Device and method for simulating eccentric ice core or rock core breaking process

Abstract

The present invention discloses a device and method for simulating the eccentric snapping process of ice cores or rock cores. The simulation device includes an operating table, a bracket, a motor, and a control system, wherein the bracket and the control system are both assembled on the operating table, the motor is disposed on the base of the bracket, the output shaft of the motor is connected to a screw, the top end of the screw is pivotally connected to an end cap below the top horizontal plate of the bracket, and the motor can drive the screw to rotate. The method comprises the following steps: step 1, assembling the simulation device; step 2, changing the angle of the snapping device; step 3, tightening the adjustment nut; step 4, bringing the snapping device close to the ice core or rock core; step 5, transmitting the data to a programmable logic controller (PLC); step 6, the snapping device continues to descend at a uniform speed; step 7, displaying a snapping force data curve on a snapping force display; and step 8, determining the quality of the ice core or rock core. Beneficial effects: The device can provide a basis for the design of reverse circulation continuous coring drill tools for polar ice layers and subglacial bedrock layers, as well as for the automatic equal-length snapping of ice cores or rock cores on site.

Description

Technical Field

[0001] The present invention relates to a device and method for simulating an eccentric snapping process, and in particular to a device and method for simulating an eccentric snapping process of an ice core or a rock core. Background Art

[0002] Currently, during mechanical coring drilling of polar ice and subglacial bedrock, operations such as pulling the drill bit to the surface to collect the ice or rock core after drilling a certain length of ice or rock core increase drilling assistance time and slow down drilling efficiency. During reverse circulation continuous coring drilling using double-wall drill pipe fluid (compressed air, cryogenic drilling fluid), the ice or rock core is broken by an eccentric breaking device and then circulated to the surface through the central channel of the drill bit inner tube with reverse circulation drilling fluid. This eliminates the need to lift the drill bit to collect the ice or rock core, greatly improving drilling efficiency. However, a certain amount of lateral displacement will occur during the breaking of the ice or rock core. The inner diameter of the drill bit inner tube should meet the spatial requirements for the lateral displacement of the ice or rock core, and the ice or rock core must be subjected to sufficient breaking force to generate lateral displacement during the breaking process. During the ice core or rock core breaking process, different drilling speeds, clamp angles, ice core or rock core diameters, and ice core or rock core lengths may have a significant impact on the lateral displacement, breaking force, and quality of the ice core or rock core. Therefore, it is particularly important to conduct in-depth research on the influencing mechanism. Summary of the Invention

[0003] The purpose of the present invention is to deeply study the eccentric breaking of ice cores or rock cores in reverse circulation continuous coring drilling of polar ice layers and subglacial bedrock layers, optimize and improve the eccentric breaking method of ice cores or rock cores, and the influence of different breaking speeds, breaking device angles, ice core or rock core diameters, ice core or rock core lengths on the ice core or rock core breaking time, lateral displacement generated during the ice core or rock core breaking process, ice core or rock core breaking force, ice core or rock core quality and other factors, and to provide a device and method for simulating the eccentric breaking process of ice cores or rock cores.

[0004] The ice core or rock core eccentric breaking process simulation device provided by the present invention includes an operating table, a bracket, a motor and a control system, wherein the bracket and the control system are both assembled on the operating table, the motor is arranged on the base of the bracket, the output shaft of the motor is connected to a screw, the top end of the screw is pivotally connected to the end cover below the top horizontal plate of the bracket, the motor can drive the screw to rotate according to a set frequency, and a sliding rod parallel to the screw is also provided on the bracket, an upper slider is screwed on the screw, and the other end of the upper slider is passed through the sliding rod, and during the rotation of the screw, the upper slider can be driven to slide up and down along the sliding rod, the outer end of the upper slider is pivotally connected to a ball head inclined rod, and the lower end of the ball head inclined rod is equipped with a clamp, and a specimen fixing hole is provided on the operating table corresponding to the position of the clamp, the ice core or rock core can be fixed in the specimen fixing hole, and a sensor is equipped on the clamp, and the sensor and the motor are both connected to the control system. The sensor can transmit the collected data to the control system in real time, and the control system provides power to the motor and controls the operation of the motor.

[0005] The motor is a servo motor.

[0006] The cam is secured to the upper and lower ends of the slide rails so that the slide rails can be adjusted to move upwards to move the slide rails, thereby reducing the risk of slipping and sliding the slide rails downwards.

[0007] The breaker at the lower end of the ball head inclined rod is a rectangular metal block. The sensor is assembled between the ball head inclined rod and the rectangular metal block through a side positioning plate. The ball head inclined rod and the sensor are coaxial and the axis passes through the center of the rectangular metal block and is perpendicular to the side with the largest area of ​​the rectangular metal block.

[0008] A hydraulic three-jaw chuck is installed under the operating table below the specimen fixing hole. The ice core or rock core inserted in the specimen fixing hole is fixed by the hydraulic three-jaw chuck. The hydraulic three-jaw chuck is connected to the control system, and the hydraulic three-jaw chuck is powered and controlled by the control system.

[0009] The control system includes a hydraulic three-jaw chuck control switch, a motor speed controller, a programmable logic controller (PLC), a breaking force display and a breaking time display, wherein the breaking force display and the breaking time display are both connected to the programmable logic controller (PLC). The hydraulic three-jaw chuck control switch is connected to the hydraulic three-jaw chuck, and the opening and closing of the hydraulic three-jaw chuck is controlled by the hydraulic three-jaw chuck control switch. The motor speed controller is connected to the motor, and the motor speed is controlled by the knob of the motor speed controller, thereby changing the rotation speed of the screw, driving the upper and lower sliders to descend synchronously and uniformly along the vertical direction of the slide bar, thereby adjusting the moving speed of the breaker. The breaking force display is also connected to the sensor, and the breaking force data collected by the sensor is received and displayed by the breaking force display, and then transmitted to the programmable logic controller (PLC). The programmable logic controller (PLC) can calculate the breaking time according to the input breaking force data through programming, and the programmable logic controller (PLC) then outputs the signal to the breaking time display so that the breaking time is displayed on the breaking time display. The control system is also equipped with an emergency stop switch, a power control switch and a power controller.

[0010] The above-mentioned motor, sensor, hydraulic three-jaw chuck, hydraulic three-jaw chuck control switch, motor speed controller, programmable logic controller PLC, breaking force display, breaking time display, emergency stop switch, power control switch and power controller are all assemblies of existing equipment, so the specific models and specifications are not repeated.

[0011] The present invention provides a method for simulating an eccentric ice core or rock core breaking process, the method comprising the following steps:

[0012] Step 1: After assembling the simulation device, select the diameter and length of the small diameter section of the ice core or rock core according to the designed experimental plan, clamp the large diameter section of the ice core or rock core with a hydraulic three-jaw chuck, and ensure that the upper end surface of the large diameter of the ice core or rock core is at the same level as the table surface of the operating table;

[0013] Step 2: Adjust the adjusting nuts on both sides of the L-shaped connecting rod head to change their position on the adjusting screw. As the L-shaped connecting rod moves horizontally, the trapezoidal nut slides in the ball head inclined rod slot, the inclination of the ball head inclined rod changes, and the angle of the clip changes;

[0014] Step 3: After the angle between the breaker and the horizontal line meets the experimental requirements, tighten the adjusting nuts on both sides of the L-shaped connecting rod head and tighten the trapezoidal nuts with bolts;

[0015] Step 4: Control the motor speed through the motor speed controller in the control system to drive the lead screw to rotate at a constant speed, driving the upper and lower sliders to descend synchronously and at a constant speed along the vertical direction of the slide bar, so that the clamping device moves toward the ice core or rock core at a constant speed according to the movement speed designed in the experimental plan;

[0016] Step 5: The breaker descends at a constant speed according to the designed experimental plan until it contacts the edge of the ice core or rock core. The sensor collects the force conditions of the ice core or rock core at this moment, displays it on the breaking force display, and transmits it to the programmable logic controller (PLC). The programmable logic controller (PLC) reads it and triggers the timing program in the programmable logic controller (PLC) to start timing.

[0017] Step 6: The breaker continues to descend at a constant speed, forcing the ice core or rock core to produce lateral displacement. As the displacement of the breaker increases, cracks appear at the bottom edge of the ice core or rock core, and the cracks gradually expand until they are completely broken.

[0018] Step 7: At the moment when the ice core or rock core is completely broken, the breaking force in the sensor disappears, and the timing program in the programmable logic controller (PLC) stops timing. The timing data is the breaking time of the ice core or rock core. The breaking time is then displayed on the breaking time display, and the breaking force data curve from the time when the breaking device contacts the edge of the ice core or rock core until the ice core or rock core is completely broken is displayed on the breaking force display;

[0019] Step 8: After the eccentric breaking of the ice core or rock core is completed, the integrity of the ice core or rock core and the damage on the surface are observed to determine the quality of the ice core or rock core obtained during the breaking process.

[0020] The working principle of the present invention is as follows:

[0021] The device and method for simulating the eccentric breaking process of ice cores or rock cores provided by the present invention use a hydraulic three-jaw chuck to clamp the bottom thick-diameter part of the ice core or rock core to be tested, whose diameter and length of the small-diameter section have been determined, and ensure that the upper end surface of the thick-diameter part is in the same horizontal plane as the table surface of the operating table, and the position of the L-shaped connecting rod on the adjusting screw is changed by adjusting the adjusting nuts on both sides of the head end of the L-shaped connecting rod. As the L-shaped connecting rod is horizontally displaced, the trapezoidal nut slides in the ball head inclined rod slide groove, and the inclination of the ball head inclined rod changes, so that the angle between the clamp and the horizontal line changes until the requirements of the experimental plan are met, and then the adjusting nuts on both sides of the head end of the L-shaped connecting rod are locked and the trapezoidal nuts are locked with bolts, and the motor speed is controlled by the motor speed controller to drive the screw to rotate at a uniform speed, driving the upper slider and the lower slider to synchronously descend at a uniform speed along the vertical direction of the slider, so that the clamp approaches the ice core or rock core at a uniform speed according to the movement speed designed in the experimental plan.

[0022] When the breaker contacts the edge of the ice core or rock core, the sensor collects the force conditions of the ice core or rock core at this moment, displays it on the breaking force display and transmits it to the programmable logic controller (PLC). The programmable logic controller (PLC) reads and triggers the timing program to start timing. The breaker continues to descend at a uniform speed, forcing the small diameter section of the ice core or rock core to produce lateral displacement, and cracks are generated at the bottom edge of the small diameter section of the ice core or rock core. As the displacement of the breaker increases, the cracks in the ice core or rock core continue to expand until it is completely broken. At the moment the ice core or rock core is completely broken, the breaking force in the sensor disappears, and the timing program in the programmable logic controller (PLC) stops timing. The timing data is the breaking time of the ice core or rock core and is displayed on the breaking time display. By analyzing and processing the measured data, the influence of different breaking speeds, breaker angles, ice core or rock core diameters and lengths on the breaking time is obtained. The vertical displacement of the clamp is determined by the relationship between the clamp speed and the clamp time. The lateral displacement of the top of the ice or rock core is then determined by the relationship between the vertical displacement of the clamp and the angle between the clamp and the horizontal line. The effects of different clamp speeds, clamp angles, ice or rock core diameters, and ice or rock core lengths on the lateral displacement caused by clamping are determined. A clamping force curve from the moment the clamp contacts the edge of the ice or rock core until the core is completely broken is displayed on a clamping force display. The peak of the clamping force curve represents the required clamping force. Comparative analysis of various experimental results reveals the effects of different clamp speeds, clamp angles, ice or rock core diameters, and ice or rock core lengths on the clamping force. The fracture characteristics of the ice or rock core are analyzed based on the trends in the clamping force curves, leading to the derivation of its mechanical properties. Furthermore, the clamping force curves at various clamp speeds are compared to determine the influence of clamping speed on the fracture characteristics of the ice or rock core. After the simulation experiment of the ice core or rock core breaking process is completed, the integrity of the broken ice core or rock core and the surface damage are observed, and the influence of the breaking speed, the angle of the breaker, the diameter of the ice core or rock core, and the length of the ice core or rock core on the quality of the ice core or rock core during the breaking process are obtained.

[0023] Beneficial effects of the present invention:

[0024] The device and method for simulating the eccentric snapping process of ice cores or rock cores provided by the present invention can fully simulate the eccentric snapping process of ice cores or rock cores in reverse circulation continuous coring drilling of polar ice layers and subglacial bedrock layers, and realize the adjustment of single or multiple variables in the snapping process. It can effectively evaluate the influence of the diameter, length, snapping speed and snapper angle of the ice core or rock core on the snapping time, lateral displacement, snapping force and quality of the ice core or rock core in the snapping process, and derive the optimal combination of ice core or rock core snapping parameters and the influence of the snapping speed on the fracture characteristics of the ice core or rock core under different working conditions. It can provide a basis for the design of reverse circulation continuous coring drill tools for polar ice layers and subglacial bedrock layers and the automatic equal-length snapping of ice cores or rock cores on site. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of the overall structure of the simulation device described in the present invention.

[0026] Figure 2 It is a schematic diagram of the local structure of the simulation device described in the present invention.

[0027] Figure 3 This is a structural schematic diagram of the ball head and oblique rod connection relationship described in the present invention.

[0028] Figure 4 This is a schematic diagram of the hydraulic three-jaw chuck described in the present invention.

[0029] Figure 5 The figure is a schematic diagram of the working principle of the control system of the present invention.

[0030] The annotations in the above figure are as follows:

[0031] 1. Operating table 2. Bracket 3. Motor 4. Control system 5. Lead screw 6. Slide rod

[0032] 7. Upper slider 8. Ball head inclined rod 9. Snap-off device 10. Specimen fixing hole 11. Sensor

[0033] 12. Slide 13. Trapezoidal nut 14. L-shaped connecting rod 15. Adjusting screw 16. Lower slider

[0034] 17. Adjusting nut 18. Connecting rod 19. Hydraulic three-jaw chuck 20. Hydraulic three-jaw chuck control switch

[0035] 21. Motor speed controller 22. Programmable logic controller (PLC) 23. Breaking force display

[0036] 24. Card break time display 25. Emergency stop switch 26. Power control switch

[0037] 27. Power controller. DETAILED DESCRIPTION

[0038] See also Figures 1 to 5 As shown:

[0039] The ice core or rock core eccentric snapping process simulation device provided by the present invention includes an operating table 1, a bracket 2, a motor 3 and a control system 4, wherein the bracket 2 and the control system 4 are both assembled on the operating table 1, the motor 3 is arranged on the base of the bracket 2, the output shaft of the motor 3 is connected to a screw 5, the top end of the screw 5 is pivotally connected to the end cover below the top horizontal plate of the bracket 2, the motor 3 can drive the screw 5 to rotate according to a set frequency, and the bracket 2 is further provided with a slide rod 6 parallel to the screw 5, an upper slider 7 is screwed on the screw 5, and the other end of the upper slider 7 is passed through the slide rod 6. During the rotation of the lead screw 5, the upper slider 7 can be driven to slide up and down along the slide rod 6. The outer end of the upper slider 7 is pivotally connected to a ball head inclined rod 8, and the lower end of the ball head inclined rod 8 is equipped with a clamp 9. A specimen fixing hole 10 is provided on the operating table 1 corresponding to the position of the clamp 9. The ice core or rock core can be fixed in the specimen fixing hole 10. The clamp 9 is equipped with a sensor 11. The sensor 11 and the motor 3 are both connected to the control system 4. The sensor 11 can transmit the collected data to the control system 4 in real time. The control system 4 provides power to the motor 3 and controls the operation of the motor 3.

[0040] Motor 3 is a servo motor.

[0041] The ball head inclined rod 8 is provided with a slide groove 12, and a trapezoidal nut 13 is clamped in the slide groove 12. The trapezoidal nut 13 can slide in the slide groove 12, and the outer end of the trapezoidal nut 13 is screwed with an L-shaped connecting rod 14. The head end of the L-shaped connecting rod 14 is screwed with the lower slider 16 through an adjusting screw 15. The adjusting screw 15 is passed through the head end of the L-shaped connecting rod 14, and the adjusting screws 15 on both sides of the head end of the L-shaped connecting rod 14 are respectively screwed with adjusting nuts 17. The position of the L-shaped connecting rod on the adjusting screw 15 is changed by moving the two adjusting nuts 17. The lower slider 16 is also passed through the slide rod 6. The upper end of the lower slider 16 is connected to the lower end of the upper slider 7 by a connecting rod 18. The action of the connecting rod 18 ensures that the lower slider 16 and the upper slider 7 slide synchronously on the slide rod 6.

[0042] The breaker 9 at the lower end of the ball head inclined rod 8 is a rectangular metal block, and the sensor 11 is assembled between the ball head inclined rod 8 and the rectangular metal block through the side positioning plate. The ball head inclined rod 8 and the sensor 11 are coaxial and the axis passes through the center of the rectangular metal block and is perpendicular to the side with the largest area of ​​the rectangular metal block.

[0043] A hydraulic three-jaw chuck 19 is installed under the operating table below the specimen fixing hole 10. The ice core or rock core inserted in the specimen fixing hole 10 is fixed by the hydraulic three-jaw chuck 19. The hydraulic three-jaw chuck 19 is connected to the control system 4. The hydraulic three-jaw chuck 19 is powered by the control system 4 and its operation is controlled by the control system 4.

[0044] The control system 4 includes a hydraulic three-jaw chuck control switch 20, a motor speed controller 21, a programmable logic controller PLC22, a card breaking force display 23 and a card breaking time display 24, wherein the card breaking force display 23 and the card breaking time display 24 are both connected to the programmable logic controller PLC22, the hydraulic three-jaw chuck control switch 20 is connected to the hydraulic three-jaw chuck 19, and the opening and closing of the hydraulic three-jaw chuck 19 is controlled by the hydraulic three-jaw chuck control switch 20, the motor speed controller 21 is connected to the motor 3, and the speed of the motor 3 is controlled by the knob of the motor speed controller 21, thereby changing the rotation speed of the screw 5, driving the upper slider 7 and the lower slider 7. Block 16 descends synchronously and uniformly in the vertical direction of the slide bar 6, thereby adjusting the moving speed of the breaker 9. The breaking force display 23 is also connected to the sensor 11. The breaking force data collected by the sensor 11 is received and displayed by the breaking force display 23, and then transmitted to the programmable logic controller PLC22. The programmable logic controller PLC22 can calculate the breaking time according to the input breaking force data through programming. The programmable logic controller PLC22 then outputs the signal to the breaking time display 24, so that the breaking time is displayed on the breaking time display 24. The control system 4 is also equipped with an emergency stop switch 25, a power control switch 26 and a power controller 27.

[0045] The above-mentioned motor 3, sensor 11, hydraulic three-jaw chuck 19, hydraulic three-jaw chuck control switch 20, motor speed controller 21, programmable logic controller PLC22, breaking force display 23, breaking time display 24, emergency stop switch 25, power control switch 26 and power controller 27 are all assemblies of existing equipment, so the specific models and specifications are not repeated.

[0046] The present invention provides a method for simulating an eccentric ice core or rock core breaking process, the method comprising the following steps:

[0047] Step 1: After assembling the simulation device, select the diameter and length of the small diameter section of the ice core or rock core according to the designed experimental plan, clamp the large diameter section of the ice core or rock core with the hydraulic three-jaw chuck 19, and ensure that the upper end surface of the large diameter of the ice core or rock core is at the same level as the table surface of the operating table 1;

[0048] Step 2: Adjust the adjusting nuts 17 on both sides of the head end of the L-shaped connecting rod 14 to change its position on the adjusting screw 15. As the L-shaped connecting rod 14 moves horizontally, the trapezoidal nut 13 slides in the slide groove 12 of the ball head inclined rod 8, the inclination of the ball head inclined rod 8 changes, and the angle of the clip 9 changes;

[0049] Step 3: After the angle between the breaker 9 and the horizontal line reaches the experimental requirement, tighten the adjusting nuts 17 on both sides of the head end of the L-shaped connecting rod 14 and tighten the trapezoidal nuts 13 with bolts;

[0050] Step 4: Control the speed of the motor 3 through the motor speed controller 21 in the control system 4, drive the screw 5 to rotate at a constant speed, drive the upper slider 7 and the lower slider 16 to descend synchronously at a constant speed along the vertical direction of the slide bar 6, and make the clamp 9 move at a constant speed close to the ice core or rock core according to the movement speed designed in the experimental plan;

[0051] Step 5: The breaker 9 is lowered at a constant speed according to the designed experimental plan until it contacts the edge of the ice core or rock core. The sensor 11 collects the force conditions of the ice core or rock core at this moment, displays them on the breaking force display 23 and transmits them to the programmable logic controller PLC22. The programmable logic controller PLC22 reads and triggers the timing program in the programmable logic controller PLC22 to start timing.

[0052] Step 6: The breaker 9 continues to descend at a constant speed, forcing the ice core or rock core to produce lateral displacement. As the displacement of the breaker 9 increases, cracks are generated at the bottom edge of the ice core or rock core, and the cracks gradually expand until they are completely broken.

[0053] Step 7: At the moment when the ice core or rock core is completely broken, the breaking force in the sensor 11 disappears, and the timing program in the programmable logic controller PLC22 stops timing. The timing data is the breaking time of the ice core or rock core. The breaking time is then displayed on the breaking time display 24, and the breaking force data curve of the time when the breaker 9 contacts the edge of the ice core or rock core until the ice core or rock core is completely broken is displayed on the breaking force display 23;

[0054] Step 8: After the eccentric breaking of the ice core or rock core is completed, the integrity of the ice core or rock core and the damage on the surface are observed to determine the quality of the ice core or rock core obtained during the breaking process.

[0055] The working principle of the present invention is as follows:

[0056] The device and method for simulating the eccentric breaking process of an ice core or a rock core provided by the present invention uses a hydraulic three-jaw chuck 19 to clamp the bottom thick-diameter portion of the ice core or rock core to be tested, whose diameter and length of the small-diameter section have been determined, and ensures that the upper end surface of the thick-diameter portion is at the same horizontal plane as the table surface of the operating table 1. By adjusting the adjusting nuts 17 on both sides of the head end of the L-shaped connecting rod 14, the position of the L-shaped connecting rod 14 on the adjusting screw 15 is changed. As the L-shaped connecting rod 14 moves horizontally, the trapezoidal nut 13 slides on the ball head inclined rod 8. The ball head slides in the groove 12, and the inclination of the inclined rod 8 changes, so that the angle between the breaker 9 and the horizontal line changes until it meets the requirements of the experimental plan. Then, the adjusting nuts 17 on both sides of the head end of the L-shaped connecting rod 14 are locked and the trapezoidal nuts 13 are locked with bolts. The speed of the motor 3 is controlled by the motor speed controller 21, and the screw 5 is driven to rotate at a constant speed, driving the upper slider 7 and the lower slider 16 to descend synchronously at a constant speed in the vertical direction of the slide bar 6, so that the breaker 9 approaches the ice core or rock core at a constant speed according to the movement speed designed in the experimental plan.

[0057] When the breaker 9 contacts the edge of the ice core or rock core, the sensor 11 collects the stress conditions of the ice core or rock core at this moment, displays it on the breaking force display 23 and transmits it to the programmable logic controller PLC22. The programmable logic controller PLC22 reads and triggers the timing program to start timing. The breaker 9 continues to descend at a uniform speed, forcing the small diameter section of the ice core or rock core to produce lateral displacement, and cracks are generated at the bottom edge of the small diameter section of the ice core or rock core. As the displacement of the breaker 9 increases, the cracks in the ice core or rock core continue to expand until it is completely broken. At the moment the ice core or rock core is completely broken, the breaking force in the sensor 11 disappears, and the timing program in the programmable logic controller PLC22 stops timing. The timing data is the breaking time of the ice core or rock core and is displayed on the breaking time display 24. By analyzing and processing the measured data, the influence of different breaking speeds, breaker 9 angles, ice core or rock core diameters and lengths on the breaking time is obtained. The vertical displacement of the breaker 9 is determined by the relationship between the breaking speed and the breaking time. The lateral displacement of the top of the ice core or rock core is then determined by the relationship between the vertical displacement of the breaker 9 and the angle between the breaker 9 and the horizontal line. The effects of different breaking speeds, the angle of the breaker 9, the diameter of the ice core or rock core, and the length of the ice core or rock core on the lateral displacement caused by the breaking are determined. A breaking force data curve from the entire process from the contact of the breaker 9 with the edge of the ice core or rock core to the complete breaking of the ice core or rock core is displayed on the breaking force display 23. The peak of the breaking force data curve is the required breaking force of the ice core or rock core. By comparing and analyzing various experimental results, the effects of different breaking speeds, the angle of the breaker 9, the diameter of the ice core or rock core, and the length of the ice core or rock core on the breaking force of the ice core or rock core are determined. The fracture characteristics of the ice core or rock core are analyzed based on the changing trends of the breaking force data curves, and their mechanical properties are determined. The breaking force data curves at various breaking speeds are also compared to determine the effect of the breaking speed on the fracture characteristics of the ice core or rock core. After the simulation experiment of the ice core or rock core breaking process is completed, the integrity of the broken ice core or rock core and the surface damage are observed, and the influence of the breaking speed, the angle of the breakers, the diameter of the ice core or rock core, and the length of the ice core or rock core on the quality of the ice core or rock core during the breaking process are obtained.

Claims

1. A device for simulating the eccentric breaking process of an ice core or rock core, characterized by: The machine comprises an operating table, a bracket, a motor and a control system, wherein the bracket and the control system are both assembled on the operating table, the motor is arranged on the base of the bracket, the output shaft of the motor is connected to a lead screw, the top end of the lead screw is pivotally connected to the end cover below the top horizontal plate of the bracket, the motor can drive the lead screw to rotate at a set frequency, and the bracket is also provided with a sliding rod parallel to the lead screw, the lead screw is screwed with an upper slider, the other end of the upper slider is passed through the sliding rod, and the lead screw can drive the upper slider to slide up and down along the sliding rod during rotation, the outer end of the upper slider is pivotally connected to a ball head inclined rod, the lower end of the ball head inclined rod is equipped with a clamp, a specimen fixing hole is provided on the operating table corresponding to the position of the clamp, the specimen fixing hole can fix an ice core or a rock core, the clamp is equipped with a sensor, the sensor and the motor are both connected to the control system, the sensor can transmit the collected data to the control system in real time, the control system provides power to the motor and controls the operation of the motor.

2. The device for simulating eccentric ice or rock core breaking according to claim 1, characterized in that: The motor is a servo motor.

3. The device for simulating eccentric ice or rock core breaking according to claim 1, characterized in that: The cam is secured to the upper and lower ends of the slide rails and is designed to be adjusted to allow the slide rails to slide in the opposite direction of the slide rails, thereby ensuring that the slide rails are in a stable position relative to each other.

4. The device for simulating eccentric ice or rock core breaking according to claim 1, characterized in that: The breaker at the lower end of the ball head inclined rod is a rectangular metal block. The sensor is assembled between the ball head inclined rod and the rectangular metal block through a side positioning plate. The ball head inclined rod and the sensor are coaxial and the axis passes through the center of the rectangular metal block and is perpendicular to the side with the largest area of ​​the rectangular metal block.

5. The device for simulating eccentric ice or rock core breaking according to claim 1, characterized in that: A hydraulic three-jaw chuck is installed under the operating table below the specimen fixing hole. The ice core or rock core inserted in the specimen fixing hole is fixed by the hydraulic three-jaw chuck. The hydraulic three-jaw chuck is connected to the control system, and the hydraulic three-jaw chuck is powered by the control system and controlled by the control system.

6. The device for simulating eccentric ice or rock core breaking according to claim 1, 4 or 5, characterized in that: The control system includes a hydraulic three-jaw chuck control switch, a motor speed controller, a programmable logic controller (PLC), a breaking force display and a breaking time display, wherein the breaking force display and the breaking time display are both connected to the programmable logic controller (PLC), the hydraulic three-jaw chuck control switch is connected to the hydraulic three-jaw chuck, and the opening and closing of the hydraulic three-jaw chuck is controlled by the hydraulic three-jaw chuck control switch, the motor speed controller is connected to the motor, and the motor speed is controlled by the knob of the motor speed controller, thereby changing the rotation speed of the screw, driving the upper slider and the lower slider to descend synchronously and uniformly along the vertical direction of the slide bar, thereby adjusting the moving speed of the breaker, the breaking force display is also connected to the sensor, and the breaking force display receives and displays the breaking force data collected by the sensor, and then transmits it to the programmable logic controller (PLC), the programmable logic controller (PLC) can calculate the breaking time according to the input breaking force data through programming, and the programmable logic controller (PLC) then outputs the signal to the breaking time display so that the breaking time is displayed on the breaking time display. The control system is also equipped with an emergency stop switch, a power control switch and a power controller.

7. A method for simulating the eccentric breaking process of an ice core or rock core, characterized by: The method includes the following steps: Step 1: After assembling the simulation device, select the diameter and length of the small diameter section of the ice core or rock core according to the designed experimental plan, clamp the large diameter section of the ice core or rock core with a hydraulic three-jaw chuck, and ensure that the upper end surface of the large diameter of the ice core or rock core is at the same level as the table surface of the operating table; Step 2: Adjust the adjusting nuts on both sides of the L-shaped connecting rod head to change their position on the adjusting screw. As the L-shaped connecting rod moves horizontally, the trapezoidal nut slides in the ball head inclined rod slot, the inclination of the ball head inclined rod changes, and the angle of the clip changes; Step 3: After the angle between the breaker and the horizontal line meets the experimental requirements, tighten the adjusting nuts on both sides of the L-shaped connecting rod head and tighten the trapezoidal nuts with bolts; Step 4: Control the motor speed through the motor speed controller in the control system to drive the lead screw to rotate at a constant speed, driving the upper and lower sliders to descend synchronously and at a constant speed along the vertical direction of the slide bar, so that the clamping device moves toward the ice core or rock core at a constant speed according to the movement speed designed in the experimental plan; Step 5: The breaker descends at a constant speed according to the designed experimental plan until it contacts the edge of the ice core or rock core. The sensor collects the force conditions of the ice core or rock core at this moment, displays it on the breaking force display, and transmits it to the programmable logic controller (PLC). The programmable logic controller (PLC) reads it and triggers the timing program in the programmable logic controller (PLC) to start timing. Step 6: The breaker continues to descend at a constant speed, forcing the ice core or rock core to produce lateral displacement. As the displacement of the breaker increases, cracks appear at the bottom edge of the ice core or rock core, and the cracks gradually expand until they are completely broken. Step 7: At the moment when the ice core or rock core is completely broken, the breaking force in the sensor disappears, and the timing program in the programmable logic controller (PLC) stops timing. The timing data is the breaking time of the ice core or rock core. The breaking time is then displayed on the breaking time display, and the breaking force data curve from the time when the breaking device contacts the edge of the ice core or rock core until the ice core or rock core is completely broken is displayed on the breaking force display; Step 8: After the eccentric breaking of the ice core or rock core is completed, the integrity of the ice core or rock core and the damage on the surface are observed to determine the quality of the ice core or rock core obtained during the breaking process.

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