Any unplanned downtime in a truck-and-shovel mining operation arises from a combination of technical faults, poor maintenance, human errors, and logistics constraints at the site. Some of the key methods of reducing this include preventative maintenance, improving operator skills, quick problem recognition, and improved coordination of the fleet.
In a truck-and-shovel mining fleet, the major reason behind unplanned downtime will be mechanical failures: engine, hydraulic, tire, GET, hoist, pin, pump, and even electrical failures can arise without warning, causing immediate problems for a single truck or shovel. In addition, mining-specific literature also mentions that while wear and tear may go unnoticed, the approach of merely addressing problems as they occur without dealing with their root causes leads to defects in components turning into malfunctions.
Another common cause of excessive downtime is inefficient maintenance planning or neglecting preventive maintenance altogether. In cases when service, inspection, lubrication, and replacement are postponed, minor issues turn into failures which are costly and time-consuming to address. The traditional approach to addressing this problem is the development of an efficient preventive and predictive maintenance strategy along with proper shut-down periods and sufficient spare parts inventory.
Operator-related errors often lead to equipment malfunctions and downtime. Issues such as improper loading, rough operation, inadequate gear use, improper pre-operation checks, and neglecting noises and overheating of machinery are typical of many equipment downtime incidents. In order to prevent this from happening, the company should focus on improving operators’ competence through adequate training programs and encouraging the early detection of faults.
Coordination difficulties between the shovels and haul trucks are another possible cause of downtime despite no machine problems. When trucks are too late, wrongly scheduled, or missing, the shovel sits idle. Likewise, poor shovel performance or downtime causes truck queues and a loss of productivity. These can be avoided by mines through effective dispatching, fleet balancing, matching shovel-truck capacities, good traffic management, and monitoring of queues and availability.
Furthermore, other external issues related to infrastructure may also contribute to downtime in certain conditions, such as electric machines or those in difficult mining conditions. For instance, electricity outages, damaged cables, poor road surfaces, oversized loads, flooding, adverse weather conditions, among others, may hinder loading and hauling or cause mandatory safety downtime. The usual strategies include frequent road repairs, proper drainage, weather considerations, appropriate blasting and fragmentation, electric shovels’ cable management, and rapid response teams.
In reality, all these strategies should be combined into a single reliability strategy. Namely, it should involve preventive maintenance, predictive diagnostics, operator discipline, spare parts availability, and fleet coordination. Reliable and accurate mining and fleet information shows that such an approach significantly minimizes unplanned downtimes and accelerates repair operations.
