HomeEnergy MineralsGoedgevonden to reach full production in 2010

Goedgevonden to reach full production in 2010

The Xstrata Coal operated Goedgevonden mine is building up to a targeted annual production of 13 million tonnes of coal, and this opencast operation has bought a new predominantly Caterpillar fleet to achieve this. The 37 unit Caterpillar fleet includes the first 993K Cat wheel loader to reach South Africa.

Goed1

The first 993K Cat wheel loader to
reach South Africa loads a Cat 785
haul truck at Goedgevonden.

Goedgevonden, which is 51% owned by ARM Coal (itself owned 51% by African Rainbow Minerals and 49% by Xstrata) and 49% directly owned by operator Xstrata, represents a transition for Xstrata in South Africa from mostly underground to opencast coal production. Xstrata is the country’s third largest coal exporter, and Goedgevonden, located seven kilometres from Ogies near the now renamed town of Witbank (Emalahleni), will be mainly an export colliery.

Acting operations manager at Goedgevonden, Gert Potgieter, told Mining Review Africa earlier this year that the mine is looking to deliver six million tonnes of coal in 2009 before reaching some 11 million tonnes in 2010, and from then onward maintaining output at 13 million. More than 70% of the coal produced will be transported to the Richards Bay Coal Terminal (RBCT) for export. In full production, some three million tonnes a year of low grade high ash coal will be supplied to Eskom, whose Kendal power station is within sight of the mine. Goedgevonden has an estimated 30 to 35 year life-ofmine.

Xstrata acquired Goedgevonden when it bought Duiker Mining in 2002. It re-evaluated the reserves and started a trial open pit mine in May 2003, and was producing some 1.2 million tonnes a year with mining undertaken by contractors and the coal taken elsewhere for washing.

However, with a large expansion, the operation has converted to owner mining. This saw the purchase of the Caterpillar fleet and the establishment of a maintenance and repair contract with Barloworld that sees a 28 strong Barloworld team on site to maintain the equipment, including seven diesel mechanics. The mine is also building a 1.2 million tonne a month washing plant, with Murray & Roberts Cementation and Sandvik Mineral Handling as the main contractors. That facility is planned to become operational during the second quarter of 2009.

Gert Potgieter

Acting operations manager at
Goedgevonden, Gert Potgieter.

The mine, which has a stripping ratio of 2.5:1, has eight to 10 metres of free dig overburden, and then mines No 4 Seam coal, which is four to five metres thick. This is followed by an intermediate hard rock zone of some 13 to 18 metres, which is removed before the No 2 Seam of some four to six metres thickness is mined. From an operational viewpoint, one of the biggest headaches during the production ramp-up is the clayish nature of the overburden. At the end of January 2009 the operation installed an exhaust system in two trucks to blow hot air to reduce the carry back of material, which can be 30% to 50% due to its clayish nature. The interburden requires blasting and BME is the explosives contractor.

The mining fleet, which is owned and operated by Xstrata, arrived on site in mid-2008, and in late January 2009 was in service, with some operator retraining underway at the same time, as many of the 120 Xstrata personnel were underground miners previously.

Potgieter says that Barloworld won the contract to supply the majority of the fleet, which was won on open tender, because of its good relationship with the group and its ability to work with it in providing maintenance and spares. Of the 42 strong Goedgevonden fleet 37 are Cat machines.

One of Potgieter’s priorities is showing people how to increase productivity in terms of cycle times and volumes achieved per day and per month, and this extends to looking at haulage roads. The mine has obtained a crushing plant and is using it to produce aggregate for preparing roads, and it is also working with Dust-A-Side. The maximum haulage distance to the plant’s ROM pad is some 3.7 to 4.0 km, giving the mine an 8.0 km haulage cycle.

The maintenance and repair contract with Barloworld, which includes guaranteeing equipment availabilities, is complex with different availabilities guaranteed for different stages of the equipment life and for different pieces of equipment. However, looking at broad averages unrelated to specific details, Potgieter says the mine, as it builds up, was earlier in the year achieving an equipment utilisation of some 70%, and the aim was to get this up to 80% ultimately.

Johan Maritz

Barloworld’s Goedgevonden project
manager, Johan Maritz.

The mine has three Hitachi excavators, an area where Caterpillar does not compete, and South Africa’s first 993K wheel loader as production machines. However, the 993K, though it has a large coal bucket capacity of 23.7 m3, is not intended to compete with dedicated excavators, which feature bucket sizes of 15 m3 at Goedgevonden. The 993K brings its own strengths and in January 2009, the month it went into production, it was surpassing expectations, according to Potgieter.

By the end of January it had already spent some 370 hours in operation, and both Potgieter and Barloworld’s Goedgevonden project manager, Johan Maritz, point out that the machine offers the mine a great deal of flexibility.

Unlike the excavators, which are quite stationary machines, the wheel loader offers mobility. As it can move from point to point easily and rapidly, it can be used for cleanup and for working on stockpiles. The machine’s positive flow control hydraulic system ensures 10% to 15% faster cycle time, and the breakout force of 709 kN and high fill factor contribute towards its high productivity.

Maritz says the machine is intended to operate for some 250 hours a month, though once in operation mines tend to like the 993K and it operates for more hours. It will probably do some 500 hours a month at Goedgevonden. This translates into a machine life of some 10 years, as it has a 60,000 hour structural life before any major refurbishment or replacement is required. The 993K undergoes major services every 6,000 hours as well as daily and routine services. This life of plant and service schedule is the same for most of the fleet, and the maintenance and repair contract, which ensures the equipment is not run to destruction, will give the mine a good option in terms of refurbishment versus replacement when the time comes.

The 993K fills a gap between the 994 and 992 offered by Caterpillar. The 992 is ideal for loading 90 tonne capacity 777s, while the 994 is ideal for loading 789s which have a 190 tonne nominal payload capacity. The 993K can load a 777 in four passes and a 150 tonne capacity 785 in six passes.

Goed2

One of the two Cat 777F water bowsers
at Goedgevonden, each of which
has an 85,000 litre capacity

The Caterpillar fleet at Goedgevonden, which is worth some R450 million, includes three 16 M motor graders, three D10T and four D11T track type tractors. Two of the D11T dozers are fitted with coal blades for transport related coal handing while the rest of the D10T and D11T’s are equipped for mining. There is a 785 flatbed vehicle for transporting the less mobile equipment, and five 789Cs which are used for overburden and interburden haulage. The mine’s fleet of nine 785s are split, with three being hard body trucks for overburden and six used for coal haulage. The fleet also includes two 777F water bowsers each with an 85,000 litre capacity, one 834H tyre dozer, one 988 front end wheel loader, and a 980 tyre handler. There are two 740 service trucks one of which is used as a diesel bowser. The fleet also includes two DM30 drill rigs for the coal and two Pit Vipers 275’s for the interburden drilling. The drilling units are Atlas Copco machines; Barloworld has had a distribution agreement with Atlas Copco.

Earlier in 2009 the Barloworld maintenance team moved into a dedicated four bay workshop on the mine site. This workshop has an overhead crane and buffer fuel points. Maintenance is predictive and based on scheduled operating hours. Parts are obtained from Cat stock kept at Barloworld’s Middleburg depot and regional facility 70 kilometres away. That facility serves the coal mines in Mpumalanga.

Xstrata has its own operator training centre, where it tests people to see if they have the required hand eye coordination to be good operators, before they undertake buddy training on an actual machine. Barloworld has also undertaken operator training at its Isando facility. A focus at Goedgevonden with regards to the fleet has been on optimising operator and mine safety and ergonomics, machine stability, good visibility, improved egress and access for ease of maintenance. The Caterpillar fleet meets all of these requirements. The use of a predictive maintenance system entails sampling and analysis of oil to track and predict wear related problems and prevent these before they happen.

LATEST FEATURES