WO1995034740A1 - Drilling apparatus - Google Patents

Drilling apparatus Download PDF

Info

Publication number
WO1995034740A1
WO1995034740A1 PCT/FI1994/000249 FI9400249W WO9534740A1 WO 1995034740 A1 WO1995034740 A1 WO 1995034740A1 FI 9400249 W FI9400249 W FI 9400249W WO 9534740 A1 WO9534740 A1 WO 9534740A1
Authority
WO
WIPO (PCT)
Prior art keywords
bit
drilling apparatus
ring
drilling
ring bit
Prior art date
Application number
PCT/FI1994/000249
Other languages
French (fr)
Inventor
Valto ILOMÄKI
Original Assignee
Ilomaeki Valto
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 Ilomaeki Valto filed Critical Ilomaeki Valto
Priority to PCT/FI1994/000249 priority Critical patent/WO1995034740A1/en
Publication of WO1995034740A1 publication Critical patent/WO1995034740A1/en

Links

Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH DRILLING; MINING
    • E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
    • E21B17/02—Couplings; joints
    • E21B17/04—Couplings; joints between rod or the like and bit or between rod and rod or the like
    • E21B17/046—Couplings; joints between rod or the like and bit or between rod and rod or the like with ribs, pins, or jaws, and complementary grooves or the like, e.g. bayonet catches
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH DRILLING; MINING
    • E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B10/00—Drill bits
    • E21B10/64—Drill bits characterised by the whole or part thereof being insertable into or removable from the borehole without withdrawing the drilling pipe
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH DRILLING; MINING
    • E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B7/00—Special methods or apparatus for drilling
    • E21B7/20—Driving or forcing casings or pipes into boreholes, e.g. sinking; Simultaneously drilling and casing boreholes
    • E21B7/208—Driving or forcing casings or pipes into boreholes, e.g. sinking; Simultaneously drilling and casing boreholes using down-hole drives

Definitions

  • a disadvantage of this kind of known drilling appa ⁇ ratus are the tandem percussion shoulders made in the pilot bit, the areas of which remain small due to structural reasons.
  • One shoulder hits the ring bit and another hits the protective tube.
  • the protective tube advances easily, for instance in drilling into rock, the ring bit is mainly hit by the shoulder, whereat the small shoulder area becomes damaged, eventually.
  • the ring drill bit In drilling into soft soil, the ring drill bit must be hit hardly at all and the percussions are even directed over another shoulder to hammer the protective tube, in this case needs the most of the impact energy. Further, when the area of this shoulder is small too, the shoulder or its counterface in the protective tube becomes damaged and wears out easily.
  • the ring bit remains in its position with respect to the protective tube even after detachment of the pilot bit. It can neither turn crosswise nor escape, whereat the pilot bit, when it is being re-installed into drilling position, hits the inside of the ring bit using only slightly bevelled guides. With a construction according to this invention sufficient ring bit areas are achieved in regard to the thickness of the ring bit.
  • the ring bit is hammered from its rear end, whereat the percussion impulse advances straight forward in the bit. When the hammer gear hammers the protective tube forward indirect ⁇ ly only over the bit, the stroke is suppressed a little and does not exert maximum force on the protective tube front edge even though there would be no significant counter-face to take the hit of that stroke.
  • the protective tube is a thin wall construction and its front edge is under hard stress and can therefore tear under the force of the strokes.
  • a thin ring bit construction has been achieved and does not cause any great costs if left in the deep borehole
  • Fig. 1 is a partial cross-section of the drilling apparatus.
  • Fig. 2 is an end view of the drilling apparatus.
  • Fig. 1 is a cross-section of another drilling apparatus.
  • Figure 1 shows the end of the drilling apparatus comprising a pilot bit 2 and a ring bit 5 outside of it.
  • the hammer gear rod 1 which is hit by the hammer gear piston, has a thread onto which the pilot bit is screwed.
  • a nore simple con ⁇ struction can be used also, whereat the rod and pilot bit are made of the same billet, i.e. one piece.
  • Compressed air enters rod 1 and is conducted through holes 11 in bit 2 to the front side of this bit.
  • In the outer edge of the pilot ring there are grooves 6, over which drill waste is transferred to the rear.
  • bit 2 there can be channels 22 even closer to the center running backward through the bit reducing unnecessary rambling of drill waste on bit front side and between bit and the surface being drilled.
  • a groove 8 parallel with the peripherie runs a certain distance out of each groove 6.
  • pins fixed to ring bit 5 and by means of this bayonet connection bits 2 and 5 are interlocked by screwing.
  • Over this bayonet connection ring bit 5 is rotated by bit 2 on drilling in the used direction of rotation.
  • Pins 21 of the ring bit are in groove 8 ends.
  • the pins extrude from grooves 8 into channels 6, whereat the pilot bit can move backward while the ring bit remains in its position.
  • the pins of ring bit 5 are loose in regard to grooves 8 so that the strokes do not get transferred over pins 21 to the ring bit but allow an axial movement as big as the clearance between bits 2 and 5.
  • Figure 2 shows the front of the drill head, whereby holes 11 transmitting compressed air to the front of the drill bit, channels 10 arranged radially for compressed air in the bit front face and channels 6 arranged in the backward direction for drill waste and compressed air can be seen. Further, four grooves 8 are illustrated by a dash line which are on the periphery of pilot bit 2.
  • the front faces of both drill bits 2,5 are furnished with possibly exchangeable working pins 9. Whether the thickness allows, there can also be in the ring bit channels, for instance grooves or holes directed to the rear of the bits.
  • Figure 3 shows another embodiment of the drill bit assembly.
  • a shoulder 18 is connected to pilot bit 20 hitting both the shoulder face 17 of protecting tube 4 and the ring bit 14.
  • Pilot bit 20 has brackets 19 with matching grooves in the ring bit. After detachment of the pilot bit, the ring bit is held in place for instance by a thick cord in groove 15 extruding from one or several holes 16. The ring bit can move axially a distance allowed by the width of groove 15. Also in this case the stroke is suppressed in bit 20 which only in the second stage is hammering the protective tube 4 forward while reducing its liability to damage. Drill waste and compressed air travel through bit 20 along channel 22.
  • both detaching and re- installation of the pilot bit is reliable, since possible rotation of the ring bit does not disturb locking or de- tachment.
  • the rotation of ring bit 5 may disturb detachment and locking if it can rotate easily on the edge of protective tube 3.
  • the periphery of the ring bit When the ring bit is dead and protected in protective tube 3,4 and only a part of its periphery is outside the protective tube while being, simultaneously, controlled and supported by the front edge of the protective tube, the periphery of the ring bit does not touch the tunnel bottom and is not then, due to its rotation, striving to change the direction of its forward travel during drilling.

Abstract

A drilling apparatus boring a hole in soil or rock, the working drill bit assembly of which comprises a ring bit unit (5), boring the outer portion of hole and a pilot bit unit (2), boring the center of hole, which units are detachable from each other and, upon, drilling locked to rotate together at least in one direction and able to move axially in regard to one another in guides (19) or grooves (8). The hammering gear is direct behind the drill bit assembly while bit (2) drilling the bore center is fixed to rod (1) of the hammering gear and the glide guides/grooves (8), are arranged between pilot bit (2) and ring bit (5).

Description

DRILLING APPARATUS
A drilling apparatus boring vertical and horizontal holes in soil or rock, where the drill bit portion, which is mainly drilling the centre of the hole, is detachable from the drill bit portion drilling the outer portion of hole.
Formerly known is a drilling method, where there is in the head of the drilling apparatus a ring bit drilling the outer portion of hole. The drill head is also fitted with a drill bit to work the centre of the hole, whereat the working areas of the drill bits are covered by one another so that the front area of the entire hole gets worked. Both drill bits have a common hammer gear for drill bit hammering, usually operated by compressed air. When a hole is drilled downward and a protective tube put and left in the hole while dril-ling, it is impossible to get the bit that boring the hole outer portion of hole off the hole but it must be left on the bottom of hole. After drilling, the centre drill bit can be pulled out of the hole, if its dimensions are smaller than the diameter of the protective tube. The percussion hammer used as hammer gear is located at the mouth of bore and the stroke transfered to the drill bits by means of the drill rod.
The disadvantage of drilling apparatuses of this kind is that even though one has succeeded in pulling out the pilot bit and the drill rod from the hole after and even during drilling, their reinstallation for continued drilling is generally impossible, since the ring bit remains loose on the front side of the protective tube when it has got detached from the pilot bit and does not keep its position anymore. It can turn crosswise in any direction and even escape in soft soil and it cannot be placed in the tube anymore.
Further, a disadvantage of this kind of known drilling appa¬ ratus are the tandem percussion shoulders made in the pilot bit, the areas of which remain small due to structural reasons. One shoulder hits the ring bit and another hits the protective tube. When the protective tube advances easily, for instance in drilling into rock, the ring bit is mainly hit by the shoulder, whereat the small shoulder area becomes damaged, eventually. In drilling into soft soil, the ring drill bit must be hit hardly at all and the percussions are even directed over another shoulder to hammer the protective tube, in this case needs the most of the impact energy. Further, when the area of this shoulder is small too, the shoulder or its counterface in the protective tube becomes damaged and wears out easily.
With the solution according to this invention a reliable joint between the pilot bit and the drill bit of the outer portion of hole is accomplished, whereat the pilot bit is detachable and also re-mountable with its hammer gear in the drill head. The invention is characterized in what is presented in the enclosed patent claims.
The major advantages of the invention are that the ring bit remains in its position with respect to the protective tube even after detachment of the pilot bit. It can neither turn crosswise nor escape, whereat the pilot bit, when it is being re-installed into drilling position, hits the inside of the ring bit using only slightly bevelled guides. With a construction according to this invention sufficient ring bit areas are achieved in regard to the thickness of the ring bit. The ring bit is hammered from its rear end, whereat the percussion impulse advances straight forward in the bit. When the hammer gear hammers the protective tube forward indirect¬ ly only over the bit, the stroke is suppressed a little and does not exert maximum force on the protective tube front edge even though there would be no significant counter-face to take the hit of that stroke. Usually, the protective tube is a thin wall construction and its front edge is under hard stress and can therefore tear under the force of the strokes. According to the construction as per this invention also a thin ring bit construction has been achieved and does not cause any great costs if left in the deep borehole
Fig. 1 is a partial cross-section of the drilling apparatus.
Fig. 2 is an end view of the drilling apparatus.
Fig. 1 is a cross-section of another drilling apparatus.
Figure 1 shows the end of the drilling apparatus comprising a pilot bit 2 and a ring bit 5 outside of it. The hammer gear rod 1, which is hit by the hammer gear piston, has a thread onto which the pilot bit is screwed. A nore simple con¬ struction can be used also, whereat the rod and pilot bit are made of the same billet, i.e. one piece. Compressed air enters rod 1 and is conducted through holes 11 in bit 2 to the front side of this bit. In the outer edge of the pilot ring there are grooves 6, over which drill waste is transferred to the rear. In bit 2 there can be channels 22 even closer to the center running backward through the bit reducing unnecessary rambling of drill waste on bit front side and between bit and the surface being drilled.
A groove 8 parallel with the peripherie runs a certain distance out of each groove 6. In these grooves there are pins fixed to ring bit 5 and by means of this bayonet connection bits 2 and 5 are interlocked by screwing. Over this bayonet connection ring bit 5 is rotated by bit 2 on drilling in the used direction of rotation. Pins 21 of the ring bit are in groove 8 ends. On rotating in the opposite direction, the pins extrude from grooves 8 into channels 6, whereat the pilot bit can move backward while the ring bit remains in its position. The pins of ring bit 5 are loose in regard to grooves 8 so that the strokes do not get transferred over pins 21 to the ring bit but allow an axial movement as big as the clearance between bits 2 and 5. From pilot bit 2 the strokes travel over the shoulder face 7 to the ring bit. From ring bit 5 the suppressed stroke is transferred as a force pushing the protective tube forward when a ring 12 resting in groove 13 in ring bit 5 has been fastened to the front edge of the protective tube. Edge 13 of ring bit 5 hits ring 12. Upon drilling the ring bit 5 is rotating, the protective tube 12 is not. Ring 12 is at the same time also a sliding ring. A construction as per fig. 1 allows also a sufficient shoulder face to hit ring bit 5. The stroke is transferred also from the pecussion gear 1 over the shoulder face to the pilot bit.
Figure 2 shows the front of the drill head, whereby holes 11 transmitting compressed air to the front of the drill bit, channels 10 arranged radially for compressed air in the bit front face and channels 6 arranged in the backward direction for drill waste and compressed air can be seen. Further, four grooves 8 are illustrated by a dash line which are on the periphery of pilot bit 2. The front faces of both drill bits 2,5 are furnished with possibly exchangeable working pins 9. Whether the thickness allows, there can also be in the ring bit channels, for instance grooves or holes directed to the rear of the bits.
Figure 3 shows another embodiment of the drill bit assembly. A shoulder 18 is connected to pilot bit 20 hitting both the shoulder face 17 of protecting tube 4 and the ring bit 14. Pilot bit 20 has brackets 19 with matching grooves in the ring bit. After detachment of the pilot bit, the ring bit is held in place for instance by a thick cord in groove 15 extruding from one or several holes 16. The ring bit can move axially a distance allowed by the width of groove 15. Also in this case the stroke is suppressed in bit 20 which only in the second stage is hammering the protective tube 4 forward while reducing its liability to damage. Drill waste and compressed air travel through bit 20 along channel 22.
When there are between the pilot bit and ring bit axial or almost axial guides/channels 19, both detaching and re- installation of the pilot bit is reliable, since possible rotation of the ring bit does not disturb locking or de- tachment. In the solution shown in figure 1 the rotation of ring bit 5 may disturb detachment and locking if it can rotate easily on the edge of protective tube 3.
When the ring bit is dead and protected in protective tube 3,4 and only a part of its periphery is outside the protective tube while being, simultaneously, controlled and supported by the front edge of the protective tube, the periphery of the ring bit does not touch the tunnel bottom and is not then, due to its rotation, striving to change the direction of its forward travel during drilling.

Claims

PATENT CLAIMS
1. A drilling apparatus boring a hole in soil or rock, the working drill bit assembly of which comprises a ring bit unit (5), (14) boring the outer hole portion and a pilot bit unit (2), (20), boring the center of hole, which units are detach¬ able from each other and, upon drilling locked to rotate together at least in one direction and able to move axially in regrad to one another in guides (19) or grooves (8), characterized in that the hammering gear is direct behind the drill bit assembly while bit (2), (20) drilling the bore center is fixed to rod (1) of the hammering gear or the units form a unity and the glide guides/grooves (8), (19) are arranged between pilot bit (2), (20) and ring bit (5), (14).
2. A drilling apparatus according to patent claim 1 charac¬ terized in that pilot bit (2), (20), has a shoulder ( 7 ) , (18), out of which the percussion is transmitted to ring bit (5), (14) and outer tube (3), (4).
3. A drilling apparatus according to patent claim 2 charac¬ terized in that the ring bit (5), (14) motion is axially restricted in regard to protective tube (3) , (4) and outer tube (3) is hammered forward by ring bit (5).
4. A drilling apparatus according to any of the patent claims 1 - 3 characterized in that in the outer edge of ring bit (5), (14) there is a groove (13), (15) into which the front edge of protective tube (3), (4) is locked by means of a sliding ring (12) or similar.
5. A drilling apparatus according to any of the patent claims 1 - 4 characterized in that the glide guides are grooves and brackets (19), the direction of which deviates 15° axially from the drilling apparatus.
6. A drilling apparatus according to patent claim 51 charac¬ terized in that the glide guides are formed into a thread with great pitch.
7. A drilling apparatus according to any of the patent claims 1 - 4 characterized in that the axial clearance of the bayonet connection works as an axially running glide guide.
8. A drilling apparatus according to any of the patent claims 1 - 7 characterized in that the rear end of the ring bit is the surface taking the hit of hammering.
9. A drilling apparatus according to any of the patent claims 1 - 8 characterized in that there are channels in ring bit (5), (14) for transfer of drill waste to the back.
10. A drilling apparatus according to any of the patent claims 1 - 9 characterized in that there are exchangeable drill bit buttons (9) in ring bit (5), (14).
PCT/FI1994/000249 1994-06-10 1994-06-10 Drilling apparatus WO1995034740A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/FI1994/000249 WO1995034740A1 (en) 1994-06-10 1994-06-10 Drilling apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/FI1994/000249 WO1995034740A1 (en) 1994-06-10 1994-06-10 Drilling apparatus

Publications (1)

Publication Number Publication Date
WO1995034740A1 true WO1995034740A1 (en) 1995-12-21

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ID=8556582

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/FI1994/000249 WO1995034740A1 (en) 1994-06-10 1994-06-10 Drilling apparatus

Country Status (1)

Country Link
WO (1) WO1995034740A1 (en)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998020229A1 (en) * 1996-11-08 1998-05-14 Sandvik Ab (Publ) Method and apparatus for attaching a casing to a drill bit in overburden drilling equipment
WO2000031373A1 (en) * 1998-11-23 2000-06-02 Ilomaeki Valto A method for mounting a casing shoe on a drilling apparatus
WO2001071152A1 (en) * 2000-03-21 2001-09-27 Dht Technologies Limited Segment for a core drill bit and method of manufacture
AT408567B (en) * 1998-03-06 2002-01-25 Techmo Entw & Vertriebs Gmbh Device for drilling bore holes
WO2010043757A1 (en) * 2008-10-13 2010-04-22 Oy Atlas Copco Rotex Ab Method and drilling apparatus for down-the-hole drilling
EP2339109A2 (en) 2009-12-23 2011-06-29 Lövab Aktiebolag Earth drilling tool and method
WO2012049353A1 (en) * 2010-10-15 2012-04-19 Robit Rocktools Ltd Drill assembly
EP2499325A1 (en) * 2009-11-09 2012-09-19 OY Atlas Copco Rotex AB Method for coupling of a casing tube to a drill bit
WO2015059341A1 (en) 2013-10-22 2015-04-30 Tri-Mach Oy Drilling device
EP2198110A4 (en) * 2007-07-10 2015-12-23 Robit Rocktools Ltd Bit assembly
WO2016183645A1 (en) * 2015-05-15 2016-11-24 Dos Santos Márcio Tunnel treatment method and device with self-lined and self-injectable pipe-roofing
WO2019073123A1 (en) * 2017-10-13 2019-04-18 Mincon Nordic Oy Arrangement and method for installing casing
US10563462B2 (en) 2015-09-14 2020-02-18 Mincon Nordic Oy Drilling device
EP4022159A4 (en) * 2019-08-26 2023-06-14 Mincon Nordic Oy Drilling unit
US11959337B2 (en) 2019-08-26 2024-04-16 Mincon Nordic Oy Drilling unit

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE223486C1 (en) * 1968-11-19
US3635295A (en) * 1969-12-02 1972-01-18 Fenix & Scisson Inc Apparatus for drilling a small borehole downwardly from the bottom of a large borehole
DE4225701C1 (en) * 1992-08-04 1993-12-23 Peter Rubak Rotary drilling appts. with percussion capability - has two coaxial strings with variable rotational speed and direction

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE223486C1 (en) * 1968-11-19
US3635295A (en) * 1969-12-02 1972-01-18 Fenix & Scisson Inc Apparatus for drilling a small borehole downwardly from the bottom of a large borehole
DE4225701C1 (en) * 1992-08-04 1993-12-23 Peter Rubak Rotary drilling appts. with percussion capability - has two coaxial strings with variable rotational speed and direction

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1080813C (en) * 1996-11-08 2002-03-13 桑德维克公司 Method and apparatus for attaching a casing to a drill bit in overburden drilling equipment
WO1998020229A1 (en) * 1996-11-08 1998-05-14 Sandvik Ab (Publ) Method and apparatus for attaching a casing to a drill bit in overburden drilling equipment
AT408567B (en) * 1998-03-06 2002-01-25 Techmo Entw & Vertriebs Gmbh Device for drilling bore holes
WO2000031373A1 (en) * 1998-11-23 2000-06-02 Ilomaeki Valto A method for mounting a casing shoe on a drilling apparatus
WO2001071152A1 (en) * 2000-03-21 2001-09-27 Dht Technologies Limited Segment for a core drill bit and method of manufacture
EP2198110A4 (en) * 2007-07-10 2015-12-23 Robit Rocktools Ltd Bit assembly
WO2010043757A1 (en) * 2008-10-13 2010-04-22 Oy Atlas Copco Rotex Ab Method and drilling apparatus for down-the-hole drilling
EP2499325A1 (en) * 2009-11-09 2012-09-19 OY Atlas Copco Rotex AB Method for coupling of a casing tube to a drill bit
EP2499325A4 (en) * 2009-11-09 2017-03-29 OY Atlas Copco Rotex AB Method for coupling of a casing tube to a drill bit
EP2339109A2 (en) 2009-12-23 2011-06-29 Lövab Aktiebolag Earth drilling tool and method
EP2627851A4 (en) * 2010-10-15 2017-12-27 Robit Rocktools LTD. Drill assembly
CN103261558A (en) * 2010-10-15 2013-08-21 机器人凿岩钻具有限责任公司 Drill assembly
WO2012049353A1 (en) * 2010-10-15 2012-04-19 Robit Rocktools Ltd Drill assembly
WO2015059341A1 (en) 2013-10-22 2015-04-30 Tri-Mach Oy Drilling device
EP3060742A4 (en) * 2013-10-22 2017-06-14 Tri-Mach Oy Drilling device
WO2016183645A1 (en) * 2015-05-15 2016-11-24 Dos Santos Márcio Tunnel treatment method and device with self-lined and self-injectable pipe-roofing
US10563462B2 (en) 2015-09-14 2020-02-18 Mincon Nordic Oy Drilling device
WO2019073123A1 (en) * 2017-10-13 2019-04-18 Mincon Nordic Oy Arrangement and method for installing casing
EP4022159A4 (en) * 2019-08-26 2023-06-14 Mincon Nordic Oy Drilling unit
US11959337B2 (en) 2019-08-26 2024-04-16 Mincon Nordic Oy Drilling unit

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