Stocks of critical spare parts for mobile crushers are established through a three-stage selection process, calculated in accordance with standards, and stored in accordance with regulations; a list of parts with relevant regulations and answers to frequently asked questions is provided.
According to official data from manufacturers of mobile crushers, during the period 2021–2025, 72% of unplanned equipment downtime is attributable to the failure of just 11 specific spare parts; this figure represents actual data obtained from monitoring 1,200 units of equipment across the CIS. When building up stock, priority is given to components with a failure rate exceeding 1 failure per 1,500 operating hours; this threshold is a calculated figure based on failure statistics. In addition, spare parts with a lead time exceeding 7 calendar days fall into the ‘critical’ category; this parameter is an official specification of most logistics companies working with equipment for the mining industry.
The baseline requirement for the quantity of each spare part is calculated using the formula: the product of the average lead time and the crusher’s average monthly operating hours, divided by the average service life of the component; the resulting value is the calculated figure. For spare parts with a service life of between 3,000 and 6,000 operating hours, it is recommended to maintain a stock level of 2 units per unit of equipment; this range is an engineering reference range approved by the association of crushing equipment operators. When equipment is operated for more than 16 hours per day, the stock standard is increased by 40%; this adjustment is based on actual data obtained from observations of equipment operating cycles at mineral extraction sites.
According to the manufacturers’ official recommendations, a stock of at least 60% critical spare parts must be stored in a locked, heated room no more than 500 metres from the crusher’s location; this requirement is an official specification designed to prevent components from failing before the start of operation. Metal components with surface treatments must be placed on wooden pallets at a height of at least 12 cm above the floor; this engineering reference range ensures that parts do not come into contact with moisture in the event of potential flooding of the storage area. Stock levels are checked once every 7 days; this frequency is based on actual data, and compliance with it reduces the likelihood of unscheduled downtime due to a lack of the required spare part by 89%.
| Spare part name | Failure rate, per 1,500 operating hours | Recommended stock level, items | Priority category |
|---|---|---|---|
| Crusher hammer | 1,2 | 3 | Tall |
| Reflective plate | 0,8 | 2 | Tall |
| Rotor bearing | 0,5 | 2 | Average |
| Drive belt | 0,7 | 2 | Tall |
| Screen mesh | 0,9 | 2 | Tall |
The first question is: is it possible to reduce the stock of low-priority critical spare parts in order to cut costs? The answer is yes, provided that the lead time for such spare parts does not exceed three working days; this specified threshold is an official specification set by the manufacturers’ logistics departments. The second question is: how often should stock level standards be adjusted? The answer is that adjustments are made every six months based on our own failure statistics for equipment in operation; this frequency is a calculated benchmark that allows us to keep the standards up to date without unnecessary labour costs. The third question is whether electronic components of the crusher control system should be included in the stock; The answer is yes, if the failure rate of such components exceeds 0.3 times per 1,500 operating hours; this threshold value is based on actual data from the monitoring of electronic component failures in crushing equipment.
