US3170524A - Roller-type enlarging or reaming bit - Google Patents

Roller-type enlarging or reaming bit Download PDF

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Publication number
US3170524A
US3170524A US20367A US2036760A US3170524A US 3170524 A US3170524 A US 3170524A US 20367 A US20367 A US 20367A US 2036760 A US2036760 A US 2036760A US 3170524 A US3170524 A US 3170524A
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cutting
roller
ribs
drill stem
axis
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US20367A
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Trosken Kurt
Jonschel Werner
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    • 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
    • E21B10/12—Roller bits with discs cutters
    • 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
    • E21B10/26—Drill bits with leading portion, i.e. drill bits with a pilot cutter; Drill bits for enlarging the borehole, e.g. reamers
    • E21B10/28—Drill bits with leading portion, i.e. drill bits with a pilot cutter; Drill bits for enlarging the borehole, e.g. reamers with non-expansible roller cutters
    • 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
    • E21B12/00—Accessories for drilling tools
    • E21B12/06—Mechanical cleaning devices
    • 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
    • E21B7/00—Special methods or apparatus for drilling
    • E21B7/28—Enlarging drilled holes, e.g. by counterboring

Definitions

  • This invention relates to roller-type enlarging or reaming bits having ya plurality of freely rotatable cutting rollers mounted on arms distributed in the form of a star on a base body, as used in so-called pulling or drawing dri-lling for enlarging or reaming out preparatory drillholes through which the drilling rod is then passed.
  • the cutting rollers which sweep over the annular shoulder between the periphery of the enlarged drillhole and the preparatory drillhole during the rotation of the drilling rod, are equipped with a plurality of cutting ribs or serrations distributed in the axial direction over their periphery. These cutting ribs4 are forced into the solid rock under the pulling action exerted on the drilling rod and break Iaway the rock to be broken down peripherally of the drillhole.
  • the cutting ribs which follow very closely one to the other, are subjected to extremely heavy mechanical stresses and Wear out very rapidly even if, accepting the correspondingly higher cost, they are made of specially wear-resistant material.
  • the present invention provides a roller-type enlarging bit which obviates these drawbacks and is achieved by a structure which typically comprises a drill stem to be pulled through a pilot hole, at least two pins radially extending from the trailing end of the drill stem, the axis of each of the pins being inclined toward the direction of travel, and a cutter rotatably mounted on each of the pins, each of the cutters being provided with a plurality of spaced circumferential rows of Wedge-shaped cutting ribs.
  • the pressure component acting in the direction of the preparatory drillhole is obtained by wedge-shaped proling of the cutting ribs in such manner that the inclination of the wedge-shape to a plane normal to the axis of the cutting roller is greater on the side directed towards the preparatory drillhole than on the side facing away therefrom.
  • the action of the cutting rollers constructed in the manner set forth in its essentials above is also assisted in that the cutting ribs of the successive rollers arranged at equiangular separation around the periphery of the drilling rod, for instance the cutting ribs of three such rollers, are offset with respect to one another, so that the succeeding roller in each case becomes operative in the area between the grooves formed by the cutting ribs of the preceding roller.
  • the invention also includes a cutting roller for a roller-type enlarging bit, said cutting roller according to the invention having cutting ribs arranged so that they extend coaxially to one another in the peripheral direction of the roller and lat axial intervals from one another.
  • FIGURE l illustrates in side elevation the general arrangement of the tool inserted in a drillhole which is to be enlarged withparts removed to more clearly illustrate the structure, j
  • FIGURE 2 is a plan view of the general arrangement illustrated in FIG. l showing the bit in its operative position, as in FIG. 1,'inserted in a drill hole bottom of the drillhole, v
  • FIGURE 3 is an enlarged fragmentary elevational view of the cutter illustrated in FIGS. l and 2, and
  • FIGURE 4 is a plan view of a tool similar to that illustrated in FIGURE 2 and specifically illustrating a modivtied form of the arrangement of the cutting ribs on the 'associated cutters.
  • the reference letter a designates the drilling rod of the new drilling tool, which carries the base body b of three-armed type according to the embodiment, on the arms c of which, that is the terminal spigots thereof, the cutting rollers d are exchangeably mounted in the usual manner.
  • FIGURE 2 there can be seen the effect of the offsetting with respect to one another of the series of cutting ribs of the several cutting rollers following one another in the peripheral direction.
  • FIGURE 3 The unique design of the rollers which forms the subject-matter of the invention is apparent in particular from FIGURE 3.
  • the cutting ribs e-there are ve such ribs according to the embodiment-arranged in the direction of the periphery of the roller body at suitable axial intervals from one another.
  • the effective edges of these cutting ribs are so profiled in tilted gable-roof or wedge-like fashion that the inclination of the side i of the wedge-shape f-acing the preparatory drillhole with respect -to a plane normal to the axis of the roller ⁇ is greater than Ithat of the side f remote from the drillhole, which latter side of the gable roof, according to the embodiment, extends parallel to the axis of the drillhole.
  • the cutting ribs are toothed, as indicated in purely diagrammatic manner in FIGURE 3 by showing a few teeth.
  • the cutting ribs e have a wedge-like asymmetrical profile such that the inclination of the faces f' of the ribs e which face toward the body portion of the drill stem with respect to a plane normal to the axis of the roller d is greater than the inclination of the face f directed toward the circumference of the bore hole.
  • arrows g', g" indicate the .resulting force components, namely the breaking-up component g acting in the direction of the axis of the drillhole and the forcing-away component g" acting towards the pre-v paratory drillhole;
  • the circumferences of the cutting ribs which increase in the direction of the periphery of the enlarged drillhole, are determined by the conventional inclined position of the annular bottom of the drillhole.
  • roller-type bit according to ⁇ the invention alsohas the further advantage that manufacture, including the application of the wearresistant FIGURE 4 illustrates a modified form' of the invern tion wherein the cutting ribs on one of the cutting rollers is oset in an axial direction with respect tothe cutting ribs of the succeeding cutting roller. More specically,
  • the cutting roller d is provided withgcutting ribs e which are olset with respect to the cutting ribs e on the cutting the axes of said pin members being inclined yrelatively to the longitudinal axis of said drill stern, ⁇ and a cutting Vroller mounted to rotate about an axis on each of said pin members, each of said cutting Yrollers having a plurality of circumferentially disposed cutting ribs of Wedge-shaped cross sectional prole', the inclination of the portion'of the wedge-shaped cross section of said cutting ribs withV respect to a plane norma-l to theaxisofsaid cutting roller being greater on the side of said cutting rib facing towards '10 lhard surfacing h indicated in FIGURES, is simpler and accordingly cheaper.
  • a rolleri type enlarging bit as claimed in claim l wherein the cutting ribs ofthe one ofk said cutters is oilset with respect to the cutting ribsrof the succeeding one of said cutters.
  • v 3 A ⁇ roller type enlarging bit as claimed in claim 2 wherein the wedge-shaped 'cross-,section of said. cutting ribs is unsymmetrical.
  • a roller type enlarging bit comprising a drill stem to be pulled through a pilot hole, said drill stern having a longitudinal axis, at least two pins1radially extendingl from the trailing end of said drill stem, ⁇ the axis of eachl of said pins being inclined away fromrthe directionof longitudinal travel of said drill stem, and a cutter rotatably mounted on each'of said pins, each of said cutters be- ⁇ ing Yprovided with la plurality of spaced icircumferential rows of wedge-shaped cutting ribs, said drill stem prof viding the sole means for transmitting rotary motion to stem adapted to extend in a pilot drill hole, pin members 35 extending from saidbody portion in a star-like fashion,

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

Description

Feb. 23, 1965 K,vT RosKEN ETAL 3,170,524
- ROLLER-TYPE ENLARGING O R REAMING BIT File r 1 6.- 1960 y 2 Sheets-Sheet 1 A I:Aryan/Tops "ywbfA-u Af," dem @MJ Feb- 23, 1965 K. 'rRosKr-:N Erm. 3,170,524
ROLLER-TYPE ENLARGING 0R REAMING BIT Filed April 6, 1960 2 Sheets-sheet 2 Fig.3
g1 l) /NvE/vrons c AUnited States Patent O 4 Claims. (l. 11s-s3) This invention relates to roller-type enlarging or reaming bits having ya plurality of freely rotatable cutting rollers mounted on arms distributed in the form of a star on a base body, as used in so-called pulling or drawing dri-lling for enlarging or reaming out preparatory drillholes through which the drilling rod is then passed.
In the known types of such tools the cutting rollers, which sweep over the annular shoulder between the periphery of the enlarged drillhole and the preparatory drillhole during the rotation of the drilling rod, are equipped with a plurality of cutting ribs or serrations distributed in the axial direction over their periphery. These cutting ribs4 are forced into the solid rock under the pulling action exerted on the drilling rod and break Iaway the rock to be broken down peripherally of the drillhole. In view of the only linear contact between the cutting ribs and the base of the drillhole the cutting ribs, which follow very closely one to the other, are subjected to extremely heavy mechanical stresses and Wear out very rapidly even if, accepting the correspondingly higher cost, they are made of specially wear-resistant material.
Furthermore, the pulling forces which can be exerted by the drilling rod on tools equipped with such cutting rollers are limited. On a given maximum pulling force being exceeded, this pulling force depending in any individual case on the hardness of the rock, the cutting rollers tend to jam temporarily and then to continue to turn spasmodically through a larger peripheral distance, which results in correspondingly intermittent stresses on the drilling rod.
The present invention provides a roller-type enlarging bit which obviates these drawbacks and is achieved by a structure which typically comprises a drill stem to be pulled through a pilot hole, at least two pins radially extending from the trailing end of the drill stem, the axis of each of the pins being inclined toward the direction of travel, and a cutter rotatably mounted on each of the pins, each of the cutters being provided with a plurality of spaced circumferential rows of Wedge-shaped cutting ribs.
By this arrangement of the cutting ribs, the cutting rollers, under the influence of the pulling force exerted by the drilling stem, effectively break away the rock adjacent the ribs toward the axis of the pilot hole duringthe circular paths ascribed by the rollers.
The pressure component acting in the direction of the preparatory drillhole is obtained by wedge-shaped proling of the cutting ribs in such manner that the inclination of the wedge-shape to a plane normal to the axis of the cutting roller is greater on the side directed towards the preparatory drillhole than on the side facing away therefrom.
The action of the cutting rollers constructed in the manner set forth in its essentials above is also assisted in that the cutting ribs of the successive rollers arranged at equiangular separation around the periphery of the drilling rod, for instance the cutting ribs of three such rollers, are offset with respect to one another, so that the succeeding roller in each case becomes operative in the area between the grooves formed by the cutting ribs of the preceding roller.
3,170,524 Patented Feb. 23, 1965 ICC By designing the cutting rollers according to the invention, completely smooth running of the cutting rollers is obtained and the danger of any jamming of the rollers is eliminated. Due to these facts it becomes possible to operate with greater pulling forces on the drilling Yrod and thus to achieve a higher rate of advance in the drilling operation, intermittent stressing of the drilling rod being entirely obviated.
The invention also includes a cutting roller for a roller-type enlarging bit, said cutting roller according to the invention having cutting ribs arranged so that they extend coaxially to one another in the peripheral direction of the roller and lat axial intervals from one another. Y
The details and further features of the invention will appear from the following description of an embodiment of the new roller-type enlarging bit given with reference to the accompanying drawings, which vare merely diagrammatic.
In the drawings:
FIGURE l illustrates in side elevation the general arrangement of the tool inserted in a drillhole which is to be enlarged withparts removed to more clearly illustrate the structure, j
FIGURE 2 is a plan view of the general arrangement illustrated in FIG. l showing the bit in its operative position, as in FIG. 1,'inserted in a drill hole bottom of the drillhole, v
FIGURE 3 is an enlarged fragmentary elevational view of the cutter illustrated in FIGS. l and 2, and
FIGURE 4 is a plan view of a tool similar to that illustrated in FIGURE 2 and specifically illustrating a modivtied form of the arrangement of the cutting ribs on the 'associated cutters.
In FIGURE l, the reference letter a designates the drilling rod of the new drilling tool, which carries the base body b of three-armed type according to the embodiment, on the arms c of which, that is the terminal spigots thereof, the cutting rollers d are exchangeably mounted in the usual manner.
In FIGURE 2 there can be seen the effect of the offsetting with respect to one another of the series of cutting ribs of the several cutting rollers following one another in the peripheral direction.
The unique design of the rollers which forms the subject-matter of the invention is apparent in particular from FIGURE 3. In this figure there can be seen the cutting ribs e-there are ve such ribs according to the embodiment-arranged in the direction of the periphery of the roller body at suitable axial intervals from one another. As shown at f, the effective edges of these cutting ribs are so profiled in tilted gable-roof or wedge-like fashion that the inclination of the side i of the wedge-shape f-acing the preparatory drillhole with respect -to a plane normal to the axis of the roller `is greater than Ithat of the side f remote from the drillhole, which latter side of the gable roof, according to the embodiment, extends parallel to the axis of the drillhole. Of course, the cutting ribs are toothed, as indicated in purely diagrammatic manner in FIGURE 3 by showing a few teeth. It will be appreciated that the cutting ribs e have a wedge-like asymmetrical profile such that the inclination of the faces f' of the ribs e which face toward the body portion of the drill stem with respect to a plane normal to the axis of the roller d is greater than the inclination of the face f directed toward the circumference of the bore hole.
In FIGURE 3, arrows g', g" indicate the .resulting force components, namely the breaking-up component g acting in the direction of the axis of the drillhole and the forcing-away component g" acting towards the pre-v paratory drillhole;
The circumferences of the cutting ribs, which increase in the direction of the periphery of the enlarged drillhole, are determined by the conventional inclined position of the annular bottom of the drillhole.
In addition to the advantages as regards function already described above, the roller-type bit according to` the invention alsohas the further advantage that manufacture, including the application of the wearresistant FIGURE 4 illustrates a modified form' of the invern tion wherein the cutting ribs on one of the cutting rollers is oset in an axial direction with respect tothe cutting ribs of the succeeding cutting roller. More specically,
the cutting roller d is provided withgcutting ribs e which are olset with respect to the cutting ribs e on the cutting the axes of said pin members being inclined yrelatively to the longitudinal axis of said drill stern,` and a cutting Vroller mounted to rotate about an axis on each of said pin members, each of said cutting Yrollers having a plurality of circumferentially disposed cutting ribs of Wedge-shaped cross sectional prole', the inclination of the portion'of the wedge-shaped cross section of said cutting ribs withV respect to a plane norma-l to theaxisofsaid cutting roller being greater on the side of said cutting rib facing towards '10 lhard surfacing h indicated in FIGURES, is simpler and accordingly cheaper. v
roller d; while the cutting ribs e on the cutting roller d" are-odset with respect to thevcutting ribs e on the cutting roller d. y
:The conventional practice utilized in the assembly and .i use of roller-type enlarging or reaming bits `is described l in detail in the German mining journal entitledfGlckauf, April 23', 1955, page 446.
Of course', the invention irslnot` limited to the form of embodiment described above'in detailand illustrated in the drawings, numerous modifications being possible in` said lbody portion than on the sidefacing away therefrom. A
2. A rolleri type enlarging bit as claimed in claim l wherein the cutting ribs ofthe one ofk said cutters is oilset with respect to the cutting ribsrof the succeeding one of said cutters. v 3. A `roller type enlarging bit as claimed in claim 2 wherein the wedge-shaped 'cross-,section of said. cutting ribs is unsymmetrical. Y
4. A roller type enlarging bit comprising a drill stem to be pulled through a pilot hole, said drill stern having a longitudinal axis, at least two pins1radially extendingl from the trailing end of said drill stem,{the axis of eachl of said pins being inclined away fromrthe directionof longitudinal travel of said drill stem, and a cutter rotatably mounted on each'of said pins, each of said cutters be-` ing Yprovided with la plurality of spaced icircumferential rows of wedge-shaped cutting ribs, said drill stem prof viding the sole means for transmitting rotary motion to stem adapted to extend in a pilot drill hole, pin members 35 extending from saidbody portion in a star-like fashion,
saidl pinsv and rotably mounted cutters and for maintaining pressure on said cutters in the direction of cutting. y
References Cited in the le of this patentl UNITED STATES 'PATENTS 1,661,715V cansan s Mar. 6, 192s" 2,746,719 sengman May 22, 1956 `2,790,625
Dean Apr. 30, 1957

Claims (1)

1. A ROLLER-TYPE ENLARGING BIT COMPRISING A DRILL STEM HAVING A LONGITUDINAL AXIS, A BODY PORTION MOUNTED ON ONE END OF SAID DRILL STEM, THE OTHER END OF SAID DRILL STEM ADAPTED TO EXTEND IN A PILOT DRILL HOLE, PIN MEMBERS EXTENDING FROM SAID BODY PORTION IN A STAR-LIKE FASHION, THE AXES OF SAID PIN MEMBERS BEING INCLINED RELATIVELY TO THE LONGITUDINAL AXIS OF SAID DRILL STEM, AND A CUTTING ROLLER MOUNTED TO ROTATE ABOUT AN AXIS ON EACH OF SAID PIN MEMBERS, EACH OF SAID CUTTING ROLLERS HAVING A PLURALITY OF CIRCUMFERENTIALLY DISPOSED CUTTING RIBS OF WEDGE-SHAPED CROS SECTIONAL PROFILE, THE INCLINATION OF THE PORTION OF THE WEDGE-SHAPED CROSS SECTION OF SAID CUTTING RIBS WITH RESPECT TO A PLANE NORMAL TO THE AXIS OF SAID CUTTING ROLLER BEING GREATER ON THE SIDE OF SAID CUTTING RIB FACING TOWARD SAID BODY PORTION THAN ON THE SIDE FACING AWAY THEREFROM.
US20367A 1959-04-09 1960-04-06 Roller-type enlarging or reaming bit Expired - Lifetime US3170524A (en)

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DEB52777A DE1115662B (en) 1959-04-09 1959-04-09 Extension roller chisel

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3265139A (en) * 1963-12-09 1966-08-09 Continental Oil Co Roller cone drill bit
US3358782A (en) * 1963-07-25 1967-12-19 Bechem Karl Gunter Cutting roller, in particular for roller-type enlarging bits
US3444939A (en) * 1967-12-11 1969-05-20 Karl Gunther Bechem Cutting roller in particular roller-type enlarging bits
CN108457598A (en) * 2018-04-27 2018-08-28 廊坊峰铭石油机械设备有限公司 Reaming helicoid hydraulic motor device

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3231029A (en) * 1963-10-28 1966-01-25 Robbins & Assoc James S Articulated drilling shafts for raise drilling

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1661715A (en) * 1927-05-18 1928-03-06 Anthony E Carlson Rotary bit
US2746719A (en) * 1952-05-22 1956-05-22 Alain R Seligman Drilling device for large bores
US2790625A (en) * 1950-12-12 1957-04-30 Charles A Dean Under-reamers

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1781413A (en) * 1929-07-30 1930-11-11 George C Slocombe Drilling bit

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1661715A (en) * 1927-05-18 1928-03-06 Anthony E Carlson Rotary bit
US2790625A (en) * 1950-12-12 1957-04-30 Charles A Dean Under-reamers
US2746719A (en) * 1952-05-22 1956-05-22 Alain R Seligman Drilling device for large bores

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3358782A (en) * 1963-07-25 1967-12-19 Bechem Karl Gunter Cutting roller, in particular for roller-type enlarging bits
US3265139A (en) * 1963-12-09 1966-08-09 Continental Oil Co Roller cone drill bit
US3444939A (en) * 1967-12-11 1969-05-20 Karl Gunther Bechem Cutting roller in particular roller-type enlarging bits
CN108457598A (en) * 2018-04-27 2018-08-28 廊坊峰铭石油机械设备有限公司 Reaming helicoid hydraulic motor device
CN108457598B (en) * 2018-04-27 2023-08-22 廊坊峰铭石油机械设备有限公司 Reaming screw drilling tool device

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DE1115662B (en) 1961-10-19
GB939653A (en) 1963-10-16
BE589333A (en) 1960-08-01

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