Anti-skid hydraulic system for top clamp

Abstract

The present invention relates to the technical field of clamping of mining drills, and discloses an anti-skidding hydraulic system for a top clamp. The anti-skidding hydraulic system for a top clamp comprises a power head motor connected with a forward oil circuit and a reverse oil circuit, a rodless chamber of a first clamping oil cylinder connected with a first rodless chamber oil circuit, a rod chamber of a first clamping oil cylinder connected with a first rod chamber oil circuit, a first check valve is provided between the reverse oil circuit and the first rodless chamber oil circuit for connection, and the first check valve is used for supplying oil in the reverse oil circuit to flow unidirectionally to the first rodless chamber oil circuit. The problem of slippage of the existing top clamp when the drill rod is unhooked is solved.

Description

Technical Field

[0001] The invention relates to the technical field of clamping of mining drills, and in particular to an anti-skid hydraulic system for a top clamp. Background Art

[0002] The top clamp is a type of clamp commonly used in mining drilling rigs. The drill rod is clamped by two clamping cylinders symmetrically arranged on both sides. The clamping cylinders on both sides include a rod chamber and a rodless chamber, and usually the rod chambers on both sides are connected to the same oil inlet circuit, and the two rodless chambers are commonly connected to another oil supply circuit. The internal hydraulic pressure of the rod chamber and the rodless chamber is controlled by different oil circuits, so that when oil is passed to the rodless chamber, the telescopic rods in the clamping cylinders on both sides extend, and the top clamp clamps the drill rod; when oil is passed to the rod chamber, the telescopic rods in the clamping cylinders on both sides retract, and the top clamp releases the drill rod synchronously. It has the advantages of simple structure, reliable clamping, and easy maintenance. Therefore, it has been widely used in mining drilling equipment.

[0003] However, the existing top clamps have the phenomenon of slipping during use, especially during the unbuckling of the drilling rig. When the drill pipe is connected, the drill pipe threaded joint is only subject to very small resistance. At this time, the power head only needs to provide a very small rotational torque to complete the connection. Therefore, the top clamp only needs to provide a very small clamping force to ensure that the drill pipe it clamps does not slip during the connection. When the drill pipe is unbuckled, the torque of the thread at the drill pipe threaded joint must be overcome. At this time, the drill pipe threaded joint is drilled and twisted at the bottom of the hole. The torque required for unbuckling is much greater than the torque required for connection. The power head needs to provide a large reversal torque to complete the unbuckling. Correspondingly, the top clamp also needs to provide a large and stable clamping force to ensure that the drill pipe clamped does not rotate with the power head when the power head is reversed, that is, no slipping occurs. However, since the clamping cylinder inevitably leaks oil in actual use, the slippage phenomenon of the top clamp during the unbuckling of the drill pipe has always existed.

[0004] Based on this, in order to further improve the safety of mining drill rigs, how to ensure the clamping force of the top clamp when the drill rod is shackled is an urgent problem to be solved in the current research and development of mining drill rigs. Summary of the invention

[0005] The present invention is intended to provide a hydraulic system for preventing a top clamp from slipping, so as to solve the problem that the existing top clamp slips when a drill pipe is shackled.

[0006] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: an anti-skid hydraulic system for the top clamp, the power head motor is connected with a forward oil circuit and a reverse oil circuit, the rodless chamber of the first clamping cylinder is connected with the first rodless chamber oil circuit, the rod chamber of the first clamping cylinder is connected with the first rod chamber oil circuit, and a first one-way valve is provided between the reverse oil circuit and the first rodless chamber oil circuit for connection, and the first one-way valve is used to allow the oil in the reverse oil circuit to flow to the first rodless chamber oil circuit in one direction.

[0007] The beneficial effects of this solution are as follows: by connecting the reverse oil circuit of the power head motor and the rodless chamber oil circuit in the top clamp and setting a one-way valve at the same time, a hydraulic system for preventing the top clamp from slipping is formed in which reverse linkage boosting, forward rotation and single motion of the clamp do not affect each other. This solves the problem of slipping caused by the decrease in the clamping force of the top clamp due to leakage of the clamping cylinder and the hydraulic lock in the existing hydraulic system of the top clamp, thereby ensuring on-site construction safety and improving construction efficiency.

[0008] Preferably, it also includes a second clamping cylinder, the rodless chamber of the second clamping cylinder is connected to the second rodless chamber oil circuit, the rod chamber of the second clamping cylinder is connected to the second rodless chamber oil circuit, and a second one-way valve is provided between the reversing oil circuit and the second rodless chamber oil circuit for connection, and the second one-way valve is used to allow the oil in the reversing oil circuit to flow to the second rodless chamber oil circuit in one direction.

[0009] Preferably, the oil inlet end of the second one-way valve is communicated with the oil inlet end of the first one-way valve.

[0010] Preferably, the oil inlet valve opening pressures of the first one-way valve and the second one-way valve are both set to be higher than the oil return pressure in the reversing oil circuit.

[0011] The beneficial effect of this solution is as follows: the opening pressures of the first one-way valve and the second one-way valve are set to be higher than the return oil pressure in the reversing oil circuit, so as to ensure that the oil inlet valve of the one-way valve will not open when the return oil flows in the forward and reverse oil circuits of the power head motor, thereby preventing a part of the refluxed hydraulic oil from flowing to the first one-way valve and the second one-way valve respectively, thereby causing a certain influence on the top clamp that originally needs to remain in a loose state, thereby avoiding the impact of the operating safety and stability of the original system due to the setting of the branch oil circuit.

[0012] Preferably, it also includes a first hydraulic lock, which is connected to the first rodless chamber oil circuit and the first rod chamber oil circuit.

[0013] The beneficial effect of this solution is that when the top clamp is in a loosened state, the rod chamber in the first clamping cylinder is in a high-pressure state under the pressure-maintaining action of the first hydraulic lock, and the rodless chambers are in a return oil low-pressure chamber state. Therefore, even in the extreme case of failure of the first one-way valve, based on the pressure difference between the rod chamber and the rodless chamber, the loosened state of the top clamp can be ensured not to be affected, that is, a double insurance effect of loosening and maintaining the top clamp is formed, ensuring that the top clamp in the hydraulic system will not affect the normal drilling work and can ensure the safety of construction.

[0014] Preferably, it also includes a second hydraulic lock, which is connected to the second rodless chamber oil circuit and the second rod chamber oil circuit.

[0015] Preferably, the oil outlet of the first one-way valve is connected to the oil outlet of the rodless chamber of the first clamping cylinder connected to the first hydraulic lock.

[0016] Preferably, the oil outlet of the second one-way valve is connected to the oil outlet of the rodless chamber of the second clamping cylinder of the second hydraulic lock.

[0017] Preferably, the first rod chamber oil circuit and the first rodless chamber oil circuit are respectively connected to port A1 and port B1 to enable the entry of hydraulic oil; the second rod chamber oil circuit and the second rodless chamber oil circuit are respectively connected to port A2 and port B2 to enable the entry of hydraulic oil. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the hydraulic system in Embodiment 1 of the present invention;

[0019] Figure 2 is a three-dimensional diagram of the double clamp in Example 2 of the present invention;

[0020] Figure 3 A three-dimensional diagram of the base in Example 2 of the present invention;

[0021] Figure 4 A three-dimensional diagram of the swinging body in Example 2 of the present invention;

[0022] Figure 5 A three-dimensional diagram of the external slip in Example 2 of the present invention;

[0023] Figure 6 A three-dimensional diagram of the inner slip in Example 2 of the present invention;

[0024] Figure 7 Schematic diagram of the internal structure of the double clamp in Example 2 of the present invention;

[0025] Figure 8 A three-dimensional diagram of the outer guide sleeve in Example 2 of the present invention;

[0026] Fig. 9A three-dimensional diagram of the inner guide sleeve in Example 2 of the present invention;

[0027] Fig.10 It is a three-dimensional diagram of the semi-ring guide sleeve in Example 2 of the present invention. DETAILED DESCRIPTION

[0028] The following is further described in detail through specific implementation methods:

[0029] The figure marks in the drawings of the specification include: power head motor 1, forward oil circuit 11, reverse oil circuit 12, first clamping cylinder 2, first hydraulic lock 21, first rodless chamber oil circuit 22, first rod chamber oil circuit 23, second clamping cylinder 3, second hydraulic lock 31, second rodless chamber oil circuit 32, second rod chamber oil circuit 33, first one-way valve 4, second one-way valve 5, base 6, mounting plate 61, flip plate 62, front support plate 63, reinforcement plate 64, rear support plate 65, rear lining plate 66, rear side plate 67, rear cylinder mounting plate 68, front side plate 69, swing body 7, support plate 71, front cylinder mounting plate 72, front lining plate 73, swing ear seat 74, flip shaft seat 75, flip pin 76, swing cylinder 77, outer cava 8, inner cava 81, outer guide sleeve 9, inner guide sleeve 91, semi-ring guide sleeve 92.

[0030] Example 1

[0031] like Figure 1 The anti-skid hydraulic system for the top clamp shown in the figure connects the reversing oil circuit 12 in the existing power head motor 1 controlled by hydraulic oil in the drilling rig with the clamping oil circuit in the top clamp, and at the same time adds unidirectional control and pressure-maintaining control to the additional oil circuit, thereby forming a new anti-skid hydraulic system for the top clamp in which the power head reversal is linked to the pressurization and the power head forward rotation does not affect each other, thereby solving the problem of slipping of the existing top clamp when the power head is reversed to unfasten the drill pipe.

[0032] After further research on the causes of slippage of the existing top clamp, it was found that the clamping slippage that occurs when the drill rod is unhooked is generally caused by defects in the hydraulic system of the top clamp: the clamping cylinder connected to the top clamp clamps the drill rod by the piston rod under the action of hydraulic oil, and then reverses the unhooking through the power head motor 1. During this clamping period, the clamping cylinder will inevitably have different degrees of hydraulic oil leakage, and the leakage amount and speed of the hydraulic oil will gradually increase with the increase of use time. Therefore, in the process from clamping to reverse unhooking, the clamping force of the clamping cylinder will gradually decrease, resulting in slippage due to the decrease in the clamping force of the top clamp when unhooking the drill rod, and finally leading to unhooking failure, seriously affecting construction efficiency and site safety. In order to reduce the pressure relief of the clamping cylinder, a hydraulic lock will be installed on the oil line of the clamping cylinder to maintain pressure, but the hydraulic lock still has a certain amount of hydraulic oil leakage, resulting in the slippage phenomenon not being effectively improved.

[0033] Based on this, Figure 1 As shown, according to the hydraulically driven power head motor 1 in the existing drilling rig, the power head motor 1 is connected to the forward oil circuit 11 and the reverse oil circuit 12, and the forward oil circuit 11 and the reverse oil circuit 12 are respectively supplied with oil through the A port and the B port; when the forward oil circuit 11 supplies oil, the power head motor 1 rotates forward and drives the drill rod (i.e., the active drill rod) installed on the power head to rotate forward for drilling operations; when the reverse oil circuit 12 supplies oil, the power head motor 1 reverses and drives the active drill rod to reverse for shackle. The top clamp is connected to a group of oil cylinders symmetrically arranged on both sides to achieve top clamping; in this embodiment, there are two top clamps, namely the front top clamp and the rear top clamp, and correspondingly, there are two groups of oil cylinders, which are respectively recorded as the first clamping oil cylinder 2 and the second clamping oil cylinder 3 for ease of understanding, and the first clamping oil cylinder 2 is connected to the front top clamp, and the second clamping oil cylinder 3 is connected to the rear top clamp. By providing two front and rear top clamps, the front and rear parts of the front drill rod in the drilling rig (specifically, the first drill rod exposed from the drill hole in this embodiment) are clamped to meet different construction requirements.

[0034] The two symmetrically arranged rodless chambers in the first clamping oil cylinder 2 are connected to the same first rodless chamber oil circuit 22. When the first rodless chamber oil circuit 22 is energized, the internal pressure of the two rodless chambers increases, pushing the piston rods in the two oil cylinders closer to each other to achieve the clamping operation of the front top clamp; the two rod chambers in the first clamping oil cylinder 2 are connected to the same first rod chamber oil circuit 23. When the first rod chamber oil circuit 23 is energized, the internal pressure of the two rod chambers in the first clamping oil cylinder 2 increases, and the two piston rods move away from each other to achieve the loosening operation of the front top clamp. An additional connecting oil circuit is provided between the reversing oil circuit 12 and the first rodless chamber oil circuit 22, and a first one-way valve 4 is provided on the connecting oil circuit. The oil inlet of the first one-way valve 4 is connected to the reversing oil circuit 12, that is, the first one-way valve 4 only allows the hydraulic oil in the reversing oil circuit 12 to flow into the first rodless chamber oil circuit 22 in one direction.

[0035] When the drill pipe is unhooked, the power head reverses, and the reversing oil circuit 12 in the power head motor 1 is connected to the oil. At this time, a part of the hydraulic oil flows to the two rodless chambers in the first clamping oil cylinder 2 through the first non-return valve 4, and the hydraulic oil of the leaking first clamping oil cylinder 2 is compensated, thereby improving the clamping strength of the front top clamp and preventing the occurrence of slippage. The hydraulic oil in the reversing oil circuit 12 is directly used to replenish the hydraulic oil during the clamping operation of the first clamping oil cylinder 2 without adding a new oil supply inlet, which reduces the complexity of the system and the cost of transformation, and can further ensure the timeliness and synchronization of the replenishment of the hydraulic oil in the rodless chamber of the first clamping oil cylinder 2. When the unbuckling is completed, the reversing operation of the power head stops, and the oil supply to the reversing oil circuit 12 is suspended, the replenishment of the hydraulic oil in the rodless chamber in the first clamping cylinder 2 can also be suspended synchronously. At this time, even if the pressure in the first rodless chamber oil circuit 22 is greater than the pressure in the reversing oil circuit 12, under the reverse cut-off protection of the first one-way valve 4, the hydraulic oil will not flow back to the reversing oil circuit 12, thereby improving the safety of the hydraulic system operation.

[0036] At the same time, it also includes a first hydraulic lock 21, which is connected to the first rodless chamber oil circuit 22 and the first rod chamber oil circuit 23. The first hydraulic lock 21 provides hydraulic oil pressure protection for the first clamping oil cylinder 2 in the clamping or loosening state. The oil inlet of the first rod chamber oil circuit 23 is A1, and the oil inlet of the first rodless chamber oil circuit 22 is B1. After the hydraulic oil enters the rod chamber of the first clamping oil cylinder 2 from the A1 port through the first rod chamber oil circuit 23 and then through the first hydraulic lock 21, or enters the rodless chamber of the first clamping oil cylinder 2 from the B1 port through the first rodless chamber oil circuit 22 and then through the first hydraulic lock 21, the oil supply is stopped, and the first hydraulic lock 21 immediately enters the pressure holding state to prevent the hydraulic oil in the first clamping oil cylinder 2 from flowing out, ensuring the clamping or loosening state of the front top clamp. It should be noted that the oil outlet of the first check valve 4 is connected to the oil outlet of the rodless chamber of the first clamping oil cylinder 2 connected to the first hydraulic lock 21.

[0037] Similarly, the two rodless chambers in the second clamping oil cylinder 3 are connected to the same second rodless chamber oil circuit 32, and the two rod chambers in the second clamping oil cylinder 3 are connected to the same second rod chamber oil circuit 33. The second rod chamber oil circuit 33 and the second rodless chamber oil circuit 32 respectively allow hydraulic oil to enter through the A2 port and the B2 port, thereby controlling the clamping or loosening of the rear top clamp by controlling the pressure of the rodless chamber and the rod chamber inside the second clamping oil cylinder 3. Similarly, the second rodless chamber oil circuit 32 and the second rod chamber oil circuit 33 are connected to the second hydraulic lock 31, which has the same function as the first hydraulic lock 21 and will not be described here. An oil branch is also provided between the reversing oil circuit 12 and the second rodless chamber oil circuit 32 for communication. A second one-way valve 5 is provided on the oil branch for control. The second one-way valve 5 also only allows the hydraulic oil in the reversing oil circuit 12 to flow to the second rodless chamber oil circuit 32 in one direction, so as to replenish the hydraulic oil of the second clamping oil cylinder 3 during the unhooking operation and the reversal of the power head motor 1, thereby increasing the clamping force of the rear top clamp and further preventing the phenomenon of slipping during unhooking. The first clamping oil cylinder 2 and the second clamping oil cylinder 3 are both provided with separate oil supply circuits to meet the working requirements of a single top clamp during drilling and adapt to more different drilling operation requirements.

[0038] In this embodiment, the oil inlets of the first one-way valve 4 and the second one-way valve 5 are interconnected and connected to the reversal oil circuit 12 at the same time, so as to further simplify the hydraulic system oil circuit and ensure that when the reversal oil circuit 12 is passed, the front top clamp and the rear top clamp that perform clamping work synchronously can be replenished with hydraulic oil at the same time to ensure the clamping strength of the two top clamps.

[0039] Since there is a situation where a single top clamp is clamped in actual operation, for the convenience of understanding, this embodiment is set as the front top clamp is clamped and the rear top clamp is released. At this time, under the reverse cut-off action of the first one-way valve 4, the rodless chamber of the first clamping oil cylinder 2 and the rodless chamber of the second clamping oil cylinder 3 are not connected to each other. Therefore, although the oil circuits of the oil inlet of the first one-way valve 4 and the second one-way valve 5 are connected, it will not affect the oil circuit control of the second clamping oil cylinder 3 to the released state of the rear top clamp. And under the action of the second one-way valve 5, it will not affect the normal operation of the reverse oil circuit 12 of the power head motor 1, further ensuring the safety of the operation of the hydraulic system.

[0040] In addition, when the power head motor 1 rotates forward, the hydraulic oil in the forward oil circuit 11 enters through port A, and then flows out from port B through the reverse oil circuit 12 to complete the oil return. When the return oil flows inside the reverse oil circuit 12, it is inevitable that a part of the hydraulic oil will flow to the first one-way valve 4 and the second one-way valve 5 respectively, causing a certain impact on the top clamp that originally needs to be kept in a loose state. Therefore, in this embodiment, the opening pressure of the first one-way valve 4 and the second one-way valve 5 is further set to be higher than the return oil pressure in the reverse oil circuit 12, thereby ensuring that the oil inlet valve of the one-way valve will not open, avoiding the impact of the operating safety and stability of the original equipment due to the setting of the branch oil circuit. In addition, the current top clamp and the rear top clamp are in a loosened state, and the rod chambers in the first clamping cylinder 2 and the second clamping cylinder 3 are in a high-pressure state under the pressure-maintaining action of the first hydraulic lock 21 and the second hydraulic lock 31, and the rodless chambers are in a return oil low-pressure chamber state. Therefore, even in the extreme case where the first one-way valve 4 and the second one-way valve 5 fail, based on the pressure difference between the rod chamber and the rodless chamber, the loosened state of the two top clamps can be ensured to be unaffected, that is, a double insurance effect of loosening and maintaining the top clamps is formed, ensuring that the top clamps in the hydraulic system will not affect the normal drilling work and can ensure the safety of construction.

[0041] The specific implementation process is as follows:

[0042] When the drill rod is connected, the power head motor 1 drives the power head to rotate forward. According to the working principle of the drilling rig, the front top clamp and the rear top clamp must be kept in a loose state at the same time, that is, before the power head rotates forward, hydraulic oil must be introduced into the rod chambers in the first clamping oil cylinder 2 and the second clamping oil cylinder 3 through the A1 port and the A2 port respectively, and all piston rods are controlled to retract so that the front top clamp and the rear top clamp are in a loose state that does not affect the rotation of the drill rod, and then oil is introduced into the forward oil circuit 11 through the A port to start the power head motor 1 to rotate forward. At the same time, because the opening pressure of the oil inlet valve of the first check valve 4 and the second check valve 5 is set to be higher than the return oil pressure in the reverse oil circuit 12, and under the dual effect of the pressure difference between the rod chamber and the rodless chamber of each oil cylinder, even if part of the return hydraulic oil in the reverse oil circuit 12 enters the first check valve 4 and the second check valve 5, the loose state of the two top clamps can still be ensured.

[0043] When the drill rig is unloading the drill, the power head motor 1 drives the power head to drive the active drill rod to reverse, and clamps the front drill rod through the top clamp. The power head reverses to loosen the threaded connection between the active drill rod installed on the power head and the front drill rod.

[0044] Here, it is set to the working state that the front top clamp and the rear top clamp synchronously clamp the front drill rod. Before unbuckling, oil is passed to the rodless chambers in the first clamping oil cylinder 2 and the second clamping oil cylinder 3 through the first rodless chamber oil circuit 22 and the second rodless chamber oil circuit 32, respectively, so that the front top clamp and the rear top clamp synchronously clamp the front drill rod; after the oil supply is completed, the first clamping oil cylinder 2 and the second clamping oil cylinder 3 are respectively maintained by the first hydraulic lock 21 and the second hydraulic lock 31 to ensure the clamping force; and then oil is passed to the power head motor 1 through the reversing oil circuit 12 to drive the power head to start reversing. When the power head motor 1 reverses, the hydraulic oil in the reversing oil circuit 12 enters the rodless chamber of the first clamping oil cylinder 2 and the rodless chamber of the second clamping oil cylinder 3 through the first one-way valve 4 and the second one-way valve 5, respectively, and the linkage pressurization of the two clamping oil cylinders is formed synchronously, so as to achieve the purpose of preventing the top clamp from slipping by ensuring the clamping force of the clamping oil cylinder.

[0045] When breaking the bolt, the tightness of the threaded joints between the drill pipes is different. When the breaking load (i.e., the reversing load of the power head) increases, the clamping force required by the top clamp needs to be increased accordingly. In this embodiment, when the reversing pressure of the power head motor 1 increases, the hydraulic oil of the reversing oil circuit 12 enters to compensate for the leakage of the respective hydraulic locks and clamping cylinders, thereby preventing the top clamp from slipping when breaking the bolt.

[0046] It should be noted that when a single top clamp is working, that is, one top clamp is in a clamping working state and is pressurized by the hydraulic system, the other top clamp is in a loose state. At this time, since the hydraulic lock connected to the top clamp in the loose state has a reverse locking effect, the reverse pressurized hydraulic oil will not cause the top clamp in the loose state to clamp. Moreover, since the stroke of the clamping cylinder in the actual drilling rig is relatively long, even if a small amount of leakage occurs in the clamping cylinder or the hydraulic lock, it will not affect the loose state of the top clamp.

[0047] This solution connects the reverse oil circuit 12 of the power head motor 1 and the rodless chamber oil circuit in the top clamp, and sets a one-way valve to cooperate with the hydraulic lock, ultimately forming an anti-skid hydraulic system for the top clamp in which reverse linkage boosting and forward rotation and single motion of the clamp do not affect each other. This solves the problem of slipping caused by the reduction of the clamping force of the top clamp due to leakage of the clamping cylinder and the hydraulic lock in the existing hydraulic system of the top clamp, thereby ensuring on-site construction safety and improving construction efficiency.

[0048] Example 2

[0049] like Figure 2-10As shown, a top clamp connected to the hydraulic system described in Example 1 is provided. The top clamp is a double top clamp. By improving the existing double top clamp structure, its anti-slip function is further improved, and the difficulty of operating the top clamp during use is reduced, thereby improving work efficiency.

[0050] Due to the structural limitations of the drilling rig, when replacing large drilling tools with larger apertures (for example, replacing them with bottom hole motors) at existing construction sites, two methods are generally used: one is to tilt the bottom hole motor at a certain angle relative to each axis of the through hole of the top clamp (i.e., the drilling axis) and then insert it into the top clamp, but this method has a very limited scope of application. When the distance between the top clamp and the hole wall is too small, the overly tilted bottom hole motor will not be able to align with the inner hole of the top clamp. The other method is to dismantle the top clamp as a whole, install the bottom hole motor and send it into the hole, and finally install the top clamp back. This method has a wide range of applications and can be used even when the distance between the top clamp and the hole wall is very small, but the top clamp is large in size, heavy in weight, and complex in structure. The overall disassembly will consume a lot of manpower and construction time, seriously reducing construction efficiency. There are also huge safety hazards in the operation, and the operation is difficult.

[0051] Based on this, Figure 2 As shown, the double top clamp includes a base 6 and a front top clamp mounting portion and a rear top clamp mounting portion disposed on the base 6, and the front top clamp mounting portion and the rear top clamp mounting portion are used to connect the front top clamp and the rear top clamp respectively. Figure 3 As shown, the bottom surface of the base 6 is a mounting plate 61, and the front-to-top clamp mounting portion includes a front support plate 63 and a rear support plate 65 symmetrically arranged on the mounting plate 61. A through hole is provided on the front support plate 63 and the rear support plate 65, and the two through holes are coaxial after being provided. An opening is provided at the upper end of the through hole, and the width of the opening is greater than or equal to the diameter of the bottom hole motor. The additional opening makes the through holes of the front support plate 63 and the rear support plate 65 for accommodating the drill rod open upward, so that the drilling rig can operate from top to bottom when replacing large-diameter drill rods such as the bottom hole motor, that is, the original method of extracting and disassembling the drill rod along the front and rear ends of the through hole axis is changed to directly taking it out or putting it in from the top of the through hole, which greatly reduces the space required for disassembly and also reduces the difficulty of replacing the drill rod.

[0052] At the same time, if Figure 3As shown, a reinforcing plate 64 is detachably connected to the openings of the two through holes. The connection method of the reinforcing plate 64 is taken as an example of the front support plate 63: a convex block and a concave block are set on the top of the front support plate 63, and a concave block and a convex block matching the convex block and concave block on the top of the front support plate 63 are set on the bottom of the reinforcing plate 64. The upper and lower convex blocks and concave blocks are interlaced and nested to form a complete plane, which improves the overall structural strength of the support plate 71 and facilitates the positioning assistance when installing the reinforcing plate 64; finally, the reinforcing plate 64 is fixed to the front support plate 63 by screws or pins. The reinforcing plate 64 ensures the integrity of the through hole during the drilling operation and avoids safety accidents caused by the collapse of the through hole.

[0053] Combination Figure 2 and Figure 4 As shown, a swing body 7 is arranged between the front support plate 63 and the rear support plate 65. The swing body 7 includes two support plates 71 symmetrically arranged front and back. Both support plates 71 are provided with guide mounting holes, and connecting flanges are arranged in the guide mounting holes. Figure 4 Direction, a flip shaft seat 75 is provided at the lower right side of the support plate 71, and the outer end faces on both sides of the two support plates 71 are respectively connected to a front cylinder mounting plate 72, and the first clamping cylinder 2 is installed on the front cylinder mounting plate 72 by bolts, and a swing ear seat 74 is fixedly connected to the lower side of the front cylinder mounting plate 72 near the flip shaft seat 75, and a swing cylinder 77 is rotatably connected to the swing ear seat 74 by setting a rotating shaft. Four front lining plates 73 are symmetrically provided between the two support plates 71, and the four front lining plates 73 are spliced ​​to form a guiding space for the movement of the clamping cylinder piston rod, and can also support the swinging part structure. At the same time, Figure 3 As shown, the front support plate 63 and the rear support plate 65 are fixedly connected to the flip plate 62 on one side close to the flip shaft seat 75, and the flip plate 62 is provided with a flip hole, and the flip hole is installed with a flip pin 76 as the flip axis of the swing body 7. The swing body 7 is the main connecting part of the various parts in the front top clamp, which connects the first clamping cylinder 2 and the base 6 into one, and connects the front top clamp and the frame of the drilling rig into one through the swing cylinder 77.

[0054] like Figure 1 and Figure 8As shown, the swing cylinder 77 is a driving element that drives the swing body 7 to rotate around the flip pin 76. The piston rod of the swing cylinder 77 is hinged to the swing ear seat 74 of the swing body 7 through the pin, and the cylinder barrel of the swing cylinder 77 is hinged to the frame of the drilling rig through the pin. The flip pin 76 is the axis of the swing body 7 flip. The end of the flip pin 76 close to the swing body 7 is inserted into the flip shaft seat 75 of the swing body 7, and the other end is inserted into the through hole of the flip plate 62 of the base 6, and is limited at the end by a split pin or a retaining ring. The swing body 7 mechanically swings out of the base 6 by switching the rotation center, combined with the detachable reinforcement plate 64 structure of the base 6, thereby giving up a lot of space inside and above the front top clamp, and realizing the installation of the bottom hole motor from top to bottom. This process only requires the disassembly and assembly of a small number of parts, which not only reduces the space requirement for the front end of the clamp for the installation of the bottom hole motor, but also saves a lot of time and manpower for the overall removal of the clamp.

[0055] The clamping device clamps the drill pipe by connecting the slips to the piston rods of the two symmetrically arranged clamping cylinders. Figure 5 and Figure 6 As shown, the slips include an outer slip 8 and an inner slip 81. The inner surface of the outer slip 8 is provided with a number of protrusions or fine sharp teeth for increasing the friction force with the clamping contact surface of the drill pipe. The diameter of the inner surface arc section of the outer slip 8 matches the outer diameter of the inner slip 81. The inner surface of the outer slip 8 is provided with three countersunk holes, which are used to install screws for connecting the piston rod in the clamping oil cylinder. The upper and lower parts of the arc section are provided with a plane, which is provided with threaded holes, which are used to install the screws for connecting the inner slip 81; a clamp block is provided at each of the four corners of the plane, and the four stop planes of the four clamp blocks are combined with the arc surface to form an installation space for connecting the inner slip 81. Symmetrical bosses are provided on both the upper and lower sides of the inner slip 81. The bosses facing the center of the clamp are provided with countersunk through holes, which are used to install screws connected to the outer slip 8. The outer diameter of the inner slip 81 matches the inner diameter of the outer slip 8, which is convenient for installation. Several bumps or small sharp teeth are also provided on the inner surface of the inner slip 81 to make the clamping more stable. The front projection of the inner slip 81 is a "cross" shape, which cooperates with the four stop planes on the outer slip 8 to achieve positioning along the front and rear axis of the clamp.

[0056] The inner diameter of the inner slip 81 matches the outer diameter of the drill pipe with a smaller diameter, and the inner diameter of the outer slip 8 matches the outer diameter of the drill pipe with a larger diameter. When replacing drill pipes of different sizes, the clamping adjustment can be performed by removing or adding the inner slip 81. The replacement operation can be performed by removing or installing the inner slip 81 by screwing the screws, which further improves the convenience of operation of the double top clamp. The cylinder barrel of the first clamping cylinder 2 is symmetrically fixed on the front cylinder mounting plates 72 on both sides of the swing body 7. The piston rod of the first clamping cylinder 2 extends from both sides of the front top clamp to the center, and clamps and drives the drill pipe through the slips on the piston rod.

[0057] When replacing the inner cava 81, the clamping cylinder retracts to form an open space for disassembling and installing the cava. The cava can be quickly replaced by removing and installing a few screws, which is convenient and quick to operate. In addition, the inner cava 81 uses a larger plane to achieve axial positioning of the clamp, and uses screws to achieve radial positioning along the arc. The plane bears the shear force instead of the screw, which greatly reduces the possibility of deformation of the screw under stress and improves the reliability of positioning to prevent slipping when removing the buckle. In addition, by quickly disassembling and assembling the inner cava 81 and the outer guide sleeve 9 to achieve switching of the applicable drill pipe outer diameter, the applicable scope of the clamp is also improved, especially for situations where a directional drill rig uses ordinary drill pipes, salvage drill pipes, bottom hole motors and other special drilling tools at the same time.

[0058] Combination Figure 2 and Figure 7 As shown, the front top clamp also includes a guide sleeve group, which includes an outer guide sleeve 9 and an inner guide sleeve 91, and the inner guide sleeve 91 and the outer guide sleeve 9 are detachably connected in the through hole, so that the guide sleeve is integrated into the clamp to save installation space and make the overall layout of the drilling rig more compact.

[0059] like Fig. 9 As shown, the outer diameter of the inner guide sleeve 91 is divided into two levels. The small diameter section of the inner guide sleeve 91 cooperates with the guide installation hole on the swing body 7, and the large diameter section of the inner guide sleeve 91 cooperates with the through holes in the middle of the front support plate 63 and the rear support plate 65 of the base 6 to achieve axial limit. At the same time, the inner diameter of the inner guide sleeve 91 is also divided into two levels, wherein the small diameter section of the inner diameter is an equal diameter through hole, which cooperates with the small diameter section of the outer diameter of the outer guide sleeve 9; the large diameter section of the inner diameter is a countersunk stage, which cooperates with the outer guide sleeve 9. Figure 8 As shown, the outer diameter of the outer guide sleeve 9 is also divided into two levels, wherein a countersunk connection hole is provided on the end surface of the large diameter section of the outer guide sleeve 9, and the countersunk connection hole is used to install screws to fix the outer guide sleeve 9 and the inner guide sleeve 91 on the swing body 7; the bottom surface of the large diameter section of the inner guide sleeve 91 is provided with a through hole corresponding to the outer guide sleeve 9, and the outer guide sleeve 9 and the inner guide sleeve 91 are fixed on the swing body 7 by setting screws in the through hole. Figure 7As shown, the large diameter section of the outer guide sleeve 9 cooperates with the stage section of the inner guide sleeve 91 to achieve axial limit of the outer guide sleeve 9; the inner diameter of the outer guide sleeve 9 matches the outer diameter of the smaller drill rod applicable to the drilling rig to guide the drill rod to the top clamp before entering and exiting. The two parts of the inner guide sleeve 91 and the outer guide sleeve 9 have obvious differences in structure, which is convenient for on-site accessory management and identification.

[0060] Finally, combine Figure 1 and Figure 2 As shown, the rear top clamp mounting portion includes a symmetrically arranged front side plate 69 and a rear side plate 67. The front side plate 69 and the rear side plate 67 serve as support members for the rear top clamp. The middle portions of the front side plate 69 and the rear side plate 67 are provided with U-shaped holes. The U-shaped holes allow the tops of the front side plate 69 and the rear side plate 67 to be completely open. Four rear lining plates 66 are symmetrically arranged between the front side plate 69 and the rear side plate 67. The four rear lining plates 66 form a guide space for the movement of the second clamping cylinder 3 and the cylinder piston rod, and also play a structural support role. Rear cylinder mounting plates 68 are connected to the outer end surfaces on both sides of the front side plate 69 and the rear side plate 67. The second clamping cylinder 3 is fixedly connected to the rear cylinder mounting plates 68 by bolts. Semi-ring guide sleeves 92 are connected to the U-shaped holes. Fig.10 As shown, the outer diameter of the semi-ring guide sleeve 92 is also divided into two levels, the small diameter section of the semi-ring guide sleeve 92 matches the U-shaped hole, and the large diameter section of the semi-ring guide sleeve 92 is provided with a countersunk connecting hole on the end surface, and the countersunk connecting hole is used to install screws to fix the semi-ring guide sleeve 92 on the front side plate 69 or the rear side plate 67. The inner diameter of the semi-ring guide sleeve 92 matched with the U-shaped hole can match the drill rods of different outer diameters of the drilling rig, and the drill rods are loaded into the clamp from the top opening.

[0061] In the traditional drilling rig structure, the clamp and the guide sleeve are generally arranged at the front end of the frame as two independent components, occupying a large length space. In order to save space in the drilling direction, some drilling rigs even cancel the guide sleeve. The inner sleeve of the traditional guide sleeve is a rotatable hollow cylinder. One inner sleeve can only adapt to a drill rod with an outer diameter. After the drill rod is replaced, the guide sleeve must be replaced as a whole or the inner sleeve must be replaced separately to adapt to the outer diameter of the new drill rod. It is relatively simple to replace the guide sleeve as a whole, but the spare parts cost is high; it is relatively complicated to replace the inner sleeve separately, but the cost is low, which is the method currently commonly used on site. There is also a problem of difficult identification and management of accessories when replacing the inner sleeve separately. Since the specifications of several drill rods used in the same drilling rig are similar, the diameter difference of the drill rod is generally about 10mm, which is reflected in the thickness difference of the inner sleeve of only a few millimeters. It is very difficult to identify such a small gap without a measuring tool on the underground site, so the on-site accessory management is also relatively difficult. The above-mentioned method of assembling the guide sleeve on the clamp in this embodiment just solves this problem, and further improves the convenience of operation of the double top clamp.

[0062] In this embodiment, on the basis of the hydraulic system's slipping function in Embodiment 1, the inner diameter of the outer slip 8 is matched with the outer diameter of the larger drill pipe, and the inner diameter of the inner slip 81 is matched with the outer diameter of the smaller drill pipe, so that during the construction process, adaptive slip matching can be performed according to different drill pipe diameters, thereby further improving the clamping strength of the double top clamp on the drill pipe and avoiding slipping during the clamping process. In addition, the inner slip 81 uses a larger plane to achieve axial positioning of the top clamp, and screws are used to achieve radial positioning along the arc. The plane bears part of the shear force for the screw, greatly reducing the possibility of deformation of the screw under stress, further improving the reliability of the positioning of the inner slip 81, and improving the clamping strength of the smaller diameter drill pipe shackle, thereby ensuring on-site construction safety and improving construction efficiency.

[0063] The front projection of the inner slip 81 is set to be a "cross" shape, and it is symmetrically provided with four positioning planes, which cooperate with the four stop planes corresponding to the outer slip 8 to achieve the positioning of the inner slip 81 along the front and rear axial direction of the clamp. The positioning of the inner slip 81 in the arc radial direction (i.e., the telescopic direction of the clamping cylinder) is achieved by the screws connected to the outer slip 8. This positioning method makes good use of the advantages of the high tensile strength of the threaded connection, while avoiding the characteristics of the weak shear strength of the bolt, and greatly reduces the possibility of deformation of the slip positioning parts. When the inner slip 81 is severely worn or needs to be replaced from a smaller outer diameter drill rod to a larger outer diameter drill rod, the inner slip 81 needs to be disassembled. At this time, it is only necessary to retract the piston rod of the clamping cylinder and unscrew the connecting screws between the inner slip 81 and the outer slip 8.

[0064] The above is only an embodiment of the present invention, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. The anti-skid hydraulic system of the top clamp, the power head motor is connected with a forward oil circuit and a reverse oil circuit, which are characterized by: The rodless chamber of the first clamping oil cylinder is connected to the first rodless chamber oil circuit, the rod chamber of the first clamping oil cylinder is connected to the first rod chamber oil circuit, a first check valve is provided between the reversing oil circuit and the first rodless chamber oil circuit for connection, the first check valve is used for allowing the oil in the reversing oil circuit to flow to the first rodless chamber oil circuit in one direction; It also includes a second clamping oil cylinder, the rodless chamber of the second clamping oil cylinder is connected to a second rodless chamber oil circuit, the rod chamber of the second clamping oil cylinder is connected to a second rod chamber oil circuit, a second one-way valve is provided between the reversing oil circuit and the second rodless chamber oil circuit for connection, and the second one-way valve is used to allow the oil in the reversing oil circuit to flow to the second rodless chamber oil circuit in one direction; The oil inlet valve opening pressures of the first one-way valve and the second one-way valve are set to be higher than the oil return pressure in the reversing oil circuit; The top-to-top clamp is a double top-to-top clamp, which includes a base and a front top-to-top clamp mounting part and a rear top-to-top clamp mounting part arranged on the base, the front top-to-top clamp mounting part and the rear top-to-top clamp mounting part are respectively used to connect the front top-to-top clamp and the rear top-to-top clamp, the bottom surface of the base is a mounting plate, the front top-to-top clamp mounting part includes a front support plate and a rear support plate symmetrically spaced on the mounting plate, a through hole is provided on the front support plate and the rear support plate, the two through holes are coaxial after the opening, an opening is provided on the upper end of the through hole, and the width of the opening is greater than or equal to the diameter of the bottom hole motor; The drill pipe is clamped by the clamp by connecting the slips to the piston rods of the symmetrically arranged first clamping cylinder and the second clamping cylinder respectively. The slips include external slips and internal slips. The internal slips use a larger plane to achieve axial positioning of the top clamp, and screws are used to achieve radial positioning along the arc.

2. The anti-skid hydraulic system for the top clamp according to claim 1, characterized in that: The oil inlet end of the second one-way valve is communicated with the oil inlet end of the first one-way valve.

3. The anti-skid hydraulic system for the top clamp according to claim 2, characterized in that: It also includes a first hydraulic lock, which is connected to the first rodless chamber oil circuit and the first rod chamber oil circuit.

4. The anti-skid hydraulic system for the top clamp according to claim 3, characterized in that: It also includes a second hydraulic lock, which is connected to the second rodless chamber oil circuit and the second rod chamber oil circuit.

5. The anti-skid hydraulic system for the top clamp according to claim 4, characterized in that: The oil outlet of the first one-way valve is connected to the oil outlet of the first hydraulic lock to the rodless chamber of the first clamping oil cylinder.

6. The anti-skid hydraulic system for the top clamp according to claim 5, characterized in that: The oil outlet of the second one-way valve is connected to the oil outlet of the second hydraulic lock to the rodless chamber of the second clamping oil cylinder.

7. The anti-skid hydraulic system for the top clamp according to claim 6, characterized in that: The first rod chamber oil circuit and the first rodless chamber oil circuit are respectively connected to port A1 and port B1 to allow hydraulic oil to enter; the second rod chamber oil circuit and the second rodless chamber oil circuit are respectively connected to port A2 and port B2 to allow hydraulic oil to enter.

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