US2884227A - Percussion drill bit for large holes - Google Patents
Percussion drill bit for large holes Download PDFInfo
- Publication number
- US2884227A US2884227A US594290A US59429056A US2884227A US 2884227 A US2884227 A US 2884227A US 594290 A US594290 A US 594290A US 59429056 A US59429056 A US 59429056A US 2884227 A US2884227 A US 2884227A
- Authority
- US
- United States
- Prior art keywords
- drill bit
- bit
- cutting inserts
- drill
- bit body
- 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
Links
- 238000009527 percussion Methods 0.000 title description 8
- 239000011435 rock Substances 0.000 description 9
- 238000005553 drilling Methods 0.000 description 7
- 239000002184 metal Substances 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000012530 fluid Substances 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000005219 brazing Methods 0.000 description 2
- 238000011010 flushing procedure Methods 0.000 description 2
- 150000001247 metal acetylides Chemical class 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Images
Classifications
-
- 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
- E21B10/36—Percussion drill bits
Definitions
- This invention relates generally to drill bits, and more particularly to percussion drill bits for drilling large holes in rock'and other hard surfaces.
- An object of the invention is to provide a drill bit which will drill large holes in rock by a one-step operation when provided with a satisfactory drill feed.
- Another object of the invention is to provide a drill bit which facilitates the drilling of large holes in rock by use of percussion energy without unnecessarily crushing the rock chips produced.
- a more specific object of my invention is to provide a drill bit'adapted to chip off pieces of: rock of such size tharthey mayileasily be. removed from-the percussionarea and the drill hole.
- Still another object of the invention is to provide effective means for the removal of the chipped material from the drilled hole.
- a further object is to provide a drill bit having means for detaching the various cutting elements to allow for interchangeability or substitution of parts whereby drilling of various sizes of holes may be accomplished and easier maintenance of the tool may be effected.
- Fig. 1 shows a perspective view of a drill bit in accordance with the invention
- Fig. 2 shows an elevation sectional view of the bit along line 2--2 of Fig. 3;
- Fig. 3 shows a plan view of the bit
- Figs. 4 and 5 are elevational and plan views of one modification of the inner cutting bit body.
- the body 1 of the drill bit contains projections 2 peripherally arranged about the cutting area and adapted to receive outer cutting inserts 3, formed from a suitable hard metal material, such as one or more metal carbides and a binder.
- a suitable hard metal material such as one or more metal carbides and a binder.
- hard metal is here and below meant a sintered product, consisting of one or more carbides, for example WC and/or other hard materials together with one or more binding metals, as cobalt and/or other metals in the iron group of the periodical system.
- the cutting inserts 3 are preferably brazed to the drill bit, but other suitable securing means, such as clamping, screwing, or welding, may be utilized as desired.
- cutting inserts 3 are shown in the drawings to be circularly arranged, it is also possible to arrange the elements in other configurations, such as an elliptical arrangement for example.
- the direction of the cutting edges is shown to be radial, but it is apparent that the elements may be arranged obliquely or tangentially if desired.
- the inner bit body 4 Centrally arranged within the drill body 1 and removably secured thereto is the inner bit body 4 to which are secured by brazing or other suitable means the inner cutting inserts 5. While the number of cutting elements shown in the drawings is six, it is obvious that the number of elements may be varied as desired. Similarly the orientation of the cutting edges 5 with respect tothe outer cutting inserts 3 may be varied as desired.
- the inner bit body is provided with screw threads 6 adapted to cooperate with the threaded bore 7 in the main bit bodyl to rigidly secure the inner bit body therein.
- the inner cutting inserts 5 are usually in the same plane as the outer cutting inserts 3, although the inner edges may be positioned in front of the plane of the outer cutting edges to reduce wear of the outer cutting inserts.
- the bit may be manufactured so that the plane of the'inner edges will be positioned behind the plane of the outer cutting edges.
- the inner cutting inserts 5 are spaced from the outer cutting inserts 3 by the flat surface 8 of the drill bit body. The minimum distance between of this construction, and in combination with the longil tudinal grooves 9 in the outer surface of the main bitv body, the chipped pieces of rock or stone may passoutwardly from the central portion of the cutting area and subsequently may be removed from the drilled hole.
- a flushing medium maylbe'applied pressure-through the "bit to the 'cuttingarea through'p'assages 10 in the bit body 1 or through passage 11 in the inner bit body 4.
- grooves 9' extend between the outer cutting inserts 3 from the surface 8 longitudinally of the drill bit body, although it is of course possible to form the grooves into angular, spiral or curved paths.
- the outer cutting inserts 3 are supported in the projections of the main bit body by the retaining ring 12 mounted transversely to the longitudinal axis of the bit and secured thereto by suitable securing means, such as by brazing.
- This retaining ring 12 serves not only to support the outer cutting inserts when they are brazed to the associated projections, but also to support the projections against oblique stresses during subsequent drilling, handling and transportation of the tool.
- grooves 9 in the outer surface of the main bit body thus extend radially outwardly from recesses 9 in the support ring and are inclined somewhere between 10 and 50 with the vertical. As shown in the alternate embodiment of Fig. 4, grooves 13 may be placed in the outer surface of the inner bit 4 to further aid in the flushing operation.
- the drill bit body 1 is provided with a threaded bore 14 at the lower portion thereof whereby the drill bit may be secured to the drill rod 15.
- the smallest space between the inner and outer cutting inserts is approximately equal to the length of each of the outer cutting inserts.
- the outer diameter of the drill bit 1 is chosen for the drilling of larger holes, for example somewhere between and mm., but larger or smaller diameter holes may be produced as desired.
- the distance between the inner and outer cutting inserts is on the order of 12 to 20 mm., or in especial cases more.
- a percussion drill bit for drilling large holes in rock or similar substances comprising a cylindrical main bit body having a cutting end and a drill rod securing end, said main bit body having a fiat end surface at the cutting end thereof and a plurality of equally-spaced peripherally-arranged projections axially projecting from said flat end surface, each of said projections having an outer cutting bit mounted therein, a cutting insert retaining ring secured to said fiat end surface of the main bit body in contiguous engagement with a portion of the innermost surfaces of said outer cutting inserts, said main bit body having a central longitudinal bore extending therethrough, an inner bit body screw-threadably mounted within said bore and having a tubular end portion axially projecting from said flat end surface, a plurality of equally-spaced inner cutting bits axially projecting from the extremity of said inner bit body tubular end portion, said outer cutting inserts being concentrically arranged with respect to said inner cutting inserts, said inner and outer cutting inserts each having cutting edges substantially normal to the axis of said main
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- 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)
- Earth Drilling (AREA)
Description
April 28, 1959 J. A. H JALSTEN Y 2,884,227
PERCUSION DRILL BIT FOR LARGE HOLES Filed June 27, 1956 2 Sheets-Sheet 1 INVENTOR MQJ M ATTORNEYS April 28, 1959 J. A. HJALSTEN 2,334,227
. PERCUSSION DRILL BIT FOR LARGE HOLES File d Jun 27, 1956 r z SheetS- -Sheet 2 INVENTOR ATTORNEY 5 PERCUSSION DRILL BIT FOR LARGE HOLES John Anders Hjiilsten, Sandviken, Sweden, assignor to Sandvikens Jernverks Aktiebolag, Sandviken, Sweden, a corporation of Sweden Application June 27, 1956, Serial No. 594,290
2 Claims. (Cl. 255-64) This invention relates generally to drill bits, and more particularly to percussion drill bits for drilling large holes in rock'and other hard surfaces.
An object of the invention is to provide a drill bit which will drill large holes in rock by a one-step operation when provided with a satisfactory drill feed.
Another object of the invention is to provide a drill bit which facilitates the drilling of large holes in rock by use of percussion energy without unnecessarily crushing the rock chips produced.
:A more specific object of my invention is to provide a drill bit'adapted to chip off pieces of: rock of such size tharthey mayileasily be. removed from-the percussionarea and the drill hole.
Still another object of the invention is to provide effective means for the removal of the chipped material from the drilled hole. A further object is to provide a drill bit having means for detaching the various cutting elements to allow for interchangeability or substitution of parts whereby drilling of various sizes of holes may be accomplished and easier maintenance of the tool may be effected.
These and other features of the invention will be more apparent from a study of the following specification when considered in conjunction with the accompanying drawings, in which:
Fig. 1 shows a perspective view of a drill bit in accordance with the invention;
Fig. 2 shows an elevation sectional view of the bit along line 2--2 of Fig. 3;
Fig. 3 shows a plan view of the bit; and
Figs. 4 and 5 are elevational and plan views of one modification of the inner cutting bit body.
Referring now to Fig. l, the body 1 of the drill bit contains projections 2 peripherally arranged about the cutting area and adapted to receive outer cutting inserts 3, formed from a suitable hard metal material, such as one or more metal carbides and a binder. By hard metal is here and below meant a sintered product, consisting of one or more carbides, for example WC and/or other hard materials together with one or more binding metals, as cobalt and/or other metals in the iron group of the periodical system. The cutting inserts 3 are preferably brazed to the drill bit, but other suitable securing means, such as clamping, screwing, or welding, may be utilized as desired. While the cutting inserts 3 are shown in the drawings to be circularly arranged, it is also possible to arrange the elements in other configurations, such as an elliptical arrangement for example. The direction of the cutting edges is shown to be radial, but it is apparent that the elements may be arranged obliquely or tangentially if desired.
Centrally arranged within the drill body 1 and removably secured thereto is the inner bit body 4 to which are secured by brazing or other suitable means the inner cutting inserts 5. While the number of cutting elements shown in the drawings is six, it is obvious that the number of elements may be varied as desired. Similarly the orientation of the cutting edges 5 with respect tothe outer cutting inserts 3 may be varied as desired.
As shown in Figs. 2 and 4 the inner bit body is provided with screw threads 6 adapted to cooperate with the threaded bore 7 in the main bit bodyl to rigidly secure the inner bit body therein.
The inner cutting inserts 5 are usually in the same plane as the outer cutting inserts 3, although the inner edges may be positioned in front of the plane of the outer cutting edges to reduce wear of the outer cutting inserts. For special working conditions the bit may be manufactured so that the plane of the'inner edges will be positioned behind the plane of the outer cutting edges. As shown in Fig. l, the inner cutting inserts 5 are spaced from the outer cutting inserts 3 by the flat surface 8 of the drill bit body. The minimum distance between of this construction, and in combination with the longil tudinal grooves 9 in the outer surface of the main bitv body, the chipped pieces of rock or stone may passoutwardly from the central portion of the cutting area and subsequently may be removed from the drilled hole. v -In v order to aid in this removal of crushed rock. from. the, drilled hole, a flushing medium maylbe'applied pressure-through the "bit to the 'cuttingarea through'p'assages 10 in the bit body 1 or through passage 11 in the inner bit body 4. Thus it may be seen that the chipped pieces of rock will not be caught between the inner and outer cutting inserts and will readily be washed from the drilled bore.
It should be mentioned that the grooves 9' extend between the outer cutting inserts 3 from the surface 8 longitudinally of the drill bit body, although it is of course possible to form the grooves into angular, spiral or curved paths.
In the embodiment as shown in Fig. 2, the outer cutting inserts 3 are supported in the projections of the main bit body by the retaining ring 12 mounted transversely to the longitudinal axis of the bit and secured thereto by suitable securing means, such as by brazing. This retaining ring 12 serves not only to support the outer cutting inserts when they are brazed to the associated projections, but also to support the projections against oblique stresses during subsequent drilling, handling and transportation of the tool.
The grooves 9 in the outer surface of the main bit body thus extend radially outwardly from recesses 9 in the support ring and are inclined somewhere between 10 and 50 with the vertical. As shown in the alternate embodiment of Fig. 4, grooves 13 may be placed in the outer surface of the inner bit 4 to further aid in the flushing operation.
The drill bit body 1 is provided with a threaded bore 14 at the lower portion thereof whereby the drill bit may be secured to the drill rod 15.
During the drilling operation, relatively large chips are produced and by means of the surface 8 in the cutting area of the drill in combination with the grooves 9, 9' and 13 in the bit, no further crushing occurs and an effective use of the percussion energy is presented. As mentioned above, the smallest space between the inner and outer cutting inserts is approximately equal to the length of each of the outer cutting inserts. The outer diameter of the drill bit 1 is chosen for the drilling of larger holes, for example somewhere between and mm., but larger or smaller diameter holes may be produced as desired. The distance between the inner and outer cutting inserts is on the order of 12 to 20 mm., or in especial cases more.
While in accordance with the provisions of the statutes,
r. Ice Patented Apr. 28, 1959 I have illustrated and described the best form of embodiment of my invention-known to me, it will be apparent to those skilled in the artthat changes may be made in the form of the apparatus described without departing from the spirit of my invention as set forth in the appended claims.
.I claim:
1. A percussion drill bit for drilling large holes in rock or similar substances comprising a cylindrical main bit body having a cutting end and a drill rod securing end, said main bit body having a fiat end surface at the cutting end thereof and a plurality of equally-spaced peripherally-arranged projections axially projecting from said flat end surface, each of said projections having an outer cutting bit mounted therein, a cutting insert retaining ring secured to said fiat end surface of the main bit body in contiguous engagement with a portion of the innermost surfaces of said outer cutting inserts, said main bit body having a central longitudinal bore extending therethrough, an inner bit body screw-threadably mounted within said bore and having a tubular end portion axially projecting from said flat end surface, a plurality of equally-spaced inner cutting bits axially projecting from the extremity of said inner bit body tubular end portion, said outer cutting inserts being concentrically arranged with respect to said inner cutting inserts, said inner and outer cutting inserts each having cutting edges substantially normal to the axis of said main bit body, the minimum radial distance between said inner and outer cutting inserts being substantially equal to the maximum length of the cutting edge of said outer inserts, said main bit body having longitudinal grooves on the outer periphery thereof extending between said main body axial projections and said insert retaining ring having recesses in the upper surface thereof in alignment with said longitudinal grooves, said inner bit body having a fluid conductive passage extending longitudinally therethrough and said main bit body having a fluid passage therein which terminates at one end in an opening in the main body flat end surface intermediate said main body projections and said inner bit body and at the other end in communication with said main body longitudinal bore intermediate the drill rod securing end and the inner bit body, whereby particles of drilled material may be readily removed from the annular space intermediate said inner and outer cutting inserts by the introduction of pressure fluid into the main body longitudinal bore from the drill securing end of the main bit body.
2. A percussion drill bit as defined in claim 1 wherein the minimum radial distance between the inner and outer cutting inserts is greater than 12 millimeters.
References Cited in the file of this patent UNITED STATES PATENTS 1,785,405 Candee et al. Dec. 16, 1930 1,813,375 Wright et al. July 7, 1931 2,282,596 Wise et al. May 12, 1942 2,358,052 Brown Sept. 12, 1944 2,502,128 Curtis Mar. 28, 1950 2,807,443 Wyman ..e.. Sept. 24, 11957
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US594290A US2884227A (en) | 1956-06-27 | 1956-06-27 | Percussion drill bit for large holes |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US594290A US2884227A (en) | 1956-06-27 | 1956-06-27 | Percussion drill bit for large holes |
Publications (1)
Publication Number | Publication Date |
---|---|
US2884227A true US2884227A (en) | 1959-04-28 |
Family
ID=24378305
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US594290A Expired - Lifetime US2884227A (en) | 1956-06-27 | 1956-06-27 | Percussion drill bit for large holes |
Country Status (1)
Country | Link |
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US (1) | US2884227A (en) |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2976944A (en) * | 1957-09-27 | 1961-03-28 | Bassinger Tool Company | Percussion drill bit |
US3145789A (en) * | 1962-03-20 | 1964-08-25 | Russell H Lawry | Pilot rock drill |
US3227230A (en) * | 1961-02-21 | 1966-01-04 | Atlas Copco Ab | Combination ring and central drill bit drilling equipment |
US3910361A (en) * | 1972-11-15 | 1975-10-07 | Boehler & Co Ag Geb | Apparatus for drilling and enlarging a bore |
US4540056A (en) * | 1984-05-03 | 1985-09-10 | Inco Limited | Cutter assembly |
US4574895A (en) * | 1982-02-22 | 1986-03-11 | Hughes Tool Company - Usa | Solid head bit with tungsten carbide central core |
US4603750A (en) * | 1984-10-02 | 1986-08-05 | Hughes Tool Company - Usa | Replaceable bit nozzle |
US20050084349A1 (en) * | 2002-02-12 | 2005-04-21 | Karl Kammerer | Drilling tool |
US20070227777A1 (en) * | 2006-03-30 | 2007-10-04 | Sandvik Intellectual Property Ab | Down-the-hole hammer with pilot and method of enlarging a hole |
WO2007114749A1 (en) * | 2006-03-30 | 2007-10-11 | Sandvik Intellectual Property Ab | Down-the-hole hammer, percussion bit assembly and method of enlarging a hole |
WO2017004666A1 (en) * | 2015-07-09 | 2017-01-12 | Fero Group Pty Ltd | Two part drill bit assembly |
US10662716B2 (en) * | 2017-10-06 | 2020-05-26 | Kennametal Inc. | Thin-walled earth boring tools and methods of making the same |
US11065862B2 (en) | 2015-01-07 | 2021-07-20 | Kennametal Inc. | Methods of making sintered articles |
US11065863B2 (en) | 2017-02-20 | 2021-07-20 | Kennametal Inc. | Cemented carbide powders for additive manufacturing |
US11986974B2 (en) | 2019-03-25 | 2024-05-21 | Kennametal Inc. | Additive manufacturing techniques and applications thereof |
US11998987B2 (en) | 2017-12-05 | 2024-06-04 | Kennametal Inc. | Additive manufacturing techniques and applications thereof |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1785405A (en) * | 1927-10-05 | 1930-12-16 | Candee Raphael Rogers | Core-drilling bit |
US1813375A (en) * | 1927-11-15 | 1931-07-07 | Wieman Kammerer Wright Co Inc | Core drill |
US2282596A (en) * | 1939-11-13 | 1942-05-12 | Edward T Wise | Replaceable bit for drill rods |
US2358052A (en) * | 1942-08-27 | 1944-09-12 | Philip B Brown | Arc bit point for rock drills |
US2502128A (en) * | 1948-04-30 | 1950-03-28 | Joy Mfg Co | Rock drill bit |
US2807443A (en) * | 1953-11-02 | 1957-09-24 | Joy Mfg Co | Percussive drill bit |
-
1956
- 1956-06-27 US US594290A patent/US2884227A/en not_active Expired - Lifetime
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1785405A (en) * | 1927-10-05 | 1930-12-16 | Candee Raphael Rogers | Core-drilling bit |
US1813375A (en) * | 1927-11-15 | 1931-07-07 | Wieman Kammerer Wright Co Inc | Core drill |
US2282596A (en) * | 1939-11-13 | 1942-05-12 | Edward T Wise | Replaceable bit for drill rods |
US2358052A (en) * | 1942-08-27 | 1944-09-12 | Philip B Brown | Arc bit point for rock drills |
US2502128A (en) * | 1948-04-30 | 1950-03-28 | Joy Mfg Co | Rock drill bit |
US2807443A (en) * | 1953-11-02 | 1957-09-24 | Joy Mfg Co | Percussive drill bit |
Cited By (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2976944A (en) * | 1957-09-27 | 1961-03-28 | Bassinger Tool Company | Percussion drill bit |
US3227230A (en) * | 1961-02-21 | 1966-01-04 | Atlas Copco Ab | Combination ring and central drill bit drilling equipment |
US3145789A (en) * | 1962-03-20 | 1964-08-25 | Russell H Lawry | Pilot rock drill |
US3910361A (en) * | 1972-11-15 | 1975-10-07 | Boehler & Co Ag Geb | Apparatus for drilling and enlarging a bore |
US4574895A (en) * | 1982-02-22 | 1986-03-11 | Hughes Tool Company - Usa | Solid head bit with tungsten carbide central core |
US4540056A (en) * | 1984-05-03 | 1985-09-10 | Inco Limited | Cutter assembly |
US4603750A (en) * | 1984-10-02 | 1986-08-05 | Hughes Tool Company - Usa | Replaceable bit nozzle |
US20050084349A1 (en) * | 2002-02-12 | 2005-04-21 | Karl Kammerer | Drilling tool |
US20070227777A1 (en) * | 2006-03-30 | 2007-10-04 | Sandvik Intellectual Property Ab | Down-the-hole hammer with pilot and method of enlarging a hole |
WO2007114749A1 (en) * | 2006-03-30 | 2007-10-11 | Sandvik Intellectual Property Ab | Down-the-hole hammer, percussion bit assembly and method of enlarging a hole |
US7673706B2 (en) * | 2006-03-30 | 2010-03-09 | Sandvik Intellectual Property Ab | Down-the-hole hammer with pilot and method of enlarging a hole |
US11065862B2 (en) | 2015-01-07 | 2021-07-20 | Kennametal Inc. | Methods of making sintered articles |
WO2017004666A1 (en) * | 2015-07-09 | 2017-01-12 | Fero Group Pty Ltd | Two part drill bit assembly |
EP3320169A4 (en) * | 2015-07-09 | 2019-03-27 | Fero Group Pty Ltd | Two part drill bit assembly |
US11065863B2 (en) | 2017-02-20 | 2021-07-20 | Kennametal Inc. | Cemented carbide powders for additive manufacturing |
US10662716B2 (en) * | 2017-10-06 | 2020-05-26 | Kennametal Inc. | Thin-walled earth boring tools and methods of making the same |
US11998987B2 (en) | 2017-12-05 | 2024-06-04 | Kennametal Inc. | Additive manufacturing techniques and applications thereof |
US11986974B2 (en) | 2019-03-25 | 2024-05-21 | Kennametal Inc. | Additive manufacturing techniques and applications thereof |
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