Specialised welding and mechanical maintenance company Hydra Arc is currently conducting highly specialised plant maintenance on a coal-fired power plant in Secunda, in Mpumalanga. 

The welding and mechanical part of the maintenance includes work on a variety of equipment, such as high pressure water tube boilers which operate by means of heated water circulating in the tubes. 

Hydra Arc’s maintenance of the small diameter 2¼" chromoloy (CrMo) tubes and mud and steam drum allows the boiler to tolerate much higher steam pressures for power generation. The maintenance of the air heaters is essential to increasing the efficiency of the boiler by reducing the amount of useful heat lost in the flue gas. 

Hydra Arc’s maintenance of the fly ash hoppers on electrostatic precipitators as a result of flue gas condensate is crucial to ensure boiler efficiency, while structural repairs on the ‘precip hoppers’ is essential for the structural integrity and durability of this equipment. 

Welding repairs on the wet deasher of the boiler, in which ash is discharged into the ash canals beneath the boilers, is imperative for structural reliability and wear resistance.  Hydra Arc uses a range of welding materials throughout the turnaround periods, including  2¼" CrMo piping, carbon steel, structural steel and stainless steel, with welding conducted on equipment such as boiler tubes, pressure retaining tanks, structures, vessels and pressure piping. 

Hydra Arc is compliant with all relevant codes and standards for design, fabrication, non-destructive evaluations and welding, including American Society of Mechanical Engineering codes and standards, European standards and American welding society standards.

The Hydra Arc team comprises over 400 employees with skills ranging from project managing, welding, boiler making, pipefitting, mechanical, material controls and quality controls.  Hydra Arc complies with  all ISO 45001 and 9001 requirements and its operational organisation is supported by a highly experienced safety team.