibie strip 26A of Ithe pusher barrel 23, (see Figure 3), movement of the barrel 23 up and down will accordingly move the shanks 29. However, as the lugs 33, on the lower ends of the iiexible strips 26 of the barrel 23 ride4 into the interior grooves 34 of the guide barrel I9, as shown in Figure 14, tension thereon is relieved and they immediately fall within the grooves, which action causes the lugs 28 of the shanks 29 to be released to the position shown in Figure 14, in which position the cutters 30 are in assembled position in the drill collar head I.

When all of the cutters 39 are assembled operativeiy inv the drin head-or mgm collar l, as shown in Figure 18, they must b locked in such position. vThis is accomplished bymeans of the member 88, of the core barrel assembly 31 'connected ,to the weight stem I3. The member 36 serves the dual purpose of locking the cutter assembly and-"forming'the lower end of the corevhead I2 of the member I6.

served that the lower end of themember 29, is beveled at b to correspond with the bevel c of the cutters 30. This arrangement insures a locked condition of the cutters when assembled in the head i.

Within the drill stem 2 is arranged a guide iiange 39 which may be seen in Figures 6, l1 and 12. The construction and arrangement of this ange is obvious but it is speciically pointed out that an opening 40 is provided in the lower end. It will also be noted in Figure 17 that the barrel I9 has a lug 4I integral with its exterior, as the barrel I9 is lowered into the drill collar, lug 4I contacts with the flange 39 and it rotates to such positionv that the lug 4I will pass through the opening of the ange 39, thereby bringing the elements into proper alignmentwith the head I, preparatory to the cutter assembling operation. Reference is alsomade to the spring guides 42, affixed to the exterior of the barrel I9 and slidingly engaging lthe interior walls of the drill stem 2 to effect centering of the barrel I 9.

When the cutters are assembled and drilling is proceeded with, drilling iluld is passed into the hole through water courses 43, shown in Figure 6; this drilling fluid is prevented from entering the assembly by the valve 44, shown only in the lower portion of Figure 7 and which also acts as an escape 'for any foreign matter collected in the core barrel as the core enters.

In operation, the lowering mechanism shown lin Figure 7 is connected as illustrated vand suspends the barrel 23 and the tubing 3l carrying `the corin'g and locking member 36. The locked and 20 will cause the lugs 33 carried by the iiexible strips 26 of barrel 23 to engage the outwardly projecting lugs 28 of the shanks 29, carrying the cutters 30, and as the pusher barrel 23 continues wto move downward, the shanks 29 are urged downwardly until the cutters 30 are successively arranged in operative position in the head I. The elevator is then released and withdrawn from drill pipe after which operation the kelly joint is connected and drilling proceeded with.

When it is desired to elevate the assembly, the elevator is lowered into the drill stem 2 with the pin or bolt I1 in place which allows the arms I9 to spring outward and clamp under the spear Thus the entire assembly may be elevated.

The arrangement of the cutters 30 in the head as shown in Figure 18 as well as in Figure 5, provides a central l'space for the reception of a coring tool if it is required to take a core during the drilling operation. Moreover, there is no limitation intended by the specific showing of the rotary cutters shown in the several views since cutters ofthe type illustrated in Figure 5 may be employed if the character formation encountered demands.

Manifestly .the construction shown and described is capable of considerable modification and such modiiication as is considered within the scope and meaningA of the appended claims is also considered within the spirit and intent of the invention.

In the foregoing specifications wherein the Words assembly and invention are separately employed they are synonymous except where assembly is modified by the association therewith of another term such as core barrel assembly, cutter assembly and like expressions,

leach of which is to designate lbut a part of the complete assembly or invention.

What is claimed is:-

1. Apparatus for drilling and coring wells including a drill collar and head, a plurality of concentric pipes, the inner pipe comprising a cutter carrierl barrel and having longitudinal guide slots in its sides of varying lengths,` a series of cutting elements having shanks of varying lengths corresponding to the 'lengths of and guided in said slots and whose free ends are bent outwardly, means to engage successively the bent ends of said shanks whereby to urge said cutting elements into operative position and `means for successively withdrawing said cutting elements.

2. Apparatus for drilling wells including inV combination, a drill stem assembly, a drill collar attached thereto at its lower end and having a recessed head, a cutter assembly comprising a series of concentric pipes within the drill stem, the inner pipe comprising a cutter carrier barrel and having longitudinal slots of different lengths in its sides terminating in stepped relationship intermediate its ends, disposed'within said cutter carrier barrel when in retracted position, a series of exible shanks of varying lengths in accordance with the lengths of the slots in said cutter carrier barrel, each of said shanks having a cutter element in its lower end and having its other orfree end mounted in one of.

said slots for constrained slidable movement therein, means for urging said shanks downwardly into operative position in recesses in said head, means for collectively locking the shanks in operative position and means for successively withdrawing said Shanks from operative position in the head into the cutter carrier barrel.

3. Apparatus of the character described in.

cluding in combination, a drill stem assembly, a drill collar having a recessed head, a barrel having longitudinal slots in its sides terminating in stepped relationship intermediate its ends, a

guide barrel surrounding said slotted barrel andl in concentric and fixed relation thereto, a series of rotary cutting elements having flexible shanks of varying lengths in accordance with the lengths of the slots in said slotted barrel and whose freeV ends are arranged Ato slide in said slots, flexible means arranged to be lowered in said drill stem assembly to engage successively the free ends of said shanks `whereby to urge said cutting ele-' 4. Apparatus of the character described in- I cluding in combination, a drill stem assembly, a

drill collar having a recessed head, a barrel having longitudinal slots in its sides terminating at unequal points intermediate its ends, a guide barrel surrounding said slotted barrel and in fixed relation thereto a series of cutting elements having flexible Shanks of varying lengths in accordance with the lengths of the slots in said slotted barrel and whose free ends are constrained to slide in said slots, means arranged to be lowered in said drill stem assembly to engage successively the ends of said Shanks whereby to urge said cutting elements successively into operative position in said drill collar, means for locking said cutting elements in assembled relationship in said head and means for successively withdrawing said cutting elements.

5. Apparatus for coring and drilling wells including a drill collar having a recessed head and a series of confined drilling elements, a tubular member for slidingly and exibly suspending said elements for movement into radial relation in said head to define a central opening, means embracing and slidable over said tubular member for moving said elements, and means receivable in said opening for collectively locking said drilling elements.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3437159 *Sep 30, 1966Apr 8, 1969Christensen Diamond Prod CoRetractable drill bits
US3554304 *Feb 10, 1969Jan 12, 1971Christensen Diamond Prod CoRetractable drill bits
US3692126 *Jan 29, 1971Sep 19, 1972Rushing Frank CRetractable drill bit apparatus
US5662182 *Jun 15, 1994Sep 2, 1997Down Hole Technologies Pty Ltd.System for in situ replacement of cutting means for a ground drill
US5743344 *Jun 7, 1995Apr 28, 1998Down Hole Technologies Pty. Ltd.System for in situ replacement of cutting means for a ground drill
US5785134 *Jun 7, 1995Jul 28, 1998Down Hole Tech Pty LtdSystem for in-situ replacement of cutting means for a ground drill
US5813481 *Jun 7, 1995Sep 29, 1998Down Hole Technologies, Ltd.System for in situ replacement of cutting means for a ground drill
US5954146 *Jun 7, 1995Sep 21, 1999Down Hole Technologies Pty. Ltd.System for in situ replacement of cutting means for a ground drill
US8668031 *May 28, 2009Mar 11, 2014Schlumberger Technology CorporationDrill bit and method for inserting, expanding, collapsing, and retrieving drill bit
US20110120774 *May 28, 2009May 26, 2011Thrubit B.V.Drill Bit and Method for Inserting, Expanding, Collapsing, and Retrieving Drill Bit
U.S. Classification175/259, 175/332, 175/397, 175/363, 175/286, 294/99.1, 175/260, 294/86.32
International ClassificationE21B10/66, E21B25/00, E21B10/00, E21B25/04
Cooperative ClassificationE21B10/66, E21B25/04
European ClassificationE21B25/04, E21B10/66