Rope access use can assist in speeding up maintenance and shortening the duration of shutdowns and planned outages at State-owned electricity entity Eskom’s coal-fired power stations, states industrial rope access specialist Skyriders Access Specialists marketing manager Mike Zinn.
“Rope access can further add value to these maintenance shutdowns in terms of cost savings by creating fast and safe access to the maintenance areas, with specialist teams performing the required tasks,” Zinn emphasises, highlighting the current national electricity grid constraints and the power utility’s funding constraints.
“Power stations can save in excess of 25% in costs by using rope access, depending on the task,” he states.
Skyriders has provided Eskom with rope access services for more than 15 years. Zinn notes that, although scaffolding has been used in the past, rope access has proved a more efficient means of gaining access to high-elevation structures, particularly in the power generation sector. “Rope access is significantly faster and cheaper, as well as more flexible.”
Zinn says that a number of inspections and a fair amount of maintenance at some of the utility’s 13 power stations, including Kendal, Tutuka, Majuba Matimba, Komati and Kriel, are performed using ropes, reducing the need for expensive and time-consuming traditional access systems.
However, Zinn estimates that, of the inspections and maintenance that could be performed using rope access as opposed to the more traditional access systems, only 15% to 20% are currently performed using this technique. Zinn attributes this to the diverse maintenance philosophies and methods applied at the various power stations across the country.
Meanwhile, Skyriders completed maintenance work and the installation of a new air-cooled condenser fan guard at the Majuba power station, in Mpumalanga, in February.
“Traditionally, this is quite a difficult area, owing to the heights at which the fan guards are [located], and the difficulty in working with cranes,” Zinn notes.
Other completed maintenance contracts include work for the Matimba power station, in Lephalale, Limpopo, in January, which required working at a height of 90 m. “Skyriders was responsible for a magnetic particle inspection and minor welding repairs on the flue gas ducting,” he says.
The most recent project included the required maintenance work on two of the station’s stacks. “This involved a high-pressure wash of the two stacks and the application of acid resistant paint to the top 40 m of the 250-m-high stacks,” Zinn explains.
The company also completed work at the Medupi power station, in Limpopo, and the Tutuka power station, in Mpumalanga, using rope access. Work at Tutuka in 2014 required industrial vacuum cleaning work on hard-to-reach structures that were inaccessible using the more traditional access systems.
Meanwhile, Skyriders was tasked with carrying out concrete repairs (snag listing) on the Medupi power station’s water treatment plant, which is responsible for processing all the processed water from the power station, including runoff water and the process water from the plant. The work was completed in October/November 2014.
Skyriders has also had a permanent rope access maintenance and inspection team at Kendal for the past ten years, assisting with various tasks, such as boiler internal inspections, inspections of the PF pipes, coal bunkers, terrace bins, precip hoppers and ducting. “Teams have also carried out maintenance on the roof and side sheeting, the bucket elevators and smoke stacks,” Zinn says.
While services provided for the power stations by Skyriders include inspection, concrete inspection, nondestructive testing, maintenance and repairs, application of coating systems, work-at-height safety systems, welding and confined space rescue and standby, Zinn notes that a significant scope of work involves critical clinker formation inspection and removal in the boilers of the power stations.
“Clinker removal is planned at least once a month for each power station during planned outages, and forms the bread and butter of our work,” Zinn says.
Further, Skyriders has deployed specific task teams at the new build Medupi and Kusile power stations, in Limpopo and Mpumalanga respectively. These teams are responsible for the safety of other contractors in securing lifelines, safety net installations that catch any falling objects, as well as any required rescues.
Other tasks at these power stations include bolting and bolt torqueing, torque verification and quality control for third parties, and inspection, as well as painting protective steel coatings.
Zinn believes that the Skyriders team has proved its skills and proficiecy in the power generation sector. “The successes at Eskom power stations have resulted in the company being contracted for additional work at some of the facilities, and the future outlook for the company remains positive,” he concludes.