Cracow Gold Mine

MinLog delivers measurable results at Evolution Gold’s Cracow Gold Mine

COMMODITY: Gold
OPERATION: Cracow Gold Mine, central Queensland, Australia
TYPE OF ENVIRONMENT: Underground-open mining
SOLUTIONS DEPLOYED: MineSuite FMS with Payload Optimisation and Proximity Awareness module using RFID tags

Background

Cracow Gold Mine is located in central Queensland, Australia northwest of Brisbane. At the time of implementation it was held by a joint venture between Newcrest Operations Limited and Lion Selection. Gold production began in 2004, with a life-of-mine of 10 years, which has since been extended by initiatives such as the Roses pride extension and which may be further enhanced by the discovery of mineralised vein structures.

Ore from Cracow’s four mining areas is hauled to the surface ROM stockpile. Cracow operated a fleet of 50 vehicles at the time of the implementation, and employed 85 employees underground.

Requirement

At the time Cracow expressed a need to improve haul fleet productivity by optimizing haul cycle payloads and minimizing variation. This would also have a positive effect on maintenance in that the fleet would be operating within design parameters, as well as on safety because of a reduction in spillage. Cracow believed that with sufficient accurate and in-time information related to loader source location, material type, payload and historic performance information, productivity could be improved, setting a target of 49 tonnes for the average payload as well as a decrease in variation.

A subsequent and associated requirement related to safety. Consistent with most underground mining operations, their safety challenges related for the most to proximity awareness as far as their Heavy Vehicles were concerned.

Solution

Both the aforementioned could be accomplished and was effected by the progressive implementation of MineSuite Fleet Management solutions, providing for an automated reporting system and also as a proximity awareness aid for heavy vehicle operators.

The MineSuite Fleet Management System was fitted to production loaders and trucks to provide in-cabin information to operators. The system was originally deployed to include seven trucks and loaders fitted with MineSuite Field Computer Equipment inclusive of proximity detection equipment. RFID technology was used to identify their location and other equipment underground. More than 100 locations were tagged, along with every piece of mobile equipment.

The system was configured to communicate with the server by means of periodic wireless uploads via hotspots in the underground fuelbay and surface weighbridge. Time and motion, delay status and productivity of the fitted machines are all recorded, as well as information entered by the operator.

The in-cab display in certain heavy equipment not only provides production information to the operator, but also activates a visual and audible alarm if any heavy or light vehicles come within proximity range, providing for Operators’ acknowledgement and multiple detections by name which is cleared once the vehicle moves out of range.

Challenges

The challenge posed at Cracow was that of improved productivity through increasing the average payload hauled to surface. There was also a need to limit the communications infrastructure requirement as far as possible, whilst providing for a real-time, integrated proximity awareness solution.

Outcomes

Payload distribution and variation were measured over three consecutive quarters with data was collected following the commissioning of the system. Average and standard deviation were the two most relevant measures of optimised payloads. This data was analysed to compare operators (or at least crews – made up consistently of the same two or three loader operators), as well as to examine from an operational perspective site-wide trends over the nine-month period. Significant quarter on quarter gains on the two measures of optimisation were revealed, over the site as a whole and when broken down by individual crew. This showed a consistent and sustained shift in the mean payloads as well as a significant decrease in the variance of payload tonnages.

The MineSuite FMS Proximity Awareness module, in turn, also yielded measurable results. Designed with operators in mind, the in-cab MineSuite FMS tablet features a visual and audible alarm which is activated if any heavy or light vehicles come within proximity range. Following implementation, Cracow conducted a survey of equipment operators whom indicated that collisions are most likely to occur:

  • Backed over in a stockpile
  • Leaving a level and entering the decline
  • Driving into the sun
  • Coming around a corner

The survey also showed a general acceptance of the MineSuite system with a positive perception of MineSuite as a worthwhile addition to safety controls, since:

  • 50% of the time vehicles detected were out of sight
  • 40 m was the average detection distance

In summary the original justification for implementing the Fleet Management System was to improve the average haul from 45 to 47 tonnes per trip. A study over three quarters verified this with the site now achieving more than 48 tonnes per trip. The system provided the data and information that enabled optimisation of payload tonnages of the underground fleet. A 2.5 tonne increase in payload per trip represents a 5.4% improvement in productivity. Cracow has also since implementation concluded that proximity awareness is effective as one aspect of the safety matrix for underground hard rock mines.