Iron roughneck hydraulic system

Abstract

The present application relates to a kind of iron driller hydraulic systems, including hydraulic pump station, electromagnetic reversing valve group, pilot pressure reducing overflow valve, two parallelly arranged upper and lower off oil cylinder;The oil supply port and oil return port of hydraulic pump station are communicated with the corresponding oil port of electromagnetic reversing valve group one-to-one, and electromagnetic reversing valve group includes first working link, and first working link has first working oil port and second working oil port, first working oil port is communicated with the rodless cavity of two upper and lower off oil cylinder, the rod cavity of two upper and lower off oil cylinder is communicated with the B port of pilot pressure reducing overflow valve, the T port of pilot pressure reducing overflow valve is communicated with the oil tank of hydraulic pump station, and the A port of pilot pressure reducing overflow valve is communicated with second working oil port.Iron driller hydraulic system, by pilot pressure reducing overflow valve, realize that the screwing pressure reaches set pressure, carry out low pressure overflow, so that it can guarantee that screw is tightened, and can prevent screw damage.

Description

Technical Field

[0001] This invention relates to the field of iron drill technology, and more particularly to a hydraulic system for iron drills. Background Technology

[0002] During drilling operations, frequent threading and unthreading of drill pipes is required, and the quality of these operations directly impacts the drilling platform's performance. Currently, the main auxiliary threading and unthreading equipment used in China is either a hydraulic-pneumatic tong or a metal drill bit. Hydraulic-pneumatic tongs require changing the jaw plates for different pipe diameters, making the process cumbersome. Metal drill bits are suitable for connecting and disconnecting drill pipes and drill collars during drilling, with a clamping range of 89-150mm, and do not require jaw plate replacement.

[0003] Chinese patent document CN116220581 A discloses a metal drill bit, which includes a clamping and unhooking device, a rotating device, a horizontal driver, and a lifting driver. The clamping and unhooking device includes a lower clamp and an upper clamp. The upper clamp includes two upper clamping arms, an upper clamping drive cylinder, and an upper unhooking driver. The upper clamping drive cylinder is connected to the drive ends of the two upper clamping arms and is used to drive the drive ends of the two upper clamping arms to open or retract, thereby causing the clamping ends of the two upper clamping arms to retract or open. The upper unhooking driver is correspondingly connected to the two upper clamping arms and is used to drive the two upper clamping arms to rotate synchronously relative to the lower clamp to fasten or unhook. The defects and shortcomings of this iron drill are: (1) When the upper and lower clamping drive reaches the set pressure during the upper and lower clamping, it cannot release the pressure and continues to maintain the set pressure, which will damage the drill rod threads; (2) When the drill rod is screwed, the lower clamp and the screwing device are clamped, and the upper clamp needs to be opened, that is, the upper clamping drive cylinder retracts and drives the clamping ends of the two upper clamping arms to open. During this process, due to the excessive opening angle of the two upper clamping arms, the opening / closing time of the upper clamp during upper clamping or unclamping is long and the efficiency is low. Summary of the Invention

[0004] (a) Technical problems to be solved

[0005] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a hydraulic system for iron drills, which solves the technical problem that the existing iron drills cannot release pressure after the upper threading pressure reaches the set value, and will continue to be threaded under high pressure, resulting in damage to the drill rod threads.

[0006] (II) Technical Solution

[0007] To achieve the above objectives, the main technical solutions adopted by the present invention include:

[0008] This invention provides a hydraulic system for a steel drill, including a hydraulic pump station, an electromagnetic directional valve group, a pilot pressure reducing relief valve, and an actuator. The actuator includes two parallel-connected upper and lower uncoupling cylinders.

[0009] The oil supply port and return port of the hydraulic pump station are connected one-to-one with the corresponding oil ports of the electromagnetic directional valve group. The electromagnetic directional valve group includes a first working link, which has a first working oil port and a second working oil port. The first working oil port is connected to the rodless chamber of the two upper and lower release cylinders. The rod chamber of the two upper and lower release cylinders is connected to the B port of the pilot pressure reducing relief valve. The T port of the pilot pressure reducing relief valve is connected to the oil tank of the hydraulic pump station. The A port of the pilot pressure reducing relief valve is connected to the second working oil port.

[0010] Optionally, the pilot-operated pressure-reducing relief valve includes a first check valve, a pressure-reducing relief valve, a pilot-operated relief valve, and a two-position two-way solenoid directional valve.

[0011] A first check valve and a pressure-reducing relief valve are connected in parallel between ports A and B. The first check valve is unidirectionally open from port B to port A. The inlet and outlet of the pressure-reducing relief valve are connected to ports A and B respectively. The control port of the pressure-reducing relief valve is connected to the inlet of the pilot relief valve and the two-position two-way solenoid directional valve. The drain port of the pressure-reducing relief valve, the outlet of the pilot relief valve, and the outlet of the two-position two-way solenoid directional valve are all connected to port T.

[0012] Optionally, the iron drill hydraulic system also includes a first two-way hydraulic lock and a second two-way hydraulic lock, and the actuator also includes an upper clamping cylinder and a lower clamping cylinder;

[0013] The electromagnetic directional valve assembly also includes a second working link, which has a third working port and a fourth working port. The third working port is connected to the rod chambers of the upper clamping cylinder and the lower clamping cylinder, respectively, and the fourth working port is connected to the rodless chambers of the upper clamping cylinder and the lower clamping cylinder, respectively. A first bidirectional hydraulic lock is provided between the upper clamping cylinder and the second working link to control the upper clamping cylinder to remain stationary under load. A second bidirectional hydraulic lock is provided between the lower clamping cylinder and the second working link to control the lower clamping cylinder to remain stationary under load.

[0014] Optionally, the Iron Drill hydraulic system also includes an oil reservoir, a one-way throttle valve, a first hydraulically controlled check valve, a second check valve, and a third check valve;

[0015] The electromagnetic reversing valve assembly also includes a third working link, which has a fifth working port. The fifth working port is connected to the rod chamber of the upper clamping cylinder, the rod chamber of the reservoir is connected to the rodless chamber of the upper clamping cylinder, the rodless chamber of the reservoir is connected to the first port of the one-way throttle valve, and the second port of the one-way throttle valve is divided into two branches. One branch is connected to the first port of the first hydraulic check valve, the second port of the first hydraulic check valve is connected to the oil tank, and the other branch is connected to the fourth working port.

[0016] The control port of the first hydraulic check valve is connected to the fifth working port. The second check valve is located between the fifth working port and the rod chamber of the upper clamping cylinder and is unidirectionally open from the fifth working port to the rod chamber of the upper clamping cylinder. The third check valve is located between the fourth working port and the second port of the one-way throttle valve and is unidirectionally open from the fourth working port to the second port of the one-way throttle valve.

[0017] Optionally, the iron drill hydraulic system also includes an electro-proportional multi-way valve arranged in parallel with the solenoid directional valve group, and the actuator also includes two rotary clamping cylinders in parallel and four rotary motors in parallel.

[0018] The electromagnetic reversing valve assembly includes a fourth working link, which has a sixth working port and a seventh working port. The sixth working port is connected to the rodless chamber of the two rotary clamping cylinders, and the seventh working port is connected to the rod chamber of the two rotary clamping cylinders.

[0019] The oil supply port and return port of the hydraulic pump station are connected one-to-one with the corresponding oil ports of the electro-proportional multi-way valve. The electro-proportional multi-way valve has a fifth working link, which is connected to each rotary motor. This allows the hydraulic oil output from the hydraulic pump station to enter each rotary motor after being regulated by the fifth working link, so as to control the speed of each rotary motor.

[0020] Optionally, the fifth working link has an eighth working port and a ninth working port. A two-stage flow divider and combiner valve is provided between the eighth working port and the first port of the four rotary motors. The second port of the four rotary motors is connected to the ninth working port.

[0021] Optionally, the actuator may also include a lifting cylinder;

[0022] The electro-proportional multi-way valve has a sixth working link, which has a tenth working port and an eleventh working port. The tenth working port is connected to the rodless chamber of the lifting cylinder, and the eleventh working port is connected to the rod chamber of the lifting cylinder.

[0023] Optionally, the actuator also includes two parallel telescopic cylinders;

[0024] The electro-proportional multi-way valve has a seventh working link, which has a twelfth working port and a thirteenth working port. The twelfth working port is connected to the rod chamber of the two telescopic cylinders, and the thirteenth working port is connected to the rodless chamber of the two telescopic cylinders.

[0025] Optionally, the hydraulic pump station also includes a constant pressure variable pump, which is equipped with a motor. The oil outlet of the oil tank is connected to the oil inlet of the constant pressure variable pump. The oil outlet of the constant pressure variable pump is connected to a main oil supply line, which is divided into two lines. One line is connected to the oil inlet of the solenoid directional valve group, and the other line is connected to the oil inlet of the electro-proportional multi-way valve.

[0026] The oil tank's return port is connected to the main return oil pipeline, which is divided into two lines. One line is connected to the oil outlet of the solenoid directional valve assembly, and the other line is connected to the oil outlet of the electro-proportional multi-way valve.

[0027] Optionally, a pilot control on / off valve is also installed on the main oil supply line. The pilot control on / off valve includes a hydraulic on / off valve and a two-position two-way solenoid directional valve.

[0028] The inlet of the hydraulic on / off valve is connected to the outlet of the constant pressure variable pump, the outlet of the hydraulic on / off valve is connected to the main oil supply line, the pilot control port of the hydraulic on / off valve is connected to the inlet of the second two-position two-way solenoid directional valve, and the outlet of the second two-position two-way solenoid directional valve is connected to the main return line.

[0029] (III) Beneficial Effects

[0030] The beneficial effects of this invention are as follows: The hydraulic system for iron drills of this invention includes a hydraulic pump station, an electromagnetic directional valve group, a pilot pressure reducing relief valve, and an actuator. The actuator includes two parallel-connected upper and lower release cylinders. The oil supply port and return port of the hydraulic pump station are connected one-to-one with the corresponding oil ports of the electromagnetic directional valve group. The electromagnetic directional valve group includes a first working link, which has a first working oil port and a second working oil port. The first working oil port is connected to the rodless chamber of the two upper and lower release cylinders. The rod chamber of the cylinder is connected to port B of the pilot pressure reducing relief valve, port T of the pilot pressure reducing relief valve is connected to the oil tank of the hydraulic pump station, and port A of the pilot pressure reducing relief valve is connected to the second working oil port. Compared with the prior art, the hydraulic system of the present invention ensures that the upper and lower threads of the upper and lower threads are tightened according to the preset value through the pilot pressure reducing relief valve. When the upper and lower threads pressure exceeds the preset value, the pressure is automatically reduced and unloaded. Thus, when the upper and lower threads of the upper and lower threads retract and tighten, it can ensure that the drill rod threads are tightened and prevent damage to the drill rod threads. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the hydraulic system for iron drillers of the present invention;

[0032] Figure 2 for Figure 1 An enlarged schematic diagram of the hydraulic system of the iron driller at the electromagnetic reversing valve assembly;

[0033] Figure 3 This is a schematic diagram of the structure of Embodiment 2 of the hydraulic system for iron drillers of the present invention.

[0034] [Explanation of Labels in the Attached Image]

[0035] 1: Oil tank; 2: Motor; 3: Constant pressure variable pump; 4: Pilot control on / off valve; 5: Hydraulic control on / off valve; 6: Two-position two-way solenoid directional valve II; 7: Electro-proportional multi-way valve; 8: Solenoid directional valve assembly; 9: Lifting cylinder; 10: Telescopic cylinder; 11: Rotary motor; 12: Rotary clamping cylinder; 13: Upper clamping cylinder; 14: Lower clamping cylinder; 15: Upper uncoupling cylinder; 16: Oil reservoir; 17: Pilot pressure reducing relief valve; 18: First check valve; 19: Pressure reducing relief valve. Flow valve; 20: Pilot relief valve; 21: Two-position two-way solenoid directional valve; 23: First two-way hydraulic lock; 24: Second two-way hydraulic lock; 25: One-way throttle valve; 26: First hydraulically controlled check valve; 27: Second check valve; 28: Third check valve; 29: First limit switch; 30: Second limit switch; 31: First position proximity switch; 32: Third limit switch; 33: Secondary flow divider / combiner valve; 34: Second position proximity switch; 35: Fourth limit switch. Detailed Implementation

[0036] To better explain and facilitate understanding of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] Example 1:

[0038] Reference Figure 1 and Figure 2 This embodiment provides a hydraulic system for a steel drill, including a hydraulic pump station, an actuator, an electromagnetic directional valve group 8, and an electro-proportional multi-way valve 7 connected in parallel with the electromagnetic directional valve group 8. The actuator includes a lifting cylinder 9, a telescopic cylinder 10, a rotary lever motor 11, a rotary lever clamping cylinder 12, an upper clamping cylinder 13, a lower clamping cylinder 14, and an upper uncoupling cylinder 15.

[0039] The oil supply and return ports of the hydraulic pump station are connected one-to-one with the corresponding ports of the electromagnetic directional valve assembly 8. The electromagnetic directional valve assembly 8 includes multiple working links, each of which is connected one-to-one with the upper clamping cylinder 13, lower clamping cylinder 14, upper uncoupling cylinder 15, and rotary clamping cylinder 12 to control the extension or retraction of each cylinder. It should be noted that the upper clamping cylinder 13 is the drive cylinder for the upper clamp, used to drive the two upper clamping arms of the upper clamp to retract or open. The upper uncoupling cylinder 15 is the rotation drive for the upper clamp, used to drive the two upper clamping arms of the upper clamp to rotate synchronously relative to the lower clamp to perform upper or lower coupling. The lower clamping cylinder 14 is the drive cylinder for the lower clamp, used to drive the two lower clamping arms of the lower clamp to retract or open. The rotary clamping cylinder 12 is the opening and closing drive for the rotary coupling device, used to drive the two rotary coupling arms of the rotary coupling device to clamp or release the upper drill pipe.

[0040] The oil supply and return ports of the hydraulic pump station are connected one-to-one with the corresponding ports of the electro-proportional multi-way valve 7. The electro-proportional multi-way valve 7 includes multiple working links, each of which is connected one-to-one with the lifting cylinder 9, the telescopic cylinder 10, and the rotary motor 11. This allows the hydraulic oil output from the hydraulic pump station to enter the lifting cylinder 9, the telescopic cylinder 10, and the rotary motor 11 after being regulated by the corresponding working links of the electro-proportional multi-way valve 7, thereby controlling the operating speed of the lifting cylinder 9 and the telescopic cylinder 10, as well as the rotation speed of the motor. It should be noted that the rotary motor 11 is the rotary drive component of the rotary device, used to drive the upper drill rod to rotate relative to the lower drill rod, so as to screw in or out the drill rod connection thread. The lifting cylinder 9 is the drive cylinder of the lifting actuator, used to drive the jaw device to move up and down. The telescopic cylinder 10 is the drive cylinder of the horizontal actuator, used to drive the jaw device to move horizontally. The jaw device includes a clamping and uncoupling device and a rotary device.

[0041] The hydraulic system for the iron drill in this embodiment includes a pilot pressure reducing relief valve 17. The electromagnetic directional valve group 8 includes a first working link, which has a first working port and a second working port. There are two upper and lower release cylinders 15. The first working port is connected to the rodless chamber of the two upper and lower release cylinders 15, and the rod chamber of the two upper and lower release cylinders 15 is connected to the B port of the pilot pressure reducing relief valve 17. The T port of the pilot pressure reducing relief valve 17 is connected to the oil tank 1 of the hydraulic pump station, and the A port of the pilot pressure reducing relief valve 17 is connected to the second working port.

[0042] In this embodiment of the hydraulic system for iron drills, a pilot pressure reducing relief valve 17 is installed between the electromagnetic reversing valve group 8 and the rod chambers of the two upper uncoupling cylinders 15. The pilot pressure reducing relief valve 17 is a hydraulic valve with dual functions of pressure reduction and relief. It can automatically overflow after the upper uncoupling pressure reaches a preset value to release excess pressure. As a result, when the upper uncoupling cylinder 15 retracts to upper uncoupling, it can ensure that the drill rod threads are tightened and prevent damage to the drill rod threads.

[0043] Specifically, the pilot pressure reducing relief valve 17 includes a first check valve 18, a pressure reducing relief valve 19, a pilot relief valve 20, and a two-position two-way solenoid directional valve 21.

[0044] A first check valve 18 and a pressure-reducing relief valve 19 are connected in parallel between ports A and B. The first check valve 18 is unidirectionally open from port B to port A. The inlet and outlet of the pressure-reducing relief valve 19 are connected to ports A and B respectively. The control port of the pressure-reducing relief valve 19 is connected to the inlet of the pilot relief valve 20 and the two-position two-way solenoid directional valve 21 respectively. The drain port of the pressure-reducing relief valve 19, the outlet of the pilot relief valve 20, and the outlet of the two-position two-way solenoid directional valve 21 are all connected to port T.

[0045] The working principle of the pilot pressure reducing relief valve 17 in this embodiment is as follows: Before the drill pipe threading pressure reaches the set value, this valve group is used as a high-pressure pressure reducing valve, that is, the two-position two-way solenoid directional valve 21 is de-energized and closed, and the pilot relief valve 20 sets the pressure of the pressure reducing relief valve 19, which is the threading pressure set value. The handwheel of the pilot relief valve 20 is located on the control panel and can automatically adjust the threading pressure online in real time. When the threading pressure reaches the set value, the pressure sensor of the threading oil circuit sends a signal to control the two-position two-way solenoid directional valve 21 to be energized and opened. The control port of the pressure reducing relief valve 19 is directly connected to the oil tank 1, which makes the pressure at the control port of the pressure reducing relief valve 19 almost zero. At this time, the valve group is used as a low-pressure relief valve. The drain port of the pressure reducing relief valve 19 allows the high-pressure oil in the threading circuit to be unloaded and returned to the oil tank 1 under low pressure, thereby protecting the drill pipe threads from damage. It should be noted that the pressure sensor of the upper oil circuit can be set at port B to control the two-position two-way solenoid directional valve 21 to be de-energized or energized.

[0046] In this embodiment, the hydraulic system of the iron drill also includes a first bidirectional hydraulic lock 23 and a second bidirectional hydraulic lock 24. The electromagnetic reversing valve assembly 8 includes a second working link, which has a third working port and a fourth working port. The third working port is connected to the rod chambers of the upper clamping cylinder 13 and the lower clamping cylinder 14, respectively, and the fourth working port is connected to the rodless chambers of the upper clamping cylinder 13 and the lower clamping cylinder 14, respectively. The first bidirectional hydraulic lock 23 is provided between the upper clamping cylinder 13 and the second working link to control the upper clamping cylinder 13 to remain stationary under load. The second bidirectional hydraulic lock 24 is provided between the lower clamping cylinder 14 and the second working link to control the lower clamping cylinder 14 to remain stationary under load.

[0047] It should be noted that the bidirectional hydraulic lock consists of two hydraulically controlled check valves. These two check valves use the pressure from the other's oil circuit as pilot oil to open in reverse. When one circuit has no pressure, the other hydraulic lock closes in reverse. When the second working connection of the solenoid directional valve group 8 is in the neutral position, both the third and fourth working ports are connected to the oil tank 1. The first bidirectional hydraulic lock 23 and the second bidirectional hydraulic lock 24 close in reverse, locking the hydraulic oil in the two chambers of the upper clamping cylinder 13 and the lower clamping cylinder 14 respectively. This allows the upper clamping cylinder 13 and the lower clamping cylinder 14 to remain stationary for a relatively long time, thus forming a bidirectional hydraulic lock.

[0048] In this embodiment, the hydraulic system of the iron driller also includes an oil reservoir 16, a one-way throttle valve 25, a first hydraulically controlled one-way valve 26, a second one-way valve 27, and a third one-way valve 28.

[0049] The electromagnetic directional valve assembly 8 includes a third working link, which has a fifth working port. The fifth working port is connected to the rod chamber of the upper clamping cylinder 13, and the rod chamber of the reservoir cylinder 16 is connected to the rodless chamber of the upper clamping cylinder 13. The rodless chamber of the reservoir cylinder 16 is connected to the first port of the one-way throttle valve 25. The second port of the one-way throttle valve 25 is divided into two branches. One branch is connected to the first port of the first hydraulically controlled one-way valve 26, and the second port of the first hydraulically controlled one-way valve 26 is connected to the oil tank 1. The other branch is connected to the fourth working port.

[0050] The control port of the first hydraulic check valve 26 is connected to the fifth working port. The second check valve 27 is located between the fifth working port and the rod chamber of the upper clamping cylinder 13 and is unidirectionally open from the fifth working port to the rod chamber of the upper clamping cylinder 13. The third check valve 28 is located between the fourth working port and the inlet of the one-way throttle valve 25 and is unidirectionally open from the fourth working port to the inlet of the one-way throttle valve 25.

[0051] The function of the oil reservoir 16 is to reduce the opening angle of the two upper clamping arms by controlling the retraction amount of the upper clamping cylinder 13. Its working principle is as follows: When the drill pipe is screwed, the lower clamping arm and the screwing arm are clamped, and the upper clamping arm needs to be opened. At this time, the third working link is operated, and the fifth working oil port provides pressure oil. The pressure oil enters the rod chamber of the upper clamping cylinder 13 through the second one-way valve 27. Due to the locking of the first bidirectional hydraulic lock 23, the hydraulic oil in the rodless chamber of the upper clamping cylinder 13 flows to the rod chamber of the oil reservoir 16. The hydraulic oil in the rodless chamber of the oil reservoir 16 returns to the oil tank through the one-way throttle valve 25 and the first hydraulically controlled one-way valve 26 that opens in the opposite direction, so that the oil reservoir 16 retracts. During this process, the rod chamber volume of the oil reservoir 16 determines the retraction amount of the upper clamping cylinder 13, which in turn determines the opening angle of the upper clamping arm. When selecting the specifications of the oil reservoir 16, the rod chamber volume should be controlled within the range of the upper clamping slips allowing the drill rod to pass. At the same time, in order to ensure that the oil reservoir 16 can fully extend and reset before being clamped by the upper and lower clamps, the oil reservoir 16 should be selected with a larger cylinder diameter and a smaller rod diameter, or a cylinder seal with low frictional resistance should be selected to ensure that the oil reservoir 16 extends and resets first.

[0052] When the second working link is operated and the upper and lower clamping arms are driven to clamp, the fourth working port provides pressurized oil. The pressurized oil enters the rodless chamber of the reservoir cylinder 16 through the third one-way valve 28 and the one-way throttle valve 25. The hydraulic oil in the rod chamber of the reservoir cylinder 16 and the hydraulic oil coming out of the fourth working port are connected to the rodless chamber of the upper clamping cylinder 13, so that the piston rod of the reservoir cylinder 16 quickly extends and resets. At the same time, the upper clamping cylinder 13 and the lower clamping cylinder 14 also extend and clamp.

[0053] In this embodiment, the electromagnetic directional valve assembly 8 includes a fourth working link, which has a sixth working port and a seventh working port. The sixth working port is connected to the rodless chamber of the rotary clamping cylinder 12, and the seventh working port is connected to the rod chamber of the rotary clamping cylinder 12. The electro-proportional multi-way valve 7 has a fifth working link, which is connected to the rotary motor 11, so that the hydraulic oil output from the hydraulic pump station enters the rotary motor 11 after being regulated by the fifth working link, thereby controlling the speed of the rotary motor 11.

[0054] Furthermore, in this embodiment, there are two rotary clamping cylinders 12, and the two rotary clamping cylinders 12 are arranged in parallel. There are four rotary motors 11, and the four rotary motors 11 are arranged in parallel. The fifth working section has an eighth working port and a ninth working port. A two-stage diversion and combination valve 33 is provided between the eighth working port and the first port of the four rotary motors 11. The second port of the four rotary motors 11 is connected to the ninth working port.

[0055] It should be noted that the secondary flow divider / combiner valve 33 in this embodiment consists of three flow divider / combiner valves, having one inlet and four outlets. The hydraulic oil exiting the eighth working port enters the secondary flow divider / combiner valve 33, where it is first evenly divided into two parts by one of the flow divider / combiner valves, and then evenly divided into four parts by the other two flow divider / combiner valves. These four parts of hydraulic oil enter the four rotary motors 11 one-to-one, thereby achieving proportional speed control and synchronous rotation of the four rotary motors 11.

[0056] In this embodiment, the electro-proportional multi-way valve 7 has a sixth working link, which has a tenth working port and an eleventh working port. The tenth working port is connected to the rodless chamber of the lifting cylinder 9, and the eleventh working port is connected to the rod chamber of the lifting cylinder 9.

[0057] In this embodiment, the lifting circuit uses a constant pressure variable pump 3, an electro-proportional multi-way valve 7, and a limit switch to achieve closed-loop control. The operation of the lifting cylinder 9 is as follows: When the electro-proportional multi-way valve 7 is operated upwards, the lifting cylinder 9 extends, raising the drill bit. After contacting the first limit switch 29 at the first set height, the electro-proportional multi-way valve 7 is automatically closed, and the lifting cylinder stops extending. When the electro-proportional multi-way valve 7 is operated downwards, the lifting cylinder 9 retracts, lowering the drill bit. After contacting the second limit switch 30 at the second set height, the electro-proportional multi-way valve 7 is automatically closed, and the lifting cylinder stops retracting.

[0058] In this embodiment, there are two telescopic cylinders 10. The electro-proportional multi-way valve 7 has a seventh working link, which has a twelfth working port and a thirteenth working port. The twelfth working port is connected to the rod chamber of the two telescopic cylinders 10, and the thirteenth working port is connected to the rodless chamber of the two telescopic cylinders 10.

[0059] In this embodiment, the telescopic circuit uses a constant pressure variable pump 3, an electro-proportional multi-way valve 7, a position proximity switch, and a limit switch to achieve closed-loop control. The operation process of the telescopic cylinder 10 is as follows:

[0060] When the electro-proportional multi-way valve 7 is opened, the telescopic cylinder 10 extends, and the drill bit's tongs head moves forward. After touching the first position proximity switch 31, the opening of the electro-proportional multi-way valve 7 is automatically reduced, and the telescopic cylinder 10 decelerates and extends. Once it extends to the center of the drill rod in the main back tongs, it touches the third limit switch 32, at which point the electro-proportional multi-way valve 7 is automatically closed, and the telescopic cylinder 10 stops extending. When the telescopic cylinder 10 retracts in the opposite direction, it first retracts quickly, then decelerates after touching the second position proximity switch 34, and finally stops after touching the fourth limit switch 35.

[0061] Example 2:

[0062] See Figure 3 This embodiment provides another hydraulic system for iron drillers. Based on Embodiment 1, the hydraulic pump station in this embodiment specifically includes an oil tank 1 and a constant pressure variable pump 3. A motor 2 is installed on the constant pressure variable pump 3. The oil outlet of the oil tank 1 is connected to the oil inlet of the constant pressure variable pump 3. The oil outlet of the constant pressure variable pump 3 is connected to a main oil supply pipeline. The main oil supply pipeline is divided into two lines. One line is connected to the oil inlet of the solenoid directional valve group 8, and the other line is connected to the oil inlet of the electro-proportional multi-way valve 7.

[0063] The return port of oil tank 1 is connected to the main return oil pipeline, which is divided into two lines. One line is connected to the oil outlet of the solenoid directional valve group 8, and the other line is connected to the oil outlet of the electro-proportional multi-way valve 7.

[0064] The hydraulic system for the iron drill in this embodiment is driven by a motor 2. It consists of the motor 2, a constant-pressure variable pump 3, a parallel-connected electro-proportional multi-way valve 7, a solenoid directional valve assembly 8, and an actuator. The output flow of the hydraulic pump is matched with the flow required by the actuator, reducing system heat generation and achieving energy savings. Furthermore, the solenoid directional valve assembly 8 is less expensive than the electro-proportional multi-way valve 7. Using the solenoid directional valve assembly 8 to control the upper clamping cylinder 13, lower clamping cylinder 14, upper uncoupling cylinder 15, and rotary clamping cylinder 12 can reduce the overall cost of the iron drill hydraulic system.

[0065] In this embodiment, the hydraulic system of the iron drill also includes an electronic control unit and a handle. The electronic control unit is electrically connected to the electro-proportional multi-way valve 7 and the solenoid directional valve group 8, respectively, for remote control of the electro-proportional multi-way valve 7 and the solenoid directional valve group 8; the handle is mechanically connected to the electro-proportional multi-way valve 7 and the solenoid directional valve group 8, respectively, for emergency manual control of the electro-proportional multi-way valve 7 and the solenoid directional valve group 8.

[0066] Furthermore, a pilot control on / off valve 4 is also installed on the main oil supply line. The pilot control on / off valve 4 includes a two-position two-way solenoid directional valve 6 and a hydraulic control on / off valve 5. The oil inlet of the hydraulic control on / off valve 5 is connected to the oil outlet of the constant pressure variable pump 3, the oil outlet of the hydraulic control on / off valve 5 is connected to the main oil supply line, the pilot control oil port of the hydraulic control on / off valve 5 is connected to the oil inlet of the two-position two-way solenoid directional valve 6, and the oil outlet of the two-position two-way solenoid directional valve 6 is connected to the main return oil line.

[0067] The pilot control on / off valve 4 operates as follows: when the two-position two-way solenoid directional valve 6 is de-energized, the two-position two-way solenoid directional valve 6 closes, blocking the flow of hydraulic oil to the main return pipeline, and controlling the hydraulic on / off valve 5 to close.

[0068] When the two-position two-way solenoid directional valve 6 is energized, it opens, and the pilot control oil of the hydraulic control on-off valve 5 enters the main return pipeline through the two-position two-way solenoid directional valve 6. As a result, the valve core of the hydraulic control on-off valve 5 moves and switches to the open state. Only then will the hydraulic system of the drilling rig be activated. This can prevent the operator from accidentally touching the drilling rig button and causing misoperation when remotely operating other drilling operations, which improves equipment safety.

[0069] The remaining parts that are the same as in Example 1 will not be repeated here.

[0070] In the description of this invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0071] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0072] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that they are in indirect contact through an intermediate medium. Furthermore, "above," "over," or "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," or "beneath" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0073] In the description of this specification, the terms "one embodiment," "some embodiments," "embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0074] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make modifications, alterations, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A hydraulic system for iron drillers, characterized in that, It includes a hydraulic pump station, an electromagnetic reversing valve group (8), a pilot pressure reducing relief valve (17) and an actuator, the actuator including two parallel upper unscrewing cylinders (15); The oil supply port and oil return port of the hydraulic pump station are connected one-to-one with the corresponding oil ports of the electromagnetic directional valve group (8). The electromagnetic directional valve group (8) includes a first working link. The first working link has a first working oil port and a second working oil port. The first working oil port is connected to the rodless chamber of the two upper unscrew cylinders (15). The rod chamber of the two upper unscrew cylinders (15) is connected to the B port of the pilot pressure relief valve (17). The T port of the pilot pressure relief valve (17) is connected to the oil tank (1) of the hydraulic pump station. The A port of the pilot pressure relief valve (17) is connected to the second working oil port. The hydraulic system of the iron drill also includes a first two-way hydraulic lock (23) and a second two-way hydraulic lock (24), and the actuator also includes an upper clamping cylinder (13) and a lower clamping cylinder (14). The electromagnetic reversing valve assembly (8) also includes a second working link, which has a third working port and a fourth working port. The third working port is connected to the rod chambers of the upper clamping cylinder (13) and the lower clamping cylinder (14) respectively, and the fourth working port is connected to the rodless chambers of the upper clamping cylinder (13) and the lower clamping cylinder (14) respectively. A first bidirectional hydraulic lock (23) is provided between the upper clamping cylinder (13) and the second working link to control the upper clamping cylinder (13) to remain stationary under load. A second bidirectional hydraulic lock (24) is provided between the lower clamping cylinder (14) and the second working link to control the lower clamping cylinder (14) to remain stationary under load. The hydraulic system of the Iron Drill also includes an oil reservoir (16), a one-way throttle valve (25), a first hydraulically controlled check valve (26), a second check valve (27) and a third check valve (28). The electromagnetic reversing valve assembly (8) also includes a third working link, which has a fifth working port. The fifth working port is connected to the rod chamber of the upper clamping cylinder (13), the rod chamber of the oil reservoir (16) is connected to the rodless chamber of the upper clamping cylinder (13), the rodless chamber of the oil reservoir (16) is connected to the first port of the one-way throttle valve (25), and the second port of the one-way throttle valve (25) is divided into two branches. One branch is connected to the first port of the first hydraulic control one-way valve (26), the second port of the first hydraulic control one-way valve (26) is connected to the oil tank (1), and the other branch is connected to the fourth working port. The control port of the first hydraulic check valve (26) is connected to the fifth working port. The second check valve (27) is located between the fifth working port and the rod chamber of the upper clamping cylinder (13) and is unidirectionally open from the fifth working port to the rod chamber of the upper clamping cylinder (13). The third check valve (28) is located between the fourth working port and the second port of the one-way throttle valve (25) and is unidirectionally open from the fourth working port to the second port of the one-way throttle valve (25).

2. The hydraulic system for iron drillers as described in claim 1, characterized in that: The pilot pressure reducing relief valve (17) includes a first check valve (18), a pressure reducing relief valve (19), a pilot relief valve (20), and a two-position two-way solenoid directional valve (21). A first check valve (18) and a pressure-reducing relief valve (19) are connected in parallel between port A and port B. The first check valve (18) is unidirectionally open from port B to port A. The oil inlet and outlet of the pressure-reducing relief valve (19) are connected to ports A and B respectively. The control oil port of the pressure-reducing relief valve (19) is connected to the oil inlet of the pilot relief valve (20) and the two-position two-way solenoid directional valve (21). The oil drain port of the pressure-reducing relief valve (19), the oil outlet of the pilot relief valve (20) and the oil outlet of the two-position two-way solenoid directional valve (21) are all connected to port T.

3. The hydraulic system for iron drillers as described in claim 1, characterized in that: The hydraulic system of the iron drill also includes an electro-proportional multi-way valve (7) connected in parallel with the solenoid directional valve group (8), and the actuator also includes two rotary clamping cylinders (12) connected in parallel and four rotary motors (11) connected in parallel. The electromagnetic reversing valve assembly (8) includes a fourth working link, which has a sixth working port and a seventh working port. The sixth working port is connected to the rodless chamber of the two rotary clamping cylinders (12) respectively, and the seventh working port is connected to the rod chamber of the two rotary clamping cylinders (12) respectively. The oil supply port and oil return port of the hydraulic pump station are connected one-to-one with the corresponding oil ports of the electro-proportional multi-way valve (7). The electro-proportional multi-way valve (7) has a fifth working link, which is connected to each rotary motor (11) respectively, so that the hydraulic oil output by the hydraulic pump station enters each rotary motor (11) after being regulated by the fifth working link, so as to control the speed of each rotary motor (11).

4. The hydraulic system for iron drillers as described in claim 3, characterized in that: The fifth working section has an eighth working port and a ninth working port. A two-stage diversion and collection valve (33) is provided between the eighth working port and the first port of the four rotary motors (11). The second port of the four rotary motors (11) is connected to the ninth working port.

5. The hydraulic system for iron drillers as described in claim 3, characterized in that: The actuator also includes a lifting cylinder (9); The electro-proportional multi-way valve (7) has a sixth working link, which has a tenth working port and an eleventh working port. The tenth working port is connected to the rodless chamber of the lifting cylinder (9), and the eleventh working port is connected to the rod chamber of the lifting cylinder (9).

6. The hydraulic system for iron drillers as described in claim 3, characterized in that: The actuator also includes two parallel telescopic cylinders (10). The electro-proportional multi-way valve (7) has a seventh working link, which has a twelfth working port and a thirteenth working port. The twelfth working port is connected to the rod chamber of the two telescopic cylinders (10) respectively, and the thirteenth working port is connected to the rodless chamber of the two telescopic cylinders (10) respectively.

7. The hydraulic system for iron drillers as described in claim 3, characterized in that: The hydraulic pump station also includes a constant pressure variable pump (3), which is equipped with a motor (2). The oil outlet of the oil tank (1) is connected to the oil inlet of the constant pressure variable pump (3). The oil outlet of the constant pressure variable pump (3) is connected to the main oil supply pipeline. The main oil supply pipeline is divided into two lines. One line is connected to the oil inlet of the electromagnetic reversing valve group (8), and the other line is connected to the oil inlet of the electro-proportional multi-way valve (7). The oil return port of the oil tank (1) is connected to the main return oil pipeline. The main return oil pipeline is divided into two lines. One line is connected to the oil outlet of the electromagnetic reversing valve group (8), and the other line is connected to the oil outlet of the electro-proportional multi-way valve (7).

8. The hydraulic system for iron drillers as described in claim 7, characterized in that: The main oil supply line is also equipped with a pilot control on / off valve (4), which includes a hydraulic on / off valve (5) and a two-position two-way solenoid directional valve (6). The inlet of the hydraulic on / off valve (5) is connected to the outlet of the constant pressure variable pump (3), the outlet of the hydraulic on / off valve (5) is connected to the main oil supply line, the pilot control port of the hydraulic on / off valve (5) is connected to the inlet of the two-position two-way solenoid directional valve (6), and the outlet of the two-position two-way solenoid directional valve (6) is connected to the main return oil line.

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