The CSIR developed a method of rebuilding the tenons of turbine blades to address challenges in Eskom's maintenance programme.

Working closely with Eskom technicians, CSIR laser welding specialists identified possible welding materials and techniques to suit the rebuilding of tenons.

Generally, a large number of turbine blades are scrapped during turbine maintenance and repair projects. The in-situ rebuilding of the tenons on turbine rotors by laser metal deposition is a time and cost-efficient option of repairing the blades for continued use. This also means that only the blades that are affected by the maintenance activity need to be refurbished without the need to scrap or remove any blades from a rotor.

Another way the refurbishment reduces costs is by ensuring that a number of rows of scrapped blades that can return to service or be available as spare sets after complete refurbishment, remain available. This is not only a saving on parts replacement, but also avoiding downtime.