A rotary excavator with multiple anti-jamming control

Abstract

This invention discloses a rotary drilling rig with multiple anti-jamming controls, relating to the field of rotary drilling rigs. In mountainous areas with complex geological conditions, rotary drilling rigs are highly susceptible to jamming during excavation. The rotary drilling rig of this invention is equipped with a feed anti-jamming hydraulic system, a slewing anti-jamming hydraulic system, and a cutting head anti-jamming structure. The feed anti-jamming hydraulic system monitors the difference between the cutting head's slewing pressure and the hydraulic control pressure, automatically reversing the feed cylinder to remove the jam when jamming occurs during the cutting head's feed. The slewing anti-jamming hydraulic system monitors the difference between the cutting head's slewing pressure and the pressure set by the overflow valve, automatically reversing the slewing mechanism to remove the jam when jamming occurs during the cutting head's revolution and rotation. The cutting head anti-jamming structure includes anti-fragment components and nozzle channels arranged circumferentially around the cutting head. This effectively reduces the risk of jamming in complex geological conditions in mountainous areas, improving operational reliability and safety.

Description

Technical Field

[0001] This invention relates to the field of rotary drilling rigs, and more particularly to a rotary drilling rig with multiple anti-jamming controls. Background Technology

[0002] In the field of foundation excavation for power transmission lines, especially in the construction of foundations in complex mountainous terrain, traditional manual excavation methods are inefficient and labor-intensive, making it difficult to meet the safety and construction progress requirements of modern engineering projects. With the development of mechanization technology, modular hydraulic rotary drilling rigs, with their advantages such as light weight and the ability to be transported to mountainous work sites by cableway, have become key equipment for foundation excavation in mountainous areas and are widely used in power transmission and transformation projects and other fields.

[0003] However, mountainous areas have complex geological conditions and diverse rock structures, including cracks, caves, and transitional zones with uneven hardness, making rotary drilling rigs highly susceptible to jamming during excavation. Jamming occurs when the rotational resistance torque of the cutting head exceeds the maximum torsional torque provided by the hydraulic system, causing the drill bit to become stuck and unable to operate normally. Jamming not only interrupts construction and requires significant time to remove the stuck drill bit, but in severe cases, it can also cause drill bit breakage, hydraulic system damage, and other equipment malfunctions, significantly reducing construction efficiency and increasing direct costs and project timeline risks.

[0004] Existing anti-jamming measures for rotary drilling rigs are mostly designed for single working conditions or single action stages, and their mechanisms are relatively simple. They are ill-suited to address the diverse jamming scenarios in complex geological conditions, such as sudden jamming in karst caves, gradual jamming in rock fissures, and rapid jamming in cracked areas. Therefore, developing a multi-layered anti-jamming control technology that covers the main operating stages of rotary drilling rigs, including feeding and revolution / rotation, and incorporates optimized physical structures, to proactively prevent and promptly address different types of jamming, is a key requirement for improving the reliability and efficiency of modular hydraulic rotary drilling rigs operating in complex geological conditions in mountainous areas. Summary of the Invention

[0005] The technical problem to be solved and the technical task proposed by this invention is to improve and refine existing technical solutions, and to provide a rotary drilling rig with multiple anti-jamming controls, so as to reduce the risk of jamming in complex geological conditions in mountainous areas and improve operational reliability and safety. To this end, this invention adopts the following technical solution.

[0006] A rotary drilling rig with multiple anti-jamming controls, the rotary drilling rig includes an upper platform, a lower platform, a slewing bearing, a slewing platform, a reducer, a cutting head, a feed cylinder, a guide column, support legs, and a revolution and rotation motor. The rotary drilling rig is equipped with a multiple anti-jamming system, which includes a feed anti-jamming hydraulic system, a slewing anti-jamming hydraulic system, and a cutting head anti-jamming structure.

[0007] The aforementioned anti-jamming hydraulic system is associated with the feed cylinder. By monitoring the difference between the rotation pressure of the cutting head rotary motor and the hydraulic control pressure, it automatically reverses the direction of the feed cylinder to remove the jam when the drill gets stuck during the cutting head feeding process.

[0008] The aforementioned anti-jamming hydraulic system is associated with the revolution and revolution rotation motor. By monitoring the difference between the rotation pressure of the cutting head rotation motor and the pressure set by the overflow valve, it automatically reverses the direction and controls the rotation mechanism to retract and remove the jam when the drill gets stuck during the revolution and revolution of the cutting head.

[0009] The aforementioned anti-jamming structure of the cutting head is used to physically isolate rock powder and clear stuck debris, including anti-fragmentation components and nozzle channels arranged circumferentially along the cutting head.

[0010] By setting up multiple anti-jamming systems, integrating the feed anti-jamming hydraulic system, the slewing anti-jamming hydraulic system, and the cutting head anti-jamming structure, a three-dimensional anti-jamming system covering the entire process of rotary drilling rig feeding, slewing, and cutting operations is constructed. The feed and slewing anti-jamming systems automatically respond to drill jamming based on pressure difference monitoring, while the cutting head anti-jamming structure reduces rock powder jamming from a physical perspective. The three systems work together to effectively reduce the risk of drill jamming in complex geological conditions in mountainous areas, eliminating the need for frequent manual intervention. This aligns with the trend of modular equipment development, making it easy to promote in mountainous areas and improving operational safety, reliability, and efficiency.

[0011] As a preferred technical means: the feed anti-jamming hydraulic system includes a first hydraulically controlled two-position four-way directional valve and a pressure reducing valve;

[0012] The first control port of the first hydraulically controlled two-position four-way directional valve is connected to the rotary pressure oil source of the cutting head, and the second control port is connected to the system pressure oil source through the pressure reducing valve. The pressure reducing valve outputs hydraulically controlled pressure Pk.

[0013] The working port of the first hydraulically controlled two-position four-way directional valve is connected to the feed cylinder.

[0014] When the rotary pressure P1 generated by the cutting head rotary motor is less than or equal to Pk, the first hydraulically controlled 2-position 4-way directional valve is in the left position, and the feed cylinder feeds normally. When P1 > Pk, the first hydraulically controlled 2-position 4-way directional valve reverses, and the feed cylinder retracts to release the stuck drill bit. The feed anti-jamming hydraulic system uses the first hydraulically controlled 2-position 4-way directional valve and the pressure reducing valve to compare the rotary pressure P1 and the hydraulic control pressure Pk generated by the cutting head rotary motor in real time. When P1 exceeds the threshold, it can immediately trigger the feed cylinder to retract, preventing the drill bit from getting stuck and reducing drill bit wear.

[0015] As a preferred technical means: the rotary anti-jamming hydraulic system includes a second hydraulically controlled two-position four-way directional valve, an overflow valve, and a speed regulating valve;

[0016] The first control port of the second hydraulically controlled two-position four-way directional valve is connected to the rotary pressure oil source of the cutting head. The second control port of the second hydraulically controlled two-position four-way directional valve is connected to the overflow valve in sequence through the speed regulating valve. The other end of the overflow valve is connected back to the oil tank.

[0017] The working port of the second hydraulically controlled two-position four-way directional valve is connected to the rotary mechanism driven by the revolution-rotation motor;

[0018] When the rotary motor of the cutting head generates a rotary pressure P1 that is less than or equal to the set pressure of the relief valve, the second hydraulically controlled two-position four-way directional valve is in its normal operating position, and the revolution rotary mechanism operates normally. When P1 exceeds the set pressure of the relief valve, the second hydraulically controlled two-position four-way directional valve reverses, and the rotary mechanism retracts to release the stuck drill. The rotary anti-jamming hydraulic system uses the relief valve and the speed control valve to form a pressure monitoring circuit, which monitors the rotary pressure separately. If the drill gets stuck in a crack, it can immediately trigger a reverse retraction to avoid forced overload of the equipment.

[0019] As a preferred technical means, the cutting head anti-jamming structure includes an anti-rock fragment component, which is an annular baffle or flange arranged circumferentially along the cutting head to prevent rock fragments from entering the connection gap between the cutting head and the drill pipe. The annular baffle or flange constructs a physical barrier to prevent rock powder from entering the critical gap, reducing the risk of mechanical jamming and extending the equipment maintenance cycle.

[0020] As a preferred technical approach: the nozzle channels are arranged spirally on the outer circumference of the cutting head, with each nozzle's nozzle located at the bottom of the channel. This arrangement uses water or air to clear stuck rock powder and fragments. The nozzle channels are arranged in the same direction as the spiral blades, utilizing water or air to efficiently remove stuck rock powder. The system allows for switching between water and air media; water washing is used for cooling and preventing stuck rocks from clogging, while air washing is suitable for water-scarce mountainous areas, improving the equipment's environmental adaptability.

[0021] As a preferred technical approach, the hydraulic system of the rotary drilling rig is a three-pump tandem pump system. The working pressure and flow rate of the cutting head rotation, feed cylinder feed, and revolution / slewing motor can be independently adjusted. Specifically, the pressure adjustment of the pressure reducing valve in the feed anti-jamming hydraulic system and the pressure adjustment of the relief valve in the revolution anti-jamming hydraulic system are both achieved through independent pressure branches of the three-pump tandem pump system, adapting to the anti-jamming pressure requirements under different rock hardness conditions. It allows for precise adjustment of various action parameters such as feed pressure and revolution speed, improving flexibility in handling complex mountainous geological conditions. An anomaly in one anti-jamming circuit does not affect other circuits, ensuring the overall stability of the equipment and providing reliable power support for the implementation of anti-jamming strategies.

[0022] As a preferred technical means, in the aforementioned feed anti-jamming hydraulic system, the output pressure Pk of the pressure reducing valve can be adjusted according to the rock hardness, with an adjustment range of 60%-80% of the system working pressure. It is adaptable to different geological conditions such as soft and hard rock. For soft rock, Pk is lowered to improve anti-jamming sensitivity, while for hard rock, Pk is raised to avoid false triggering. This allows the equipment to intelligently adapt to the varied geological conditions in mountainous areas. If linked with a rock hardness sensor, it can also dynamically adjust parameters in real time based on geological changes. The hydraulic reversing logic is simple and reliable, resistant to interference from harsh environments such as dust and vibration in mountainous areas, improving the equipment's versatility and stability under varying geological conditions, achieving fully automated intelligent operation, reducing manual intervention, and improving operational efficiency and accuracy.

[0023] As a preferred technical means, in the aforementioned rotary anti-jamming hydraulic system, the set pressure of the relief valve can be adjusted according to the rock hardness, with an adjustment range of 70%-90% of the rated working pressure of the rotary motor. The speed control valve is used to stabilize the control pressure of the relief valve. This ensures normal rotary power while triggering protection in time when the drill is stuck. The speed control valve stabilizes the control pressure of the relief valve, suppresses pressure fluctuations, and ensures that the system responds stably under high-pressure impact, protecting the rotary motor and improving the reliability of the equipment in complex geological operations in mountainous areas.

[0024] As a preferred technical means, the aforementioned multi-layer anti-jamming system can cope with three types of drill jamming conditions:

[0025] Type A stuck drill bit in karst cave: When the cutting head suddenly encounters collapse resistance after entering the rock cavity, the rotation pressure P1 rises instantaneously and P1>1.2Pk, or 1.2 times the overflow valve setting pressure. When the feed / rotation anti-jamming is triggered, the feed anti-jamming hydraulic system and the rotation anti-jamming hydraulic system are triggered to retract the cutter simultaneously. The feed cylinder retracts and the rotation mechanism retracts to remove the jam.

[0026] Type B Gradual Jamming: When the cutting head encounters progressively increasing resistance in the crack layer or gravel area, and the slewing pressure P1 continues to rise to P1 > 0.8Pk, or 0.8 times the set pressure of the relief valve and the increase rate is ≥ 0.5MPa / s, the anti-jamming hydraulic system gradually reduces the feed speed of the feed cylinder by slightly reversing the directional valve or by finely adjusting the flow rate of the slewing mechanism by the speed regulating valve until the resistance returns to normal.

[0027] Type C Crack Jamming: When the cutting head suddenly jams due to a rock crack, and the rotary pressure P1 surges and P1 > 1.5Pk, or reaches 1.5 times the pressure set by the relief valve, the anti-jamming hydraulic system immediately triggers a reverse retraction action. The feed cylinder quickly retracts, and the rotary mechanism rotates in the opposite direction to work together to remove the jamming. For the three types of jamming conditions, different trigger thresholds and response strategies are formulated based on quantitative conditions such as pressure multiples and speed increase thresholds. For Type A (karst cave jamming), the feed and rotary anti-jamming mechanisms retract synchronously to quickly release the jamming from collapse. For Type B (gradually changing jamming), the speed is gradually adjusted to avoid equipment impact. For Type C (crack jamming), a powerful reverse retraction precisely addresses sudden jamming, improving operational efficiency and equipment protection in complex geological conditions in mountainous areas.

[0028] As a preferred technical approach: the feed cylinder has a single feed volume of 30-50mm, and the rotation angle of the revolution and rotation motor is 360 degrees. During the feeding and rotation process, the anti-jamming hydraulic system monitors the rotation pressure P1, hydraulic control pressure Pk, and overflow valve set pressure changes of the cutting head rotation motor in real time, dynamically responding to jamming conditions and triggering reversing and speed adjustment actions. By reducing the single cutting resistance, the probability of jamming is reduced, and with high-frequency pressure monitoring, jamming trends can be detected in a timely manner. The 360-degree rotation combined with real-time pressure monitoring allows for full-circumference cutting, ensuring that the rock around the foundation pit is cut evenly and thoroughly, avoiding cutting dead angles caused by insufficient rotation angle, and avoiding the risk of jamming at joints in traditional segmented operations. The dynamic response mechanism only triggers anti-jamming in abnormal situations, balancing anti-jamming effect and work efficiency, which is suitable for long-term and continuous operation scenarios in mountainous foundation excavation.

[0029] Beneficial Effects: By constructing a multi-layered anti-jamming system consisting of a feed anti-jamming hydraulic system, a rotary anti-jamming hydraulic system, and a cutting head anti-jamming structure, full-process, multi-dimensional anti-jamming protection is achieved. The feed anti-jamming hydraulic system monitors the difference between the rotary pressure of the cutting head's rotary motor and the hydraulic control pressure, enabling real-time response to drill jamming and control of the feed cylinder retraction during the feeding process. The rotary anti-jamming hydraulic system relies on the comparison between the rotary pressure of the cutting head's rotary motor and the pressure set by the overflow valve, triggering the rotary mechanism to retract in a timely manner during revolution and rotation. Both systems are adapted to different rock hardnesses through precise pressure control and flexible parameter adjustment, ensuring protection in diverse geological conditions such as caves, fissures, and gravel layers. The rotary drilling rig can quickly respond to various stuck drill conditions. The anti-jamming structure of the cutting head physically isolates rock powder through annular baffles or flanges, and uses water or airflow through spirally arranged nozzle channels to clear stuck and adhered mud and rocks, reducing the causes of stuck drills at the source. At the same time, the independent pressure and flow regulation capabilities provided by the three-oil pump series system, combined with the quantitative triggering mechanism and coordinated action strategy for three types of stuck drill conditions, as well as the design of small step feed and continuous rotation, greatly reduce the probability of stuck drills and processing time, reduce equipment wear, and improve operational safety and efficiency. It is perfectly adapted to the application requirements of modular equipment in mountainous areas and significantly enhances the adaptability and practicality of rotary drilling rigs in complex geological environments. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the working state of the hydraulic rotary drilling machine in this invention.

[0031] Figure 2 This is a schematic diagram illustrating the working principle of the anti-jamming feed in this invention.

[0032] Figure 3 This is a schematic diagram illustrating the working principle of the anti-jamming rotary mechanism of this invention.

[0033] Figure 4 This is a schematic diagram showing the location of the nozzle flow channel on the cutting head of the present invention.

[0034] In the diagram: 1. Upper platform; 2. Lower platform; 3. Rotary platform; 4. Reducer; 5. Cutting head; 6. Feed cylinder; 7. Revolutionary rotary motor; 8. First hydraulically controlled two-position four-way directional valve; 9. Pressure reducing valve; 10. Second hydraulically controlled two-position four-way directional valve; 11. Overflow valve; 12. Speed ​​regulating valve; 13. Cutting head rotary motor; 501. Spray nozzle; 502. Spray nozzle flow channel. Detailed Implementation

[0035] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings.

[0036] like Figures 1 to 4 As shown, a rotary drilling rig with multiple anti-jamming controls is disclosed. The rotary drilling rig includes an upper platform 1, a lower platform 2, a slewing bearing, a slewing platform 3, a reducer 4, a cutting head 5, a feed cylinder 6, guide columns, support legs, and a revolution and rotation motor 7. The rotary drilling rig is equipped with a multiple anti-jamming system, which includes a feed anti-jamming hydraulic system, a slewing anti-jamming hydraulic system, and an anti-jamming structure for the cutting head 5.

[0037] The feed anti-jamming hydraulic system is associated with the feed cylinder 6. By monitoring the difference between the rotation pressure of the cutting head rotary motor 13 and the hydraulic control pressure, the feed cylinder 6 is automatically reversed to remove the jam when the drill gets stuck during the feed of the cutting head 5. The feed anti-jamming hydraulic system includes a first hydraulic control two-position four-way reversing valve 8 and a pressure reducing valve 9.

[0038] The first control port of the first hydraulically controlled two-position four-way directional valve 8 is connected to the rotary pressure oil source of the cutting head 5, and the second control port is connected to the system pressure oil source through the pressure reducing valve 9. The pressure reducing valve 9 outputs hydraulic control pressure Pk.

[0039] The working port of the first hydraulically controlled two-position four-way directional valve 8 is connected to the feed cylinder 6.

[0040] When the rotational pressure P1 generated by the cutting head rotary motor 13 is less than or equal to Pk, the first hydraulically controlled two-position four-way directional valve 8 is in the left position, and the feed cylinder 6 feeds normally. When P1 > Pk, the first hydraulically controlled two-position four-way directional valve 8 reverses, and the feed cylinder 6 retracts to release the stuck drill. The feed anti-jamming hydraulic system uses the first hydraulically controlled two-position four-way directional valve 8 and the pressure reducing valve 9 to compare the rotational pressure P1 and the hydraulic control pressure Pk of the cutting head rotary motor 13 in real time.

[0041] The anti-jamming hydraulic system is associated with the revolution rotary motor 7. By monitoring the difference between the rotation pressure generated by the cutting head rotary motor 13 and the pressure set by the relief valve 11, the system automatically reverses the direction to control the rotation mechanism to retract and remove the jam when the drill gets stuck during the revolution of the cutting head 5. The anti-jamming hydraulic system includes a second hydraulically controlled two-position four-way reversing valve 10, a relief valve 11, and a speed regulating valve 12.

[0042] The first control port of the second hydraulic two-position four-way reversing valve 10 is connected to the rotary pressure oil source of the cutting head 5. The second control port of the second hydraulic two-position four-way reversing valve 10 is connected to the overflow valve 11 in sequence through the speed regulating valve 12. The other end of the overflow valve 11 is connected back to the oil tank.

[0043] The working port of the second hydraulic two-position four-way directional valve 10 is connected to the rotary mechanism driven by the revolution rotary motor 7;

[0044] When the rotation pressure P1 generated by the cutting head rotary motor 13 is less than or equal to the set pressure of the overflow valve 11, the second hydraulically controlled two-position four-way directional valve 10 is in the normal working position, and the revolution and rotation mechanism operates normally; when P1 is greater than the set pressure of the overflow valve 11, the second hydraulically controlled two-position four-way directional valve 10 reverses, and the rotation mechanism retracts to release the stuck drill.

[0045] The anti-jamming structure of the cutting head 5 includes an anti-fragmentation component and a nozzle flow channel 502 arranged circumferentially around the cutting head 5. The anti-rock fragmentation component is an annular baffle or flange arranged circumferentially around the cutting head 5 to prevent rock powder from entering the connection gap between the cutting head 5 and the drill pipe through a physical barrier, reducing the risk of mechanical jamming. The nozzle flow channel 502 has nozzles 501 arranged spirally on the outer circumferential surface of the cutting head 5, with the nozzle of each nozzle 501 located at the bottom of the nozzle flow channel 502, used to clear the stuck rock powder and mudstone through water or air flow.

[0046] The multi-layer anti-jamming system can handle three types of stuck drill conditions:

[0047] Type A stuck drill bit in a karst cave: When the cutting head 5 enters the cavity of the rock stratum and suddenly encounters the resistance of collapse, the rotation pressure P1 rises instantly and P1>1.2Pk, or 1.2 times the pressure set by the overflow valve 11. When the feed / rotation anti-jamming is triggered, the feed anti-jamming hydraulic system and the rotation anti-jamming hydraulic system are triggered to retract the cutter simultaneously, and the feed cylinder 6 retracts and the rotation mechanism retracts to remove the jamming.

[0048] Type B Gradual Jamming: When the cutting head 5 encounters progressively increasing resistance in the crack layer or gravel area, and the rotation pressure P1 continues to rise to P1 > 0.8Pk, or 0.8 times the set pressure of the relief valve 11 and the increase rate is ≥ 0.5MPa / s, the anti-jamming hydraulic system gradually reduces the feed speed of the feed cylinder 6 by slightly reversing the flow through the reversing valve or by finely adjusting the flow rate through the speed regulating valve 12 to reduce the rotation speed of the rotation mechanism until the resistance returns to normal.

[0049] Type C Crack Jamming: When the cutting head 5 suddenly jams due to a rock crack, the rotation pressure P1 rises sharply and P1 > 1.5Pk, or 1.5 times the pressure set by the overflow valve 11, the anti-jamming hydraulic system immediately triggers a reverse retraction action, the feed cylinder 6 quickly retreats, and the rotation mechanism rotates in the opposite direction to help remove the jamming.

[0050] For the above three types of stuck drill conditions, different trigger thresholds and coping strategies are formulated based on quantitative conditions such as pressure ratio and speed increase threshold. For type A stuck drill in karst caves, the feed and rotation anti-jamming are synchronized to quickly release the collapse and jamming. For type B stuck drill with gradual change, the speed is gradually adjusted to avoid equipment impact. For type C stuck drill in cracks, the drill is forcefully reversed to accurately deal with sudden jamming, improving the operation efficiency and equipment protection in complex geological conditions in mountainous areas.

[0051] To enhance flexibility in handling complex mountainous terrain, the rotary drilling rig's hydraulic system is a three-pump tandem system. The working pressure and flow rate of the cutting head (5), feed cylinder (6), and rotary motor (7) are independently adjustable. Specifically, the pressure regulating valve (9) of the feed anti-jamming hydraulic system and the pressure regulating valve (11) of the rotary anti-jamming hydraulic system achieve precise control through independent pressure branches of the three-pump tandem system, adapting to anti-jamming pressure requirements under different rock hardness conditions. Precise adjustment of various action parameters such as feed pressure and rotary speed enhances flexibility in handling complex mountainous terrain. An anomaly in one anti-jamming circuit does not affect other circuits, ensuring overall equipment stability and providing reliable power support for implementing anti-jamming strategies.

[0052] To adapt to different geological conditions such as soft and hard rock, the output pressure Pk of the pressure reducing valve 9 in the anti-jamming hydraulic system can be adjusted according to the rock hardness, with an adjustment range of 60%-80% of the system's working pressure. This adaptability allows for lowering Pk to increase anti-jamming sensitivity in soft rock and raising Pk to avoid false triggering in hard rock, enabling the equipment to intelligently adapt to the varied geological conditions of mountainous areas. When linked with a rock hardness sensor, it can also dynamically adjust parameters based on real-time geological changes. The hydraulic reversing logic is simple and reliable, resisting interference from harsh environments such as dust and vibration in mountainous areas, improving the equipment's versatility and stability under varying geological conditions, achieving fully automated intelligent operation, reducing manual intervention, and improving operational efficiency and accuracy.

[0053] To improve the reliability of equipment in complex geological conditions in mountainous areas, the set pressure of the relief valve 11 in the rotary anti-jamming hydraulic system can be adjusted according to the rock hardness, with an adjustment range of 70%-90% of the rated working pressure of the rotary motor 7. The speed control valve 12 is used to stabilize the control pressure of the relief valve 11. This ensures normal rotary power while triggering protection in time when the drill is stuck. The speed control valve 12 stabilizes the control pressure of the relief valve 11, suppresses pressure fluctuations, and ensures that the system responds stably under high-pressure impact, protecting the rotary motor and improving the reliability of the equipment in complex geological conditions in mountainous areas.

[0054] To better prevent jamming, the feed cylinder 6 has a single feed rate of 30-50mm, and the rotary motor 7 has a 360-degree rotation angle. During feeding and rotation, the anti-jamming hydraulic system monitors the rotation pressure P1 of the cutting head rotary motor 13, the hydraulic control pressure Pk, and the set pressure of the overflow valve 11 in real time, dynamically responding to jamming conditions and triggering reversing and speed adjustment actions. By reducing the resistance of a single cut, the probability of jamming is reduced. Combined with high-frequency pressure monitoring, jamming trends can be detected in a timely manner. The 360-degree rotation combined with real-time pressure monitoring allows for continuous full-circle cutting, avoiding the risk of jamming at joints in traditional segmented operations. The dynamic response mechanism only triggers anti-jamming in abnormal situations, balancing anti-jamming effectiveness and operational efficiency, which is suitable for long-term, continuous operations in mountainous foundation excavation scenarios.

[0055] The working process of a rotary drilling rig during foundation excavation in mountainous areas is as follows:

[0056] S1: After powering on, the equipment enters the work preparation state.

[0057] S2: Start the lower platform 2 support cylinder to support the machine body, and at the same time complete the center alignment to ensure the accurate operation position of the equipment.

[0058] S3: Release the upper platform 1 support cylinder to make room for the subsequent action of the feed cylinder 6.

[0059] S4: The feed cylinder 6 is pulled to its limit position to prepare for the cutting operation.

[0060] S5: Upper platform 1 is supported by hydraulic cylinders to stabilize the structure of upper platform 1.

[0061] S6: The lower platform 2 support cylinder is released, putting the equipment in a state where it can perform cutting operations.

[0062] S7: Cutting head 5 starts to rotate forward to cut the rock.

[0063] S8: Feed cylinder 6 initiates the feeding action, adjusting the feeding pressure according to the actual rock hardness conditions on site. The single feed amount is controlled between 30 and 50 mm. During this process, the anti-jamming hydraulic system operates continuously. This system monitors in real time the rotation pressure P1 generated by the cutting head rotary motor 13 and the hydraulic control pressure Pk output by the pressure reducing valve 9. Pk can be adjusted within 60%-80% of the system working pressure according to the rock hardness. When P1 ≤ Pk, the first hydraulic control two-position four-way directional valve 8 is in the left position, and feed cylinder 6 feeds normally. If a jamming tendency occurs, causing P1 > Pk, the first hydraulic control two-position four-way directional valve 8 immediately reverses, and feed cylinder 6 retracts to release the jamming. Normal feeding resumes after P1 returns to normal.

[0064] S9: After feeding is completed, the lower platform 2 support cylinder supports the machine body to ensure stability during rotation.

[0065] S10: The rotary motor rotates forward, adjusting the rotation pressure according to the actual rock hardness conditions on site, driving the cutting head 5 to complete a 360-degree cut until reaching the 360-degree limit position. During this process, the anti-jamming hydraulic system plays a role. This system monitors the pressure set by P1 and the relief valve 11. The pressure set by the relief valve 11 can be adjusted within 70%-90% of the rated working pressure of the rotary motor 7 according to the rock hardness. The speed control valve 12 controls the pressure fluctuation within ≤5%. When P1 ≤ the pressure set by the relief valve 11, the second hydraulically controlled two-position four-way directional valve 10 is in the normal working position, and the rotary motor 7 drives the rotary mechanism to operate normally. If a jamming occurs, causing P1 to exceed the pressure set by the relief valve 11, the second hydraulically controlled two-position four-way directional valve 10 reverses, the rotary mechanism retracts, and continues to rotate after P1 returns to normal until the 360-degree cut is completed and the limit position is reached.

[0066] S11: The revolution and rotation motor reverses, retracting the cutting head 5 to the 360-degree limit position.

[0067] S12: At this point, the first layer of the foundation pit has been cut off.

[0068] S13: Repeat steps S6 to S11, i.e., the lower platform 2 support cylinder is released, the cutting head 5 rotates forward to cut, the feed cylinder 6 with anti-jamming function feeds, the lower platform 2 support cylinder is supported, the revolution and rotation motor rotates forward to cut and reverses to retract, achieving layer-by-layer cutting downwards. Throughout the cutting process, the anti-jamming structure of the cutting head 5 continues to function: an annular baffle or flange is set along the circumference. In this embodiment, the height of the annular baffle or flange is ≥ twice the gap between the cutting head 5 and the drill pipe, preventing rock fragments from entering the gap. The nozzle flow channel 502 clears the stuck rock powder and fragments through the water flow or air flow of the nozzle 501, reducing the risk of drill jamming from a physical perspective.

[0069] S14: After completing several levels of cutting, the equipment stops drilling and a winch is used to lift the rock debris to the ground through the material bucket, clearing the rock debris from the pit.

[0070] S15: After completing one stroke of the feed cylinder 6, return to step S3, that is, the upper platform 1 support cylinder is released, and the next stroke begins.

[0071] S16: Repeat the above process to complete the required foundation pit depth.

[0072] Throughout the operation, the rotary drilling rig's three-pump tandem pump system ensures that the working pressure and flow rate of the cutting head 5 (rotation), feed cylinder 6 (feed), and revolution / rotation motor 7 can be independently adjusted. For different working conditions such as stuck drill bits in karst caves (Type A), gradually changing drill bits (Type B), and cracks (Type C), the multi-layered anti-jamming system monitors relevant pressure parameters in real time and coordinates strategies such as synchronous cutter retraction, gradual speed adjustment, and reverse cutter retraction to ensure the equipment completes excavation operations efficiently and safely.

[0073] By setting up multiple anti-jamming systems, integrating the feed anti-jamming hydraulic system, the slewing anti-jamming hydraulic system, and the cutting head 5 anti-jamming structure, a three-dimensional anti-jamming system covering the entire process of rotary drilling rig feeding, slewing, and cutting operations is constructed. The feed and slewing anti-jamming systems automatically respond to drill jamming based on pressure difference monitoring, while the cutting head 5 anti-jamming structure reduces rock powder jamming from a physical perspective. The three systems work together to effectively reduce the risk of drill jamming in complex geological conditions in mountainous areas, eliminating the need for frequent manual intervention, making it easy to promote in mountainous areas, and improving operational safety and efficiency.

[0074] The rotary drilling rig with multiple anti-jamming controls shown above is a specific embodiment of the present invention, which demonstrates the outstanding substantive features and significant progress of the present invention. Based on the actual use needs, equivalent modifications in shape, structure, etc., can be made to it according to the inspiration of the present invention, and all such modifications are within the scope of protection of this solution.

Claims

1. A rotary drilling rig with multiple anti-jamming controls, the rotary drilling rig comprising an upper platform, a lower platform, a slewing bearing, a slewing platform, a reducer, a cutting head, a feed cylinder, guide columns, support legs, and a revolution-rotation motor, characterized in that: The rotary drilling rig is equipped with a multi-layer anti-jamming system, which includes a feed anti-jamming hydraulic system, a slewing anti-jamming hydraulic system, and a cutting head anti-jamming structure. The aforementioned anti-jamming hydraulic system is associated with the feed cylinder. By monitoring the difference between the cutting head rotation pressure and the hydraulic control pressure, it automatically reverses the direction of the feed cylinder to remove the jam when the drill gets stuck during the cutting head feeding process. The aforementioned anti-jamming hydraulic system is associated with the revolution and revolution motor. By monitoring the difference between the rotation pressure of the cutting head and the pressure set by the overflow valve, it automatically reverses the direction and controls the rotation mechanism to retract and remove the jam when the drill gets stuck during the revolution and revolution of the cutting head. The aforementioned anti-jamming structure of the cutting head is used to physically isolate rock powder and clear stuck debris, including a nozzle channel arranged along the circumference of the cutting head; the nozzles of the nozzle channel are arranged in a spiral pattern on the outer circumference of the cutting head, and the nozzle of each nozzle is located at the bottom of the nozzle channel, which is used to clear stuck rock powder and debris by water or air flow. The aforementioned multi-layer anti-jamming system can handle three types of stuck drill conditions: Type A stuck drill bit in karst cave: When the cutting head suddenly encounters collapse resistance after entering the rock cavity, the rotation pressure P1 rises instantaneously and P1>1.2Pk, or 1.2 times the overflow valve setting pressure. When the feed / rotation anti-jamming is triggered, the feed anti-jamming hydraulic system and the rotation anti-jamming hydraulic system are triggered to retract the cutter simultaneously. The feed cylinder retracts and the rotation mechanism retracts to remove the jam. Type B Gradual Jamming: When the cutting head encounters progressively increasing resistance in the crack layer or gravel area, and the slewing pressure P1 continues to rise to P1 > 0.8Pk, or 0.8 times the set pressure of the relief valve and the increase rate is ≥ 0.5MPa / s, the anti-jamming hydraulic system gradually reduces the feed speed of the feed cylinder by slightly reversing the directional valve or by finely adjusting the flow rate of the slewing mechanism by the speed regulating valve until the resistance returns to normal. Type C Crack Jamming: When the cutting head suddenly jams due to a rock crack, the rotation pressure P1 rises sharply and P1 > 1.5Pk, or 1.5 times the pressure set by the relief valve, the anti-jamming hydraulic system immediately triggers a reverse retraction action, the feed cylinder quickly retracts, and the rotation mechanism rotates in the opposite direction to help remove the jamming.

2. The rotary excavating machine of claim 1 wherein: The feed anti-jamming hydraulic system includes a first hydraulically controlled two-position four-way directional valve and a pressure reducing valve; The first control port of the first hydraulically controlled two-position four-way directional valve is connected to the rotary pressure oil source of the cutting head, and the second control port is connected to the system pressure oil source through the pressure reducing valve. The pressure reducing valve outputs hydraulically controlled pressure Pk. The working port of the first hydraulically controlled two-position four-way directional valve is connected to the feed cylinder. When the rotary motor of the cutting head generates a rotary pressure P1≤Pk, the first hydraulically controlled two-position four-way directional valve is in the left position, and the feed cylinder feeds normally; when P1>Pk, the first hydraulically controlled two-position four-way directional valve reverses, and the feed cylinder retracts to release the stuck drill.

3. The rotary excavating machine of claim 2 wherein: The aforementioned anti-jamming hydraulic system includes a second hydraulically controlled two-position four-way directional valve, an overflow valve, and a speed control valve; The first control port of the second hydraulically controlled two-position four-way directional valve is connected to the rotary pressure oil source of the cutting head. The second control port of the second hydraulically controlled two-position four-way directional valve is connected to the overflow valve in sequence through the speed regulating valve. The other end of the overflow valve is connected back to the oil tank. The working port of the second hydraulically controlled two-position four-way directional valve is connected to the rotary mechanism driven by the revolution-rotation motor; When the rotational pressure P1 generated by the rotary motor of the cutting head is less than or equal to the set pressure of the overflow valve, the second hydraulically controlled two-position four-way directional valve is in the normal working position, and the revolution and rotation mechanism operates normally; when P1 is greater than the set pressure of the overflow valve, the second hydraulically controlled two-position four-way directional valve reverses, and the rotation mechanism retracts to release the stuck drill.

4. The rotary excavating machine of claim 3 wherein: The hydraulic system of the rotary drilling rig is a three-pump tandem pump system. The working pressure and flow rate of the cutting head rotation, feed cylinder feed, and revolution and rotation motor can be adjusted independently. Among them, the pressure adjustment of the pressure reducing valve of the feed anti-jamming hydraulic system and the pressure adjustment of the overflow valve of the rotation anti-jamming hydraulic system are both achieved by relying on the independent pressure branch of the three-pump tandem pump system to achieve precise control, adapting to the anti-jamming pressure requirements under different rock hardness.

5. The rotary excavating machine of claim 4 wherein: In the aforementioned feed anti-jamming hydraulic system, the output pressure Pk of the pressure reducing valve can be adjusted according to the rock hardness, with an adjustment range of 60%-80% of the system working pressure.

6. A rotary drilling rig with multiple anti-jamming controls according to claim 5, characterized in that: In the aforementioned rotary anti-jamming hydraulic system, the set pressure of the overflow valve can be adjusted according to the rock hardness, and the adjustment range is 70%-90% of the rated working pressure of the rotary motor. The speed regulating valve is used to stabilize the control pressure of the overflow valve.

7. A rotary drilling rig with multiple anti-jamming controls according to claim 6, characterized in that: The feed cylinder has a single feed amount of 30-50mm, and the rotation angle of the revolution and rotation motor is 360 degrees. During the feeding and rotation process, the anti-jamming hydraulic system monitors the rotation pressure P1, hydraulic control pressure Pk, and overflow valve set pressure changes of the cutting head rotation motor in real time, dynamically responds to the jamming condition, and triggers reversing and speed adjustment actions.

Images