CN212536317U - Closed hydraulic circuit of rotary drill - Google Patents
Closed hydraulic circuit of rotary drill Download PDFInfo
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- CN212536317U CN212536317U CN202020919019.7U CN202020919019U CN212536317U CN 212536317 U CN212536317 U CN 212536317U CN 202020919019 U CN202020919019 U CN 202020919019U CN 212536317 U CN212536317 U CN 212536317U
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Abstract
The utility model provides a closed hydraulic circuit of a rotary drill rig, which comprises a left oil supply circuit and a right oil supply circuit, wherein the left oil supply circuit and the right oil supply circuit are both connected with a constant delivery pump, the constant delivery pump is connected with an oil tank, a left walking motor and a rotary motor are connected in parallel on the left oil supply circuit, and a right walking motor and a pressurizing hydraulic cylinder are connected in parallel on the right oil supply circuit; the left oil supply loop comprises a left variable pump, a first two-position three-way hydraulic control reversing valve and a second two-position three-way hydraulic control reversing valve, wherein the first two-position three-way hydraulic control reversing valve and the second two-position three-way hydraulic control reversing valve are respectively arranged at an oil outlet end and an oil return end of the left variable pump. The utility model discloses a two variable pump fuel feeding among to hydraulic system, wherein left variable pump walking motor and rotary motor fuel feeding left adopts right variable pump to the pressurized hydraulic cylinder and the hydraulic motor fuel feeding that walks rightwards to constitute closed hydraulic circuit, make hydraulic system's simple structure, do not need big oil tank, and loss of pressure is low, and the heat production is few.
Description
Technical Field
The utility model relates to a rotary drill's closed hydraulic circuit belongs to hydraulic control technical field.
Background
Because the open hydraulic circuit of the rotary drill rig has the defects of complex structure, large heat production quantity, large pressure loss and the like, the existing rotary drill rig mostly adopts a closed hydraulic circuit, but the closed hydraulic circuit has the following problems: 1. when the rotary drill works, the requirements of drilling are met, the rotary drill does not walk, does not drill when walking, and is difficult to realize only by using a single closed loop; 2. the existing roller drill closed hydraulic circuit has a plurality of hydraulic elements, so that the hydraulic closed circuit is extremely complex; 3. when the rotary drill rig is in a drilling working condition, oil is fed into a rodless cavity of the pressurizing hydraulic cylinder, oil is discharged from a rod cavity, and oil needs to be supplemented to the side of the rod cavity due to the fact that the areas of the two cavities are different; 4. when the working condition is lifted, the oil inlet of the rod cavity is less than the oil outlet of the rodless cavity, and an overflow valve needs to be added on the side of the rodless cavity, so that redundant oil enters the rod cavity; 5. when the roller-cone drilling machine is pushed downwards, the drill bit is influenced by gravity and can cause damage to a drill rod and a drilling tool, so that a special balance valve needs to be added to maintain the back pressure of a low-pressure side; 6. because the working condition of the roller-bit rig is very complicated, when the roller-bit rig works on a slope, the phenomenon of slope slipping occurs due to self gravity, and therefore a hydraulic element is damaged.
SUMMERY OF THE UTILITY MODEL
Problem to the hydraulic circuit existence of current rotary drill, the utility model provides a rotary drill's closed hydraulic circuit to overcome not enough among the prior art.
The technical scheme of the utility model: a closed hydraulic circuit of a rotary drill comprises a left oil supply circuit and a right oil supply circuit, wherein the left oil supply circuit and the right oil supply circuit are both connected with a constant delivery pump, the constant delivery pump is connected with an oil tank, a left walking motor and a rotary motor are connected in parallel on the left oil supply circuit, and a right walking motor and a pressurizing hydraulic cylinder are connected in parallel on the right oil supply circuit; the left oil supply loop comprises a left variable pump, a first two-position three-way hydraulic control reversing valve and a second two-position three-way hydraulic control reversing valve, wherein the first two-position three-way hydraulic control reversing valve and the second two-position three-way hydraulic control reversing valve are respectively arranged at an oil outlet end and an oil return end of the left variable pump; the right oil supply loop comprises a right variable pump, a third two-position three-way hydraulic control reversing valve and a fourth two-position three-way hydraulic control reversing valve which are respectively arranged at an oil outlet end and an oil return end of the right variable pump, an oil inlet end and an oil return end of the right walking motor are respectively connected to one of the through ends of the third two-position three-way hydraulic control reversing valve and the fourth two-position three-way hydraulic control reversing valve, and an oil inlet end and an oil return end of the pressurizing hydraulic cylinder are respectively connected to the other through end of the third two-position three-way hydraulic control reversing valve and the fourth two-position three-way hydraulic control reversing valve; the first two-position three-way hydraulic control reversing valve, the second two-position three-way hydraulic control reversing valve, the third two-position three-way hydraulic control reversing valve and the fourth two-position three-way hydraulic control reversing valve are all connected with the oil outlet end of the four-position four-way manual reversing valve in parallel, and the oil inlet end of the four-position four-way manual reversing valve is connected with the dosing pump.
Furthermore, a left cleaning valve group and a right cleaning valve are respectively connected in parallel on the left oil supply loop and the right oil supply loop.
Further, the oil inlet end of the constant delivery pump is provided with a filter.
Furthermore, a walking oil supplementing one-way valve and a walking buffer overflow valve are connected in series on the oil inlet end and the oil return end of the left walking motor and the right rotary motor, and a pressure valve bank and a two-position two-way electromagnetic reversing valve are connected in parallel between the oil inlet end and the oil return end of the left walking motor and the right rotary motor.
Furthermore, two rotary oil-supplementing one-way valves and two rotary buffer overflow valves are connected in parallel between the oil inlet end and the oil return end of the rotary motor.
Furthermore, the oil inlet end and the oil return end of the pressurizing hydraulic cylinder are both connected in series with a one-way sequence valve, and two pressurizing oil-supplementing one-way valves and two pressurizing buffer overflow valves are connected in parallel between the oil inlet end and the oil return end of the pressurizing hydraulic cylinder.
Due to the adoption of the technical scheme, the utility model has the advantages of:
1. this hydraulic circuit adopts two variable pump to supply oil among the hydraulic system, and wherein left variable pump is the walking motor left and is the gyration motor fuel feeding, adopts right variable pump to the hydraulic cylinder that pressurizes and the hydraulic motor fuel feeding of walking right to constitute closed hydraulic circuit, make hydraulic system's simple structure, do not need big oil tank, and pressure loss is low, and the heat production is few, compares open system, and the competitive advantage of closed system is stronger in big-and-middle-sized rig.
2. The hydraulic loop adopts a four-position four-way manual reversing valve and four two-position three-way hydraulic control reversing valves, so that the roller-bit drilling machine can realize the independent work of a walking mechanism (a left walking motor, a right walking motor) and a working mechanism (a rotary motor and a pressurizing hydraulic cylinder), and can ensure that the roller-bit drilling machine does not walk when drilling and does not drill when walking, thereby greatly saving the cost of hydraulic elements.
3. Although the heat production amount of the closed loop is small, the heat in the hydraulic oil cannot be released for a long time, so that the cleaning valve group is added into the hydraulic system, and the heat production amount of the system is greatly reduced.
4. In order to prevent insufficient supply of hydraulic oil caused by the cleaning valve group, a fixed displacement pump is arranged in a hydraulic loop to serve as auxiliary pressure supply, and the hydraulic system can supplement the hydraulic oil returned to an oil tank from the cleaning valve group to the system through the fixed displacement pump.
5. The walking oil-supplementing check valve, the walking buffer overflow valve and the pressure valve group are added into the hydraulic loop to form a walking speed-limiting loop, so that the phenomenon that a drilling machine slips down when working on a slope is prevented.
6. In order to prevent the feeding vertical hydraulic cylinder in the roller-bit drilling machine from automatically sliding down or overspeed movement due to the weight of a drill bit when in work, which can cause the damage of the drill bit or the hydraulic cylinder and the unstable drilling movement, a one-way sequence valve is connected in series on an oil inlet path and an oil return path in a pressurizing loop to form a balancing loop and balance the dead weight of the drill bit.
7. Because the load borne by the roller-cone drilling machine during drilling is large, great hydraulic impact can be generated during drilling or stopping, especially, obstacles are needed to stop the action suddenly during drilling, the hydraulic impact can cause the vibration of a hydraulic element and a hydraulic system, mechanical equipment can generate great noise, and even the hydraulic element can be damaged. Therefore, the oil return path and the oil inlet path of each actuating element in the hydraulic circuit are connected with the buffer valve and the one-way valve in parallel to form the parallel buffer circuit, and when the hydraulic oil pressure in the working cavity of the actuating mechanism is overhigh, the hydraulic oil can flow into the low-pressure cavity of the actuating mechanism through the overflow valve, so that the effect of protecting the hydraulic elements is achieved.
8. Two-position two-way electromagnetic directional valves are connected in series on the oil inlet path and the oil return path of the left walking motor and the right walking motor, so that the rotary drill can realize the steering function without additionally arranging a steering mechanism.
9. The hydraulic circuit adopts a volume speed regulation mode, controls the movement speed of each actuating element by changing the displacement of a left variable pump and a right variable pump, has no throttling loss and overflow loss, and can change the working pressure of the system along with the load by adopting the volume speed regulation, so the adaptability of the load is better and the efficiency is high.
Drawings
Fig. 1 is a schematic structural diagram of the present invention;
description of reference numerals: 1-left walking motor, 2-rotary motor, 3-pressurizing hydraulic cylinder, 4-right walking motor, 5-walking oil-supplementing check valve, 6-walking buffer overflow valve, 7-pressure valve bank, 8-two-position two-way electromagnetic reversing valve, 9-rotary oil-supplementing check valve, 10-rotary buffer overflow valve, 11-one-way sequence valve, 12-pressurizing buffer overflow valve, 13-pressurizing oil-supplementing check valve, 14-first two-position three-way hydraulic control reversing valve, 15-second two-position three-way hydraulic control reversing valve, 16-third two-position three-way hydraulic control reversing valve, 17-fourth two-position three-way reversing valve, 18-left cleaning valve bank, 19-right cleaning valve bank, 20-four-position four-way manual reversing valve, 21-left variable pump, 22-right variable pump, 23-quantitative pump, 24-filter.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings and examples.
The embodiment of the utility model provides a: the structure schematic diagram of the closed hydraulic circuit of the rotary drilling rig is shown in figure 1, and the closed hydraulic circuit comprises a left oil supply circuit and a right oil supply circuit, wherein the left oil supply circuit and the right oil supply circuit are both connected with a constant delivery pump 23, the constant delivery pump 23 is connected with an oil tank, a left walking motor 1 and a rotary motor 2 are connected in parallel on the left oil supply circuit, and a right walking motor 4 and a pressurizing hydraulic cylinder 3 are connected in parallel on the right oil supply circuit; the left oil supply loop comprises a left variable pump 21, a first two-position three-way hydraulic control reversing valve 14 and a second two-position three-way hydraulic control reversing valve 15, wherein the first two-position three-way hydraulic control reversing valve 14 and the second two-position three-way hydraulic control reversing valve 15 are respectively arranged at an oil outlet end and an oil return end of the left variable pump 21; the right oil supply loop comprises a right variable pump 22, and a third two-position three-way hydraulic control reversing valve 16 and a fourth two-position three-way hydraulic control reversing valve 17 which are respectively arranged at an oil outlet end and an oil return end of the right variable pump 22, wherein the oil inlet end and the oil return end of the right traveling motor 4 are respectively connected to one through end of the third two-position three-way hydraulic control reversing valve 16 and the fourth two-position three-way hydraulic control reversing valve 17, and the oil inlet end and the oil return end of the pressurizing hydraulic cylinder 3 are respectively connected to the other through end of the third two-position three-way hydraulic control reversing valve 16 and the fourth two-position three-way hydraulic control reversing valve 17; the first two-position three-way hydraulic control reversing valve 14, the second two-position three-way hydraulic control reversing valve 15, the third two-position three-way hydraulic control reversing valve 16 and the fourth two-position three-way hydraulic control reversing valve 17 are all connected with the oil outlet end of the four-position four-way manual reversing valve 20 in parallel, and the oil inlet end of the four-position four-way manual reversing valve 20 is connected with the dosing pump 23.
Further, a left cleaning valve group 18 and a right cleaning valve 19 are respectively connected in parallel on the left oil supply loop and the right oil supply loop.
Further, a filter 24 is installed on the oil inlet end of the fixed displacement pump 23.
Further, a traveling oil supplementing check valve 5 and a traveling buffer overflow valve 6 are connected in series to the oil inlet end and the oil return end of the left traveling motor 1 and the right rotary motor 4, and a pressure valve bank 7 and a two-position two-way electromagnetic directional valve 8 are connected in parallel between the oil inlet end and the oil return end of the left traveling motor 1 and the right rotary motor 4.
Furthermore, two rotary oil-supplementing one-way valves 9 and two rotary buffer overflow valves 10 are connected in parallel between the oil inlet end and the oil return end of the rotary motor 2.
Further, the oil inlet end and the oil return end of the pressurizing hydraulic cylinder 3 are both connected in series with a one-way sequence valve 11, and meanwhile, two pressurizing oil-supplementing one-way valves 13 and two pressurizing buffer overflow valves 12 are connected in parallel between the oil inlet end and the oil return end of the pressurizing hydraulic cylinder 3.
The utility model discloses a theory of operation:
the utility model discloses a four-bit four-way manual reversing valve 20 and four two tee bend liquid accuse switching-over valves realize that the rig does not drill when the walking, the operating condition of walking not in drilling, the concrete implementation process as follows:
when the rotary drill rig travels, hydraulic oil flows into the four-position four-way manual reversing valve 20 through the metering pump 23, the hydraulic oil enters the control oil path through the right position of the four-position four-way manual reversing valve 20, the first two-position three-way hydraulic control reversing valve 14, the second two-position three-way hydraulic control reversing valve 15, the third two-position three-way hydraulic control reversing valve 16 and the fourth two-position three-way hydraulic control reversing valve 17 are all in the right position state, the left variable pump 21 and the right variable pump 22 are respectively connected with the left traveling loop and the right traveling loop, the left traveling motor 1 and the right traveling motor 4 are operated, the starting and stopping of the left and right rotary motors can be controlled by controlling the left and right positions of the two-position two-way electromagnetic reversing valve 8 in the traveling loops, and the steering of the rotary drill rig is achieved.
A walking oil supplementing one-way valve 5, a walking buffer overflow valve 6 and a pressure valve group 7 are arranged in the left walking loop and the right walking loop to form walking buffer loops; when the walking motor works normally, hydraulic oil enters the walking motor through the check valve in the pressure valve group 7, and then the pressure valve in the pressure valve group 7 is opened to return to the oil tank. When the speed of the walking motor of the roller-bit drilling machine exceeds the limit value, insufficient oil supply of hydraulic oil in the system can be caused, so that the pressure in an oil way is reduced, then the valve core of the pressure valve in the pressure valve group 7 is pushed to move right by the elastic force of the spring, the oil port channel of the pressure valve in the pressure valve group 7 is closed or reduced, the speed of the walking motor is reduced or braked, and the drilling machine is prevented from being damaged due to downhill or sudden braking.
When the roller-bit drilling machine drills, hydraulic oil flows into the four-position four-way manual reversing valve 20 through the metering pump 23, the hydraulic oil enters the control oil path through the left position of the four-position four-way manual reversing valve 20, the first two-position three-way hydraulic control reversing valve 14, the second two-position three-way hydraulic control reversing valve 15, the third two-position three-way hydraulic control reversing valve 16 and the fourth two-position three-way hydraulic control reversing valve 17 are all in the left position state, the left variable pump 21 and the right variable pump 22 are connected with the rotary loop and the pressurizing loop respectively, and therefore the rotary motor 2 and the pressurizing hydraulic cylinder 3 work.
A rotary oil-supplementing check valve 9 and a rotary buffering overflow valve 10 in the rotary loop form a buffering loop, wherein the rotary buffering overflow valve 10 is respectively communicated with a high-pressure oil port and a low-pressure oil port. When the rotary motor stops or brakes, hydraulic oil in the high-pressure oil chamber enters the low-pressure oil chamber of the system through the rotary buffering overflow valve 10, so that hydraulic impact force on the system during braking can be reduced, and vibration and damage to hydraulic elements during working can be effectively reduced. The one-way sequence valve 11 in the pressurizing loop forms a balance loop, when the pressurizing hydraulic cylinder 3 does not work, the one-way sequence valve 11 is closed, and the roller bit cannot automatically slide downwards. When the pressurizing hydraulic cylinder 3 pressurizes downwards, the pressure of the rod cavity is increased to exceed the set pressure of the one-way sequence valve 11, and the one-way sequence valve 11 is opened, so that the gravity of the roller bit can be balanced, and the phenomenon of overspeed cannot occur. When the walking or drilling speed of the roller-bit drill needs to be changed, the displacement of the left variable pump 21 and the right variable pump 22 is changed.
When the working time of the closed hydraulic circuit is too long, the temperature of hydraulic oil in the circuit continuously rises due to the fact that the hydraulic oil cannot return to the oil tank, so that the hydraulic oil reaches the opening pressure of the left cleaning valve group 18 and the right cleaning valve group 19, high-temperature hydraulic oil returns to the oil tank through the left cleaning valve group 18 and the right cleaning valve group 19, meanwhile, the constant delivery pump 23 continuously supplies oil which is not polluted by high temperature to the circuit, and the purpose of heat dissipation of the closed hydraulic oil is achieved.
Claims (6)
1. The utility model provides a rotary drill's closed hydraulic circuit, includes left oil feed return circuit and right oil feed return circuit, its characterized in that: the left oil supply loop and the right oil supply loop are both connected with a constant delivery pump (23), the constant delivery pump (23) is connected with an oil tank, a left walking motor (1) and a rotary motor (2) are connected in parallel on the left oil supply loop, and a right walking motor (4) and a pressurizing hydraulic cylinder (3) are connected in parallel on the right oil supply loop; the left oil supply loop comprises a left variable pump (21), a first two-position three-way hydraulic control reversing valve (14) and a second two-position three-way hydraulic control reversing valve (15), wherein the first two-position three-way hydraulic control reversing valve (14) and the second two-position three-way hydraulic control reversing valve (15) are respectively arranged at the oil outlet end and the oil return end of the left variable pump (21), the oil inlet end and the oil return end of the left walking motor (1) are respectively connected to one of the through ends of the first two-position three-way hydraulic control reversing valve (14) and the second two-position three-way hydraulic control reversing valve (15), and the oil inlet end and the oil return end of the rotary motor (2) are respectively connected to the other through ends of the first two-position three-way; the right oil supply loop comprises a right variable pump (22), and a third two-position three-way hydraulic control reversing valve (16) and a fourth two-position three-way hydraulic control reversing valve (17) which are respectively arranged at an oil outlet end and an oil return end of the right variable pump (22), the oil inlet end and the oil return end of the right walking motor (4) are respectively connected to one of the through ends of the third two-position three-way hydraulic control reversing valve (16) and the fourth two-position three-way hydraulic control reversing valve (17), and the oil inlet end and the oil return end of the pressurizing hydraulic cylinder (3) are respectively connected to the other through end of the third two-position three-way hydraulic control reversing valve (16) and the other through end of the fourth two-position three-way hydraulic control reversing valve (17; the first two-position three-way hydraulic control reversing valve (14), the second two-position three-way hydraulic control reversing valve (15), the third two-position three-way hydraulic control reversing valve (16) and the fourth two-position three-way hydraulic control reversing valve (17) are all connected with the oil outlet end of the four-position four-way manual reversing valve (20) in parallel, and the oil inlet end of the four-position four-way manual reversing valve (20) is connected with the dosing pump (23).
2. The closed hydraulic circuit of a roller cone drilling machine according to claim 1, characterized in that: and the left oil supply loop and the right oil supply loop are respectively connected with a left cleaning valve group (18) and a right cleaning valve (19) in parallel.
3. The closed hydraulic circuit of a roller cone drilling machine according to claim 1, characterized in that: and a filter (24) is arranged at the oil inlet end of the fixed displacement pump (23).
4. The closed hydraulic circuit of a roller cone drilling machine according to claim 1, characterized in that: the oil inlet end and the oil return end of the left walking motor (1) and the right walking motor (4) are all connected in series with a walking oil supplementing one-way valve (5) and a walking buffer overflow valve (6), and meanwhile, a pressure valve bank (7) and a two-position two-way electromagnetic reversing valve (8) are connected in parallel between the oil inlet end and the oil return end of the left walking motor (1) and the right walking motor (4).
5. The closed hydraulic circuit of a roller cone drilling machine according to claim 1, characterized in that: two rotary oil-supplementing one-way valves (9) and two rotary buffer overflow valves (10) are connected in parallel between the oil inlet end and the oil return end of the rotary motor (2).
6. The closed hydraulic circuit of a roller cone drilling machine according to claim 1, characterized in that: the oil inlet end and the oil return end of the pressurizing hydraulic cylinder (3) are both connected in series with a one-way sequence valve (11), and meanwhile, two pressurizing oil-supplementing one-way valves (13) and two pressurizing buffer overflow valves (12) are connected in parallel between the oil inlet end and the oil return end of the pressurizing hydraulic cylinder (3).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020919019.7U CN212536317U (en) | 2020-05-27 | 2020-05-27 | Closed hydraulic circuit of rotary drill |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020919019.7U CN212536317U (en) | 2020-05-27 | 2020-05-27 | Closed hydraulic circuit of rotary drill |
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| Publication Number | Publication Date |
|---|---|
| CN212536317U true CN212536317U (en) | 2021-02-12 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202020919019.7U Active CN212536317U (en) | 2020-05-27 | 2020-05-27 | Closed hydraulic circuit of rotary drill |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212536317U (en) |
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2020
- 2020-05-27 CN CN202020919019.7U patent/CN212536317U/en active Active
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