CN113738261A - Top drive type hydraulic drive rotary rock drill - Google Patents
Top drive type hydraulic drive rotary rock drill Download PDFInfo
- Publication number
- CN113738261A CN113738261A CN202110978647.1A CN202110978647A CN113738261A CN 113738261 A CN113738261 A CN 113738261A CN 202110978647 A CN202110978647 A CN 202110978647A CN 113738261 A CN113738261 A CN 113738261A
- Authority
- CN
- China
- Prior art keywords
- impact
- oil groove
- oil
- cylinder
- rock drill
- 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.)
- Pending
Links
- 239000011435 rock Substances 0.000 title claims abstract description 23
- 238000007789 sealing Methods 0.000 claims abstract description 3
- 238000009527 percussion Methods 0.000 claims 1
- 238000004146 energy storage Methods 0.000 abstract description 7
- 239000003921 oil Substances 0.000 description 108
- 239000010720 hydraulic oil Substances 0.000 description 11
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 10
- 239000007789 gas Substances 0.000 description 9
- 238000000034 method Methods 0.000 description 8
- 230000035939 shock Effects 0.000 description 7
- 229910052757 nitrogen Inorganic materials 0.000 description 5
- 230000008569 process Effects 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 3
- 239000000446 fuel Substances 0.000 description 3
- 239000004575 stone Substances 0.000 description 3
- 238000005265 energy consumption Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 239000002689 soil Substances 0.000 description 2
- 239000006096 absorbing agent Substances 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 230000001502 supplementing effect Effects 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
- E21B1/00—Percussion drilling
- E21B1/12—Percussion drilling with a reciprocating impulse member
- E21B1/24—Percussion drilling with a reciprocating impulse member the impulse member being a piston driven directly by fluid pressure
- E21B1/26—Percussion drilling with a reciprocating impulse member the impulse member being a piston driven directly by fluid pressure by liquid pressure
-
- 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
- E21B1/00—Percussion drilling
- E21B1/12—Percussion drilling with a reciprocating impulse member
- E21B1/24—Percussion drilling with a reciprocating impulse member the impulse member being a piston driven directly by fluid pressure
- E21B1/30—Percussion drilling with a reciprocating impulse member the impulse member being a piston driven directly by fluid pressure by air, steam or gas pressure
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Earth Drilling (AREA)
Abstract
The invention provides a top-drive hydraulic rotary rock drill which comprises an impact hammer, a gear box, a buffer cylinder and a drill bit tail, wherein the impact hammer, the gear box, the buffer cylinder and the drill bit tail are sequentially connected, the impact cylinder comprises an impact cylinder, an impact piston and an upper cylinder body, the impact cylinder is fixedly connected with the upper cylinder body in a sealing mode, a limiting ring is embedded on the inner wall of the impact cylinder, the impact piston is arranged in an inner cavity of the impact cylinder, a gas valve assembly is arranged on the upper cylinder body, gas can be filled into a cavity of the upper cylinder body through the gas valve assembly to perform gas energy storage, and the pressure difference in the impact cylinder is controlled through a valve core and a valve sleeve arranged in a valve cavity of the impact hammer, so that the gas and hydraulic pressure can dually drive the impact piston.
Description
Technical Field
The invention relates to a rock drill, in particular to a top-drive type hydraulic rotary rock drill.
Background
Rock drills, which are tools for directly quarrying stone, drill holes are drilled in rock strata so as to put explosive to explode the rock, thereby completing quarrying stone or other stone engineering.
The existing rock drills for drilling in construction sites all adopt pneumatic type, namely compressed air is adopted as a transmission energy mode, the pressure of the compressed air is low and is generally less than 1MPa, and in order to crush rocks and obtain large impact energy, the design of the compression area of a piston is very large, so that the air consumption is large and the energy consumption is large; meanwhile, as more equipment is needed, the transmission distance is long, the pipeline loss is large, the energy utilization rate is low, and the generated noise is large.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the existing pneumatic rock drill has large air consumption and energy consumption due to the lower pressure of compressed air; meanwhile, the problems of low energy utilization rate caused by multiple devices, long transmission distance and large pipeline loss are solved by the top-drive type hydraulic rotary rock drill provided by the invention.
The technical scheme adopted by the invention for solving the technical problems is as follows: the utility model provides a top drive formula gyration rock drill that surges, is including the jump bit, gear box, cushion cylinder and the bore bit tail that connect gradually, the jump bit is including strikeing the jar, strikeing piston, going up cylinder body and spacing ring, strike the jar with go up the sealed fixed connection of cylinder body, the spacing ring inlays to be established strike on the jar inner wall, it sets up to strike the piston in the inner chamber of strikeing the cylinder, the one end of strikeing the piston is passed the spacing ring inserts in the cavity of going up the cylinder body, the other end of strikeing the piston stretches out the inner chamber of strikeing the jar, be equipped with the pneumatic valve subassembly on going up the cylinder body, through the pneumatic valve subassembly can to fill into gas in the cavity of going up the cylinder body.
Further: the impact cylinder is provided with an oil inlet oil duct, a valve sleeve and a valve core, an oil inlet cavity with two open ends is arranged in the valve sleeve, the oil inlet oil duct is communicated with the oil inlet cavity through an opening at the left end of the valve sleeve, the valve core is arranged in the oil inlet cavity and can slide along the oil inlet cavity, and a first oil groove, a second oil groove and a third oil groove are arranged on the inner wall of the valve sleeve.
Further: and a fourth oil groove, a fifth oil groove, a sixth oil groove and a seventh oil groove are formed in the inner wall of the impact cylinder.
Further: the oil inlet oil duct with the fourth oil groove intercommunication, the seventh oil groove with first oil groove intercommunication, the fifth oil groove with the third oil groove intercommunication, sixth oil groove and second oil groove all communicate with the oil tank.
Further: the first rotary motor, the second rotary motor and the motor control valve are arranged on the gear box, and the motor control valve can control the first rotary motor and the second rotary motor to be connected in series and in parallel.
Further: and the impact hammer is provided with an oil inlet energy accumulator and an oil return energy accumulator, and the buffer cylinder is provided with a buffer cylinder energy accumulator.
The top-drive hydraulic rotary rock drill has the advantages that hydraulic oil is introduced into the inner cavity of the impact cylinder through the oil inlet oil circuit to form oil pressure, the pressure difference in the impact cylinder is controlled through the valve core and the valve sleeve arranged in the valve cavity of the impact hammer, and the gas pressure generated by filling nitrogen into the cavity of the upper cylinder body through the gas valve assembly enables gas and hydraulic pressure to carry out double drive on the impact piston.
Drawings
The invention is further illustrated with reference to the following figures and examples.
Fig. 1 is a schematic view of a top drive type hydraulic rotary rock drill of the present invention;
FIG. 2 is a schematic structural view of the impact hammer;
fig. 3 is an enlarged schematic view of a portion a in fig. 2.
In the figure, 1, an impact hammer, 2, a gear box, 3, a buffer cylinder, 4, a drill bit tail, 5, an impact cylinder, 6, an impact piston, 7, an upper cylinder body, 8, a limiting ring, 9, a gas valve assembly, 10, a fuel inlet oil duct, 11, a valve sleeve, 12, a valve core, 13, a first oil groove, 14, a second oil groove, 15, a third oil groove, 16, a fourth oil groove, 17, a fifth oil groove, 18, a sixth oil groove, 19, a seventh oil groove, 20, a first rotary motor, 21, a second rotary motor, 22, a motor control valve, 23, a fuel inlet accumulator, 24, a fuel return accumulator, 25 and a buffer cylinder accumulator are arranged.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention. On the contrary, the embodiments of the invention include all changes, modifications and equivalents coming within the spirit and terms of the claims appended hereto.
In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", and the like, indicate orientations and positional relationships based on the orientations and positional relationships shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be considered as limiting the present invention.
Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "connected" and "connected" are to be interpreted broadly, e.g., as being fixed or detachable or integrally connected; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art. In addition, in the description of the present invention, "a plurality" means two or more unless otherwise specified.
Any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps of the process, and alternate implementations are included within the scope of the preferred embodiment of the present invention in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the present invention.
As shown in fig. 1 and 2, the invention provides a top-drive hydraulic rotary rock drill, which comprises an impact hammer 1, a gear box 2, a buffer cylinder 3 and a drill bit shank 4, which are connected in sequence, wherein the impact hammer 1 comprises an impact cylinder 5, an impact piston 6, an upper cylinder body 7 and a limit ring 8, the impact cylinder 5 is fixedly connected with the upper cylinder body 7 in a sealing manner, the limit ring 8 is embedded on the inner wall of the impact cylinder 5, the impact piston 6 is arranged in an inner cavity of the impact cylinder, one end of the impact piston 6 penetrates through the limit ring 8 and is inserted into a cavity of the upper cylinder body 7, the other end of the impact piston 6 extends out of the inner cavity of the impact cylinder 5, the upper cylinder body 7 is provided with a gas valve assembly 9, and gas can be filled into the cavity of the upper cylinder body 7 through the gas valve assembly 9.
The impact hammer 1 adopts a nitrogen spring and a hydraulic double-striking hybrid impact hammer, one end of an impact piston 6 is inserted into an upper cylinder body 7 to form a closed cavity, nitrogen is filled into the cavity through an air valve assembly 9, when the impact piston 6 is driven to move rightwards in an impact cylinder 5 by hydraulic pressure, the volume of the cavity of the upper cylinder body 7 is reduced, and further gas pressure is generated in the cavity, and during working, one working process of the impact hammer 1 can be divided into return stroke to zero position, positive striking starting, positive striking ending and return stroke starting.
As shown in fig. 3, an oil inlet duct 10, a valve sleeve 11 and a valve core 12 are arranged on the impact cylinder 5, an oil inlet cavity with two open ends is arranged in the valve sleeve 11, the oil inlet duct 10 is communicated with the oil inlet cavity through an opening at the left end of the valve sleeve 11, the valve core 12 is arranged in the oil inlet cavity and can slide along the oil inlet cavity, and a first oil groove 13, a second oil groove 14 and a third oil groove 15 are arranged on the inner wall of the valve sleeve 11.
When the valve core 12 is positioned at the left end of the oil inlet cavity, the first oil groove 13 is communicated with the second oil groove 14; when the valve core 12 is located at the right end of the oil inlet cavity, the first oil groove 13 is communicated with the oil inlet passage 10.
A fourth oil groove 16, a fifth oil groove 17, a sixth oil groove 18 and a seventh oil groove 19 are formed in the inner wall of the impact cylinder 5, and when the impact piston 6 is located on the right side of the inner cavity of the impact cylinder 5, the fourth oil groove 16 is communicated with the fifth oil groove 17; when the impact piston 6 is located on the left side of the inner cavity of the impact cylinder 5, the fifth oil groove 17 is communicated with the sixth oil groove 18, hydraulic oil in the fourth oil groove 16 can apply right pressure to the impact piston 6, and hydraulic oil in the seventh oil groove 19 can apply left pressure to the impact piston 6.
The oil inlet oil passage 10 is communicated with the fourth oil groove 16, the seventh oil groove 19 is communicated with the first oil groove 13, the fifth oil groove 17 is communicated with the third oil groove 15, and the sixth oil groove 18 and the second oil groove 14 are communicated with an oil tank.
When the hydraulic shock absorber starts to work, the shock piston 6 returns to a zero position, the valve core 12 is located at the left end of the valve sleeve 11, the first oil groove 13 is communicated with the second oil groove 14, hydraulic oil in the seventh oil groove 19 flows to an oil tank, the hydraulic oil enters the fourth oil groove 16 through the oil inlet oil passage 10 and enters a gap between the shock cylinder 5 and the shock piston 6 through the fourth right groove, the shock piston 6 is provided with a boss on the right side of the fourth oil groove 16, right pressure is generated on the shock piston 6, the shock piston 6 moves rightwards, the nitrogen spring of the upper cylinder body 7 starts to store energy, when the fourth oil groove 16 is communicated with the fifth oil groove 17, the hydraulic oil in the fifth oil groove 17 flows into the third oil groove 15, the hydraulic oil generates right pressure on the valve core 12 in the third oil groove 15, and the valve core 12 moves rightwards.
When the valve core 12 is located at the right end of the valve sleeve 11, the hydraulic oil in the oil inlet passage 10 enters the seventh oil groove 19 through the first oil groove 13 to form a leftward pressure on the impact piston 6, and at this time, the impact piston 6 is struck by the pressure difference generated by the high-pressure oil in the fourth oil groove 16 and the seventh oil groove 19 and the dual acting force of the nitrogen spring to move leftward.
After the positive striking is finished, the impact piston 6 is positioned at the left end of the impact cylinder 5, the fifth oil groove 17 is communicated with the sixth oil groove 18, so that the hydraulic oil in the third oil groove 15 flows into the oil tank to be decompressed, and the valve core 12 slides leftwards.
And when the return stroke starts, the first oil groove 13 is communicated with the second oil groove 14, so that hydraulic oil in the seventh oil groove 19 flows back to enter the oil tank for pressure relief, the leftward hydraulic pressure of the impact piston 6 is zero, and the impact piston 6 is driven to start the return stroke to the right by virtue of the hydraulic oil in the fourth oil groove 16.
The first rotary motor 20, the second rotary motor 21 and the motor control valve 22 are arranged on the gear box 2, the motor control valve 22 can control the first rotary motor 20 and the second rotary motor 21 to be connected in series and in parallel, double-speed double-torque output is achieved, the series high-speed low torque is suitable for soft soil layers such as sandy soil and building rubbish, the parallel low-speed high torque is suitable for strata such as strong weathered rocks, the series connection and the parallel connection of the first rotary motor 20 and the second rotary motor 21 are very effective in improving the working efficiency, the series connection and the parallel connection of the motors are controlled by the two-position four-way valve, the problem that the motors are dragged by the first motor due to different input flows when connected in series is effectively solved, the oil supplement function of the motors is improved, and the service life of the motors is effectively prolonged.
Be equipped with oil feed energy storage ware 23 and oil return energy storage ware 24 on the jump bit 1, be equipped with buffer cylinder energy storage ware 25 on the buffer cylinder 3, oil return energy storage ware 24 can effectual reduction because of the pipeline vibration that intermittent oil return caused, the pressure fluctuation of oil feed energy storage ware 23 can effectual reduction striking in-process, is not enough to carry out the oil supplementing process to the impact in-process flow simultaneously to improve the striking frequency, buffer cylinder energy storage ware 25 can effectually prevent to strike the influence of in-process pressure fluctuation to buffer cylinder 3 performance.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, a schematic representation of the term does not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
In light of the foregoing description of the preferred embodiment of the present invention, many modifications and variations will be apparent to those skilled in the art without departing from the spirit and scope of the invention. The technical scope of the present invention is not limited to the content of the specification, and must be determined according to the scope of the claims.
Claims (6)
1. A top-drive hydraulic rotary rock drill comprises an impact hammer (1), a gear box (2), a buffer cylinder (3) and a drill shank (4) which are connected in sequence, it is characterized in that the impact hammer (1) comprises an impact cylinder (5), an impact piston (6), an upper cylinder body (7) and a limit ring (8), the impact cylinder (5) is fixedly connected with the upper cylinder body (7) in a sealing way, the limit ring (8) is embedded on the inner wall of the impact cylinder (5), the impact piston (6) is arranged in the inner cavity of the impact cylinder, one end of the impact piston (6) penetrates through the limiting ring (8) and is inserted into the cavity of the upper cylinder body (7), the other end of the impact piston (6) extends out of the inner cavity of the impact cylinder (5), an air valve assembly (9) is arranged on the upper cylinder body (7), the cavity of the upper cylinder body (7) can be filled with gas through the gas valve assembly (9).
2. A top drive type hydraulic drive rotary rock drill according to claim 1, characterized in that the impact cylinder (5) is provided with an oil inlet duct (10), a valve sleeve (11) and a valve core (12), the valve sleeve (11) is provided therein with an oil inlet chamber with openings at both ends, the oil inlet duct (10) is communicated with the oil inlet chamber through the opening at the left end of the valve sleeve (11), the valve core (12) is disposed in the oil inlet chamber and can slide along the oil inlet chamber, and the inner wall of the valve sleeve (11) is provided with a first oil groove (13), a second oil groove (14) and a third oil groove (15).
3. A top drive hydraulic rotary rock drill according to claim 2, characterized in that the inner wall of the percussion cylinder (5) is provided with a fourth oil groove (16), a fifth oil groove (17), a sixth oil groove (18) and a seventh oil groove (19).
4. A top drive hydraulic drive rotary rock drill according to claim 3, characterized in that said oil inlet channel (10) communicates with said fourth oil groove (16), said seventh oil groove (19) communicates with said first oil groove (13), said fifth oil groove (17) communicates with said third oil groove (15), and said sixth oil groove (18) and said second oil groove (14) both communicate with an oil tank.
5. A top drive hydraulic rotary rock drill according to claim 1, characterized in that the gear box (2) is provided with a first rotary motor (20), a second rotary motor (21) and a motor control valve (22), which motor control valve (22) controls the first rotary motor (20) and the second rotary motor (21) in series-parallel connection.
6. A top drive hydraulic drive rotary rock drill according to claim 1, characterized in that the impact hammer (1) is provided with an oil inlet accumulator (23) and an oil return accumulator (24), and the cushion cylinder (3) is provided with a cushion cylinder accumulator (25).
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202110978647.1A CN113738261A (en) | 2021-08-25 | 2021-08-25 | Top drive type hydraulic drive rotary rock drill |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202110978647.1A CN113738261A (en) | 2021-08-25 | 2021-08-25 | Top drive type hydraulic drive rotary rock drill |
Publications (1)
Publication Number | Publication Date |
---|---|
CN113738261A true CN113738261A (en) | 2021-12-03 |
Family
ID=78732661
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202110978647.1A Pending CN113738261A (en) | 2021-08-25 | 2021-08-25 | Top drive type hydraulic drive rotary rock drill |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN113738261A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN114562197A (en) * | 2022-03-02 | 2022-05-31 | 桂林中旺机械制造有限公司 | Hydraulic rock drill with return beating function |
-
2021
- 2021-08-25 CN CN202110978647.1A patent/CN113738261A/en active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN114562197A (en) * | 2022-03-02 | 2022-05-31 | 桂林中旺机械制造有限公司 | Hydraulic rock drill with return beating function |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN101268247B (en) | A percussion hammer for enlarging drilled holes | |
CN102216552A (en) | Drilling apparatus | |
CN113738261A (en) | Top drive type hydraulic drive rotary rock drill | |
US4505340A (en) | Hydropneumatic percussive tool | |
US4658913A (en) | Hydropneumatic percussive tool | |
CN205778537U (en) | Advanced guide type down-hole hammer way-type drilling unit | |
CN108625770A (en) | A kind of the crushing power head and its application method of rotatable impact | |
CN216110507U (en) | Top drive type hydraulic drive rotary rock drill | |
CN107905722A (en) | A kind of closed hydraulic drill | |
CN201087695Y (en) | High wind pressure downhole air hammer | |
CN219138961U (en) | Hydraulic rock drill | |
CN208845097U (en) | A kind of composite impact drilling speed device | |
CN110748297A (en) | Device and method for reducing friction between drilling tool and well wall | |
CN216110508U (en) | Full-hydraulic variable-frequency rock drill controlled by external valve | |
CN114909080A (en) | Pulse hydraulic impactor and drilling and filling integrated pulse grouting method thereof | |
CN210829062U (en) | Anvil valve type hydraulic down-the-hole hammer capable of improving energy utilization rate | |
CN210178269U (en) | Down-the-hole drill and impact hammer with drill rod structure and down-the-hole drill | |
CN110700757B (en) | Combined type link up and surges down-the-hole hammer | |
CN210917533U (en) | Rock digging reamer utilizing air compression impact to assist in crushing | |
CN210152546U (en) | High wind pressure down-the-hole impacter | |
CN208106312U (en) | A kind of composite impact drilling tool | |
CN113738263A (en) | Full-hydraulic variable-frequency rock drill controlled by external valve | |
CN110529038A (en) | A kind of anvil valve type hydraulic in-the-hole hammer | |
CN216110558U (en) | Rotary box with lifting rod function on rock drill | |
CN219622627U (en) | Buffering system of hydraulic rock drill without one-way valve |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination |