Mining Equipment: Select, Buy & Maintain

Mining Equipment: Select, Buy & Maintain

Table of Contents

Mining Equipment Selection

Some basic parameters had to be defined at the time:

  1. Mechanical or diesel electric trucks.
  2. Number of shovels versus size versus number of pits in operation.
  3. Size (height and width) of shops and doors.
  4. Number of repair bays.
  5. Cranes capacity.
  6. Number of service equipments (graders, dozers, loaders).

The maintenance shop was designed to be a component change-out shop – not a rebuilt shop. We found-out later, that the same shop can quickly become a repair/overhaul building if equipments do not perform as expected and have to be modified.

Mining Equipment Purchase

That extensive study resulted in a proposal to buy one (1) make of shovel, truck, and drill with a possibility of a second make for diversification purposes, so we could hopefully start operations with the best equipments on the market. Money or capital availability at the time was very different from what it is today.

What we knew then (from our experience at Lac Jeannine in the early 60’s) and what we have found out in the following years is that the fragility of some mining equipment designs renders an exhaustive study not a very reliable one, especially if it is a first design. We must rely on data given by the manufacturer, but these same data are based on theoretical criteria and have not been proven in the field or on the test ground; at least not sufficiently.

That is precisely what we have found out during the first years of operations. We had a large number of modifications to make on our trucks from the frame up on all three (3) makes of trucks, and on our three (3) makes of shovels. I am saying three (3) makes of equipment even if our study proposed one (1) make and a maximum of two (2), because there is an other factor (unknown maybe at the time of the study) which had a role in our decision: the market for large mining equipments.

Mining Equipment Operation & Maintenance

This push for bigger, more productive equipments resulted in a need for improved maintenance technologies and activities. The goal was and still is to keep these machines working as steadily as possible, giving good and constant availability, at the lowest cost/hour, with as few breakdowns as possible. This is not easily attainable in an open pit in Northern Quebec with temperatures of minus 40 to 45 degrees Celsius in winter, rain in the summer months which makes a mess of roads and benches from heavy traffic, and not forgetting the hard transition from winter to summer because of spring thaw.

The fleet of equipment we are currently operating today are:

mining equipment list

The number of hours we operate the equipments per year (1992) is as shown. This assumes these equipments are available and for this, a good maintenance program is a must.

mining-equipment-maintenance-program

Vibration Analysis

To monitor rotating equipment components, vibration is the most effective method of all the predictive maintenance techniques. With the ease and speed of collecting, storing and analysing data brought about by the use of microprocessors, predictive maintenance by vibration analysis is a tool which is an indispensable part of a maintenance department’s overall program. Predicting equipment failures has become a whole lot easier using computer programs to warn ahead of time of possible defects so corrective actions can be implemented before breakdown occurs.

Oil Analysis

While vibration analysis started in the early 80’s, oil analysis were functional in the first days of Mount-Wright. Actually, we used that technique in our former mine of Lac Jeannine, since the early 60’s.

That technique enables us to monitor the engines, gear cases, transmissions, etc. oil condition on an ongoing basis. The analysis give us indications on the wear of some parts, their condition, if that wear is acceptable or if some actions (parts change) have to be taken. In the case of a diesel or gas engine, the contamination by the cooling agent is a very critical situation, as is the presence of metal parts in the oil. The oil analysis, at regular intervals, is another indispensable tool to keep engines running and a very helpful tool to prevent premature changes of gears, shafts, bearings in a gear box.

Overhauls are performed on equipment after a given number of hours of operation which are different for shovels, drills, trucks, and loaders, and also vary from year to year. New equipment designs should allow us to spread these overhauls more; the cost of overhauls is one factor incorporated in the equation used to justify replacement of equipments after a specific number of hours of operations.

Replacement

Some parameters to help decide size and type are:

a) Ratio of trucks to shovels.
b) Capacity/productivity of equipment.
c) Technological updates.
d) Adaptation to cold climate.
e) After sale service.
f) Availability of repair parts.
g) Maintenance manpower available (at QCM).
h) Space available in our shops.
i) Roads/dumps/benches capacity.
j) Other

But before we can proceed with the acquisition of new equipments, we have to justify their replacement. The methodology used by Quebec Cartier to evaluate the economics for the replacement of equipments is based on historical information of the said equipments, which is divided in block of hours, smoothed and worked on with linear regression. Comparison of projected trends of cost between the unit to be replaced and the new model gives the gross savings resulting from the replacement of the unit.

As renewals came up, and/or new equipment as being acquired, it became apparent that Quebec Cartier was building up a substantial amount of leased equipment and as such, had build up an important amount of leverage vis-a-vis a potential direct financing source. This lead to direct negotiations with the financial institutions and more favorable financing rates. Additionally, by keeping the supplier as the guarantor of residuals, operating leases continued to be possible.

Looking Ahead

In the coming years we need to find a way for our people, at every level of the organization to participate more in the improvement of our operations. With the increasing competition over the different types of concentrates (and pellets) on the world market, cost of operation and quality of product will be paramount in keeping our market share.

selection purchase and maintenance of mining equipment