Alternatives to fastening bolts to prevent halts in the crusher
Premio: 18,000 $
Codelco Tech is Codelco’s subsidiary focused on technological development. Codelco is the main Chilean company and first world copper producer. Its goal is to become the new innovation world-leader within the mining industry by moving towards a model based on the development of open solutions.
Aware of the ever-growing needs of the mining sector, Codelco boosts the best available capacities to achieve technological improvements that allow a leap towards a safer, more environmentally-friendly, and sustainable mining.
Once an ore body has been identified deep down, the extraction must be made underground, so it is necessary to develop a series of tunnels and big-sized excavations through which the field is developed.
Depending on the quality of the rock, these excavations require different kinds of reinforcements to stabilize them and keep the operations safe. The reinforcements used today to stabilize the excavations are elements (bolts) that combine cement and steel.
You can watch the installation of the bolts in this link:
Once the material has been extracted, it is reduced in crushers to be able to carry it up to the surface. The problem is that when this material has some of the bolts used to reinforce the rock mass because this causes unplanned halts and damage in the crushers, which translates into a higher operation cost, approximately 4.1 USD millions in two years and in one crusher. There have been unsuccessful attempts to detect and eliminate the bolts before the crusher.
This video shows how a crusher works:
Characteristics of the bolts:
• Metallic bolts SAFEROCK of Ø 22mm and 50-200 mm of anchor length.
• Tensile strength of the bolts: 440 MPa.
• Yield strength 280MPa
• Density 7.87 g/cm3.
• Elongation 16%.
• One subterranean mine needs approximately 100,000 bolts with a 9.5 USD unitary cost. Therefore, the global cost in bolts is close to 1 million USD/year.
Click on the link for more information about the bolts:
See attached file with pictures of the bolts.
What the client is looking for:
This challenge is focused on replacing these iron elements for elements that are crushable in a crusher without causing damage. Moreover, they must not lose the mechanical capacity of support that the current iron elements have.
Additionally, it would be desirable that these new reinforcement elements could be produced in situ, at the same galleries where they are installed.
The proposed alternatives must still comply with the mechanical characteristics of the currently used bolts, and their installation must comply with the safety norms inside the mine, concerning gas generation and flammability of reagents.
Even if the initial preferred solution is to replace the current iron bolts by a crushable bolt, other approaches related to the crushing process could be considered, always to avoid damages in the crusher. In this case, additional challenge information will be provided in round 2, but not before.
The proposed solutions will be assessed according to the following criteria:
• Compliance with mechanical characteristics.
• Reduction of faults in the crusher.
• Business case.
• An easy in situ production of the bolts will be highly valued.
This is a 3-round competition with the following submissions:
A PDF document including:
• Brief description of the proposed alternative, including a high level specification (sketches, mechanical characteristics, materials…).
• High level business case
• Detailed specification (drawings, materials…).
• Detailed business case
• Installation process, including required equipment.
If required, additional information will be provided during the course of this round.
• Proposal for development and implementation of the solution.
This is a 3 round tournament:
1st round – 6 weeks + 2 weeks for evaluation.
2nd round – 4 weeks + 2 weeks for evaluation.
3rd round – 2 weeks + 1 week for evaluation.