Management of Mining Machinery

Mining for resources from the earth has increased steadily over the past few decades and at present is a multi-billion dollar industry. The machines used in mining operations are usually very big and expensive. Therefore in order to make a mine productive and profitable, the machines have to be managed in an effective and efficient manner.

To do this it is a mine managers duty to make sure that,
- The machines give continuous service (availability of machines)
- The machines do not fail frequently (reliability of machines )
- optimize the machines so that they operate at maximum efficiency

In order to satisfy these criteria, machines of good quality have to be obtained. When acquiring machines for a mine, several things need to be given consideration. First, the cost of the machine should be considered. Naturally machines with a lower price are likely to be of poor quality and will fail often, while machines with a higher price generally are (but not always) of high quality. Therefore in this situation the purchase price alone is not taken into account. Instead the "life cycle cost" is calculated. The life cycle cost includes the purchase price, cost of maintenance as well as the cost of disposal of the machine. This gives a good measure of the usefulness of the machine during the operation period of the mine.

Next the performance of the machines must be considered. To assess the performance of the machines, key performance parameters such as Availability, Utilization and Efficiency and Reliability are defined as given below.
- Availability = available hrs/scheduled hrs
- Utilization = utilized hrs/available hrs
- Efficiency =  productive hrs/utilized hrs
- Reliability is the probability of operating without failure.
Failure of mining machinery is a somewhat common occurrence and leads to significant losses. This is a fact that needs attention because if maintained properly, failure can be almost avoided completely. This is not impossible because aircraft and ships are maintained so well that a failure of an aircraft or ship is a rarity these days. Therefore with proper maintenance, mining machines can also reach a situation like this.

Maintenance of machines needs to be carried out with a proper maintenance strategy plan. Several approaches can be taken in this regard. They are
- Preventive maintenance  - maintenance with a schedule based on time
- Predictive maintenance  - maintenance based on current condition and future predictions drawn from it
- Proactive maintenance  - maintenance based on the root cause of possible problems
- Reactive maintenance  - continue to run until component fails and then replacing.
Maintenance costs includes the cost of spare parts as well as the losses due to any delay in aquiring the spare parts. Therefore the availability of spares also needs to be considered.

Managing mining machinery is a continuous and cyclic process and if done in the proper manner, it can improve the operating efficiency of the mine and make the mine a more profitable venture.

image from : wikipedia