High precision 3D measurement of overturning dynamic trajectory of car dumper realized by radial laser tracker + at moving target

Dumper & Workflow

Car dumper is widely used in port, metallurgy, coal, thermal power and other industrial departments with large transportation volume. It is a large-scale mechanical equipment used to dump bulk materials of railway gondola. It is a loading and unloading machine that can turn or tilt the rail vehicle to unload.

The work flow of the car dumper can be roughly divided into three steps (as shown in Figures 1, 2 and 3):

In the first step, the train is pulled into the dumper through the automatic positioning traction system of the dumper;

The second step is to fix and lock the train carriage with the hydraulic fixing device integrated on the dumper;

The third step is to start and turn the car dumper, unload the goods in the car and return to the original position.

Detection purpose

The dumper can load three cars at the same time, and each car can load 100 tons of coal. In addition to the weight of the car itself, under the actual load, the dumper will carry nearly 400 tons. After the overturning and unloading, the weight on the dumper instantly decreases by more than 75%, the stress is obviously reduced, and the motion track of the dumper bearing will change compared with the actual load.

Since the train does not take off the hook during the whole process of unloading goods into the dumper, if the movement track of this bearing changes too much, the connecting bearing between carriages will be broken. Therefore, it is necessary to detect and compare the real load and no-load motion trajectories of the car dumper respectively, and adjust the gear mechanism located at the lower part of the car dumper to control the change value of real load and no-load within the theoretical range, so as to minimize the fracture probability of the connecting bearing between cars.
API solutions

Using the radian Laser Tracker and the active target (at active target), the motion trajectory of the dumper can be dynamically captured in real time, and the trajectory diagram can be obtained and compared and analyzed, so as to determine the direction and amplitude of adjusting the gear mechanism at the lower part of the dumper.
During measurement, first put the radian laser tracker in place, then fix the activetarget active target on the car connecting shaft on the side of the car to be overturned on the car dumper (see Figure 4), then connect the radian laser tracker with the activetarget active target and wait for the car dumper to start.

After the car dumper is started, with the operation of the car dumper (see Figure 6), the radian laser tracker will automatically and dynamically record the whole movement track and display the three-dimensional coordinate positions of all points on the software. Since the active target can actively capture the laser light of the tracker, it will never break the light during the whole measurement process, resulting in abnormal measurement results.

As shown in Figure 7, it is the running track of the dumper displayed in the software. The blue arc represents the running track of the dumper under real load, and the red represents the running track of the dumper under no load. After the motion trajectories of real load and no-load are obtained respectively, the theoretical values can be calculated and compared by software, so as to obtain the adjustment orientation and value of the lower gear mechanism of the dumper.

Update of detection methods

Before using the radian laser tracker, the detection of the car dumper is usually fixed at each position of the car to be overturned with several tension meters, and then the adjustment scheme of the gear mechanism is finally determined through the reading of the tension meter. However, the detection method using tension meter is inefficient, often has the problems of incorrect position or poor personnel cooperation, and the accuracy is difficult to get the best guarantee.

The measurement method of radian laser tracker + active target provides a more accurate, convenient, efficient and objective omni-directional dynamic measurement solution for the detection of car dumper.