US3720274A - Earth boring bit thrust bearing - Google Patents

Earth boring bit thrust bearing Download PDF

Info

Publication number
US3720274A
US3720274A US00145651A US3720274DA US3720274A US 3720274 A US3720274 A US 3720274A US 00145651 A US00145651 A US 00145651A US 3720274D A US3720274D A US 3720274DA US 3720274 A US3720274 A US 3720274A
Authority
US
United States
Prior art keywords
bearing pin
diameter
thrust
thrust surface
cutter member
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00145651A
Inventor
Callum H Mc
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dresser Industries Inc
Original Assignee
Dresser Industries Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dresser Industries Inc filed Critical Dresser Industries Inc
Application granted granted Critical
Publication of US3720274A publication Critical patent/US3720274A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C21/00—Combinations of sliding-contact bearings with ball or roller bearings, for exclusively rotary movement
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B10/00—Drill bits
    • E21B10/08—Roller bits
    • E21B10/22—Roller bits characterised by bearing, lubrication or sealing details
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B10/00—Drill bits
    • E21B10/08—Roller bits
    • E21B10/22—Roller bits characterised by bearing, lubrication or sealing details
    • E21B10/23—Roller bits characterised by bearing, lubrication or sealing details with drilling fluid supply to the bearings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C2352/00—Apparatus for drilling

Definitions

  • the present invention relates to the art of earth boring and more particularly to a rolling cone rock bit.
  • the present invention is especially adapted for use on that type of rock bit popularly known as a three-cone bit; however, its use is not restricted thereto and the present invention can be used in other types of rotary rock bits.
  • a three-cone rotary rock bit is adapted to be connected as a lower member of a rotary drill string. As the drill string is rotated, the bit disintegrates the formations to form an earth borehole.
  • the three-cone rotary rock bit includes three individual arms that extend angularly downward from the main body of the bit. The lower end of each arm is shapedto form a spindle or hearing pin.
  • a cone cutter is mounted upon each bearing pin and adapted to rotate thereon. Individual bearing systems promote rotation of the cone cutter. These bearing systems have traditionally been roller bearings, ball bearings, friction bearings or a combination of the aforementioned bearings.
  • the cone cutters include cutting structure on their outer surfaces that serve to disintegrate the formation as the bit is rotated.
  • the bit is subjected to a thrust load during operation.
  • the weight of the drill string and the downward force applied by the rotary drill equipment apply a substantial thrust load upon the earth boring bit.
  • this thrust load was taken by a thrust button in the nose of the cone cutter which rotated against a hard faced surface on the inner end of the bearing pin and by the ball bearing system of the earth boring bit.
  • Prior art earth boring bits have experienced early failure because of their inability to support the extensive thrust loading.
  • the thrust button and ball bearing systems have been unable to adequately support the thrust loads under certain drilling conditions and excessive wear of the elements subjected to the thrust forces has resulted in the cone cutters becoming disoriented with respect to the bearing pins with a consequent early failure of the bit.
  • Certain earth boring bits used in the mining industry and popularly called blast or shothole bits have been constructed with an outer roller bearing system and an inner ball bearing system.
  • the usual inner bearing system generally a roller bearing or friction hearing, has been omitted.
  • the space left by the omission of the inner bearing system has created a problem in that on occasion the cone cutter becomes disoriented with respect to the bearing pin resulting in early failure of the bit.
  • the innermost part of the bearing cavity formed in the cutter includes a thrust button which bears against the lowermost end of the bearing pin to absorb thrust forces.
  • the ball bearing system of this bit also aids in absorbing the thrust forces.
  • Another earth boring bit shown in this patent discloses an earth boring bit with a friction, ball-friction bearing system.
  • the present invention provides an improved bearing system for a rolling cone earth boring bit that will support thrust loads and prevent the cone cutters from becoming disoriented on the bearing pins.
  • the present invention stabilizes the cone cutters, increases bearing life, reduces heat generation, provides an intermediate thrust element between the bearing pin and the interior of the cutter shell thereby providing a material that may be more compatible with the metals that are used for the bearing pin and the cutter shell and in general provides an improved earth boring bit.
  • the intermediate thrust element is located between a thrust surface on the bearing pin and a thrust surface on the associated cone cutter.
  • the intermediate thrust element is generally not affixed to the bearing pin or the cutter shellbut is allowed to float freely between the bearing pin and the cutter shell.
  • FIG. 1 illustrates an earth boring bit of the prior art.
  • FIG. 2 is a sectional view of one arm of an earth boring bit of the present invention.
  • FIG. 3 is an enlarged view of a portion of the bit shown in FIG. 2.
  • FIG. 4 illustrates one embodiment of intermediate thrust element of the present invention.
  • H6. 5 illustrates diagrammatically some of the forces imposed upon the elements of an earth boring bit during drilling.
  • FIG. 6 illustrates another embodiment of an intermediate thrust element of the present invention.
  • FIG. 1 an earth boring bit of the prior art is shown and designated generally by the reference number 10.
  • the bit 10 includes a body portion 12 having an upper portion 14 that is threaded to allow bit to be connected to a rotary drill string (not shown).
  • a multiplicity of arms 16, 16, etc. extend from body portion 12.
  • the lower portion of each arm 16, 16', etc. forms a bearing pin 18 that projects into a recess 20 formed in the associated rotary cutter 22.
  • the cutter 22 is journaled on bearing pin 18 by roller bearings 24, ball bearings 26 and thrust button 28.
  • a passage system 30 provides conduits to transport cooling fluid to the bearings.
  • the prior art earth boring bit 10 supports the entire thrust load with the ball bearings 26 and the thrust button 28.
  • the bit 10 tends to become unstable and an increased load is placed upon the roller bearings 26.
  • the cone cutter 22 tends to become cocked with respect to the bearing pin 18 since cutter 22 wants to pivot about thrust button 28.
  • the bit 10 consequently experiences early failure.
  • certain of the prior art bits are constructed without the usual inner bearing system.
  • the inner friction bearing system may be deleted in the roller-ball-friction type bits.
  • the space left by the deletion of this bearing system aggravates the stabilization problem previously discussed.
  • the space 34 in the prior art bit 10 is an example of this type of construction.
  • FIG. 2 A single arm 36 of an earth boring bit constructed in accordance with the teachings of the present invention is shown in FIG. 2.
  • the lower portion of arm 36 forms a bearing pin 38.
  • the bearing pin 38 projects into a recess 40 formed in cutter 42.
  • the cutter 42 is journaled on hearing pin 38 by roller bearing 44, ball bearings 46 and thrust button 48.
  • a passage system 50 provides conduits to transport cooling fluid to the bearings.
  • the cutter 42 includes a number of inserts 52 projecting from its outer surface that serve to disintegrate the formations during drilling.
  • An intermediate element 54 is positioned in recess 50 between a thrust surface 56 on bearing pin 38 and a thrust surface 58 on cutter 42.
  • the thrust element 54 is not affixed to the bearing pin 38 or the cutter 42 but is allowed to float freely around bearing pin 38.
  • FIG. 3 an enlarged view of the intermediate element 54, bearing pin 38 and cutter 42 taken from area 3 of FIG. 2 is shown.
  • the intermediate element 54 forms an annular ring that completely encircles the bearing pin 38.
  • the central opening 60 of intermediate element 54 is of sufficient size that it does not restrict the cooling fluid emerging from passage system 50.
  • a thrust surface 62 on intermediate element 54 bears against thrust surface 56 on bearing pin 38 and a thrust surface 64 bears against thrust surface 58 on cutter 42.
  • the intermediate element 54 is free to rotate with cutter 42, remain relatively stationary with hearing pin 38 or rotate independently.
  • FIG. 4 A top view of intermediate element 54 is shown in FIG, 4.
  • the intermediate element 54 is constructed from a material that is compatible with the bearing pin material and the cutter material.
  • the intermediate element 54 is constructed of A.S.T.M.; B148, alloy 9C.
  • the intermediate element 54 improves the performance of the bit and increases its lifetime.
  • the intermediate element 54 helps support the thrust load, aids stabilizing of the bit, reduces heat generation thereby allowing the hearings to run cooler and provides a material that may be more compatible with the bearing pin and cutter materials.
  • the thrust load consists of a horizontal component 66 and a vertical component 68. This load 66 and 68 must be transmitted from the cutter 72 to the bearing pin 74. Earth boring bits of the prior art would support the thrust load almost entirely by the thrust button 76 and the ball bearing system 78. THus the components 66 and 68 would be transmitted to bit as components 80, 82, 84 and 86.
  • the bearing system 78 would tend to wear and enlarge ball race 88. As this happened, the cutter 72 would become disoriented on hearing pin 74 and an increasingly larger load component placed upon the roller bearing system 92. The increased load 90 would produce an early failure of the roller bearing system 92 and a consequent early failure of the bit.
  • intermediate element 94 between a thrust surface 96 on hearing pin 74 and a thrust surface 98 on cutter 72 helps support the thrust load, stabilizes cutter 72 and promotes rotation of cutter 72.
  • Intermediate element 94 receives a portion of the thrust load as illustrated by components 100 and 102. This helps prevent cutter 72 from becoming disoriented upon bearing pin 74 thereby reducing the load component 90 acting against the roller bearing system 92.
  • the intermediate element 94 may be left to float freely between cutter 72 and bearing pin 74 with the relative rotational speeds between intermediate element 94 and the surfaces 96 and 98 being less than if surfaces 96 and 98 were running directly against each other.
  • intermediate element 94 may be constructed of a material that has greater friction bearing compatibility with the bearing pin material and the cutter material than they would have with each other.
  • the intermediate element 54 is constructed of materials that provide the surfaces 62 and 64 with anti-galling properties.
  • the entire intermediate element may be constructed of the material having antigalling properties or only the outer portion of the intermediate element may include the materials having these properties.
  • the anti-galling materials may cover the entire surface or the anti-galling materials may be interspersed with other materials.
  • the intermediate element may be constructed of materials that provide its outer surfaces with hard wear resistant properties.
  • the intermediate element 94 shown in FIG. 5 may be constructed of A.I.S.I. 440C Stainless Steel.
  • the hard wear resistant materials may cover the entire surface or the wear resistant materials may be interspersed with other materials.
  • the intermediate element 104 shown in FIG. 5 consists of two semi-circular sections 106 and 108.
  • the surfaces 110 and 112 of sections 106 and 108 must be compatible with the materials of the bearing pin and cutter that they run against.
  • Sections 106 and 108 may be constructed of a hard wear resistant material selected from the group consisting of hardened steel, hardened aluminum bronze and tungsten carbide.
  • sections 106 and 108 may be constructed of an anti-galling material selected from the group consisting of copperbased alloys, silver babbitt metal, aluminum and zinc.
  • the entire intermediate element being constructed of one of the materials mentioned above, the
  • intermediate element may be a mixture of the materials; a material may be plated on the outer surface of the intermediate element or the surface may be given the above-mentioned properties by other process.
  • the intermediate element may have surface grooves filled with an anti-galling material or the intermediate element may be a laminated polytetrafluoroethylene fiber washer.
  • An earth boring bit comprising:
  • a bit body having an upper end eonnectable with a rotary drill string; at least one bearing pin extending from said bit body, said bearing pin having a first portion with a first diameter, a second portion with a second diame ter, said second diameter being smaller than said first diameter, and a bearing pin thrust surface between said first portion and said second portion;
  • a cutter member rotatably positioned on said bearing pin, said cutter member having a first inner portion with a diameter larger than said bearing pin first diameter and a second inner portion with a diameter smaller than said bearing pin first diameter but larger than said bearing pin second diameter, with a cutter member thrust surface on the inner portion of said cutter member between said first inner portion and said second inner portion;
  • an intermediate element positioned between said bearing pin thrust surface and said cutter member thrust surface, said intermediate element having a first thrust surface opposite said bearing pin thrust surface and a second thrust surface opposite said cutter member thrust surface.
  • first and second thrust surfaces of said intermediate element have areas with wear resistant characteristics and areas with anti-galling characteristics.
  • inter mediate element includes materials with wear resistant characteristics and materials with anti-galling characteristics.
  • inter mediate thrust element is constructed from a material selected from the group consisting of hardened steel, hardened aluminum bronze and tungsten carbide.
  • intermediate thrust element is constructed from a material selected from the group consisting of carburized stainless steel, hardened alloy steel and hardened tool steel.
  • intermediate thrust element is' constructed from a material selected from the group consisting of copper-based alloys, silver, babbitt metal, aluminum and zinc.

Landscapes

  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • General Engineering & Computer Science (AREA)
  • Earth Drilling (AREA)

Abstract

Intermediate thrust elements are positioned between the cutters and the bearing pins of an earth boring bit. Each intermediate thrust element is located between a thrust surface on a bearing pin and a thrust surface on the associated cutter. The intermediate thrust elements aid stabilization of the rotating cutter, promote cutter rotation and extend the lifetime of the bit.

Description

1 1March 13, 1973 United States Patent 1 1 McCallum ....308/8.2 ....308/8.2 Schlumpfet .....308/8 2 54] EARTH BORING BIT THRUST 3,656,764 4 1972 Robinson.........................
BEARING 2,444,724 7 1943 Brown 2,065,742 12/1936 Reed [75] Inventor: Hugh F. McCallum, H1bb1ng, Mmn. 2,075,999 4/1937 Reed [73] Assigneez 2,104,819 1/1938 [22] Filed:
Dresser Industries, Inc., Dallas, Tex.
May 21, 1971 Primary Examiner-David H. Brown Attorney-Robert W. Mayer, Thomas P. Hubbard, Jr., Daniel Rubin, Raymond T. Majesko, Roy L. Van Winkle, William E. Johnson, Jr. and Eddie E. Scott [211 App]. No.: 145,651
T C A R T S B A n 5 2 0 H 89 0-D 31 92 2E 7" 3 u 5 7 1 u QML Um NH 55 [l [58] Field of Search 372; 308/82 Intermediate thrust elements are positioned between the cutters and the bearing pins of an earth boring bit. References Cited Each intermediate thrust element is located between 21 UNITED STATES PATENTS thrust surface on a bearing pin and a thrust surface on the associated cutter. The intermediate thrust ele- 6 t 0 m m 1. ub 6 e a 5 uf co m 2.6 mm .E
41 F a MK n l .1 e W mr t r. elm D 0 6 m s, e m 8 0 a Zn 1 m 0 b 9 mm XXX. 222 777W 333 ///3 555 777 4 mfl dn 3 RFH 609 356 999 111 Ill 07 l 1 44 6 2345 6 6 3 4 0030 s ooo 0 5 4 6 2233 PATENTEBHAR 1 3197s SHEET 1 or 2 FIG. I
PRIOR ART FIG. 3
INVENTOR HUGH F. McCALLUM ATTORNEY Pmmmmm 3,720,274
sum 2 or 2 FIG. 4
FIG. 5
HO I06 FIG. 6
, INVENTOR HUGH F. MCCALLUM EARTH BORING BIT TIIRUST BEARING BACKGROUND OF THE INVENTION The present invention relates to the art of earth boring and more particularly to a rolling cone rock bit. The present invention is especially adapted for use on that type of rock bit popularly known as a three-cone bit; however, its use is not restricted thereto and the present invention can be used in other types of rotary rock bits.
A three-cone rotary rock bit is adapted to be connected as a lower member of a rotary drill string. As the drill string is rotated, the bit disintegrates the formations to form an earth borehole. The three-cone rotary rock bit includes three individual arms that extend angularly downward from the main body of the bit. The lower end of each arm is shapedto form a spindle or hearing pin. A cone cutter is mounted upon each bearing pin and adapted to rotate thereon. Individual bearing systems promote rotation of the cone cutter. These bearing systems have traditionally been roller bearings, ball bearings, friction bearings or a combination of the aforementioned bearings. The cone cutters include cutting structure on their outer surfaces that serve to disintegrate the formation as the bit is rotated.
In addition tothe rotationalforces, the bit is subjected to a thrust load during operation. The weight of the drill string and the downward force applied by the rotary drill equipment apply a substantial thrust load upon the earth boring bit. In prior art earth boring bits, this thrust load was taken by a thrust button in the nose of the cone cutter which rotated against a hard faced surface on the inner end of the bearing pin and by the ball bearing system of the earth boring bit.
Prior art earth boring bits have experienced early failure because of their inability to support the extensive thrust loading. The thrust button and ball bearing systems have been unable to adequately support the thrust loads under certain drilling conditions and excessive wear of the elements subjected to the thrust forces has resulted in the cone cutters becoming disoriented with respect to the bearing pins with a consequent early failure of the bit. Certain earth boring bits used in the mining industry and popularly called blast or shothole bits have been constructed with an outer roller bearing system and an inner ball bearing system. The usual inner bearing system, generally a roller bearing or friction hearing, has been omitted. The space left by the omission of the inner bearing system has created a problem in that on occasion the cone cutter becomes disoriented with respect to the bearing pin resulting in early failure of the bit.
DESCRIPTION OF THE PRIOR ART ball-friction bearing system. The innermost part of the bearing cavity formed in the cutter includes a thrust button which bears against the lowermost end of the bearing pin to absorb thrust forces. The ball bearing system of this bit also aids in absorbing the thrust forces. Another earth boring bit shown in this patent discloses an earth boring bit with a friction, ball-friction bearing system.
SUMMARY OF THE INVENTION The present invention provides an improved bearing system for a rolling cone earth boring bit that will support thrust loads and prevent the cone cutters from becoming disoriented on the bearing pins. The present invention stabilizes the cone cutters, increases bearing life, reduces heat generation, provides an intermediate thrust element between the bearing pin and the interior of the cutter shell thereby providing a material that may be more compatible with the metals that are used for the bearing pin and the cutter shell and in general provides an improved earth boring bit. The intermediate thrust element is located between a thrust surface on the bearing pin and a thrust surface on the associated cone cutter. The intermediate thrust element is generally not affixed to the bearing pin or the cutter shellbut is allowed to float freely between the bearing pin and the cutter shell.
It is therefore an object of the present invention to provide an improved rolling coneearth boring bit.
It is a further object ofthe present invention to provide a rolling cone earth boring bit that will support thrust loads better than bits of the prior art.
It is a still further object of the present invention to provide better stabilization of the cutters of an earth boring bit.
It is a still further object of the present invention to provide an intermediate element between the bearing pins and the cutters of an earth boring bit.
The above and other objects and advantages of the present invention will become apparent from a consideration of the following detailed description of the invention when taken in conjunction with the drawing.
BRIEF DESCRIPTION OF TI-IE DRAWING FIG. 1 illustrates an earth boring bit of the prior art.
FIG. 2 is a sectional view of one arm of an earth boring bit of the present invention.
FIG. 3 is an enlarged view of a portion of the bit shown in FIG. 2.
FIG. 4 illustrates one embodiment of intermediate thrust element of the present invention.
H6. 5 illustrates diagrammatically some of the forces imposed upon the elements of an earth boring bit during drilling.
FIG. 6 illustrates another embodiment of an intermediate thrust element of the present invention.
DETAILED DESCRIPTION OF THE INVENTION Referring now to FIG. 1 an earth boring bit of the prior art is shown and designated generally by the reference number 10. The bit 10 includes a body portion 12 having an upper portion 14 that is threaded to allow bit to be connected to a rotary drill string (not shown). A multiplicity of arms 16, 16, etc., extend from body portion 12. The lower portion of each arm 16, 16', etc., forms a bearing pin 18 that projects into a recess 20 formed in the associated rotary cutter 22. The cutter 22 is journaled on bearing pin 18 by roller bearings 24, ball bearings 26 and thrust button 28. A passage system 30 provides conduits to transport cooling fluid to the bearings.
The prior art earth boring bit 10 supports the entire thrust load with the ball bearings 26 and the thrust button 28. As the ball race 32 wears, the bit 10 tends to become unstable and an increased load is placed upon the roller bearings 26. The cone cutter 22 tends to become cocked with respect to the bearing pin 18 since cutter 22 wants to pivot about thrust button 28. The bit 10 consequently experiences early failure.
In addition, certain of the prior art bits are constructed without the usual inner bearing system. For example, the inner friction bearing system may be deleted in the roller-ball-friction type bits. The space left by the deletion of this bearing system aggravates the stabilization problem previously discussed. The space 34 in the prior art bit 10 is an example of this type of construction.
A single arm 36 of an earth boring bit constructed in accordance with the teachings of the present invention is shown in FIG. 2. The lower portion of arm 36 forms a bearing pin 38. The bearing pin 38 projects into a recess 40 formed in cutter 42. The cutter 42 is journaled on hearing pin 38 by roller bearing 44, ball bearings 46 and thrust button 48. A passage system 50 provides conduits to transport cooling fluid to the bearings. The cutter 42 includes a number of inserts 52 projecting from its outer surface that serve to disintegrate the formations during drilling. An intermediate element 54 is positioned in recess 50 between a thrust surface 56 on bearing pin 38 and a thrust surface 58 on cutter 42. The thrust element 54 is not affixed to the bearing pin 38 or the cutter 42 but is allowed to float freely around bearing pin 38.
Referring now to FIG. 3 an enlarged view of the intermediate element 54, bearing pin 38 and cutter 42 taken from area 3 of FIG. 2 is shown. The intermediate element 54 forms an annular ring that completely encircles the bearing pin 38. The central opening 60 of intermediate element 54 is of sufficient size that it does not restrict the cooling fluid emerging from passage system 50. A thrust surface 62 on intermediate element 54 bears against thrust surface 56 on bearing pin 38 and a thrust surface 64 bears against thrust surface 58 on cutter 42. The intermediate element 54 is free to rotate with cutter 42, remain relatively stationary with hearing pin 38 or rotate independently.
A top view of intermediate element 54 is shown in FIG, 4. The intermediate element 54 is constructed from a material that is compatible with the bearing pin material and the cutter material. In this embodiment, the intermediate element 54 is constructed of A.S.T.M.; B148, alloy 9C. The intermediate element 54 improves the performance of the bit and increases its lifetime. The intermediate element 54 helps support the thrust load, aids stabilizing of the bit, reduces heat generation thereby allowing the hearings to run cooler and provides a material that may be more compatible with the bearing pin and cutter materials.
In addition to the rotary forces applied to a bit during drilling, a substantial thrust load is imposed upon the bit. The bit must support both the weight of the drill string and the load applied to the drill string by the rotary equipment. The more important components of the thrust load and their effect on the bit are illustrated in FIG. 5. The thrust load consists of a horizontal component 66 and a vertical component 68. This load 66 and 68 must be transmitted from the cutter 72 to the bearing pin 74. Earth boring bits of the prior art would support the thrust load almost entirely by the thrust button 76 and the ball bearing system 78. THus the components 66 and 68 would be transmitted to bit as components 80, 82, 84 and 86. However, as the drilling operation proceeded, the bearing system 78 would tend to wear and enlarge ball race 88. As this happened, the cutter 72 would become disoriented on hearing pin 74 and an increasingly larger load component placed upon the roller bearing system 92. The increased load 90 would produce an early failure of the roller bearing system 92 and a consequent early failure of the bit.
The provision of an intermediate element 94 between a thrust surface 96 on hearing pin 74 and a thrust surface 98 on cutter 72 helps support the thrust load, stabilizes cutter 72 and promotes rotation of cutter 72. Intermediate element 94 receives a portion of the thrust load as illustrated by components 100 and 102. This helps prevent cutter 72 from becoming disoriented upon bearing pin 74 thereby reducing the load component 90 acting against the roller bearing system 92. The intermediate element 94 may be left to float freely between cutter 72 and bearing pin 74 with the relative rotational speeds between intermediate element 94 and the surfaces 96 and 98 being less than if surfaces 96 and 98 were running directly against each other. In addition, intermediate element 94 may be constructed of a material that has greater friction bearing compatibility with the bearing pin material and the cutter material than they would have with each other.
In the embodiment of the invention shown in FIGS. 3', 4 and 5, the intermediate element 54 is constructed of materials that provide the surfaces 62 and 64 with anti-galling properties. The entire intermediate element may be constructed of the material having antigalling properties or only the outer portion of the intermediate element may include the materials having these properties. The anti-galling materials may cover the entire surface or the anti-galling materials may be interspersed with other materials. In other embodiments of the invention, the intermediate element may be constructed of materials that provide its outer surfaces with hard wear resistant properties. For example, the intermediate element 94 shown in FIG. 5 may be constructed of A.I.S.I. 440C Stainless Steel. The hard wear resistant materials may cover the entire surface or the wear resistant materials may be interspersed with other materials. In the preferred embodiment of the invention the intermediate element has been shown as an annular ring; however, other shapes and forms of the intermediate element are contemplated. The intermediate element 104 shown in FIG. 5 consists of two semi-circular sections 106 and 108. The surfaces 110 and 112 of sections 106 and 108 must be compatible with the materials of the bearing pin and cutter that they run against. Sections 106 and 108 may be constructed of a hard wear resistant material selected from the group consisting of hardened steel, hardened aluminum bronze and tungsten carbide. Alternatively, sections 106 and 108 may be constructed of an anti-galling material selected from the group consisting of copperbased alloys, silver babbitt metal, aluminum and zinc. Instead of the entire intermediate element being constructed of one of the materials mentioned above, the
intermediate element may be a mixture of the materials; a material may be plated on the outer surface of the intermediate element or the surface may be given the above-mentioned properties by other process. For example, the intermediate element may have surface grooves filled with an anti-galling material or the intermediate element may be a laminated polytetrafluoroethylene fiber washer.
The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:
1. An earth boring bit, comprising:
a bit body having an upper end eonnectable with a rotary drill string; at least one bearing pin extending from said bit body, said bearing pin having a first portion with a first diameter, a second portion with a second diame ter, said second diameter being smaller than said first diameter, and a bearing pin thrust surface between said first portion and said second portion;
a cutter member rotatably positioned on said bearing pin, said cutter member having a first inner portion with a diameter larger than said bearing pin first diameter and a second inner portion with a diameter smaller than said bearing pin first diameter but larger than said bearing pin second diameter, with a cutter member thrust surface on the inner portion of said cutter member between said first inner portion and said second inner portion;
bearing means between said bearing pin and said cutter member for promoting rotation of said cutter member; and
an intermediate element positioned between said bearing pin thrust surface and said cutter member thrust surface, said intermediate element having a first thrust surface opposite said bearing pin thrust surface and a second thrust surface opposite said cutter member thrust surface.
2. The earth boring bit of claim 1 wherein the first and second thrust surfaces of said intermediate element have wear resistant characteristics.
3. The earth boring bit of claim 1 wherein the first and second thrust surfaces of said intermediate element have anti-galling characteristics.
4. The earth boring bit of claim 1 wherein the first and second thrust surfaces of said intermediate element have areas with wear resistant characteristics and areas with anti-galling characteristics.
5. The earth boring bit of claim 1 wherein said intermediate element is constructed from a material having anti-galling characteristics.
6. The earth boring bit of claim 1 wherein said inter mediate element includes materials with wear resistant characteristics and materials with anti-galling characteristics.
7. The earth boring bit of claim 1 wherein the inter mediate thrust element is constructed from a material selected from the group consisting of hardened steel, hardened aluminum bronze and tungsten carbide.
8. The earth boring bit of claim 1 wherein the intermediate thrust element is constructed from a material selected from the group consisting of carburized stainless steel, hardened alloy steel and hardened tool steel.
9. The earth boring bit of claim 1 wherein the intermediate thrust element is' constructed from a material selected from the group consisting of copper-based alloys, silver, babbitt metal, aluminum and zinc.
* II i i

Claims (9)

1. An earth boring bit, comprising: a bit body having an upper end connectable with a rotary drill string; at least one bearing pin extending from said bit body, said bearing pin having a first portion with a first diameter, a second portion with a second diameter, said second diameter being smaller than said first diameter, and a bearing pin thrust surface between said first portion and said second portion; a Cutter member rotatably positioned on said bearing pin, said cutter member having a first inner portion with a diameter larger than said bearing pin first diameter and a second inner portion with a diameter smaller than said bearing pin first diameter but larger than said bearing pin second diameter, with a cutter member thrust surface on the inner portion of said cutter member between said first inner portion and said second inner portion; bearing means between said bearing pin and said cutter member for promoting rotation of said cutter member; and an intermediate element positioned between said bearing pin thrust surface and said cutter member thrust surface, said intermediate element having a first thrust surface opposite said bearing pin thrust surface and a second thrust surface opposite said cutter member thrust surface.
1. An earth boring bit, comprising: a bit body having an upper end connectable with a rotary drill string; at least one bearing pin extending from said bit body, said bearing pin having a first portion with a first diameter, a second portion with a second diameter, said second diameter being smaller than said first diameter, and a bearing pin thrust surface between said first portion and said second portion; a Cutter member rotatably positioned on said bearing pin, said cutter member having a first inner portion with a diameter larger than said bearing pin first diameter and a second inner portion with a diameter smaller than said bearing pin first diameter but larger than said bearing pin second diameter, with a cutter member thrust surface on the inner portion of said cutter member between said first inner portion and said second inner portion; bearing means between said bearing pin and said cutter member for promoting rotation of said cutter member; and an intermediate element positioned between said bearing pin thrust surface and said cutter member thrust surface, said intermediate element having a first thrust surface opposite said bearing pin thrust surface and a second thrust surface opposite said cutter member thrust surface.
2. The earth boring bit of claim 1 wherein the first and second thrust surfaces of said intermediate element have wear resistant characteristics.
3. The earth boring bit of claim 1 wherein the first and second thrust surfaces of said intermediate element have anti-galling characteristics.
4. The earth boring bit of claim 1 wherein the first and second thrust surfaces of said intermediate element have areas with wear resistant characteristics and areas with anti-galling characteristics.
5. The earth boring bit of claim 1 wherein said intermediate element is constructed from a material having anti-galling characteristics.
6. The earth boring bit of claim 1 wherein said intermediate element includes materials with wear resistant characteristics and materials with anti-galling characteristics.
7. The earth boring bit of claim 1 wherein the intermediate thrust element is constructed from a material selected from the group consisting of hardened steel, hardened aluminum bronze and tungsten carbide.
8. The earth boring bit of claim 1 wherein the intermediate thrust element is constructed from a material selected from the group consisting of carburized stainless steel, hardened alloy steel and hardened tool steel.
US00145651A 1971-05-21 1971-05-21 Earth boring bit thrust bearing Expired - Lifetime US3720274A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US14565171A 1971-05-21 1971-05-21

Publications (1)

Publication Number Publication Date
US3720274A true US3720274A (en) 1973-03-13

Family

ID=22513997

Family Applications (1)

Application Number Title Priority Date Filing Date
US00145651A Expired - Lifetime US3720274A (en) 1971-05-21 1971-05-21 Earth boring bit thrust bearing

Country Status (4)

Country Link
US (1) US3720274A (en)
AU (1) AU459366B2 (en)
CA (1) CA954504A (en)
GB (1) GB1368340A (en)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3950041A (en) * 1973-09-12 1976-04-13 Dresser Industries, Inc. Rock bit bearing system for carrying out thrust
US3995367A (en) * 1976-03-01 1976-12-07 Dresser Industries, Inc. Bearing separator and sealing system for rock bit
FR2393184A1 (en) * 1977-06-03 1978-12-29 Sandvik Ab BEARING FOR ROTARY DRILLING TOOLS
US4136748A (en) * 1977-11-07 1979-01-30 The Timken Company Roller-type rock bit and bearing arrangement therefor
US4193463A (en) * 1977-04-27 1980-03-18 Smith International, Inc. Drilling bit fluid-cooled friction bearing
US4235295A (en) * 1979-03-05 1980-11-25 Dresser Industries, Inc. Earth boring bit with renewable bearing surface
US4386663A (en) * 1981-02-25 1983-06-07 Hughes Tool Company Cooled journal bearing
US4410284A (en) * 1982-04-22 1983-10-18 Smith International, Inc. Composite floating element thrust bearing
US4413918A (en) * 1982-05-19 1983-11-08 Smith International, Inc. Thrust bearing for rock bits
US5148879A (en) * 1992-06-17 1992-09-22 Smith International, Inc. Spindle cap bearing for rotary cone rock bits
EP0695851A2 (en) * 1994-08-03 1996-02-07 Camco International Inc. Improvements in or relating to rolling cutter drill bits
US5642942A (en) * 1996-03-26 1997-07-01 Smith International, Inc. Thrust plugs for rotary cone air bits
US6354740B1 (en) 1995-07-28 2002-03-12 Camco International Inc. Rolling cutter drill bits
US6416224B1 (en) 1995-07-28 2002-07-09 Schlumberger Technology Corporation Rolling cutter drill bits
US20040031625A1 (en) * 2002-08-19 2004-02-19 Lin Chih C. DLC coating for earth-boring bit bearings
EP1739277A2 (en) * 2005-07-01 2007-01-03 Smith International, Inc. Graded hardfacing for drill bits
US20070151768A1 (en) * 2003-05-07 2007-07-05 Extreme Machining Australia Pty Ltd Stabilising band for a roller assembly
US8961019B2 (en) 2011-05-10 2015-02-24 Smith International, Inc. Flow control through thrust bearing assembly
US10024107B2 (en) * 2012-12-14 2018-07-17 Epiroc Drilling Tools Llc Rotary drill bit

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2058624A (en) * 1933-09-07 1936-10-27 Chicago Pneumatic Tool Co Roller cutter drill
US2065742A (en) * 1935-03-26 1936-12-29 Chicago Pneumatic Tool Co Roller cutter, spindle, and bearing assembly for earth boring drills
US2075999A (en) * 1935-08-02 1937-04-06 Chicago Pneumatic Tool Co Roller cutter and antifriction bearing assembly for earth boring drills
US2104819A (en) * 1935-03-09 1938-01-11 Hughes Tool Co Roller boring drill
US2444724A (en) * 1944-09-19 1948-07-06 Chicago Pneumatic Tool Co Bearing for rock bits
US2513634A (en) * 1946-04-19 1950-07-04 Reed Roller Bit Co Cone bit bearing
US3480341A (en) * 1967-10-16 1969-11-25 Murphy Ind Inc G W Friction bearing
US3601456A (en) * 1970-03-23 1971-08-24 Myron D Becker Antiskew device for drill bit bearings
US3656764A (en) * 1970-08-31 1972-04-18 William P Robinson Drill bit seal assembly

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2058624A (en) * 1933-09-07 1936-10-27 Chicago Pneumatic Tool Co Roller cutter drill
US2104819A (en) * 1935-03-09 1938-01-11 Hughes Tool Co Roller boring drill
US2065742A (en) * 1935-03-26 1936-12-29 Chicago Pneumatic Tool Co Roller cutter, spindle, and bearing assembly for earth boring drills
US2075999A (en) * 1935-08-02 1937-04-06 Chicago Pneumatic Tool Co Roller cutter and antifriction bearing assembly for earth boring drills
US2444724A (en) * 1944-09-19 1948-07-06 Chicago Pneumatic Tool Co Bearing for rock bits
US2513634A (en) * 1946-04-19 1950-07-04 Reed Roller Bit Co Cone bit bearing
US3480341A (en) * 1967-10-16 1969-11-25 Murphy Ind Inc G W Friction bearing
US3601456A (en) * 1970-03-23 1971-08-24 Myron D Becker Antiskew device for drill bit bearings
US3656764A (en) * 1970-08-31 1972-04-18 William P Robinson Drill bit seal assembly

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3950041A (en) * 1973-09-12 1976-04-13 Dresser Industries, Inc. Rock bit bearing system for carrying out thrust
US3995367A (en) * 1976-03-01 1976-12-07 Dresser Industries, Inc. Bearing separator and sealing system for rock bit
US4193463A (en) * 1977-04-27 1980-03-18 Smith International, Inc. Drilling bit fluid-cooled friction bearing
FR2393184A1 (en) * 1977-06-03 1978-12-29 Sandvik Ab BEARING FOR ROTARY DRILLING TOOLS
US4136748A (en) * 1977-11-07 1979-01-30 The Timken Company Roller-type rock bit and bearing arrangement therefor
US4235295A (en) * 1979-03-05 1980-11-25 Dresser Industries, Inc. Earth boring bit with renewable bearing surface
US4386663A (en) * 1981-02-25 1983-06-07 Hughes Tool Company Cooled journal bearing
US4410284A (en) * 1982-04-22 1983-10-18 Smith International, Inc. Composite floating element thrust bearing
US4413918A (en) * 1982-05-19 1983-11-08 Smith International, Inc. Thrust bearing for rock bits
US5148879A (en) * 1992-06-17 1992-09-22 Smith International, Inc. Spindle cap bearing for rotary cone rock bits
EP0695851A2 (en) * 1994-08-03 1996-02-07 Camco International Inc. Improvements in or relating to rolling cutter drill bits
EP0695851A3 (en) * 1994-08-03 1997-04-02 Camco Int Improvements in or relating to rolling cutter drill bits
US5725313A (en) * 1994-08-03 1998-03-10 Camco International Inc. Rolling cutter drill bits
US6354740B1 (en) 1995-07-28 2002-03-12 Camco International Inc. Rolling cutter drill bits
US6416224B1 (en) 1995-07-28 2002-07-09 Schlumberger Technology Corporation Rolling cutter drill bits
US5642942A (en) * 1996-03-26 1997-07-01 Smith International, Inc. Thrust plugs for rotary cone air bits
US5868502A (en) * 1996-03-26 1999-02-09 Smith International, Inc. Thrust disc bearings for rotary cone air bits
US20040031625A1 (en) * 2002-08-19 2004-02-19 Lin Chih C. DLC coating for earth-boring bit bearings
US20070151768A1 (en) * 2003-05-07 2007-07-05 Extreme Machining Australia Pty Ltd Stabilising band for a roller assembly
EP1739277A2 (en) * 2005-07-01 2007-01-03 Smith International, Inc. Graded hardfacing for drill bits
US20070000698A1 (en) * 2005-07-01 2007-01-04 Smith International, Inc. Graded hardfacing for drill bits
EP1739277A3 (en) * 2005-07-01 2007-10-17 Smith International, Inc. Graded hardfacing for drill bits
US7552783B2 (en) 2005-07-01 2009-06-30 Smith International, Inc. Graded hardfacing for drill bits
US8961019B2 (en) 2011-05-10 2015-02-24 Smith International, Inc. Flow control through thrust bearing assembly
US10024107B2 (en) * 2012-12-14 2018-07-17 Epiroc Drilling Tools Llc Rotary drill bit

Also Published As

Publication number Publication date
AU4179172A (en) 1973-12-20
CA954504A (en) 1974-09-10
GB1368340A (en) 1974-09-25
AU459366B2 (en) 1975-03-27

Similar Documents

Publication Publication Date Title
US3720274A (en) Earth boring bit thrust bearing
US4105263A (en) Journal and pilot bearings with alternating surface areas of wear resistant and anti-galling materials
US4953641A (en) Two cone bit with non-opposite cones
US3990525A (en) Sealing system for a rotary rock bit
US5494123A (en) Drill bit with protruding insert stabilizers
US3784264A (en) Earth boring bit bearing system having a pitted bearing surface
US3235316A (en) Journal bearing with alternating surface areas of wear resistant and antigalling materials
US3628616A (en) Drilling bit with integral stabilizer
US5697461A (en) Rotary drill bit having a non-rotating gauge section
US4098358A (en) Drill bit with hard-faced bearing surfaces
US4200343A (en) Sealing system for a rotary rock bit
US2104819A (en) Roller boring drill
US3604523A (en) Silicon carbide seal for an earth boring bit
US4181185A (en) Thrust flange actuated rock bit lubrication system
US2339161A (en) Cone bit construction
CA1104553A (en) Sealing system for an earth boring cutter
US4209890A (en) Method of making a rotary rock bit with seal recess washer
US4207658A (en) Journal and pilot bearings with alternating surface areas of wear resistant and anti-galling materials
US4193463A (en) Drilling bit fluid-cooled friction bearing
US4330158A (en) Rotary rock bit with improved thrust flange
GB2294071A (en) Rotary drill bit with a reduced tendency for bit whirl
US4279450A (en) Rotary rock bit fluid center seal
US3839774A (en) Method of making an earth boring bit bearing system having a pitted bearing surface
US3885838A (en) Drill bit bearings
US4235295A (en) Earth boring bit with renewable bearing surface