US2886293A

US2886293A - Directional well bore roller bit

Info

Publication number: US2886293A
Application number: US480830A
Authority: US
Inventors: Charles J Carr; James B Washburn
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-01-10
Filing date: 1955-01-10
Publication date: 1959-05-12
Anticipated expiration: 1976-05-12

Description

C. J.. CARR EI'AL lDIRECTIONAL WELL BORE RLIJTR BIT May 12, v1959 Filed Jan. 1o, 1955 35 INVENTUM, vi1/maf: .Z klee .J2/w55 Wr/Mae# May 12, 1959 C'. .1. CARR Erm. 2,886,293

' DIRECTIONAL WELL BoRE ROLLER BIT Y 2 sheets-sheet 42 22. me? Si 77 84 7a a4 @5f INVENToRs,

ras/vr vnr United States Patent C DIRECTIONAL WELL BoRE ROLLER BIT Charles J. Carr, Long Beach, and James B. Washburn, Lomita, Calif.

Application January 10, 1955, Serial No. 480,830

' s Claims. (ci. zss-sls) This invention has to do with a well drilling bit and it is a general object of the present invention to provide a well tool construction wherein the active parts or cutters of the tool are particularly adapted for use in directionally cutting a well bore to a specified gauge.

Thisapplication is iiled as a continuation-in-part of our now abandoned, application Serial No. 428,336 entitled, .Bore Reaming Roller Bit, led May 7, 1954.

It is a primary objectof this invention to provide a well boring roller bit which acts to eiectively penetrate the earth formation and which acts to gauge the well bore at the bottom thereof. In the tool of the present invention there are cutters which simultaneously act upon the side wall of the well bore as well as upon the bottom thereof.

An object of this invention is to provide a cutter construction for a well drilling tool of the character referred to, which has cutting action on the bottom and the sides of the lower end portion of the well bore so that the operator by controlling the drilling string can determine the angle of drilling. The tool of the present invention is sensitive to weight so that the operator by increasing the weight of the drilling string upon the tool can build up angle in a well bore, or by decreasing the weight of the drilling string can allow the tool to drill downwardly or to drop angle. By employing the tool of the present invention a Well bore may be maintained at a given deection after a whipstocking operation without deviating from side to side.

It is also an object of this invention to provide a bore reaming roller bit having both bottom cutters that dig the bore and side reaming cutters that gauge the bore, and

which bit is characterized by the absence of outside leg constructions so that the body of the tool does not come into contact with the well bore.

It is another object of the invention to provide ushing means for the cutters of a bore reaming roller bit of the character referred to, which means acts to clean both the periphery and the outside cutting faces of the roller cutters.

It is still another object of this invention to provide a bore reaming roller bit which acts to open a well bore to full bit diameter and in which the cutters of the bit are of maximum size and are so related to the elements of the structure lthat maximum chip clearance is provided.

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

Figs. l and 2 are cross sectional views taken through a well bore, showing the mode of operation of the roller bit provided by the invention. Fig. 1 shows the bit in operation vto maintain a given angle of deection, while Fig. 2. shows the bit in operation to build angle or to increase the amount of deection. Fig. 3 is an enlarged detailed sectional view`of-the bit that we provide and Mice taken as indicated by line 3-3 on Fig. 5. Fig. 4 is a view taken as indicated by line 4-4 on Fig. 3, showing the structure in cross section. Fig. 5 is an enlarged lower end view of the roller bit taken as indicatedby line 5--5' on Fig. 3 and Fig. 6 is an end view of one of the cutters taken as indicated by line 6-6 on Fig. 3.

The bit T of the present invention is adapted for use at the lower end of a drilling string S which may involve a drill collar 10, a stabilizer 11 and a sub 12. The stabilizer 11 is inserted between the drill collar 10 and sub 12, and the bit T is carried at the lowermost end of the drill string S by the bottom portion of the sub` 12 which is internally threaded at 13 to receive the bit T.

The bore reaming roller bit T provided by this invention acts upon the cylindrical side wall 14'of the bore as well as upon the bottom end 15 thereof and involves, generally, a body A, a pin B projecting upwardly from the body, substantially disc-shaped bore gauging cutters C carried at the sides of the bodyA, roller-type bottom or cross sectional cutters D carried at the bottom of thel body A, anti-friction means rotatably carrying the cutters C, anti-friction means rotatably carrying the cutters D, and flushing means E for cleaning the cutters C and D.

The body A is an elongate vertically disposed element having an outer wall 16, a top face 17 and a depending cutter carrying portion 18. The outer wall 16 is preferably of the same diameter as the drill string'S and extends downwardly from the lower end of the drill string S. The top face 17 faces upwardly and has seating engagement with a lower end face 18' at the bottom end of the sub 12.

The depending cutter carrying portion 18 'of the body A is characterized by and involves a pair of

legs

19 and 20 that extend downwardly from opposite sides of the body, a web 21 that extends between and joins the legs, and a pair of

arms

22 and 23 that also extend downwardly from opposite sides of the body. The parts of the body A are preferably formed of a single body of material and the

legs

19 and 20 project downwardly in substantially diverging planes which are positioned so that the projecting intersecting apex of the planes extend through the vertical axis of the body A while the

arms

22 and 23 projecting downwardly in parallel planes spaced radially of the vertical axis of the body and at right angles to the planes in which the legs occur. The web 21 extends between the

legs

19 and 20 at or near the vertical axis of the structure thereby tying the legs together to prevent spreading and distortion thereof.` The

arms

22 and 23 are also spaced and depend from diametrically opposite sides of the body A. v

The bore gauging cutters C are substantiallyy discshaped members and are on axes which extend trans-- versely of the body A, and are normal to the planes ina which the legs occur. The roller type cutters D are on am axis substantially normal to the axes of the cutters CI and intersect the axes of the

arms

22 and 23 and the vertical axis of the body so that the axes of the cutters C and D are normal to each other in plan view, as illustrated in Fig. 5 of the drawings.

The pin B is in the form of a tapered screw threaded part that projects upwardly from the rface 17 of the body A and has a threaded exterior 24 and a central uid handling bore 25. The exterior 24 is screw threaded into the bottom of the sub 12 at 13, and the bore 25 terminates at a bottom 26 at or within the upper end of the body A.

The bore gauging cutters C are alike and are provided to act upon the cylindrical wall 14 of the well bore as well as upon the peripheral portion of the bottom 15 thereof. Each cutter C is a wheelor disc-shaped element 30 having a side cutting end'portion 31 and a bottom cutting peripheral portion 32. The element 30 has inner'and outer-

peripheral corner edges

33 and 34, and as shown"throughoutvth@drawings; the cutting end vportion 31 has a frusto-conical-face that is confined within the outer peripheral edge 34`of the element 30. The portions 31?: and 32 -offthe cutterse() are formedconcentric with* the central axisofthe cutters Thelcutters" C act upon= the` outer portion` of the Well bore'andtrirn or rearnI the- Wellbore to gauge -asthe earth formation is penetrated; Each cutterC'is-carriedon anY inclinedaxis that extends v`upwardly and outwardlyl from the' body' portion18-andthe central longitudinal axis of theA-tool, so that the-fface'othe side cutting end portion offth'e e1ement'30 liesadjacentto the side 14 vof the'well boreand so that the-bottomcutting*peripheral portion tl1`e-well bore. Inl theV preferredY form of the invention the portions 31 andA 32of the elementlti areso related that 'the frustof-conical cuttingv face of portion 31 conformsto the circular sideV 14 of the well bore, whilethe downwardly disposed tapered portionl 32 is substantially parallel tothe bottom 15 of the well bore.

An annularseries of teeth 35 extend aroundthe circumference of the peripheral portion 32.of the element f'toproject radially-outwardly therefrom. The teeth SSV-may bev-shaped with cutting edges and are preferablyhelically formed and extend between the edges 33 and'34-of lthe element 30. In practice, suitable hardfacing-37 is applied to the-cuttingfedges as is common practice in tools of the type under consideration. The teeth35 may be equally spaced circumferentially of the cutteror'they may be unequally spaced or staggered, as circumstances require.

The Vside cutting portion- 31 ofeach bore gauging cutter Chas a substantially radially disposed, longitudinally outwardly inclined face 33 concentric with the axis of the'cutter. Theface 38 isl coextensive with the outer end offthevr cutter C, and terminates at the outer peripheral edge34thereof. In accordance with the present inven tion,- an7 annular series of borel gauging teeth 39 project axially outwardly fronrtheface` 38 Vofeach cutter C. As clearlyy illustrated in Figs. 3 and 6 of the drawings, the teeth-V 39 are in the form of ridges that` extend radially from the central portionof the cutter to the outer peripl eral portion thereof. In practice, each tooth 39 is in radial alignmentwith one of the teeth 13S-'and is extended radially outwardly to overlie the adjacent end of the tooth 35 Arelated thereto.

Since thefcutters C are establishedv frorn a'single piece of stockand are formed by a forging and/ or machining operation, itwill be apparentthat the adjacent or related teeth- 35and 39 thereof are in fact integrally joined together.

It is preferred that there be a tooth 39 for every other tooth 35, as shown.`

Each ridge-like'tooth 39 has an outer land 40 extendingflongitudinallyv thereof, whichY land is spherically formedfrom a center coincident with they vertical axis of the-bit. In'the-caseA illustratedthe inner end of the land 40of each tooth 39 terminates at a point spaced from the central axis ofthe cutter, while its outerend terminatos-at the' cutting edge'36 of the toothV 3-5 related thereto.-

When the bit of the present invention is operated to penetrate earth formation it is rotated in aclockwise direction as indicated throughout the drawings, in which case the tcutter C revolvesY in a counter-clockwise direction relative to the body A. The teethA 39 are therefore successively brought into cutting engagement'vvith the earth formation. Eachtooth 39 has a'leading cutting edge 42 and a trailing cutting edge 43. which are coextensivey With-the'tooth atthe sidesy ofthe land 4l) so that the :teeth are effective in removing'earth formation from the side-14 ofthe well bore; Suitable hard-facing may bevapplied to. the teeth" 39 as circumstances require. Notches- 457-1 arevprovided in the teeth 39v to allow for 4E chip clearance and in effect establish concentric inner and outer annular serieseof-teethw The bottom or cross sectional cutters D are substantially alike, and are provided to act upon the bottom of the well bore and are characterized by

cylindricallyshaped elements

50 and 50. The elements 50 and 50' are preferably inwardly tapered and have annular sets or series of teeth 52 and 52-"at- Itheir exteriors. As shown, the cutters- Dare-'carried betweenY the legsl 19l and 20 hereinabove referred to, on a common axis which extends horizontally 4between the 'arms 22 .and 23 'and y1101'- mal to the axes of the cuttersl C. It is preferred that the elements 5l) and 50 beof diierentlengths, .so that the element 50 covers the center of the well bore and overlaps the path of the element 50 as the tool operates. The

teeth

52 and 52 are helically pitched in opposite directions and are provided with staggered notches 53 and 53' so that the teeth of one cutter do not track in the path of the -teethof the other cutter.

The means provided forfrotatably carrying the cutters C involve a trunnion 55 for each element 30. The trunnions- 55 project upwardly and outwardly from the outer sides 56-1ofy the-divergentlegs-19 and 20, respec` tively, and each trunnionhas aL radial bearing'surface 57 vrand an annular race 48-at the outer terminal end thereof. Each cutter elementhas a bore 59'thatis adapted to receive a trunnion 55- and which has an inner bearing surface 6l) -and an lannular racel 61 -at the-outer end thereof. An annular row or series of anti-friction4 rollers 62, or thellike,-gis'provided between the bearing surfaces 57 and 60, land the rollers areretained by axially spaced shoulders inthe member 30;

The cutters C are retained on the trunnions 551by means of an annunlar seriesof balls 63 operatingV in the races 4S f and 61. As shown, the race @lis formed inthe bore59 to open radially inwardly while the race Sie formed in the trunnion 55to open longitudinally and radially outwardly. in practice, a retainer`64 is threadedlyl secured to they end portionA ofthe trunnion 55at S5-and, as shown, forms the outer half ofthe race 4S. A suitable lock pin, or kthe like, may be provided to secure the retainer in position. lt will be apparent how the balls 63l are inserted between the races and retained therein to take axial thrust thereby-rotatably securing the cutter on the trumn'on.. As Vshown in Fig. 3 of the drawings,` a'cover plate 66 is provided and closes the outer end of the bore 59 covering the'bearing rollers 62'and`balls 63 and the retainer 64; Welding,` or 'the like, isused to fasten the plate 66 in place.

The means for rotatably carrying the cutters D involves a pin 7S and bearing supports for the pin. The pin 75 is a simple elongate part that extends trans-y versely of the bottom of the body A ,between the .

arms

22 and 23. caring openings 75and 77`are provided inthe arms at-the sides of the body A and a bearing opening 78 is providedn the web 21between the ele-v ments 50 and 50'. As shown, in Fig. 4 of the drawings, the web 21 is off-set relative to the central axis of the body A, and the bearing openings 76, 77 and 78'are aligned in the

arms

22 and 23 .and web 21 for receiving and carrying the pin 75. The pin 75 has anouter bearing surface 82, while the

elements

50 and 50 have inner bearing surfaces 83 and S3'. An annular row of rollers 84 is provided between the bearing lsurfacesof each'cutter and the pin, so that the cutters are free to rotate on the pin. The pin 75 may be suitably secured inthe bearing openings in the arms and web of the body A by means of welding, or the like.

The flushing means provided by the present invention provides for cleaning. of both sets ofy rollers. That is, the flushing means acts. to flush or clean the bore gauging cutters Cjas well as the bottom vor cross sectional cutter D. As clearly illustrated in Figs. 3 and 4 of the drawings, jets. are provided whichv direct ythe ow of mud from the dri11ing ,string.,to.the, edge;` 34 ofcach.v

cutter element 30. It will be noted that the streams of mud delivered by the jets 90 are split by the edges 34, so that a portion of the mud cleans the end faces 38 of the cutters while a portion of the mud cleans the periphery thereof. I ets 91 carry mud to the lower cross sectional cutters D as shown in Fig. 4 of the drawings.

In operation of the bit, the shank or pin is connected with the lower end of the drilling string and the bit is operated on the lower end of the string in the usual manner. As the bit i-s fed downwardly the cross section cutters D act on and cut away the formation in the central portion of the bottom 15 of the bore while the bore gauging cutters C act on and cut away the formation at the outer portion of the bottom 15 and cut the wall 14 of the bore to gauge. The cutters are positioned so that they have direct active cutting engagement with the entire bottom of the well bore, as the tool or bit revolves, there being no outer legs or supports as employed in usual bit constructions. The circulation uid or mud is pumped downwardly through the drilling string and discharges through the

jets

90 and 91 to clear the chips from the cutters and from the bottom and sides of the well bore.

In order to build angle in a deected well bore as clearly illustrated in Fig. 2 of the drawings, a substantial amount of weight is applied to the bit through the drill string as indicated by the arrow X. The drill string is then rotated whereupon the cutters C act to cut upon the high side of the well bore as indicated by the arrow Z', there being no outer legs or supports to prevent such action as is the case with ordinary bit constructions.

In order to drop angle or to return a well bore to vertical, as clearly illustrated in Fig. 1 of the drawings, it is merely necessary to use less weight of the drilling string in the direction indicated by the arrow X and to rotate the string so that the cutters C act upon the lower yside of the well bore as indicated by the arrow Z, there being no interference from body parts such as legs or supports.

Having described only typical preferred tforms and applications of our invention, We do not Wish to be limited or restricted to the specific details herein set forth, but wish to reserve to ourselves any variations or modifications that may appear to those skilled in the art and fall within the scope of the following claims:

Having described our invention, we claim:

l. A well boring bit of the character referred to including, an elongate vertically disposed cylindrical body, a pair of downwardly divergent legs depending from diametrically opposite sides of the body, a pair of arms depending from diametrically opposing sides of the body and spaced 90 from the legs, a pair of axially aligned elongate, horizontally disposed roller cutters of different longitudinal extent extending between and rotatably carried by the arms to occur between the lower end portions of the legs and engage the bottom of a well bore, a substantially disc-shaped cutter with a substantially radially outwardly facing frusto-conical end rotatably carried by each leg to project outwardly therefrom on an axis disposed radially outwardly and upwardly relative to the central vertical axis of the body, each disc-shaped cutter having circumferentially spaced axially disposed cutting teeth about its outer periphery to engage the bottom of the well bore and having outwardly projecting radially disposed bore engaging teeth on said frusto-conical end to engage the bore, said bore engaging teeth being in radial alignment with and joining the bottom engaging teeth related thereto, said bore engaging teeth being spherically curved about a common point occurring on the central vertical axis of the bit and ushing means for each discshaped cutter including a uid handling bore in the body and a jet opening in the body related to each of said cutters and adapted to direct circulating uid on the cutters between the axially and radially disposed teeth thereon.

2. A well boring bit of the character referred to including, an elongate vertically disposed body, a pair of downwardly divergent legs depending from diametrically opposite sides of the body, a pair of arms depending from diametrically opposite sides of the body and spaced from the legs, a web extending between the legs and offset from the vertical axis of the body, an elongate horizontally disposed shaft extending between and carried by the arms to intersect the vertical axis of the body, project through the web and occur between the lower end portions of the legs, an elongate roller cutter rotatably carried by the shaft between the web and each arm and adapted to engage the bottom of a well bore, a substantially disc-shaped cutter with a radially outwardly facing frusto-conical end rotatably carried by each leg to project radially outwardly therefrom on a radially outwardly and upwardly inclined axis and having circumferentially spaced axially disposed cutting teeth about its periphery to engage the bottom of the well bore and having outwardly projecting, radially disposed bore engaging teeth on said frusto-conical end to engage the wall of the bore, said bore engaging teeth being arranged in radial alignment with the axially disposed teeth and extending radially outwardly from said edge of the cutter to join with the adjacent ends of the axially disposed teeth related thereto, said radially disposed teeth being spherically curved about a common point occurring on the central vertical axis of the bit, and ushing means for each cutter including a fluid handling bore in the body and jet openings in the lower end of the body related to each cutter.

3. A well boring bit of the character referred to including, an elongate vertically disposed body, a pair of downwardly divergent legs depending from diametrically opposite sides of the body, a pair of arms depending from diametrically opposite sides of the body and4k spaced 90 from the lower end portion of the legs, a web extending between the legs and offset from the vertical axis of the body, an elongate horizontally disposed shaft extending between and carried by the arms to intersect the vertical axis of the body, project through the web and occur between the lower end portions of the legs, an elongate roller cutter rotatably carried by the shaft between the web and each arm and adapted to engage the bottom of a well bore, a substantially disc-shaped cutter with a radially outwardly facing frusto-conical end rotatably carried by each leg to project radially outwardly therefrom on a radially outwardly and upwardly inclined axis and having axially disposed cutting teeth about its periphery to engage the bottom of the well bore and having outwardly projecting, radially disposed bore engaging teeth on said irusto-conical end to engage the wall of the bore, said bore engaging teeth being arranged in radial alignment with the axially disposed teeth and extending radially outwardly from said edge of the cutter to join with the adjacent ends of the axially disposed teeth related thereto, said radially disposed teeth being spherically curved about a common point occurring on the central vertical axis of the bit, and flushing means for each cutter including a uid handling bore in the body and jet openings in the lower end of the body related to each cutter, said jet openings related to the roller cutter being directed towards the top of each roller cutter at a point intermediate its ends, said jet opening related to each disc-shaped cutter being directed at the top of each disc-shaped cutter at a point where said frusto-conical end joins the outer periphery of the cutter.

References Cited in the le of this patent UNITED STATES PATENTS 1,195,208 Griin Aug. 22, 1916 1,284,453 Reed Nov. 12, 1918 1,327,913 Hughes Ian. 13, 1920 2,058,626 Reed Oct. 27, 1936 2,634,955 Johnson Apr. 14, 1953