NMMU saves Eskom R1 billion

In recognition of their work on the Hendrina Turbine project – saving Eskom R1 billion – Nelson Mandela Metropolitan University professor in mechanical engineering and technology manager Danie Hattingh and his engineering team (eNtsa) won the 2012 Eskom Chairman’s award for Innovation, together with their research partners from Eskom.

The combined eNtsa/Eskom team implemented NMMU-developed WeldCore® technology, a unique sampling and repair technique, for the Hendrina turbine rotors. Engineers within the eNtsa group in collaboration with Eskom’s Resources and Strategy Division developed WeldCore® technology.

This process involves specialised equipment which enables a coring tool to remove a sample from a thick-walled structure. The sample is then analysed to determine the life expectancy of the structure (material). The removed sample area is then repaired by the same machine, using friction hydro pillar processing. For this project, a purpose-built platform was developed to implement the WeldCore® procedure on the Hendrina High Pressure (HP) turbine which led to significant time and cost savings.

Due to this project, the power generating unit was returned to service without delaying or reducing output. This technology will now be further developed and refined for various other applications within power stations locally and internationally.

This technique saved Eskom an estimated R1 billion by avoiding the early replacement of HP rotors at Hendrina. The innovation directly supports Eskom’s strategic imperatives of keeping the lights on and becoming financially sustainable.