25 July 2013 – Rope access specialist Skyriders and plant care engineering consulting group Carab Tekniva successfully completed the inspection of a 210 m high smoke stack and various boiler pressure components at the Paiton power station in Indonesia.
The two South African-based companies have undertaken inspection and maintenance work at the Paiton power station through a joint partnership since 2004, and recently completed the latest project on the smoke stack and the 700 MW Unit 7 boiler within ten days in May 2013.
Skyriders marketing manager Mike Zinn says, "Although similar services are provided by companies based in Europe, north America and Australia, Skyriders and Carab Tekniva provide the same internationally recognised and accredited offering at a rate that is substantially lower than our international competitors."
A team of six rope access technicians and boiler inspectors from Skyriders worked together with a boiler engineer and engineering technician from Carab Tekniva to undertake inspections on the wall blowers, water wall tube, superheater, reheater tubes and screen tubes, in addition to other mechanical components located inside the boilers and the 210 m smoke stack.
"This was a highly demanding project that had to be completed within ten days. Skyriders was responsible for all physical inspection work, while Carab Tekniva captured and analysed the data, before dictating the required scope of work and advising on a maintenance strategy," he says.
Carab Tekniva boiler engineer Jan Hendrik Fourie, who acted as project manager for the duration of the inspection process, indicates that the company’s boiler health care programme software solution was utilised to monitor the condition of the boiler components, and to proactively monitor the condition of the plant through trend analysis in order to implement maintenance strategies.
Fourie explains that the wear experienced in Indonesian boilers are mostly due to rubbing or fretting of tubes, as a result of retaining lugs or support plates that have broken loose, causing the pressure parts to fret during operation. “Compared to South African boilers where fly ash erosion and sootblower erosion are large contributors to tube failures, the coal used by Paiton has a far lower fly ash content compared to South African coal. This means that less sootblowing is required on the superheater, economiser and reheater elements, which decreases tube material loss rates considerably due to less sootblowing. The calorific value of the Indonesian coal is higher than South African coal, with the result being that coal consumption is less in their boilers to produce the same amount of heat,” Fourie says.
The humid climate and close proximity of the Paiton power station to the ocean proved to be challenging for the inspection team, notes Skyriders rope access team leader Progress Malang. "The close proximity to the ocean results in a large amount of corrosion that has to be dealt with on a regular basis, while the high humidity is physically draining."
Although the language barrier also had an impact on effective communication, Malang points out that this bridge was gapped with the assistance of a translator.