CSR E-Loco won the contract to supply 359 of its electric locomotives, with the Canadian firm Bombardier supplying the remaining 240.

Some have been for trains manufactured in China, with most delivered in parts to South Africa and assembled locally by the engineering division of Transnet.

More than 100 of its Chinese technicians have moved there to help in the assembly, and it has orders until 2018.

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The future looks bright. Premier Li Keqiang visited Ethiopia, Nigeria, Angola and Kenya in early May to strengthen China's economic ties with the continent, and pledged to continue to invest in African infrastructure, particularly high-speed railways, expressways and regional airports, a priority for Chinese companies.

He also underlined the importance of bringing Chinese expertise, especially in research and development, to Africa, along with the export of other leading technologies, particularly from the telecommunications and power industries.

Liang Guoyong, an economic affairs officer at the investment and enterprise division of the United Nations Conference on Trade and Development, said China has "unique technology that can be exported to developing markets and the rest of the world", such as in high-speed rail.

"Combined with its capital advantage, this will optimize the country's overseas investment landscape, which is centered on energy and resources currently," he said.

She Yongjun described the competition for orders in South Africa as "very fierce" because its rivals are mainly well-known global brands.

"Our advantage centers on price, delivery time and quality, which makes us comparable with the best in Europe."

Transnet freight rail, the largest division of Transnet, was impressed by the fact that CSR E-Loco delivered its first locomotive just 12 months after signing the contract in October 2012, about six months shorter than the global delivery average of 18 months, he said.