US2470695A - Cone type well drilling bit - Google Patents

Description

May 17, 1949 Js. GOODWIN E-rAl. 2,470,695

TYPE 'Win31, DBILLING BIT Filed Nov. 17, 1947 sheets-sheet 1 t? mn-7% A3 t? 3 E,` s z F5 TTBNEP J. s. .GQODWIN Erm,

May 17, 1949.`

CCNE TYPE' WELL DRILLING BIT 2 Sheets-Sheet 2 Filed NOV. 17, 1947 /lll/ Patented May 17, 1949 'iilT OFFICE CONE TYPE WELL DRHLLING BET John S. Goodwin and Charles E. Whittaker,

Whittier, Calif., assignors to Globe Oil Tools Company, Los Nietos, Calif., a corporation of California Application November 17, 1947, Serial No. 786,516

(Cl. Z55-71) Claims. 1

This invention has to do with a cone type well drilling bit, and it is a general object of the invention to provide a simple, practical, highly effective bit for drilling wells with the rotary method.

A general object of the present invention is to provide a cone type bit involving a pair of diametrically opposite cones at the working end of the bit supported by ball and roller bearings .so disposed as to withstand working pressures in a most advantageous manner.

Another object of the invention is to provide a bit of the character referred to in which the two c'onical cutters are substantially balanced in cutting action while only one of the cutters er:n tends to and operates at the center of the bore.

A further object of the invention is to provide a bit of the general character referred to in which the two cutters are related to cut diiferent portions of the bore except at the periphn eral portion of the bore where they both cut on the bottom and on the side of the bore to maintain the desired bore diameter. The portion of the bore at which both cutters operate is the portion of the bore at which the greater portion of the cutting action occurs.

Another object of the present invention is to provide a bit of the general character referred to in which the conical cutters are shaped and pitched to cut the bore so a central conical -projection is maintained at the bottom of the bore serving to stabilize the bit and prevent undesirable deflection of the bit in the course ci drilling.

It is another object of the present invention to provide a bit of the character referred to wherein a conical cutter is mounted on a supporting projection through a bearing assembly involving an annular series of ball bearings introduced into place through a bore or channel normally plugged by a closure, the inner end oi which is shaped to form a part of the ball supm porting race.

A further object of the invention is to provide a bit of the character referred to involving a simple, compact cutter mounting through which the cutters are meshed together and are secured to the legs of the body by simple, effective welding.

The various objects and features of our invention will be fully understood from the following detailed description of typical preferred forms and applications of the invention, throughout which description reference is made to the ac companying drawings, in which:

Fig. 1 is a side elevation of a bit embodying the present invention showing it applied to the lower end of a drilling string, the said part of the string being shown in section. Fig. 2 is a view similar to Fig. 1 taken in the direction indicated by line 2-2 on Fig. 1. Fig. 3 is an enlarged vertical sectional view of the bit construction of the present invention, being an enlarged sectional view taken as indicated by line 3-3 on Fig, 2. Fig. 4 is a transverse sectional view taken as indicated by line 4-4 on Fig. 3. Fig. 5 is a transverse sectional view taken as indicated by line 5 5 on Fig. 3. Fig. 6 is a transverse sectional view taken as indicated by line B--S on Fig. 3. Fig. '7 is a sectional view taken as indicated by line 'l-l on Fig. 3. Fig. 8 is a sectional view taken as indicated by line 8-8 on Fig. 3. Fig. 9 is a view similar to Fig. 3, showing a modied construction, one cutter of the construction being shown in section while the other is shown in elevation, and Fig. 10 is a detailed view taken as indicated by line llll0 on Fig. 9.

The bit embodying the present invention and shown in Figs. 1 to 8, inclusive, involves, generally, a body A characterized by depending diametrically opposite legs I0, two similar cutters B and C, mounting pins D for the cutters, and bearing means E by which the cutters are supported on the pins.

The body A serves primarily as a carrier for the cutter supporting pins and is applicable to the lower end of the well drilling string S so that fluid therefrom is directed in a most advantageous manner to the working or cutting parts of the cutters. The particular body A illustrated in the drawings involves a main portion l2 which is substantially round in cross sectional configuration, diametrically opposite legs lll depending from the main portion I2, and a coupling part or pin i3 projecting upwardly from the portion i2. In the case illustrated the pin I3 is externally threaded to be threaded into the lower end of the operating string S. It is to be understood that any suitable or convenient means may be provided for making the desired connection between the bit and the operating string.

The legs lo which are preferably in the form of integral extensions of the main portion I2 of the body are located diametrically opposite each other and depend from the body so that they extend downwardly and outwardly therefrom. The inner sides of the legs are nished flat at lli and extend downwardly .and outwardly at an angle of about from the vertical aXis of the bit. The outer parts or surfaces of the legs may be shaped in any suitable manner, for instance, as shown in the drawings, the outer sides l5 may be curved concentric with the central axis of the bit.

The two cutters B and C, although not alike, are preferably mounted on the legs I9 through like mounting pins D and bearing means E. The pins and bearing means support the cutters so that they extend downwardly and inwardly and are in meshed relation, as clearly illustrated in Figs. 1 and 3 of the drawings. The cutters themselves are so formed and related as to mesh together without interfering with each other, and so that they out the formation in a manner to establish a bore of the desired diameter with a central conical projection on the bottom surrounded by a peripheral portion that tapers or is inclined upwardly and outwardly from the base of the conical projection.

The mounting pins D are preferably alike and are integrally joined to the legs l0 in like manner so that they project from the inner sides lll of the legs on axes normal to the said sides of the legs. Each mounting pin D is an elongate element involving a shank portion 2l! of substantial diameter projecting from a base portion 2i. A tip 22 of reduced diameter projects from the outer end of the shank portion and a head 23 projects from the base portion 2l to serve as a part by which the pin is joined toits supporting leg.

The base portion 2l of the pin is a part slightly larger in diameter than the shank portion 2l] and is of limited axial extent as will appear from the drawings. The base of the pin seats or bears upon the inner side i4 of the supporting leg l0 and, in practice, the said sideA of the leg may be provided with a base supporting boss as clearly illustrated in the drawings. The shank portion of the pin is made as large in diameter and as long as practical, in order to afford a substantial cutter mounting.

The preferred form of bearing means E illustrated in the drawings involves an annular series of inner rollers 30, an annular series of outer rollers 3|, and an annular series of balls 32 between `the two series of rollers. When this particular or preferred bearing means is employed the shank portion 20 of the pinis provided adjacent the base portion 2| with a roller receiving groove 33 accommodating the inner rollers 30, and it is provided with .a ball receivingV groove 34 intermediate the groove 33 and the outer end of the shank portion,- the outer rollers 3l having engagement with the tip portion 22 of the pin.

The groove 33 has an axially disposed bottom on which the rollers operate, and has radially disposed end walls 35 that conne therollers against axial displacement. The ball receiving groove 3@ is rounded, being curved about a common c-enter to be spherically curved, forming a race in which the balls 32v operate. The cutters that are carried by the pins are generally-conicalv in formation and the pins are extended as far as possible into the cutters. Because of the conical formation of the cutters it is advantageous to make the tip 22 of the pin substantially smaller in diameter than the shank 20 and the outer rollers 3l may be smaller invdiameter and shorter than the inner rollers 30, as clearly shown in Fig. 3 of the drawings.

The head 23 of the pin projects from the base 2l through a notch 4E) formed in the leg l0 and extending upwardly into the leg from its outer or lower end. Thenotch is enlarged at the outer side I5 of the leg I0 to form a recess or socket di at least partially, and preferably entirely, surrounding the notch 40. The head 23 of the pin extends into the recess 4I, and, as illustrated, the head is flattened and presents hat sides 44 extending parallel with the vertical sides l5 of the recess. The upper edge [S5 of the head is shown straight and is substantially parallel with and spaced from the upper wall 4l of the recess.

In accordance with our invention we employ welding W to bond the pin D to the supporting leg and in order to provide for a substantial and effective weld or body of welded material W we make the recess 4l in the leg considerably wider and higher than the head 23, so that there is a substantial space between the at sided head and the walls of the recess. In the case illustrated we pitch or incline the walls of the recess to provide an outwardly aring or trough-like space to receive the weld W. When this construction is employed a single continuous weld extends through the recess at both sides of the head and at the top edge of the head, the weld being bonded to the leg l and also to the head of the pin. It is to be understood that in practice the weld, as shown in the drawings, may be established in the'recess to occupy the recess and possibly projectsomewhat therefrom, and to possibly have a portion overlying the end of the head 23, after which any excess welding can be dressed off.

Each of the cutters has a socket or bore 5U entering it from its base or large end to receive the shank and tip of a mounting pin. The bore 5@ that enters the cutter from the base end is enlarged at il immediately adjacent the base end and opposite the groove 33 in theV pin to cooperate with the groove 33 in establishing a space between the pin and cutter to accommodate the rollers 3S. Between the enlarged portion 5I and the bottom of the bore 5i! the cutter is provided with a groove 53 that occurs opposite the groove 34 in the pin, the groove 53 being rounded or having a curved face and cooperating with the groove 3d to form a channel accommodating the balls 3Q. A bore 55 of reduced diameter continues from the bottom of the bore 5G receiving the tip 22 of the pin, the bore 55 being larger than the tip of the pin toaestablish a space to accommodate the outer rollers 3l.

In accordance with our invention a passage 60, preferably a bore, is provided in the pin to facilitate introduction of the balls 32 into the registering grooves 34 and 53. In the form of the invention under consideration the passage extends frorn the outer end of the head 23 through the pin to the bottom of the groove 34 where it opens into the groove 34;

A closure preferably in the form of a plug elv normally occupies the passage and has an inner end 62 rounded or curved about a common center to be spherically curved and in register with the spherically curved wall of groove 34 to form a continuation of the ball race established by the groove 313. An orienting pin 63 extends through the plug el and into the head 23 positively orienting the plug with the end surface 52 in the proper position. The plug 6| is preferably made secure or fast in the oriented position as by welding 54. In the case illustrated the plug SI is made somwhat shorter than the passage l so that it does not occupy the outer end portion of the passage leaving this portion of the passage to accommodate or receive the welding 64, as shown in Fig. 3 of the drawings.

By providing the orienting pin 63 we may be able to introduce the plug 6I into place in the passage 60 either before the groove 34 is formed or after the groove 34 has been formed in the pin and then dress or form the end 62 of the plug either as the groove 34 is formed or by dressing down that portion of the plug that projects into the groove 34. With the plug 6I thus located in the passage with its inner end 62 shaped to conform to the ball race the orienting pin 63 is removed and the plug removed, facilitating introduction of the balls between the pin and cutter after which the plug can be reinserted and the orienting pin installed, reestablishing the plug in proper position.

The cutters B and C may be referred to generally as cone-type cutters, each being characterized by a base portion of substantial diameter, from which a conical portion projects inwardly and downwardly in the assembled bit, as shown in Fig. 3 of the drawings. The cutters B and C are similar but not identical or alike, the cutter B being characterized by a true conical portion projecting from the base, the cutter C being characterized by a truncated conical portion which is not a full cone but merely a frustrum of a cone.

The cutter B is mounted on pin D carried by one leg I of the body with its base portion adjacent the inner side I4 of the leg and with its axis coincidental with that of the pin, to the end that the cutter extends downwardly and inwardly toward the center and lower end of the bit. It is a feature of the bit being described that the cutter B extends to and somewhat beyond the central axis of the bit in the direction of the cutter C and in like manner the cutter C extends down and in from its supporting leg beyond the center of the bit in the direction of cutter B, so that the cutters B and C overlap or mesh together, the cutters being so constructed as to permit of such meshing or overlapping.

The base portion of cutter B is made as large as possible in diameter to project well beyond the lower end of the supporting leg both downwardly or axially and outwardly or radially. The base portion of the cutter has a portion X extending substantially parallel with the axis of the cutter and acting on the bottom of the well bore at the periphery thereof or outward of the conical center left by the bit. The base portion of cutter B also has a beveled part Y which joins part X and extends vertically from the point where part X engages the bottom of the well bore and serves to engage the wall of the bore and maintain the bore at the desired diameter.

The cutter B has a truly conical portion extending from the base and terminating in a tip or apex part Ill which projects past or beyond the center of the bit in the direction of cutter C and, consequently, serves to act on or to engage the center of the well bore. The cutter B is characterized by annular or circumferential grooves so located and proportioned as to receive or accommodate the projecting portions of cutter C. The particular cutter B shown in the drawings has a groove 'li in the conical portion and a groove 'I2 where the conical portion ,loins the base portion. It is to be understood, of course, that the several parts of the cutter B not relieved or removed by the grooves il and l2 may be notched as at 'I3 and M so that they are toothed, the notching preferably being such as to establish relatively sharp crests 'I5 such as to have effective cutting action. The cutter C has a base portion X' similar, generally, to the base portion X of cutter B and it has a portion Y' corresponding to the portion Y of cutter B. The conical portion of cutter C projecting from the base portion is not a full cone but is merely a frustrum of a cone, the tip or apex portion being removed or cut away leaving a flattened end portion and permitting the tip or apex portion 'I0 of cutter B to, in effect, overlap or extend into what would otherwise be the Zone of cutter C. Cutter C is provided with grooves similar to those of cutter B but located differently in order to accommodate the Iprojecting portions of cutter B. A groove IIa is provided in the conically shaped portion of cutter C at a point to accommodate the portion of cutter B occurring between the grooves 1I and 12 of cutter B. A second groove '52a is provided in the portion X' of cutter C and is removed from the point 8| where the base portion of the cutter joins the conically shaped portion leaving a portion of cutter C to cut at the zone where the upwardly and outwardly tapered or pitched peripheral bottom of the bore joins the central conical projection at the bottom of the bore. It will be observed that the base portion of cutter C is notched as at 13a establishing teeth, while the conically shaped -portion is notched as at 'lll-a to establish teeth thereon. It will be apparent from Fig. 3 of the drawings how the cutters shaped and related as above described have overlapping or meshing engagement at the center of the bit where the meshing or overlapping por tions of the cutters extend substantially vertically.

In accordance with the preferred form of our invention the pins extend downwardly and inwardly from the legs of the body at an angle of about 35 from the horizontal and the cutters are shaped and proportioned so that the conical portions thereof have greater length radially in engagement with the bottom of the well bore than do the base portions of the cutters. Further, the cutters are shaped, mounted and related so that the conically shaped portions of the cutters establish angles of about 18 with the horizontal and thus act to establish a conical central projection in the bottom of the well bore, while the parts X and X of the base portions 0f the cutters extend upwardly and outwardly at angles of about 30 from the horizontal where the cutters engage the bottom of the well bore and thus act to form an upwardly and outwardly inclined or pitched peripheral. portion at the bottom of the bore outward of the central conical projection and extending between the conical projection and the side wall of the bore.

The body A of the bit is joined to the operating string S through the coupling pin I3 so the bit receives circulation fluid from the operating string. In accordance with the preferred construction the pin I3 has a central opening 85 in communication with the operating string-r while the main portion I2 of the body has a central opening 86 directing fluid from the opening 85 straight down into the central meshing portions of the cutters B and C. Additional side openin-gs 81 are preferably provided in the body por tion I2 which openings 8l' are so located and shaped as to direct uid onto the base portions of the cutters in a most advantageous manner.

In the form of the invention illustrated in Figs. 9 and 10 of the drawings the body A may be the same as that above described while the 7... mounting pins D' andy cutters B and C" are some what different in formation. The pins D are preferably alike and each involves a shank portion 2lla, a head 23a anda tip 22a. The shank portion in this form of the invention is outwardly tapered or conically formed at Sli whe-re it is provided with a ball receiving groove 3d in other respects the pin D may be similar to the pin D hereinabove described. In this form of the invention the balls 32a are introduced between the cutter and pin, not through the pin but rather through the cutter, the cutter being provided with a radial ,passage iiiie closed by a plug B la. The plug has an inner end @2a rounded to be curved about a common center to forni a part or continuation of the curved race in the cutter, the cutter being provided with a curved groove 53a establishing the race for the balls 32a. The plug 6 Ial is provided at its outer end with a projecting portion 63 that may be marked or which may so project as to facilitate orientation o the pin with the surface 52a in the proper posi tion, Welding @da secures the plug in place in the cutter.

In the form of the inventiony shown in Fig. 9 the cutters are preferably both characterized by a base from which a conical portion projects and they are generally alike except that they are grooved to establish rows of teeth at dierent positions and which are such that they will not track on the bottom of thewell` bore. The cutter B has grooves 'I IlD and 12b in the conical portion and base portion, respectively, while the cutter C- has grooves llc in the conical portion and a groove "52C in the base portion, the grooves in the two cutters being so located that they do not occur at the same points on the cutters, but in this case the cutters do not mesh or lap together, but rather are sinall enough so that they do not extend to or overlap the central axis of the bit, but rather inerely closely approach it, as shown in the drawings.

iiaving described only typical preferred forms and applications of our invention, we do not wish to be liniited or restricted to the specific details herein set forth, but wish to reserve to ourselves any variations or nodications that may appear to those slrilled .in the art and fall within thev scope of the following claims.

Having described our` invention, we claim:

l.. in a bit of the character described, a body having a depending leg, a notch extending upwardly into the lower end of the leg, said notch being enlarged at the outer side of thev leg to form a recess atleast partially surrounding the notch, a cutter carrying pin having a head extending through the notch and into the recess and engaging the walls of the notch, and welding material occupying the recess and bonding the head to the leg.

2. In a bit of the character described, a body having a depending leg, a notch extending upwardly into the lower end of the leg, said notch being enlarged at the outer side of the leg to form a recess at least partially surrounding the notch, a cutter carrying pin having a base engaging the inner side of the leg and a head extendingY through the notch. and into the recess and engaging the walls of the notch, and welding material occupying the recess and bonding the head to the leg.

3. In a bit of the character described, a body having a depending leg, a notch extending upwardly into the lower end of the leg, said notch being enlarged at the outer side of the leg to'form a recess at least partially surrounding the notch,-y

acutter carrying pin having a flat sided head extending through the notch and into the recess and engaging the walls of the notch, and welding material occupying the recess and bonding the head to the leg.

4. In a bit of the character described, a body having a depending leg, a notch extending upwardly into the lower end of the leg, said notch being enlarged at the outer side of the leg to form a-,recess at least partially surrounding the notch, a. cutter carrying pin having a base engaging the inner side of the leg and a flat side head extending through the notch and into the recess and engaging the walls of the notch, and welding material occupying the recess and bonding the head to the leg.

5. In a bit of the character described, a body havinga depending leg, a notch extending upwardly into the lower end of the leg, said notch being enlarged at the outer side of the leg to form a recess at least partially surrounding the notch, a cutter carrying pin element having a head extending through the notch and into the recess and engaging the walls of the notch, welding material occupying the recess and bonding the head to the leg, a cutter element, anti-friction means mounting the cutter element on the pin element, said anti-friction means including registering grooves on the pin and cutter elements forming a ball race, balls in said ball race, one of said elements having a ball passing bore therein extending to said ball race, a plug closing the bore and having its inner end forming a continuation oi the wall of the ball race, and weldingmaterial retaining said plug in said bore.

6. A Well drilling bit including a body having diametrically opposite depending legs, a notch extending upwardly into the lower end of each said leg, each said notch being enlarged at the outer side of the leg to form a recess at least partially surrounding the notch, cutter carrying pins each having a head extending through one of said notches and into the recess and engaging the walls of the notch, welding material occupying the recesses and bonding the heads to the legs, two cutters, one cutter being in the shape of a cone and extending across the center of the bit and the other cutter being in the shaper of a frustum of a cone with the tip of the first mentioned cutter adjacent its outer edge, the

conical portions of the cutters being meshed together at the center of the bit, and anti-friction means mounting the cutters on the pins.

7. A well drilling bit including a body having diametrically opposite depending legs, a notch extending upwardly into the lower end ci each said leg, each said notch being enlarged at the outer side of the leg to form a recess at leastv partially surrounding the notch., cutter carrying pins each having a head extending through one of said notches and into the recess and the walls of the notch, said pins having flanges engaging the inner sides of the legs, welding material occupying the recesses and bonding the heads to the legs, two cutters, one cutter being in the shape of a cone and extending across the center of the bit and the other cutter being in the shape of a frustum of a cone with the tip of the rst mentioned cutter adjacent its outer edge, the conical portions of the cutters being meshed together at the center of the bit, and antifriction means mounting the cutters on the pins. 8. A well drilling bit including a body having diametrically opposite depending legs, a notc extending upwardly into the lower end of each said leg, each said notch being enlarged at the outer side of the leg to form a recess at least partially surrounding the notch, cutter carrying pins each having a flat-sided head extending through one of said notches and into the recess and engaging the walls of the notch, welding material occupying the recesses and bonding the heads to the legs, two cutters, one cutter being in the shape of a frustum of a cone with the tip of the first mentioned cutter adjacent its outer edge, the conical portions of the cutters being meshed together at the center of the bit, and anti-friction means mounting the cutters on the pms.

9. A well drilling bit including a body having diametrically opposite depending legs, a notch extending upwardly into the lower end of each said leg, each said notch being enlarged at the outer side of the leg to form a recess at least partially surrounding the notch, cutter carrying pins each having a nat-sided head extending through one of said notches and into the recess and engaging the walls of the notch, said pins having iianges engaging the inner sides of the legs, welding material occupying the recesses and bonding the heads to the legs, two cutters, one cutter being in the shape of a cone and extending across the center of the bit and the other cutter being in the shape of a frustum of a cone with the tip of the rst mentioned cutter adjacent its outer edge, the conical portions of the cutters being meshed together at the center of the bit, and anti-friction means mounting the cutters on the pins.

10. A well drilling bit including a body having diametrically opposite depending legs, a notch extending upwardly into the lower end of each said leg, each said notch being enlarged at the outer side of the leg to form a recess at least partially surrounding the notch, cutter carrying pin elements each having a head extending 10 through one of said notches and into the recess and engaging the walls of the notch, Welding material occupying the recesses and bonding the heads to the legs, two cutter elements, one cutter element being in the shape of a cone and extending across the center of the bit and the other cutter element being in the shape of a frustum of a cone with the tip of the rst mentioned cutter element adjacent its outer edge, the conical portions of the cutter elements being meshed together at the center of the bit, anti-friction means mounting the cutter elements on the pin elements to provide two assemblies of pin and cutter elements respectively, said anti-friction means including registering grooves on the pin and cutter elements of each said assembly forming a ball race for each said assembly, balls in each said ball race, one of the elements oi' each said assembly having a ball passing bore therein extending to the ball race, a plug closing each said bore and having its inner end forming a continuation of the wall of `the ball race, and welding material retaining said plugs in said bores.

JOHN S. GOODWIN. CHARLES E. WHITTAKER.

REFERENCES CITED The following references are of record in the nie of this patent:

UNITED STATES PATENTS Number Name Date 2,058,624 Reed Oct. 27, 1936 2,058,625 Reed Oct. 27, 1936 2,064,273 Scott Dec. l5, 1936 2,104,819 Schlumpf et al. Jan. 11, 1938 2,104,820 Scott Jan. 11, 1938 2,126,041 Reed Aug. 9, 1938 2,147,927 Scott Feb. 21, 1939 2,318,370 Burch May 4, 1943 2,444,724 Brown July 6, 1948

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