US20140262395A1

US20140262395A1 - Drilling apparatus

Info

Publication number: US20140262395A1
Application number: US13/795,991
Authority: US
Inventors: Stuart A. Connell
Original assignee: Caterpillar Global Mining Equipment LLC
Current assignee: Caterpillar Global Mining Equipment LLC; Caterpillar Global Mining LLC
Priority date: 2013-03-12
Filing date: 2013-03-12
Publication date: 2014-09-18

Abstract

A drilling apparatus includes a percussive member configured to generate impact waves, a striking bar configured to receive impact waves from the percussive member, a rotation section at least partly enclosing the striking bar, a flushing section detachably connected to the rotation section, and a vibration isolator attached to the flushing section. The rotation section includes a bearing configured to support the striking bar. Further, the flushing section includes an inlet passage configured to receive a flushing medium.

Description

TECHNICAL FIELD

The present disclosure relates a drilling apparatus, and more particularly to a drilling apparatus for rock.

BACKGROUND

Rock drills typically include a striking bar that is connected to a tool. The striking bar reciprocates and rotates so that the tool may drill through a substrate. The striking bar is partly disposed inside a flushing cavity located in a front part of the rock drill. Further, the striking bar includes an internal channel that is in fluid communication with the flushing cavity. A flushing medium flows through the flushing cavity and the internal channel of the striking bar in order to remove debris from a drilled aperture. PCT Publication No. 2009/148375 discloses a cartridge configured to be inserted in a cavity in a front part of a rock drilling machine having a shank adapter. The cartridge includes a flushing head, and a guide coaxially arranged to create a longitudinal channel. The longitudinal channel is designed as a passage for the shank adapter.

SUMMARY

In one aspect, the present disclosure provides a drilling apparatus including a percussive member configured to generate impact waves, a striking bar configured to receive impact waves from the percussive member, a rotation section at least partly enclosing the striking bar, a flushing section detachably connected to the rotation section, and a vibration isolator attached to the flushing section. The rotation section includes a bearing configured to support the striking bar. Further, the flushing section includes an inlet passage configured to receive a flushing medium.
In another aspect, a flushing section for a drilling apparatus is provided. The flushing section includes a housing detachably connected to a rotation section of the drilling apparatus, and a vibration isolator attached to the housing. The housing includes an inlet passage configured to receive a flushing medium; and an inner surface enclosing a cavity in fluid communication with the inlet passage. Further, the cavity is configured to at least partly enclose a striking bar.
In yet another aspect, a drilling apparatus is provided including a striking bar, a first housing, a second housing detachably coupled to the first housing, and a vibration isolator attached to the first housing. The striking bar including a first end and a second end, the first end being configured to receive impact waves. Further, the first housing includes at least partly encloses the striking bar. The second housing includes an intake passage for a flushing medium, and a cavity in fluid communication with the intake passage. Moreover, the striking bar is at least partly disposed in the cavity.
Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a drilling apparatus;

FIG. 2 is a partial sectional view of the drilling apparatus along a plane A-A′; and

FIG. 3 is a partial sectional view of the drilling apparatus along a plane B-B′.

DETAILED DESCRIPTION

FIGS. 1-3 illustrate various views of a drilling apparatus 100, according to an aspect of the present disclosure. The drilling apparatus 100 may be movably mounted on a feed channel (not shown) so that the drilling apparatus 100 can be moved towards a substrate (for example, a rock formation) for drilling.
FIG. 1 illustrates a perspective view of the drilling apparatus 100. The drilling apparatus 100 includes an oscillation section 102, a rotation section 104, and a flushing section 106. The oscillation section 102 includes an oscillator valve 108 which may be hydraulically actuated. The oscillator valve 108 may impart an oscillating motion to a percussive member (illustrated in FIGS. 2 and 4). The oscillator valve 108 may be adjustable to change a speed of the oscillating motion. However, an electrically or a mechanically driven member (not shown) may also drive the percussive member without departing from the scope of the present disclosure. Further, the oscillating section 102 includes accumulators 110 which may provide fluid power and/or flow to various components of the drilling apparatus 100. The rotation section 104 may be attached to the oscillation section 102 by attachment members 112 passing through flange portions 114. An example of the attachment members 112 may include nut and bolt assemblies. However, the rotation section 104 may be attached to the oscillation section 102 by any other methods, for example, threaded joint, welding, or the like. Alternatively, the rotation section 104 may be integral with the oscillation section 102. Further, the rotation section 104 includes a driving member 115. The driving member 115 may be a hydraulic motor, an electric motor, or the like. The driving member 115 may also provide a variable rotary output.
As illustrated in FIG. 1, the rotation section 104 and the flushing section 106 include a first housing 116 and a second housing 118, respectively. In an embodiment of the present disclosure, the first housing 116 includes a first housing section 116A and a second housing section 116B. The first housing section 116A and the second housing section 116B may be connected to each other by the attachment members 112. However, in an alternate embodiment, the first housing section 116A and the second housing section 116B may be integral with each other. In an embodiment of the present disclosure, the second housing 118 may be detachably coupled to the second housing section 116B of the first housing 116. A splash guard 117 may provide debris/water splash protection for the second housing section 116B and the second housing 118. Further, a vibration isolator 119 is attached to the first housing section 116A and the second housing 118. As illustrated in FIG. 1, a striking bar 120 projects out of the second housing 118. Moreover, the flushing section 106 includes a fluid coupler 122 coupled to the second housing 118.
FIG. 2 illustrates a partial sectional view of the drilling apparatus 100 along an axis A-A′. As illustrated in FIG. 2, the oscillator section 102 includes an oscillator housing 202, which partly encloses the percussive member 204. The percussive member 204 is supported by oscillator bearings 206 and 208. The percussive member 204 generates impact waves by oscillating along a direction “S”, as illustrated in the figure. Further, the percussive member 204 extends into the first section housing 116A of the rotation section 104. The percussive member 204 may transfer impact waves to the striking bar 120 by contacting a first end 210 of the striking bar 120. Alternatively, the percussive member 204 may generate and transfer impact waves to the striking bar 120 in a non-contact manner, for example, by magnetostriction. Further, a second end 212 of the striking bar 120 may be detachably coupled to a tool (for example, a drill coupling, a drill rod and/or a drill bit). The striking bar 120 may include threads for coupling with the drill bit. Alternatively, the drill bit and the striking bar 120 may be integral.
Further, the driving member 115 is attached to a lower part 214 of the first housing section 116A. An output part 216 of the driving member 115 is coupled to a first transmission member 218. The first transmission member 218 may engage with a second transmission member 220. The first housing section 116A and the second housing section 116B may at least partly enclose the second transmission member 220 and the striking bar 120. Further, the striking bar 120 and the second transmission member 220 may be coupled such that the striking bar 120 rotates with the second transmission member 220. Thus, the first transmission member 218 and the second transmission member 220 may transfer rotary power from the output member 216 to the striking bar 120. The first transmission member 218 and the second transmission member 220 may include any type of gear, for example, a spur gear, a helical gear, a bevel gear, or the like. In an embodiment of the present disclosure, the first transmission member 218 and the second transmission member 220 may have a transmission ratio that is optimum for drilling. However, any other type of transmission may be provided, for example, a belt transmission, a friction transmission, or a combination thereof. The transmission ratio may also be adjustable. Alternatively, the output member 216 may be directly coupled to the striking bar 120.
The percussive member 204 and the driving member 115 therefore oscillate and rotate the striking bar 120. Consequently, the tool, which is coupled with the striking bar 120, also oscillates and rotates, thereby fracturing and drilling through a substrate.
As illustrated in FIG. 2, the first section 116A and the second housing section 116B at least partly encloses a first bearing 224A and a second bearing 224B, respectively. Alternatively, the first housing section 116A and the second housing section 116B may together at least partly enclose a single bearing. The first bearing 224A and the second bearing 224B may be bushings made of bronze alloy. Alternatively, the first bearing 224A and the second bearing 224B may be roller bearings, fluid bearings, or the like. The first bearing 224A and the second bearing 224B may support the striking bar 120. Further, the first housing section 116A and the second housing section 116B at least partly encloses a first transmission bearing 226A and a second transmission bearing 226B, respectively. The first and second transmission bearings 226A, 226B may support the second transmission member 220.
As illustrated in FIG. 2, the vibration isolator 119 is connected to the second housing section 116B and the second housing 118. Further, the vibration isolator 119 includes an elastomeric member 228, a support member 230, a fastener 232 and an inner member 234. As illustrated in FIG. 2, the support member 230 and the inner member 234 retain the elastomeric member 228 between them. The elastomeric member 228 may be slidably coupled to the inner member 234. Moreover, the elastomeric member 228 includes projections 235 which may engage with the support member 230 to lock the elastomeric member 228 in position. The support member 230 is connected to an attachment portion 236 of the second housing section 116B. In an embodiment of the present disclosure, one or more fastening members (not shown) may detachably connect the support member 230 to the attachment portion 236. Further, the fastener 232 passes through the inner member 234 and into second housing 118. Thus, the fastener 232 secures the inner member 234 and the elastomeric member 228 to the second housing 118. The fastener 232 may include threads than engage with corresponding threads of the inner member 234 and/or the second housing 118. In an embodiment of the disclosure, the vibration isolator 119 may be made of rubber. The support member 230 may be made of aluminum. Further, the fastener 232 may be a bolt made of steel.
FIG. 3 illustrates a partial sectional view of the drilling apparatus 100 along an axis B-B′. As illustrated in FIG. 3, the second housing 118 includes an inner surface that encloses a cavity 302. Sealing members 304 are disposed at both ends of the cavity 302. The sealing members 304 may be gaskets. Further, the second housing 118 includes an inlet passage 306 in fluid communication with the cavity 302. The fluid coupler 122 includes a fluid passage 308 which in fluid communication with the inlet passage 306. The fluid coupler 122 includes a coupling portion 309 which may be connected to a pipe and/or hose (not shown). The pipe and/or hose may be connected to a source of a flushing medium.
As illustrated in FIG. 3, the striking bar 120 includes an internal channel 310 and an inlet port 312. In an embodiment of the present disclosure, the inlet port 312 may be formed by cross drilling. The inlet port 312 is in fluid communication with the inlet port 312 and the cavity 302. The inlet channel 310 may extend longitudinally along a length of the striking bar 120. Further, the inlet channel 310 includes an exit 314 at the second end 212 of the striking bar 120. In an alternative embodiment of the disclosure, the striking bar 120 may include multiple inlet ports spaced radially and/or axially around the inlet channel 310. Further, the inlet channel 310 may include multiple exits proximate the second end 212 of the striking bar 120. Moreover, the striking bar 120 may include a network of inlet channels.
During a drilling operation, a flow path “F” of the flushing medium is as follows: the fluid passage 308, the inlet passage 306, the cavity 302, the inlet port 312, the inlet channel 310 and finally the exit 314. A tool, which may be attached to the striking bar 120, includes a corresponding channel. The flushing medium may be any fluid, for example, water, air, or the like. In an embodiment of the present disclosure, the water may be recycled mine water. The sealing members 304 may substantially prevent leakage of the flushing medium from the cavity 302.
As illustrated in FIG. 3, the second housing section 116B includes a first connecting portion 316, while the second housing 118 includes a second connecting portion 318. In an embodiment, the first connecting portion 316 detachably engages the second connecting portion 318. The splash guard 117 covers the first connecting portion 316 and the second connecting portion 318. A clamping member 320 may secure the splash guard 117 to the second housing 118.

INDUSTRIAL APPLICABILITY

The present disclosure relates to the drilling apparatus 100 which includes the oscillation section 102, the rotation section 104, and the flushing section 106. The striking bar 120 is at least partly enclosed by the rotation section 104 and the flushing section 106. A tool may be attached to the second end 212 of the striking bar 120.
During a drilling operation, the striking bar 120 may bend due to irregularities in a substrate. The striking bar 120 may also get stuck inside the substrate. This may exert a bending moment on the striking bar 120 and create localized stress concentrations at the inlet port 312. Consequently, the striking bar 120 may fail at the inlet port 312. The bending and/or failure of the striking bar 120 may damage various components of the flushing section 106.
The flushing section 106, according to an embodiment of the present disclosure, is separate from and detachably coupled to the rotation section 104. Further, as illustrated schematically in FIG. 3, the separate flushing section 106 may displace a bending moment “BM”, sustained by the striking bar 120 during an operation of the drilling apparatus 100, to the first bearing 224A and the second bearing 224B. This may substantially prevent an occurrence of localized stress concentrations at the inlet port 312 of the striking bar 120. Therefore, likelihood of damage to the flushing section 106 and/or the striking bar 120 may be minimized. The vibration isolator 119 may also absorb vibrations, and provide additional support to the flushing section 106, especially when the striking bar 120 bends during an operation of the drilling apparatus 100. Further, due to the detachable coupling between the second housing section 116B and the second housing 118, the second housing 118 may be able to bend to a certain degree, without any breakage, in order to accommodate a bending of the striking bar 120.
During a drilling operation, the striking bar 120 may form a drilled aperture in a substrate. A flushing medium may be passed through the internal channel 310 of the striking bar 120 to remove debris from the drilled aperture. The flushing medium may be recycled mine water which is acidic. The impurities may corrode parts of the striking bar 120 and the flushing section 106. For example, a bearing provided in the flushing section 106 may wear prematurely due to the corroding effect of the flushing medium. Further, portions of the second housing 118 enclosing the cavity 302 may also undergo corrosion. Consequently, the sealing member 304 may be unable seal the flushing medium within the cavity 302, resulting in leakage of the flushing medium from the flushing section 106. Thus, debris may not get flushed effectively from the drilled aperture. This may negatively impact a drilling operation.
The drilling apparatus 100 may require repairs and/or replacements of one or more components at least partly due to the aforementioned reasons. In case the flushing section 106 is integral with the rotation section 104, repair and/or replacement of various components of the drilling apparatus 100 may be complicated, time consuming and expensive, for example, replacement of a bearing located in the flushing section 106. In some cases, replacement of the entire flushing section 106 and the rotation section 104 may be necessary. This may render any onsite repairs and/or replacements difficult or impossible. Further, an operator may not be able to perceive any damage to the flushing section 106, if the flushing section 106 is integral with the rotation section 104, and continue operating the drilling apparatus 100. This may worsen the damage to the drilling apparatus 100.
The flushing section 106, according to an embodiment of the present disclosure, is separate from and detachably coupled to the rotation section 104. Consequently, repairs and/or replacements of the flushing section 106 may be simpler, cost effective and fast. Damage may also be restricted to the flushing section 106. In an embodiment of the present disclosure, the flushing section 106 may be easily removed by detaching the second housing 118 from the second housing section 116B. Further, the vibration isolator 119 may be conveniently detached from the flushing section 106 by removing the fastener 232. Replacement flushing sections 106 may be present onsite to minimize downtimes. The flushing section 106 also does not include any bearing which may otherwise be susceptible to corrosion and damage. As illustrated in FIG. 2, the rotation section 104 includes the first bearing 224A and the second bearing 224B. Thus, no bearing need to be replaced in the flushing section 106, further reducing cost, time and complexity of repairs and/or replacements.
During an operation of the drilling apparatus 100, in case the flushing section 106 undergoes any damage, leakage of the flushing medium and/or off-center displacement of the second housing 118 may immediately alert an operator. The operator may immediately cease the drilling operation, thereby preventing further damage to the drilling apparatus 100.
Embodiments of this disclosure may be applied to a drilling apparatus 100 which may be used in surface or underground applications. The drilling apparatus 100 may be driven hydraulically, pneumatically, electrically, mechanically, or a combination thereof. Further, the drilling apparatus 100 may be disposed on a drilling rig. The drilling rig may be adjustably mounted on a boom of a vehicle. Alternatively, the drilling rig may be adjustably mounted on a support and an operator may control the drilling rig.
Although the embodiments of this disclosure as described herein may be incorporated without departing from the scope of the following claims, it will be apparent to those skilled in the art that various modifications and variations can be made. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure. It is intended that the specification and examples be considered as exemplary only, with a true scope being indicated by the following claims and their equivalents.

Claims

What is claimed is:

1. A drilling apparatus comprising:

a percussive member configured to generate impact waves;

a striking bar configured to receive impact waves from the percussive member;

a rotation section at least partly enclosing the striking bar, the rotation section comprising a bearing configured to support the striking bar;

a flushing section detachably connected to the rotation section, the flushing section comprising an inlet passage configured to receive a flushing medium; and

a vibration isolator attached to the flushing section.

2. The drilling according to claim 1, wherein the vibration isolator includes:

an elastomeric member;

a support member configured to receive the elastomeric member, the support member being connected to the rotation section; and

a fastener configured to secure the elastomeric member to the flushing section.

3. The drilling apparatus according to claim 1, wherein the striking bar includes an internal channel and an inlet port, and wherein the internal channel is in fluid communication with the inlet port.

4. The drilling apparatus according to claim 3, wherein the flushing section further includes a cavity at least partly enclosing the striking bar, and wherein the cavity is in fluid communication with the inlet passage and the inlet port of the striking bar.

5. The drilling apparatus according to claim 4, wherein the flushing section further includes a sealing member disposed at an end of the cavity.

6. The drilling apparatus according to claim 1, wherein the bearing includes a front bearing and a rear bearing.

7. A flushing section for a drilling apparatus comprising:

a housing detachably connected to a rotation section of the drilling apparatus, the housing comprising:

an inlet passage configured to receive a flushing medium; and

an inner surface enclosing a cavity, the cavity being configured to at least partly enclose a striking bar, wherein the cavity is in fluid communication with the inlet passage; and

a vibration isolator attached to the housing.

8. The flushing section according to claim 9, wherein the vibration isolator includes:

an elastomeric member;

a support member configured receive the elastomeric member, the support member being connected to the rotation section; and

a fastener configured to secure the elastomeric member to the flushing section.

9. The flushing section according to claim 7, wherein the striking bar includes an internal channel and an inlet port, and wherein the internal channel is in fluid communication with the inlet port.

10. The flushing section according to claim 9, wherein the cavity is in fluid communication with the inlet port of the striking bar.

11. The flushing section according to claim 7 further includes a sealing member disposed at an end of the cavity.

12. The flushing section according to claim 7, wherein the rotation section includes a bearing configured to support the striking bar.

13. The flushing section according to claim 12, wherein the bearing includes a front bearing and a rear bearing.

14. A drilling apparatus comprising:

a striking bar comprising a first end and a second end, the first end being configured to receive impact waves;

a first housing at least partly enclosing the striking bar;

a second housing detachably coupled to the first housing, the second housing comprising an intake passage for a flushing medium and a cavity in fluid communication with the intake passage, the striking bar being at least partly disposed in the cavity; and

a vibration isolator attached to the first housing.

15. The drilling apparatus according to claim 14, wherein the first housing is disposed proximal to the first end and the second housing is disposed proximal to the second end.

16. The drilling apparatus according to claim 14, wherein the striking bar includes an internal channel and an inlet port, and wherein the internal channel is in fluid communication with the inlet port.

17. The drilling apparatus according to claim 16, wherein the cavity is in fluid communication with the inlet port of the striking bar.

18. The drilling apparatus according to claim 14 further includes a sealing member disposed at an end of the cavity.

19. The drilling apparatus according to claim 14, wherein the first housing at least partly encloses a bearing configured to support the striking bar.

20. The drilling apparatus according to claim 19, wherein the bearing includes a front bearing and a rear bearing.