DCD-Dorbyl Heavy Engineering has been commissioned by various divisions of Outotec – a leading global provider of process solutions, technologies and services for the mining and metallurgical industries – to produce no fewer than 19 ball and SAG mill shells for customers in three African and six overseas countries. This is a set of orders which will take the company well into 2008, according to marketing manager Bennie Bosch.

This Dorbyl division – one of the largest facilities of its kind in the world – has received three orders from Outotec South Africa. It is manufacturing a 5.5 by 8.5 m ball mill shell for the R2.6 billion Nkomati nickel project in the Machadadorp area of Mpumulanga, as well as two 6.1 by 8.7 m ball mill shells for the Elandsfontein platinum project. The third order is for a 3.1 by 5 m ball mill shell for the US$145 million (more than R1 billion) Perkoa zinc project in Burkina Faso.


DCD-Dorbyl’s Boksburg facility,
where the new iron ore locomotives
will manufactured

Meanwhile Outotec Australia has commissioned DCDDorbyl Heavy Engineering to manufacture a 1 by 9 m ball mill shell for Frontier Copper in the Democratic Republic of Congo (DRC), and a 24 foot by 14 foot SAG mill shell for Didipio gold mine in the Philippines.

The company is also working on a 24 foot by 14 foot SAG mill shell and an 18 foot by 27.5 foot ball mill shell for the Sabodala gold mine in Senegal. For Chatree gold mine in Thailand, it is manufacturing a 24 foot by 14 foot SAG mill shell and a 19 foot by 32.5 foot ball mill shell. A 22 foot by 12 foot SAG mill shell has been ordered for Sulphur Springs copper mine in Australia, together with an 18 foot by 28 foot ball mill shell.

Outotec USA has commissioned DCD-Dorbyl Heavy Engineering to produce two 4.6 by 11 m ball mill shells for the Atacama iron ore mine in Chile, as well as an 18 foot by 30 foot SAG mill shell for Kittila gold mine in Finland.

Finally, on order from Outotec Sweden, the company will be manufacturing two 6.5m pebble mill shells for LKAB Iron Ore of Sweden, as well as two 6.5 by 6 m autogenous mill shells.

With up to 75% of its business derived from exports, DCD-Dorbyl Heavy Engineering is enjoying a growing reputation as far afield as Europe, Australia, Sweden, Canada, the United States, South America, and even Mongolia.

In another significant development, DCD-Dorbyl’s Rolling Stock Division (RSD) has been awarded a contract to supply 64 three-axle bogies for the new Class 15 E locomotives destined for the Orex ore line in South Africa.

Orex is a specialist business unit of Spoornet, dealing with the transportation of iron ore over the 861 km railway line from Sishen to Saldanha Bay. Following the high demand for exports of iron ore, improvements to the line have been implemented since 1988.

The investment in new iron ore locomotives forms part of Spoornet’s strategy to increase annual capacity to 41 million tons by October 2008, with 35 million tons allocated to Kumba Resources and six-million tons to Assmang.

“RSD has a well-established reputation in this field, having supplied virtually all the electric locomotive bogies for South Africa’s national railway, including coaching stock and self-steering freight wagon bogies,” says business manager Norman Taylor.


A rotating mill at LKAB Iron Ore in Sweden.
DCDDorbyl Heavy Engineering will
be supplying Outotec Sweden with two
6.5m pebble mill shells for LKAB

The bogies have been designed specifically for the heavy-haul Co-Co locomotives. They incorporate features and service-proven principles from past experience. The design incorporates the CSC/GSI traction link system to ensure minimal load transfer between axles. It also optimises the adhesiondemand characteristics.

The bogie design includes GG journal bearings incorporated into a single-link axle-box design to ensure long life and minimal maintenance. Another feature is the pendulumtype traction motor nose suspension, which minimises lateral constraint for better curving characteristics.

The short wheelbase, hydraulic dampers and solid rolled steel wheels all contribute to a reliable bogie configuration with optimum performance and low life-cycle costs. Dynamic performance simulation, finite element analysis, three-dimensional CAD technology and standardisation were applied in the design process to ensure optimum results.

The 32 new Class 15 E electric locomotives will be the most powerful locomotives in Spoornet’s fleet. This investment follows a R3.5 billion deal for 110 locomotives, announced in February 2007, for the coal line to Richards Bay. Delivery is scheduled to commence in 2008.

The iron ore locomotives will be supplied by Venus Railway Solution, and the main sub-contractor is The UCW Partnership. The new iron ore locomotives will supplement the existing 31 Class 9 Es. Delivery of the bogies is set to begin in the second quarter of 2008, with the final bogies to be delivered by mid-2009.