Steinmüller Africa, a pioneer in high-pressure steam generation equipment, along with engineering consultants, eNtsa, successfully used rotary friction welding to fabricate four headers used for high-pressure water heater boiler units installed on Tutuka power station in Mpumalanga.
The duo used a hybrid of rotary friction welding and friction hydro-pillar processing (FHPP) to attach 448 heat exchanger nozzles onto each of the four high-pressure headers used in the final fabrication of the high-pressure heat exchangers.
This process needed to be developed as an alternative to the submerged arc welding method which is already in use.
The initial welds using the submerged arc welding method found defects in the first four headers and although the submerged arc welding process was further refined to have no defects, these four headers still needed to be repaired. To repair these defects, the two companies used a hybrid application of FHPP and rotary friction welding to weld the nozzles to the headers.