Laser scanner use in predictive maintenance at mining

Mining machines are subject to considerable wear and tear. Predictive maintenance is therefore important to avoid unplanned machine downtime.

Mining is becoming increasingly important in the age of growing demand for ores and rare earths. It is estimated that an increase of 7,000% in the yield of copper ore alone will be required to achieve the goals of electromobility.

Problem: Machine failure

As machines in opencast mining are subject to heavy wear and tear, unplanned downtimes mean considerable costs due to long waiting times for spare parts procurement and repairs. Predictive maintenance can be used to minimize downtimes due to unplanned repairs. This involves constantly measuring the most important wearing parts and calculating the degree of wear. This data can be used to calculate and plan a maintenance date. Spare parts and maintenance personnel are then available in a coordinated process.

New solution: 3D laser scanners measure wear

EXEMPLE1: Conveyor belts

In large opencast mines, conveyor belts with a length of 10-20 km are sometimes used. These conveyor belts are made of vulcanized rubber with steel inserts. Some of the material being conveyed consists of pointed and sharp-edged stones that fall from a tower onto the conveyor belt at a certain height. Sometimes these stones cut through the conveyor belt, causing a crack. If this crack is not noticed and repaired, it can expand due to the forces acting on the belt and eventually cut the belt completely open. As the plant continues to run for a while, the rock then builds up into a mountain and the plant has to come to an unplanned standstill. This often means that the downstream processing operations also come to a standstill. Such an accident is associated with high costs.

Conveyor belt

Crack on conveyor belt

Point cloud defects on conveyor belt

SOLUTION: Inline monitoring of the conveyor belts with QuellTech line laser

3D laser line sensors from QuellTech are used for the non-contact detection of cracks. The sensors project a laser line perpendicular to the direction of movement of the conveyor belt onto the underside at the point where the rock falls onto the belt. If a stone cuts through the belt, this surface change is detected in 3D by the sensor and recorded. Depending on the size of the defect, an alarm is triggered and, if necessary, the system is shut down in a controlled manner and repaired immediately. At another point, the surface of the conveyor belt is measured for wear using QuellTech 3D laser line sensors. As the belt is running at this point without conveyed goods and has been cleaned, the belt thickness and gradual wear can be measured at individual points. As the fault location is also recorded, a repair can be carried out precisely at the points found as part of predictive maintenance. This allows the service life of a conveyor belt to be extended in a controlled manner. The use of highly robust conveyor belts, which are sometimes 10 times more expensive, can thus be avoided.

New solution: 3D laser scanners measure wear

Example 2: Stone crushing machines

During the ore mining process, larger or smaller boulders are produced. In order to be able to transport the rock or ore on conveyor belts and process it later, it must be crushed. There are various machines that crush rock. On the one hand, there are large drums, inside which steel balls crush the rock with the help of gravity by rotating the drum. High-pressure crushing machines are much more efficient. These use 2 large counter-rotating rollers with certain cleats or wave-shaped structures on their circumference that pull the rock into the narrow gap between the rollers. In the process, the rock crushes itself due to the pressure of the rock chunks. Nevertheless, the surface structures of these rollers wear down considerably. This wear can lead to the roller becoming unusable.

Wear points on a mining conveyor belt

Point cloud of roller surface

SOLUTION: Inline monitoring of roller surface with QuellTech line laser

The service life of a roller depends on factors such as the type of rock, operating time and other factors. Until now, the wear of the roller surface has been measured manually.

QuellTech 3D line lasers can now be used to continuously monitor the wear condition of the rollers. For this purpose, a laser line is projected onto the roller surface by the sensor. Using the triangulation method, the diffuse reflection of this laser line is converted into 3D information on an image acquisition chip. This generates a three-dimensional point cloud of the entire roller surface. This point cloud is compared with the point cloud of the new condition of the roller and enables a statement to be made on the wear condition and a calculation of the further prognosis until the roller is replaced.

Advantages of the QuellTech solution for mining

3D display provides an overview of the wear condition over the entire surface
Continuous checking of the wear condition allows for forward-looking planning.
Quality assurance through early alarm in the event of serious faults, an emergency system stop prevents serious damage
Precise localization of defects enables fast repairs, eliminating time-consuming searches
Higher productivity thanks to less unplanned downtime
Cost savings through predictive maintenance