Experimental device for impact wear resistance of lining plate of semi-autogenous mill

Abstract

The invention relates to an experimental device for the impact and wear resistance of a semi-autogenous mill lining plate, which comprises a lifting device, a ball falling device, an inclined test block and a vibration feeder, and is an impact and wear resistance experimental device capable of really simulating the actual service condition of the semi-autogenous mill lining plate. The combined action of steel balls and grinding materials in the semi-autogenous mill can be truly represented, composite abrasion simulation of steel ball impact, sliding abrasion and grinding material flowing action is achieved through the multifunctional integrated design of the device, the steel balls and the grinding materials can be recycled through an inclined ball recycling baffle, a complex mechanical pushing device is not needed, and the device is simple in structure and convenient to operate. Through combination of the force sensor and the laser scanner, high-precision impact and abrasion data are provided, result analysis is facilitated, impact energy, impact frequency, inclination angle and dynamic displacement speed can be flexibly adjusted, various experiment requirements are met, and a scientific basis is provided for model selection and optimization of lining plate materials.

Description

Technical Field

[0001] The present invention relates to the field of performance experimental devices for semi-autogenous mill liners, and particularly to an experimental device for the impact and wear resistance performance of semi-autogenous mill liners. Background Art

[0002] With the trend of large-scale development of global mining equipment, ultra-large-sized mills have also developed rapidly. As a core device, large semi-autogenous mills have the characteristics of impact crushing and grinding, and can efficiently process various minerals with different hardnesses. As a key component and key spare part of large mining equipment, the liner lifts the minerals and grinding media to make them rub and collide with each other, thereby crushing and grinding the minerals, and at the same time protecting the mill itself from damage by the minerals and grinding media. In the past 30 years, due to the continuous progress of mill design theory and mill manufacturing technology, the mill specifications have been continuously broken through, gradually developing from a diameter of φ5m to more than φ10m. As of now, the largest semi-autogenous mill in operation globally has reached a specification of φ12.2×7.6m. With the increase in the size of the semi-autogenous mill, the throwing potential energy of the grinding balls increases significantly, and the impact force on the liner is greatly enhanced, resulting in the liner of the ultra-large semi-autogenous mill being prone to fracture and insufficient wear resistance during service.

[0003] The impact and wear resistance performance of the liner is a key indicator for evaluating the quality of the liner material. Therefore, it is necessary to conduct simulation experiments on impact and wear through a test device. However, the existing test devices have various defects. Usually, they can only test the impact of steel balls or the sliding wear of abrasives alone, and cannot effectively reproduce the combined action of the two. It is difficult to simulate the dynamic relative displacement generated by the steel balls and abrasives on the liner surface, and there are significant deviations between the experimental results and the actual working conditions. Summary of the Invention

[0004] The purpose of the present invention is to provide an experimental device for the impact and wear resistance performance of semi-autogenous mill liners, which realizes the combined simulation of impact, sliding, and rolling wear.

[0005] The technical solution adopted by the present invention to solve the above technical problems is: an experimental device for the impact and wear resistance performance of semi-autogenous mill liners, including a lifting device, a ball dropping device, an inclined test block, and a vibrating feeder. The lifting device can drive the steel balls to move upward. The ball dropping device is installed at the ball outlet at the top of the lifting device. The bottom side of the ball dropping device is provided with an electromagnetic release mechanism, and the electromagnetic release mechanism can continuously switch between an open state and a closed state, so that multiple steel balls can fall from the ball dropping device in sequence at a fixed frequency. The inclined test block is installed on a dynamic stage. The upper surface of the inclined test block is an inclined plane for colliding with the dropped steel balls. The dynamic stage can drive the inclined test block to reciprocate horizontally. The discharge port of the vibrating feeder is located above the inclined plane of the inclined test block, and the vibrating feeder can make the material fall to the top of the inclined plane of the inclined test block. Two ball collecting baffles are provided on both sides of the inclined test block and the dynamic stage. The two ball collecting baffles are symmetrically and inclinedly arranged. The edges of the two ball collecting baffles on the side away from each other are higher than the bottom end of the inclined surface of the inclined test block, and the edges of the two ball collecting baffles on the side close to each other are lower than the bottom end of the inclined surface of the inclined test block. There is a gap with a width smaller than the diameter of the steel ball between the edges of the two ball collecting baffles on the side close to each other. An abrasive recovery tank is provided below the two ball collecting baffles, so that the two ball collecting baffles can cooperate to receive the steel balls sliding down from the bottom end of the inclined surface of the inclined test block, and the abrasive sliding down from the bottom end of the inclined surface of the inclined test block can fall into the abrasive recovery tank. The edges of the two ball collecting baffles on the side close to each other are also docked with one end of the ball return groove, and the other end of the ball return groove is connected to the bottom inlet of the lifting device; A force sensor is provided on the bottom side of the inclined test block. The force sensor can monitor the impact force of the steel ball on the inclined test block. A laser scanner is also provided on one side of the inclined test block. The laser scanner can scan the inclined surface of the inclined test block, so as to record the wear depth and volume of the inclined test block.

[0006] Preferably, the lifting device is a bucket elevator or a screw elevator.

[0007] Preferably, the inclination angle of the inclined test block is 10°-35°.

[0008] Preferably, the inclined test block is installed on the dynamic stage through a support fixture. The inclination angle of the inclined test block can be adjusted through the support fixture. The horizontal movement speed of the dynamic stage driving the inclined test block is 1-10m / s, and the horizontal movement distance range is 10-50mm.

[0009] Preferably, the abrasive recovery tank can convey the materials to the screening device, and a circulating conveying device is provided between the screening device and the vibrating feeder, which can convey the screened materials to the vibrating feeder.

[0010] According to the above technical solution, the beneficial effects of the present invention are: The present invention can truly simulate the anti-impact wear test device for the actual service conditions of the semi-autogenous mill liner. The inclined test block is combined with the design of the dynamic stage, which can truly reproduce the combined action of steel balls and abrasives in the semi-autogenous mill. Through the multi-functional integrated design of the device, the composite wear simulation of steel ball impact, sliding wear and abrasive flow action is realized. The steel balls and abrasives can be recycled through the inclined ball collecting baffles without a complex mechanical pushing device. By combining the force sensor and the laser scanner, high-precision impact and wear data are provided for easy result analysis. The impact work, impact frequency, inclination angle and dynamic displacement speed can all be flexibly adjusted to adapt to various experimental requirements, providing a scientific basis for the selection and optimization of liner materials. Description of the Drawings

[0011] Figure 1 It is a schematic diagram of the present invention.

[0012] Markings in the figure: 1. Lifting device, 2. Ball dropping device, 3. Inclined test block, 4. Ball receiving baffle, 5. Ball return groove. Specific implementation mode

[0013] Referring to the attached drawings, the specific implementation mode is as follows: An experimental device for the impact wear resistance of a semi-autogenous mill liner, comprising a lifting device 1, a ball dropping device 2, an inclined test block 3 and a vibrating feeder. The lifting device 1 is a bucket elevator or a screw elevator, which can drive the steel balls to move upward. The ball dropping device 2 is installed at the ball outlet at the top end of the lifting device 1. An electromagnetic release mechanism is provided at the bottom opening of the ball dropping device 2, and the electromagnetic release mechanism can continuously switch between an open state and a closed state, so that multiple steel balls can fall from the ball dropping device 2 in sequence at a fixed frequency.

[0014] The inclined test block 3 is installed on a dynamic stage. The upper surface of the inclined test block 3 is an inclined plane with an inclination angle of 10° - 35°, which is used to collide with the falling steel balls. The dynamic stage can drive the inclined test block 3 to reciprocate horizontally. The outlet of the vibrating feeder is located above the inclined plane of the inclined test block 3, and the vibrating feeder can make the material fall to the top end of the inclined plane of the inclined test block 3. The inclined test block 3 is installed on the dynamic stage through a support fixture, and the inclination angle of the inclined test block 3 can be adjusted through the support fixture. The horizontal movement speed of the dynamic stage driving the inclined test block 3 is 1 - 10 m / s, and the horizontal movement distance range is 10 - 50 mm. The vibration direction of the vibrating feeder is the same as the horizontal movement direction of the inclined test block 3.

[0015] Two ball receiving baffles 4 are provided on both sides of the inclined test block 3 and the dynamic stage. The two ball receiving baffles 4 are symmetrically inclined. The edges on the side where the two ball receiving baffles 4 are away from each other are higher than the bottom end of the inclined plane of the inclined test block 3, and the edges on the side where the two ball receiving baffles 4 are close to each other are lower than the bottom end of the inclined plane of the inclined test block 3. And there is a gap with a width smaller than the diameter of the steel ball between the edges on the side where the two ball receiving baffles 4 are close to each other. A grinding material recovery tank is provided below the two ball receiving baffles 4, so that the two ball receiving baffles 4 can cooperate to receive the steel balls sliding down from the bottom end of the inclined plane of the inclined test block 3, and the grinding material sliding down from the bottom end of the inclined plane of the inclined test block 3 can fall into the grinding material recovery tank.

[0016] The edges on the side where the two ball receiving baffles 4 are close to each other are also docked with one end of the ball return groove 5, and the other end of the ball return groove 5 is connected to the bottom ball inlet of the lifting device 1. The grinding material recovery tank can convey the material to a screening device, and a circulating conveying device is provided between the screening device and the vibrating feeder, which can convey the screened material to the vibrating feeder.

[0017] A force sensor is provided on the bottom side of the inclined test block 3. The force sensor can monitor the impact force of the steel ball on the inclined test block 3. A laser scanner is also provided on one side of the inclined test block 3. The laser scanner can scan the inclined surface of the inclined test block 3 to record the wear depth and volume of the inclined test block 3.

[0018] The working process of this embodiment is as follows: First, install the inclined test block 3 on the dynamic loading platform and adjust the inclination angle and horizontal movement parameters. After the steel ball is lifted by the lifting device 1 and freely falls, it impacts the surface of the inclined test block 3, then falls onto the ball receiving baffle 4, and finally returns to the lifting device 1 through the ball return groove 5. At the same time, the abrasive is scattered onto the top of the test block by the vibrating feeder and moves synchronously with the dynamic loading platform to simulate the sliding and rolling effects of the abrasive in the real working condition. The reciprocating movement of the inclined test block dynamic loading platform is perpendicular to the impact direction of the steel ball, forming a combined action of impact, sliding, and rolling wear. The steel balls continuously impact the inclined test block 3 according to the required frequency by adjusting the switching frequency of the electromagnetic release mechanism.

[0019] During the experiment, the force sensor continuously collects impact force data and scans the inclined surface of the inclined test block 3 through laser scanning to generate a three-dimensional wear morphology of the inclined test block 3. The laser scanner is installed on a rigid support independent of the dynamic loading platform during shutdown. The support is directly fixed to the ground and has no rigid connection with the drive mechanism of the dynamic loading platform to avoid the influence of vibration on the laser instrument during the experiment. Finally, the data processing system automatically separates the wear area and calculates the normal wear depth by curvature filtering and fitting with the reference plane, and calculates the wear volume. The specific steps are as follows: 1. Laser scanning Initial reference scanning: Before the experiment, perform high-density scanning on the surface of the test block to generate the original three-dimensional point cloud model; Periodic interval scanning: Pause the experiment after each set number of impacts and perform rapid scanning; Termination scanning: After the experiment ends, perform full-resolution scanning and compare with the initial model to calculate the cumulative wear amount.

[0020] 2. Algorithm process: Through the curvature filtering and region growing algorithms, automatically extract the boundary of the wear pit from the point cloud, fit the reference plane of the unworn area based on random sample consensus, and calculate the normal distance from each point to the reference plane as the local wear depth.

[0021] 3. Wear volume calculation model: ; where d i is the wear depth of the i-th grid cell; S i is the projected area of the grid cell; Convert the point cloud data into a regular grid and calculate the volume loss of each grid cell.

[0022] The test device of this embodiment can reproduce the wear behavior under the actual working conditions of the semi-autogenous mill, has the advantages of simple structure, convenient operation and reliable data, and is suitable for the study of the impact wear resistance of liner materials.

Claims

1. An experimental device for the impact wear resistance performance of a semi-autogenous mill liner, characterized in that: It includes a lifting device (1), a ball dropping device (2), an inclined test block (3) and a vibrating feeder. The lifting device (1) can drive the steel balls to move upward. The ball dropping device (2) is installed at the ball outlet at the top of the lifting device (1). The bottom side opening of the ball dropping device (2) is provided with an electromagnetic release mechanism, which can continuously switch between the open state and the closed state, so that multiple steel balls can fall from the ball dropping device (2) in sequence at a fixed frequency. The inclined test block (3) is installed on a dynamic stage. The upper surface of the inclined test block (3) is an inclined plane for colliding with the falling steel balls. The dynamic stage can drive the inclined test block (3) to reciprocate horizontally. The discharge port of the vibrating feeder is located above the inclined plane of the inclined test block (3), and the vibrating feeder can make the material fall to the top of the inclined plane of the inclined test block (3); Two ball collecting baffles (4) are provided on both sides of the inclined test block (3) and the dynamic stage. The two ball collecting baffles (4) are symmetrically inclined. The edges of the two ball collecting baffles (4) on the side away from each other are higher than the bottom end of the inclined plane of the inclined test block (3). The edges of the two ball collecting baffles (4) on the side close to each other are lower than the bottom end of the inclined plane of the inclined test block (3). And there is a gap with a width smaller than the diameter of the steel ball between the edges of the two ball collecting baffles (4) on the side close to each other. A grinding abrasive recovery tank is provided below the two ball collecting baffles (4), so that the two ball collecting baffles (4) can cooperate to receive the steel balls sliding down from the bottom end of the inclined plane of the inclined test block (3), and make the grinding abrasive sliding down from the bottom end of the inclined plane of the inclined test block (3) fall into the grinding abrasive recovery tank. The edges of the two ball collecting baffles (4) on the side close to each other are also docked with one end of a ball return groove (5), and the other end of the ball return groove (5) is connected to the bottom ball inlet of the lifting device (1); A force sensor is provided on the bottom side of the inclined test block (3), which can monitor the impact force of the steel ball on the inclined test block (3). A laser scanner is also provided on one side of the inclined test block (3), which can scan the inclined plane of the inclined test block (3) to record the wear depth and volume of the inclined test block (3).

2. The experimental device for the impact wear resistance performance of the semi-autogenous mill liner according to claim 1, wherein: The lifting device (1) is a bucket elevator or a screw elevator.

3. The experimental device for the impact wear resistance performance of the semi-autogenous mill liner according to claim 1, characterized in that: The inclination angle of the inclined test block (3) is 10° - 35°.

4. An experimental device for the impact wear resistance performance of a semi-autogenous mill liner according to claim 3, characterized in that: The inclined test block (3) is installed on the dynamic stage through a support fixture. The inclination angle of the inclined test block (3) can be adjusted through the support fixture. The horizontal movement speed of the dynamic stage driving the inclined test block (3) is 1 - 10 m / s, and the horizontal movement distance range is 10 - 50 mm.

5. The experimental device for the impact wear resistance performance of the semi-autogenous mill liner according to claim 1, characterized in that: The grinding abrasive recovery tank can convey the material to a screening device, and a circulating conveying device is provided between the screening device and the vibrating feeder, which can convey the screened material to the vibrating feeder.

Images